:root {
    --bg-primary: #f0f4f8;
    --text-primary: #1a2b3c;
    --accent-color: #3b82f6;
    --accent-color-dark: #2563eb;
    --card-bg: white;
    --border-radius: 16px;
    --shadow-subtle: 0 8px 20px rgba(0,0,0,0.08);
    --shadow-hover: 0 12px 25px rgba(0,0,0,0.12);
    --body-bg: linear-gradient(90deg, #f6f6f7 0%, #ffffff 100%);
}

[data-theme="dark"] {
    --bg-primary: #1e293b;
    --text-primary: #f1f5f9;
    --accent-color: #60a5fa;
    --accent-color-dark: #3b82f6;
    --card-bg: #334155;
    --shadow-subtle: 0 8px 20px rgba(0,0,0,0.4);
    --shadow-hover: 0 12px 25px rgba(0,0,0,0.5);
    --body-bg: linear-gradient(90deg, #0f172a 0%, #1e293b 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    background: var(--body-bg);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    align-items: center;
    transition: background 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 1000px;
    width: 95%;
    margin: 0 auto;
    padding: 2.5rem;
    background-color: var(--card-bg);
    border-radius: 24px;
    box-shadow: var(--shadow-subtle);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

header {
    text-align: center;
    margin-bottom: 2.5rem;
}

header h1 {
    font-size: 2.75rem;
    color: var(--accent-color);
    margin-bottom: 0.75rem;
    font-weight: 700;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-primary);
    opacity: 0.9;
    font-weight: 300;
}

.header-actions {
    display: flex;
    justify-content: center;
    margin-top: 1rem;
}

.calculator-section {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    margin-bottom: 2.5rem;
    box-shadow: var(--shadow-subtle);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--accent-color);
}

.input-group input,
.input-group select {
    width: 100%;
    padding: 0.875rem 1.25rem;
    border: 2px solid #e0e5eb;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    background-color: var(--card-bg);
    color: var(--text-primary);
}

[data-theme="dark"] .input-group input,
[data-theme="dark"] .input-group select {
    border-color: #4b5563;
}

.input-group input:focus,
.input-group select:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 4px 10px rgba(59,130,246,0.2);
}

.calculator-tabs {
    display: flex;
    margin-bottom: 2rem;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow-subtle);
}

.tab-btn {
    flex: 1;
    padding: 1rem 2rem;
    border: none;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.tab-btn:first-child {
    border-top-left-radius: var(--border-radius);
    border-bottom-left-radius: var(--border-radius);
}

.tab-btn:last-child {
    border-top-right-radius: var(--border-radius);
    border-bottom-right-radius: var(--border-radius);
}

.tab-btn.active {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.tab-btn:not(.active):hover {
    background-color: var(--card-bg);
    transform: translateY(-2px);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.advanced-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
    padding: 2rem;
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    border: 2px solid var(--accent-color);
    border-opacity: 0.2;
}

.advanced-options::before {
    content: '⚙️ Advanced Options';
    position: absolute;
    top: -12px;
    left: 20px;
    background-color: var(--card-bg);
    padding: 0 1rem;
    font-weight: 600;
    color: var(--accent-color);
    font-size: 0.9rem;
}

.advanced-options {
    position: relative;
}

.dimensions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.unit-selector {
    margin-bottom: 2rem;
}

.unit-selector label {
    display: block;
    margin-bottom: 0.75rem;
    font-weight: 600;
    color: var(--accent-color);
}

.radio-group {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.radio-group input[type="radio"] {
    margin-right: 0.5rem;
    width: auto;
}

.radio-group label {
    margin-bottom: 0;
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
}

.calculate-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    box-shadow: 0 6px 15px rgba(59,130,246,0.3);
    width: 100%;
    justify-content: center;
}

.calculate-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(59,130,246,0.4);
}

#ipInput {
    flex-grow: 1;
    padding: 0.875rem 1.25rem;
    border: 2px solid #e0e5eb;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    background-color: var(--card-bg);
    color: var(--text-primary);
}

[data-theme="dark"] #ipInput {
    border-color: #4b5563;
}

#ipInput:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 4px 10px rgba(59,130,246,0.2);
}

#lookupBtn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 6px 15px rgba(59,130,246,0.3);
}

#lookupBtn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(59,130,246,0.4);
}

.my-ip-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.25rem;
    background: linear-gradient(135deg, #10b981, #059669);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 6px 15px rgba(16,185,129,0.3);
}

.my-ip-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(16,185,129,0.4);
}

.result-section {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: var(--shadow-subtle);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.result-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.result-card {
    background-color: var(--bg-primary);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    text-align: left;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.result-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.result-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
}

.result-card h3 {
    color: var(--accent-color);
    margin-bottom: 0.75rem;
    font-weight: 600;
}

.result-card p {
    line-height: 1.6;
    color: var(--text-primary);
    opacity: 0.9;
}

.result-card p strong {
    color: var(--accent-color);
    display: inline-block;
    min-width: 120px;
    font-weight: 600;
    opacity: 1;
}

.map-container {
    width: 100%;
    height: 350px;
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-subtle);
}

.benefits-section {
    background: linear-gradient(135deg, var(--bg-primary) 0%, #e9f0f7 100%);
    padding: 4rem 0;
    text-align: center;
}

.benefits-section .container > p {
    text-align: center;
    margin-bottom: 2.5rem;
    margin-top: 1rem;
    font-size: 1.1rem;
    color: var(--text-primary);
    opacity: 0.9;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.benefits-section h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--accent-color);
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.benefit-card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-subtle);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.benefit-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
}

.benefit-icon {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    transition: transform 0.3s ease;
}

.benefit-card:hover .benefit-icon {
    transform: scale(1.1);
}

.benefit-card h3 {
    margin-bottom: 1rem;
    color: var(--accent-color);
    font-size: 1.25rem;
}

.benefit-card p {
    color: var(--text-primary);
    opacity: 0.9;
    line-height: 1.6;
}

.article-section {
    background: linear-gradient(135deg, #f0f4f8 0%, #e9f0f7 100%);
    padding: 4rem 0;
}

.article-section .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.article-content {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 3rem;
    box-shadow: var(--shadow-subtle);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.article-text h3 {
    color: var(--accent-color);
    margin-top: 2rem;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.article-text p {
    margin-bottom: 1rem;
    line-height: 1.6;
    color: var(--text-primary);
    opacity: 0.9;
}

.article-text ul, 
.article-text ol {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

.article-text ul li, 
.article-text ol li {
    margin-bottom: 0.75rem;
    line-height: 1.6;
    color: var(--text-primary);
    opacity: 0.9;
}

.faq-section {
    margin-top: 2rem;
}

.faq-section h3 {
    text-align: center;
    color: var(--accent-color);
    margin-bottom: 2rem;
    font-size: 2rem;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
    padding: 20px;
}

.faq-item {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-subtle);
    transition: all 0.3s ease;
}

.faq-item:hover {
    transform: translateY(-5px);
}

.faq-item h4 {
    color: var(--accent-color);
    margin-bottom: 0.75rem;
    font-size: 1.25rem;
}

.faq-item p {
    color: var(--text-primary);
    opacity: 0.9;
    line-height: 1.6;
}

.similar-tools-section {
    margin-top: 3rem;
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--shadow-subtle);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.similar-tools-section h3 {
    text-align: center;
    color: var(--accent-color);
    margin-bottom: 2rem;
    font-size: 1.75rem;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.similar-tools-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.similar-tool-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.25rem;
    border-radius: var(--border-radius);
    background-color: var(--bg-primary);
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-subtle);
    justify-content: center;
}

.similar-tool-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
    background-color: white;
}

.tool-icon {
    display: none;
}

.similar-tool-card span {
    transition: color 0.3s ease;
}

.similar-tool-card:hover span {
    color: var(--accent-color);
}

.footer {
    background-color: var(--card-bg);
    padding: 2rem 0;
    box-shadow: 0 -5px 15px rgba(0,0,0,0.05);
    transition: background-color 0.3s ease;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.footer-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-color);
}

.footer-logo a {
    color: var(--accent-color);
    text-decoration: none;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    position: relative;
    transition: all 0.3s ease;
}

.footer-logo a:hover {
    transform: translateY(-3px);
    text-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
}

.footer-logo a:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

.footer-logo a:hover:after {
    width: 80%;
}

.footer-nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.footer-nav a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.footer-nav a:hover {
    color: var(--accent-color);
}

.footer-copyright {
    color: var(--text-primary);
    opacity: 0.8;
    font-size: 0.9rem;
}

.footer-copyright a {
    color: var(--accent-color);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.footer-copyright a:hover {
    color: var(--accent-color-dark);
    text-decoration: underline;
}

.article-title {
    text-align: center;
    color: var(--accent-color);
    font-size: 2.5rem;
    margin-bottom: 2rem;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

h1.main-section-title {
    font-size: 3rem;
    text-align: center;
    background: linear-gradient(45deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    color: transparent;
    font-weight: 800;
    position: relative;
    margin-bottom: 0.5rem;
    line-height: 1.2;
    letter-spacing: -0.05em;
    text-shadow: 0 4px 15px rgba(59,130,246,0.2);
    padding: 0 1rem;
    transition: all 0.3s ease;
}

h1.main-section-title::before {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 2px;
}

h1.main-section-title:hover {
    transform: scale(1.02);
    text-shadow: 0 6px 20px rgba(59,130,246,0.3);
}

.view-all-tools {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 1.5rem;
    gap: 1rem;
}

.view-all-tools #newCalcBtn {
    background: white;
    color: var(--accent-color);
    border: 2px solid rgba(59,130,246,0.25);
    box-shadow: 0 6px 16px rgba(59,130,246,0.12);
    padding: 0.75rem 1.25rem;
    border-radius: 999px;
    font-weight: 700;
}

.view-all-tools #newCalcBtn:hover {
    background: linear-gradient(135deg, rgba(59,130,246,0.06), rgba(37,99,235,0.04));
    transform: translateY(-2px);
    box-shadow: 0 10px 22px rgba(59,130,246,0.18);
}

.tools-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    background: linear-gradient(135deg, #8b5cf6, #6d28d9);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 6px 15px rgba(109, 40, 217, 0.3);
    text-decoration: none;
}

.tools-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(109, 40, 217, 0.4);
}

.toast-notification {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: linear-gradient(135deg, #f44336, #e53935);
    color: white;
    padding: 16px 32px;
    border-radius: var(--border-radius);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
    display: flex;
    align-items: center;
    gap: 12px;
    z-index: 1000;
    opacity: 0;
    transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    font-weight: 500;
    min-width: 300px;
    max-width: 500px;
    text-align: center;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.toast-notification.show {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
}

.toast-notification svg {
    flex-shrink: 0;
}

.dark-mode-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
    position: relative;
    overflow: hidden;
}

.dark-mode-toggle::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #764ba2 0%, #667eea 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.dark-mode-toggle:hover::before {
    opacity: 1;
}

.dark-mode-toggle:hover {
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

.dark-mode-toggle svg {
    stroke: white;
    transition: all 0.3s ease;
    position: relative;
    z-index: 1;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.2));
}

[data-theme="dark"] .sun-icon {
    display: none;
}

[data-theme="light"] .moon-icon,
:root .moon-icon {
    display: none;
}

[data-theme="dark"] .moon-icon {
    display: block;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.card-header h3 {
    margin-bottom: 0;
}

.copy-btn {
    background: none;
    border: none;
    color: var(--accent-color);
    cursor: pointer;
    padding: 0.25rem;
    border-radius: 6px;
    transition: all 0.3s ease;
    opacity: 0.7;
}

.copy-btn:hover {
    opacity: 1;
    background-color: var(--accent-color);
    color: white;
    transform: scale(1.1);
}

.export-section {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    justify-content: center;
}

.export-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: linear-gradient(135deg, #6366f1, #4f46e5);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
    font-size: 0.9rem;
}

.export-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(99, 102, 241, 0.4);
}

#copyAllBtn {
    background: linear-gradient(135deg, #10b981, #059669);
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

#copyAllBtn:hover {
    box-shadow: 0 6px 16px rgba(16, 185, 129, 0.4);
}

#newCalcBtn {
    background: linear-gradient(135deg, #6b7280, #4b5563);
    box-shadow: 0 4px 12px rgba(107,114,128,0.3);
}

#newCalcBtn:hover {
    box-shadow: 0 6px 16px rgba(107,114,128,0.4);
}

.field-toggles {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 2rem;
    border: 2px solid var(--accent-color);
    border-opacity: 0.2;
}

.field-toggles h4 {
    color: var(--accent-color);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.toggle-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
}

.toggle-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem;
    background-color: var(--card-bg);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.toggle-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.15);
}

.toggle-item input[type="checkbox"] {
    width: auto;
    margin: 0;
    accent-color: var(--accent-color);
}

.toggle-item input[type="checkbox"]:checked + .toggle-label {
    color: var(--accent-color);
    font-weight: 600;
}

.toggle-item:has(input:checked) {
    border-color: var(--accent-color);
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(37, 99, 235, 0.05));
}

.toggle-label {
    font-weight: 500;
    color: var(--text-primary);
    transition: all 0.3s ease;
}

.calculation-history {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    margin-bottom: 2.5rem;
    box-shadow: var(--shadow-subtle);
    transition: all 0.3s ease;
}

.calculation-history h3 {
    color: var(--accent-color);
    margin-bottom: 2rem;
    font-size: 1.75rem;
    font-weight: 700;
    text-align: center;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    position: relative;
    padding-bottom: 1rem;
}

.calculation-history h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 2px;
}

.history-controls {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    justify-content: center;
    flex-wrap: wrap;
}

.clear-btn, .compare-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    font-size: 0.95rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.clear-btn {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
}

.clear-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(239, 68, 68, 0.4);
}

.compare-btn {
    background: linear-gradient(135deg, #8b5cf6, #7c3aed);
    color: white;
}

.compare-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.4);
}

.compare-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    background: linear-gradient(135deg, #9ca3af, #6b7280);
    transform: none;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.history-list {
    max-height: 500px;
    overflow-y: auto;
    border: 2px solid var(--accent-color);
    border-opacity: 0.1;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    background: var(--bg-primary);
    scrollbar-width: thin;
    scrollbar-color: var(--accent-color) var(--bg-primary);
}

.history-list::-webkit-scrollbar {
    width: 6px;
}

.history-list::-webkit-scrollbar-track {
    background: var(--bg-primary);
    border-radius: 3px;
}

.history-list::-webkit-scrollbar-thumb {
    background: var(--accent-color);
    border-radius: 3px;
}

.history-list::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color-dark);
}

.history-item {
    display: flex;
    align-items: center;
    padding: 1.5rem;
    margin-bottom: 1rem;
    background-color: var(--card-bg);
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    position: relative;
    overflow: hidden;
    width: 100%;
}

.history-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    transition: width 0.3s ease;
}

.history-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
    border-color: var(--accent-color);
    border-opacity: 0.3;
}

.history-item:hover::before {
    width: 6px;
}

.history-checkbox {
    display: flex;
    align-items: center;
    margin-right: 1.5rem;
    padding: 0.5rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.history-checkbox:hover {
    background-color: var(--bg-primary);
}

.compare-checkbox {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--accent-color);
    border-radius: 4px;
}

.history-info {
    flex: 1;
    min-width: 0;
}

.history-project {
    font-weight: 700;
    color: var(--accent-color);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.history-project::before {
    content: '🏗️';
    font-size: 1rem;
}

.history-details {
    color: var(--text-primary);
    opacity: 0.8;
    font-size: 0.9rem;
    line-height: 1.4;
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    align-items: center;
}

.history-detail-item {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.25rem 0.75rem;
    background: var(--bg-primary);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

.history-detail-icon {
    width: 14px;
    height: 14px;
    opacity: 0.7;
}

.history-actions {
    display: flex;
    gap: 0.5rem;
    margin-left: 1rem;
    flex-shrink: 0;
}

.history-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.85rem;
    font-weight: 500;
    color: white;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.load-btn {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
}

.load-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.delete-btn {
    background: linear-gradient(135deg, #ef4444, #dc2626);
}

.delete-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.3);
}

.history-list:empty::before {
    content: '📋 No calculations yet. Start by calculating your first project!';
    display: block;
    text-align: center;
    color: var(--text-primary);
    opacity: 0.6;
    font-style: italic;
    padding: 3rem;
    font-size: 1.1rem;
}

.comparison-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.comparison-content {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2rem;
    max-width: 90vw;
    max-height: 90vh;
    overflow: auto;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.comparison-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--accent-color);
}

.comparison-header h3 {
    color: var(--accent-color);
    font-size: 1.5rem;
    margin: 0;
}

.close-comparison {
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: color 0.3s ease;
    line-height: 1;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-comparison:hover {
    color: var(--accent-color);
}

.comparison-table-container {
    overflow-x: auto;
    margin-bottom: 1.5rem;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px;
}

.comparison-table th,
.comparison-table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--accent-color);
    border-right: 1px solid var(--accent-color);
    color: var(--text-primary);
}

.comparison-table th {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    font-weight: 600;
    position: sticky;
    top: 0;
}

.comparison-table th:first-child {
    background: var(--bg-primary);
    color: var(--accent-color);
    font-weight: 700;
}

.comparison-table td:first-child {
    background: var(--bg-primary);
    font-weight: 600;
    color: var(--accent-color);
}

.comparison-table tbody tr:hover {
    background-color: var(--bg-primary);
}

.comparison-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
}

.export-comparison-btn,
.close-comparison-btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
}

.export-comparison-btn {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.export-comparison-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(59, 130, 246, 0.4);
}

.close-comparison-btn {
    background: linear-gradient(135deg, #6b7280, #4b5563);
    color: white;
    box-shadow: 0 4px 12px rgba(107, 114, 128, 0.3);
}

.close-comparison-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(107, 114, 128, 0.4);
}

.result-tabs {
    display: flex;
    margin-bottom: 2rem;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow-subtle);
}

.result-tab-btn {
    flex: 1;
    padding: 1rem 1.5rem;
    border: none;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.result-tab-btn.active {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.result-tab-btn:not(.active):hover {
    background-color: var(--card-bg);
    transform: translateY(-2px);
}

.result-tab-content {
    display: none;
}

.result-tab-content.active {
    display: block;
}

.materials-breakdown {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.materials-breakdown canvas {
    max-width: 400px;
    max-height: 300px;
    width: 100%;
    height: auto;
    flex-shrink: 0;
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.materials-details {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    width: 100%;
    max-width: 600px;
    flex-grow: 1;
}

.material-item {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.08), rgba(37, 99, 235, 0.04));
    border-radius: 16px;
    text-align: center;
    border: 1px solid rgba(59, 130, 246, 0.15);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.material-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 3px 3px 0 0;
}

.material-item:hover {
    border-color: var(--accent-color);
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(59, 130, 246, 0.15);
}

.material-name {
    font-weight: 700;
    color: var(--accent-color);
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.material-amount {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
}

.material-cost {
    font-weight: 700;
    color: var(--accent-color);
    font-size: 1rem;
    padding: 0.5rem 1rem;
    background: rgba(59, 130, 246, 0.1);
    border-radius: 25px;
    border: 1px solid rgba(59, 130, 246, 0.2);
}

.cost-breakdown {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.cost-breakdown canvas {
    max-width: 400px;
    max-height: 300px;
    width: 100%;
    height: auto;
    flex-shrink: 0;
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.cost-comparison {
    width: 100%;
    max-width: 600px;
}

.cost-comparison h4 {
    color: var(--accent-color);
    margin-bottom: 1.5rem;
    font-size: 1.3rem;
    text-align: center;
    font-weight: 700;
}

.region-costs {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
    width: 100%;
    max-width: none;
}

.region-item {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.08), rgba(5, 150, 105, 0.04));
    border-radius: 16px;
    text-align: center;
    border: 1px solid rgba(16, 185, 129, 0.15);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.region-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #10b981, #059669);
    border-radius: 3px 3px 0 0;
}

.region-item:hover {
    border-color: #10b981;
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(16, 185, 129, 0.15);
}

.region-name {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.region-cost {
    font-weight: 700;
    color: #10b981;
    font-size: 1.2rem;
    padding: 0.5rem 1rem;
    background: rgba(16, 185, 129, 0.1);
    border-radius: 25px;
    border: 1px solid rgba(16, 185, 129, 0.2);
}

.visualization-container {
    text-align: center;
    overflow: hidden;
    padding: 1rem;
}

.visualization-main {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    align-items: center;
    margin-bottom: 2rem;
}

.visualization-canvas-container {
    flex-shrink: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.visualization-container canvas {
    max-width: 500px;
    height: auto;
    max-height: 400px;
    border-radius: 12px;
}

.dimensions-display {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-top: 0;
    width: 100%;
    max-width: 600px;
    min-width: 200px;
}

.dimension-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.08), rgba(124, 58, 237, 0.04));
    border-radius: 16px;
    border: 1px solid rgba(139, 92, 246, 0.15);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.dimension-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #8b5cf6, #7c3aed);
    border-radius: 3px 3px 0 0;
}

.dimension-item:hover {
    border-color: #8b5cf6;
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(139, 92, 246, 0.15);
}

.dim-label {
    font-weight: 600;
    color: var(--accent-color);
    font-size: 0.7rem;
    background: white;
    padding: 2px 6px;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.label-length {
    bottom: -25px;
    left: 50%;
    transform: translateX(-50%);
}

.label-width {
    right: -35px;
    top: 50%;
    transform: translateY(-50%) rotate(90deg);
    transform-origin: center;
}

.label-thickness {
    top: -25px;
    right: -15px;
    font-size: 0.6rem;
}

/* Saved Projects Bar */
.saved-projects-section {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 1.25rem 1.25rem 0.75rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-subtle);
}

.saved-projects-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.saved-projects-header h3 {
    color: var(--accent-color);
    font-size: 1.25rem;
    margin: 0;
}

.saved-projects-actions {
    display: flex;
    gap: 0.5rem;
}

.saved-action-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.5rem 0.75rem;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(59,130,246,0.3);
    font-size: 0.85rem;
}

.saved-action-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(59,130,246,0.4);
}

.saved-projects-bar {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1rem;
    align-items: stretch;
    padding-bottom: 0.75rem;
}

.saved-project-card {
    display: flex;
    flex-direction: column;
    padding: 14px;
    background: var(--card-bg);
    position: relative;
    overflow: hidden;
}

.saved-project-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 28px rgba(59,130,246,0.18);
    border-color: rgba(59,130,246,0.35);
}

.saved-project-card::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 16px;
    pointer-events: none;
    background: radial-gradient(120px 80px at 20% 10%, rgba(59,130,246,0.12), transparent 60%);
}

.saved-project-card .saved-project-title {
    display: block;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.saved-chip-meta {
    margin-bottom: 8px;
    padding: 6px 10px;
    background: linear-gradient(135deg, rgba(59,130,246,0.06), rgba(37,99,235,0.04));
    border: 1px solid rgba(59,130,246,0.12);
    border-radius: 10px;
}

.saved-chip-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.5rem;
    margin-top: auto;
}

.saved-chip-btn {
    background: transparent;
    color: var(--accent-color);
    border: 1px solid rgba(59,130,246,0.35);
    padding: 0.4rem 0.7rem;
    cursor: pointer;
}

.saved-chip-btn.delete {
    color: #ef4444;
    border-color: rgba(239,68,68,0.25);
}

.saved-chip-btn.delete:hover {
    background: #ef4444;
    color: white;
}

.saved-card-head {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 8px;
    margin-bottom: 6px;
}

.saved-icon {
    width: 28px;
    height: 28px;
    border-radius: 8px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: #fff;
    margin-right: 8px;
    box-shadow: 0 4px 10px rgba(59,130,246,0.25);
}

.saved-icon svg {
    width: 18px;
    height: 18px;
    display: block;
    stroke: currentColor;
}

/* Empty state */
.saved-projects-bar:empty::before {
    content: 'No saved projects yet. Use "Save Project" to add one.';
    color: var(--text-primary);
    opacity: 0.6;
    font-style: italic;
    padding: 0.5rem 0.25rem 1rem;
}

.view-controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1rem;
}

.view-btn {
    padding: 1rem 2rem;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
    font-size: 0.95rem;
}

.view-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

.tips-section {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2.5rem;
    box-shadow: var(--shadow-subtle);
    transition: all 0.3s ease;
}

.tips-section h3 {
    color: var(--accent-color);
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

.tips-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
}

.tip-item {
    padding: 1.5rem;
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--accent-color);
    transition: all 0.3s ease;
}

.tip-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-hover);
}

.tip-item.pro {
    border-left-color: #10b981;
    background: linear-gradient(135deg, rgba(16,185,129,0.08), rgba(5,150,105,0.04));
}

.tip-badge {
    display: inline-block;
    padding: 4px 8px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 700;
    color: #065f46;
    background: #d1fae5;
    margin-bottom: 8px;
}

.tip-list {
    margin: 8px 0 0 1rem;
}

.tip-list li {
    margin: 4px 0;
}

.tip-meta {
    font-size: 12px;
    color: rgba(0,0,0,0.5);
    margin-top: 8px;
}

.input-group.disabled {
    opacity: 0.5;
    pointer-events: none;
}

.input-group.disabled input,
.input-group.disabled select {
    background-color: var(--bg-primary);
    cursor: not-allowed;
}

.project-visual {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2rem;
    border: 2px solid var(--accent-color);
    border-opacity: 0.2;
}

.visual-container {
    display: flex;
    gap: 2rem;
    align-items: center;
    justify-content: center;
}

.visual-diagram {
    flex: 1;
    max-width: 300px;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--card-bg);
    border-radius: 12px;
    border: 1px solid var(--accent-color);
    border-opacity: 0.3;
    position: relative;
    overflow: hidden;
}

.visual-description {
    flex: 1;
    max-width: 250px;
    color: var(--text-primary);
    font-size: 0.9rem;
    line-height: 1.6;
}

.visual-description h4 {
    color: var(--accent-color);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.visual-description ul {
    margin: 0.5rem 0 0 1rem;
    padding: 0;
}

.visual-description li {
    margin-bottom: 0.25rem;
    color: var(--text-primary);
    opacity: 0.8;
}

.diagram-shape {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.shape-3d {
    position: relative;
    transform-style: preserve-3d;
    animation: rotate3d 4s ease-in-out infinite;
}

@keyframes rotate3d {
    0%, 100% { transform: rotateY(0deg) rotateX(0deg); }
    25% { transform: rotateY(90deg) rotateX(0deg); }
    50% { transform: rotateY(90deg) rotateX(15deg); }
    75% { transform: rotateY(0deg) rotateX(15deg); }
}

.slab-shape {
    width: 120px;
    height: 80px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 4px;
    position: relative;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
}

.slab-shape::after {
    content: '';
    position: absolute;
    top: -8px;
    left: 8px;
    width: 120px;
    height: 80px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.8), rgba(37, 99, 235, 0.8));
    border-radius: 4px;
    z-index: -1;
}

.column-shape {
    width: 60px;
    height: 140px;
    background: linear-gradient(180deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 30px;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
    position: relative;
}

.column-shape::before {
    content: '';
    position: absolute;
    top: -5px;
    left: -5px;
    width: 70px;
    height: 20px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.6), rgba(37, 99, 235, 0.6));
    border-radius: 35px;
}

.column-shape::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: -5px;
    width: 70px;
    height: 20px;
    background: linear-gradient(135deg, var(--accent-color-dark), var(--accent-color));
    border-radius: 35px;
}

.beam-shape {
    width: 140px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 6px;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
    position: relative;
}

.beam-shape::after {
    content: '';
    position: absolute;
    top: -6px;
    left: 6px;
    width: 140px;
    height: 40px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.7), rgba(37, 99, 235, 0.7));
    border-radius: 6px;
    z-index: -1;
}

.stairs-shape {
    position: relative;
    width: 120px;
    height: 100px;
}

.step {
    position: absolute;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 2px;
    box-shadow: 0 2px 4px rgba(59, 130, 246, 0.3);
}

.step:nth-child(1) {
    width: 30px;
    height: 20px;
    bottom: 0;
    left: 0;
}

.step:nth-child(2) {
    width: 60px;
    height: 20px;
    bottom: 20px;
    left: 0;
}

.step:nth-child(3) {
    width: 90px;
    height: 20px;
    bottom: 40px;
    left: 0;
}

.step:nth-child(4) {
    width: 120px;
    height: 20px;
    bottom: 60px;
    left: 0;
}

.wall-shape {
    width: 20px;
    height: 120px;
    background: linear-gradient(180deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 4px;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
    position: relative;
}

.wall-shape::after {
    content: '';
    position: absolute;
    top: 0;
    left: -8px;
    width: 20px;
    height: 120px;
    background: linear-gradient(180deg, rgba(59, 130, 246, 0.6), rgba(37, 99, 235, 0.6));
    border-radius: 4px;
    z-index: -1;
}

.pool-shape {
    width: 140px;
    height: 80px;
    background: linear-gradient(135deg, #06b6d4, #0891b2);
    border-radius: 20px;
    position: relative;
    box-shadow: 0 4px 8px rgba(6, 182, 212, 0.3);
}

.pool-shape::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 8px;
    right: 8px;
    bottom: 8px;
    background: linear-gradient(135deg, rgba(6, 182, 212, 0.6), rgba(8, 145, 178, 0.6));
    border-radius: 14px;
}

.foundation-shape {
    position: relative;
    width: 120px;
    height: 80px;
}

.foundation-base {
    width: 120px;
    height: 30px;
    background: linear-gradient(135deg, var(--accent-color-dark), var(--accent-color));
    border-radius: 4px;
    position: absolute;
    bottom: 0;
}

.foundation-wall {
    width: 80px;
    height: 50px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 4px 4px 0 0;
    position: absolute;
    top: 0;
    left: 20px;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
}

.curb-shape {
    position: relative;
    width: 140px;
    height: 40px;
}

.curb-main {
    width: 140px;
    height: 20px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 4px;
    position: absolute;
    top: 0;
}

.curb-gutter {
    width: 140px;
    height: 15px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.7), rgba(37, 99, 235, 0.7));
    border-radius: 0 0 8px 8px;
    position: absolute;
    bottom: 0;
    right: 0;
}

.curb-gutter-shape {
    width: 150px;
    height: 70px;
    position: relative;
}

.curb-gutter-shape .curb-section {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 26px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 6px 6px 0 0;
}

.curb-gutter-shape .gutter-section {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 34px;
    background: linear-gradient(135deg, rgba(59,130,246,0.75), rgba(37,99,235,0.75));
    border-radius: 0 0 10px 10px;
}

.culvert-shape {
    width: 60px;
    height: 60px;
    border: 12px solid var(--accent-color);
    border-radius: 50%;
    background: transparent;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
    position: relative;
}

.culvert-shape::after {
    content: '';
    position: absolute;
    top: -18px;
    left: -18px;
    width: 96px;
    height: 20px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.4), rgba(37, 99, 235, 0.4));
    border-radius: 48px;
}

.bridge-shape {
    position: relative;
    width: 160px;
    height: 60px;
}

.bridge-deck {
    width: 160px;
    height: 20px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 4px;
    position: absolute;
    top: 20px;
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.3);
}

.bridge-support {
    width: 8px;
    height: 40px;
    background: linear-gradient(180deg, var(--accent-color-dark), var(--accent-color));
    position: absolute;
    bottom: 0;
}

.bridge-support:nth-child(2) { left: 30px; }
.bridge-support:nth-child(3) { left: 76px; }
.bridge-support:nth-child(4) { left: 122px; }

.square-footing-shape {
    width: 120px; height: 120px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 8px; box-shadow: 0 4px 8px rgba(59,130,246,.3);
}

.hole-shape {
    width: 140px; height: 100px; position: relative;
    background: linear-gradient(135deg, #e5e7eb, #cbd5e1);
    border-radius: 10px; border: 2px dashed rgba(59,130,246,.4);
}

.hole-shape .hole-interior {
    position: absolute; inset: 12px;
    background: linear-gradient(135deg, #94a3b8, #64748b);
    border-radius: 8px; box-shadow: inset 0 6px 14px rgba(0,0,0,.25);
}

.round-footing-shape, .circular-slab-shape {
    width: 120px; height: 120px; border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    box-shadow: 0 4px 10px rgba(59,130,246,.3); position: relative;
}

.tube-shape {
    width: 130px; height: 130px; position: relative; border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    box-shadow: 0 4px 10px rgba(59,130,246,.3);
}

.tube-shape .tube-interior {
    position: absolute; inset: 20px; border-radius: 50%;
    background: var(--card-bg); box-shadow: inset 0 6px 14px rgba(0,0,0,.25);
}

.square-footing-shape, .hole-shape, .round-footing-shape, .circular-slab-shape,
.tube-shape, .curb-gutter-shape, .barrier-shape {
    display: block; margin: 0 auto;
}

.barrier-shape {
    width: 150px; height: 70px; position: relative;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    border-radius: 10px; box-shadow: 0 4px 10px rgba(59,130,246,.3);
}

.essential-field-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    transform: scale(0.8);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    padding: 1rem;
}

.essential-field-modal.show {
    opacity: 1;
    transform: scale(1);
}

.essential-field-modal.closing {
    opacity: 0;
    transform: scale(0.9);
    transition: all 0.3s ease-out;
}

.essential-field-content {
    background: var(--card-bg);
    border-radius: 20px;
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    position: relative;
    animation: modalSlideUp 0.4s ease-out;
}

@keyframes modalSlideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.essential-field-header {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
    padding: 2rem;
    border-radius: 20px 20px 0 0;
    display: flex;
    align-items: center;
    gap: 1rem;
    position: relative;
}

.warning-icon {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    padding: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: pulseWarning 2s infinite;
}

@keyframes pulseWarning {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.essential-field-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0;
    flex: 1;
}

.close-essential-modal {
    background: none;
    border: none;
    color: white;
    font-size: 2rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: all 0.3s ease;
    line-height: 1;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-essential-modal:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: rotate(90deg);
}

.essential-field-body {
    padding: 2rem;
    color: var(--text-primary);
}

.essential-field-body p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.6;
}

.warning-details {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.1), rgba(220, 38, 38, 0.05));
    border-left: 4px solid #ef4444;
    padding: 1.5rem;
    border-radius: 12px;
    margin-bottom: 1.5rem;
}

.warning-details h4 {
    color: #ef4444;
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.warning-details ul {
    list-style: none;
    padding-left: 0;
    margin: 0;
}

.warning-details li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-primary);
    opacity: 0.9;
}

.warning-details li:before {
    content: '•';
    color: #ef4444;
    font-size: 1.2rem;
    position: absolute;
    left: 0;
}

.recommendation {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(37, 99, 235, 0.05));
    border-left: 4px solid var(--accent-color);
    padding: 1.5rem;
    border-radius: 12px;
    margin-bottom: 1.5rem;
}

.recommendation h4 {
    color: var(--accent-color);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.recommendation p {
    margin: 0;
    color: var(--text-primary);
    opacity: 0.9;
    line-height: 1.6;
}

.essential-field-actions {
    padding: 1.5rem 2rem 2rem;
    display: flex;
    gap: 1rem;
    flex-direction: column;
}

.re-enable-field {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-color-dark));
    color: white;
    border: none;
    padding: 1rem 1.5rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.re-enable-field:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

.continue-anyway {
    background: linear-gradient(135deg, #6b7280, #4b5563);
    color: white;
    border: none;
    padding: 1rem 1.5rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.continue-anyway:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(107, 114, 128, 0.4);
}

.clear-history-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    transform: scale(0.8);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    padding: 1rem;
}

.clear-history-modal.show {
    opacity: 1;
    transform: scale(1);
}

.clear-history-modal.closing {
    opacity: 0;
    transform: scale(0.9);
    transition: all 0.3s ease-out;
}

.clear-history-content {
    background: var(--card-bg);
    border-radius: 20px;
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    position: relative;
    animation: modalSlideUp 0.4s ease-out;
}

.clear-history-header {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
    padding: 2rem;
    border-radius: 20px 20px 0 0;
    display: flex;
    align-items: center;
    gap: 1rem;
    position: relative;
}

.clear-history-header .warning-icon {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    padding: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: pulseWarning 2s infinite;
}

.clear-history-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0;
    flex: 1;
}

.close-clear-modal {
    background: none;
    border: none;
    color: white;
    font-size: 2rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: all 0.3s ease;
    line-height: 1;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-clear-modal:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: rotate(90deg);
}

.clear-history-body {
    padding: 2rem;
    color: var(--text-primary);
}

.clear-history-body p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.6;
}

.history-count {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(37, 99, 235, 0.05));
    border-left: 4px solid var(--accent-color);
    padding: 1rem;
    border-radius: 12px;
    margin-bottom: 1.5rem;
}

.history-count p {
    margin: 0;
    color: var(--accent-color);
    font-weight: 600;
}

.clear-history-actions {
    padding: 1.5rem 2rem 2rem;
    display: flex;
    gap: 1rem;
    flex-direction: column;
}

.confirm-clear {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
    border: none;
    padding: 1rem 1.5rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.confirm-clear:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(239, 68, 68, 0.4);
}

.cancel-clear {
    background: linear-gradient(135deg, #6b7280, #4b5563);
    color: white;
    border: none;
    padding: 1rem 1.5rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.cancel-clear:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(107, 114, 128, 0.4);
}

@media (max-width: 1024px) {
    .container {
        width: 90%;
        padding: 1.5rem;
    }

    .lookup-section {
        flex-direction: column;
    }

    #ipInput, 
    #lookupBtn {
        width: 100%;
    }

    .benefits-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .benefits-section h2 {
        font-size: 2rem;
    }

    .view-all-tools {
        flex-direction: column;
        gap: 1rem;
    }

    .article-content {
        flex-direction: column;
        text-align: center;
    }

    .materials-breakdown,
    .cost-breakdown {
        gap: 1.5rem;
    }

    .materials-breakdown canvas,
    .cost-breakdown canvas {
        max-width: 350px;
        max-height: 250px;
    }

    .materials-details,
    .region-costs {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        max-width: 500px;
    }

    .visualization-main {
        gap: 1.5rem;
    }

    .dimensions-display {
        grid-template-columns: repeat(2, 1fr);
        max-width: 500px;
    }
}

@media (max-width: 768px) {
    body {
        align-items: flex-start;
        padding: 1rem 0;
    }

    .container {
        border-radius: 0;
        width: 100%;
        padding: 1rem;
    }

    .lookup-section {
        flex-direction: column;
        align-items: stretch;
    }

    header h1 {
        font-size: 2rem;
    }

    .result-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }

    .result-section {
        padding: 1.5rem;
    }

    .result-card {
        padding: 1rem;
    }

    .benefits-grid {
        grid-template-columns: 1fr;
    }

    .benefits-section {
        padding: 2rem 1rem;
    }

    .article-section h2 {
        font-size: 2rem;
    }

    .article-content {
        padding: 2rem;
    }

    .faq-grid {
        grid-template-columns: 1fr;
    }

    .footer-nav ul {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }

    .faq-item {
        padding: 1.25rem;
    }

    .article-title {
        font-size: 2rem;
    }

    .similar-tools-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .export-section {
        flex-direction: column;
        align-items: stretch;
    }
    
    .export-btn {
        justify-content: center;
        width: 100%;
    }
    
    .dimensions-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .radio-group {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .tab-btn {
        padding: 0.75rem 1rem;
        font-size: 0.9rem;
    }
    
    .advanced-options {
        grid-template-columns: 1fr;
        padding: 1.5rem;
    }
    
    .toggle-group {
        grid-template-columns: repeat(2, 1fr);
        gap: 0.75rem;
    }
    
    .materials-breakdown,
    .cost-breakdown {
        gap: 0.75rem;
    }
    
    .materials-breakdown canvas,
    .cost-breakdown canvas,
    .visualization-container canvas {
        max-width: 100%;
        width: 100%;
        height: 200px;
    }
    
    .materials-details,
    .region-costs,
    .dimensions-display {
        grid-template-columns: 1fr;
        max-width: 100%;
    }
    
    .material-item,
    .region-item,
    .dimension-item {
        padding: 1.25rem;
    }
    
    .view-controls {
        flex-direction: column;
        align-items: center;
        gap: 0.75rem;
    }
    
    .view-btn {
        width: 100%;
        max-width: 250px;
        padding: 0.875rem 1.5rem;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .result-grid {
        grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 1.75rem;
    }

    .lookup-section {
        gap: 0.5rem;
    }

    #ipInput, 
    #lookupBtn {
        font-size: 0.9rem;
        padding: 0.625rem 1rem;
    }

    .similar-tools-grid {
        grid-template-columns: 1fr;
    }
    
    .toggle-group {
        grid-template-columns: 1fr;
    }
    
    .result-tab-btn {
        flex: 1 1 100%;
    }
    
    .materials-breakdown canvas,
    .cost-breakdown canvas,
    .visualization-container canvas {
        height: 150px;
    }
    
    .visualization-container {
        padding: 0.5rem;
    }
    
    .view-controls {
        gap: 0.5rem;
    }
    
    .view-btn {
        padding: 0.75rem 1.25rem;
        font-size: 0.85rem;
    }
}