:root {
    --bg-primary: #0b0f13;
    --bg-secondary: #14191f;
    --bg-card: rgba(255, 255, 255, 0.03);
    --text-primary: #ffffff;
    --text-secondary: #a0aec0;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --accent-gradient: linear-gradient(135deg, #3b82f6, #1d4ed8);
    --border: rgba(255, 255, 255, 0.1);
    --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -2px rgba(0, 0, 0, 0.2);
    --glass: rgba(255, 255, 255, 0.05);
    --radius: 1rem;
    --radius-2xl: 1.5rem;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --backdrop: blur(20px) saturate(180%);
}

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

/* Optimized smooth scrolling */
html {
    scroll-behavior: smooth;
    font-size: 100%;
    text-rendering: optimizeSpeed;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    padding: 0;
    margin: 0;
    overflow-x: hidden;
    /* Performance optimizations */
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Container with responsive padding */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Enhanced Header with glass morphism */
header {
    background: rgba(20, 25, 31, 0.8);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: var(--backdrop);
    -webkit-backdrop-filter: var(--backdrop);
    transition: var(--transition);
}

/* Header scroll effect */
header.scrolled {
    padding: 0.75rem 0;
    background: rgba(11, 15, 19, 0.95);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
    transition: var(--transition);
}

.logo img {
    border-radius: 12px;
    transition: var(--transition);
}

.logo:hover {
    transform: translateY(-1px);
}

/* Mobile menu button (hidden on desktop) */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    margin: 2px 0;
    transition: var(--transition);
    transform-origin: center;
}

/* Navigation styles */
nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 0;
    position: relative;
}

nav a:hover, nav a.active {
    color: var(--text-primary);
}

nav a.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--accent-gradient);
    border-radius: 2px;
    animation: underlineGrow 0.3s ease;
}

@keyframes underlineGrow {
    from { width: 0; }
    to { width: 100%; }
}

/* Hero Section with subtle animation */
.hero {
    text-align: center;
    padding: 3rem 1rem;
    max-width: 800px;
    margin: 0 auto;
    animation: fadeInUp 0.8s ease;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    line-height: 1.2;
    background: linear-gradient(135deg, #fff 0%, #a0aec0 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.125rem;
    color: var(--text-secondary);
}

/* Tabs Container */
.tabs-container {
    margin: 2rem 0;
}

.tab-content {
    display: none;
    animation: fadeIn 0.5s ease;
}

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Enhanced Converter Card with glass effect */
.converter-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border);
    border-radius: var(--radius-2xl);
    padding: 2rem;
    box-shadow: var(--shadow);
    backdrop-filter: var(--backdrop);
    -webkit-backdrop-filter: var(--backdrop);
    margin-bottom: 2rem;
    transition: var(--transition);
}

.converter-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 10px 10px -5px rgba(0, 0, 0, 0.2);
}

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

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.input-group input {
    width: 100%;
    padding: 0.875rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.input-group input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

/* Voice input button with animation */
.voice-btn {
    position: absolute;
    right: 0.75rem;
    top: 2.5rem;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: var(--transition);
    z-index: 2;
}

.voice-btn:hover, .voice-btn.listening {
    background: var(--accent);
    color: white;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(59, 130, 246, 0.4); }
    70% { box-shadow: 0 0 0 10px rgba(59, 130, 246, 0); }
    100% { box-shadow: 0 0 0 0 rgba(59, 130, 246, 0); }
}

/* Unit selectors with flexbox gap fallback for older browsers */
.unit-selectors {
    display: flex;
    align-items: flex-end;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.select-group {
    flex: 1;
}

.select-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.select-group select {
    width: 100%;
    padding: 0.875rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-primary);
    font-size: 1rem;
    appearance: none;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 1em;
    transition: var(--transition);
}

.select-group select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.reverse-btn {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 0.875rem 1rem;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.reverse-btn:hover {
    background: var(--accent);
    transform: rotate(180deg);
}

.precision-controls {
    margin-bottom: 1.5rem;
}

.precision-controls label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.precision-options {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.precision-btn {
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.875rem;
}

.precision-btn.active, .precision-btn:hover {
    background: var(--accent);
    border-color: var(--accent);
    transform: translateY(-2px);
}

/* Convert button with gradient and hover effect */
.convert-btn {
    width: 100%;
    padding: 1rem;
    background: var(--accent-gradient);
    border: none;
    border-radius: var(--radius);
    color: white;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 1.5rem;
    position: relative;
    overflow: hidden;
}

.convert-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: 0.5s;
}

.convert-btn:hover::before {
    left: 100%;
}

.convert-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(59, 130, 246, 0.3);
}

/* Result container with animation */
.result-container {
    background: var(--bg-secondary);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 2rem;
    animation: scaleIn 0.3s ease;
}

@keyframes scaleIn {
    from { transform: scale(0.95); opacity: 0; }
    to { transform: scale(1); opacity: 1; }
}

.result-container h3 {
    margin-bottom: 1rem;
    font-size: 1.25rem;
    color: var(--text-secondary);
}

.result {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--accent);
    transition: var(--transition);
}

.formula-info {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    position: relative;
    cursor: help;
    padding: 0.5rem;
    border-radius: var(--radius);
    background: rgba(0, 0, 0, 0.2);
}

.formula-info:hover::after {
    content: "1 Tola = 11.6638038 Grams | 1 Carat = 0.2 Grams | 1 Ounce = 28.3495 Grams | 1 Ratti = 0.1215 Grams | 1 Tael = 37.7994 Grams";
    position: absolute;
    bottom: 100%;
    left: 0;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    padding: 0.75rem;
    border-radius: var(--radius);
    width: 300px;
    z-index: 10;
    font-size: 0.75rem;
    box-shadow: var(--shadow);
}

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

.action-btn {
    padding: 0.5rem 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.875rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.action-btn:hover {
    background: var(--accent);
    border-color: var(--accent);
    transform: translateY(-2px);
}

.reverse-calculator {
    border-top: 1px solid var(--border);
    padding-top: 2rem;
}

.reverse-calculator h3 {
    margin-bottom: 1.5rem;
    font-size: 1.25rem;
    color: var(--text-secondary);
}

/* FAQ Styles with accordion animation */
.faq-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.faq-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
}

.faq-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 20px -5px rgba(0, 0, 0, 0.3);
}

.faq-item h3 {
    margin-bottom: 1rem;
    color: var(--accent);
    font-size: 1.125rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-item h3::after {
    content: '+';
    font-size: 1.5rem;
    transition: var(--transition);
}

.faq-item.active h3::after {
    content: '-';
    transform: rotate(180deg);
}

.faq-item p {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active p {
    max-height: 500px;
}

/* Blog Styles */
.blog-container {
    display: grid;
    gap: 2rem;
}

.blog-post {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.blog-post:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
}

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

.post-meta {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1rem;
    display: block;
}

.read-more {
    display: inline-block;
    margin-top: 1rem;
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.read-more:hover {
    color: var(--accent-hover);
    transform: translateX(5px);
}

/* Conversion table styles */
.conversion-table {
    margin: 2rem 0;
    overflow-x: auto;
}

.conversion-table h2 {
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
    color: var(--text-primary);
}

.conversion-table table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-card);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.conversion-table th,
.conversion-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.conversion-table th {
    background: var(--bg-secondary);
    font-weight: 600;
    color: var(--text-primary);
}

.conversion-table tr:last-child td {
    border-bottom: none;
}

.conversion-table tr:hover {
    background: rgba(59, 130, 246, 0.05);
}

/* SEO Keywords (visually hidden but accessible to crawlers) */
.seo-keywords {
    position: absolute;
    left: -10000px;
    top: auto;
    width: 1px;
    height: 1px;
    overflow: hidden;
}

/* Footer */
footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 2rem 0;
    margin-top: 3rem;
}

footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--text-primary);
}

/* Loading animation for async operations */
.loading-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--accent);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Dark mode toggle (optional feature) */
.dark-mode-toggle {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 999;
    transition: var(--transition);
}

.dark-mode-toggle:hover {
    transform: scale(1.1);
}

/* Toast notifications */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    z-index: 1000;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.toast.show {
    opacity: 1;
}

/* Advanced responsive design with mobile-first approach */
@media (max-width: 1200px) {
    .container {
        padding: 0 1.25rem;
    }
}

@media (max-width: 992px) {
    .hero h1 {
        font-size: 2.25rem;
    }
    
    .converter-card {
        padding: 1.75rem;
    }
}

@media (max-width: 768px) {
    :root {
        --radius: 0.75rem;
        --radius-2xl: 1.25rem;
    }
    
    html {
        font-size: 95%;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    /* Mobile navigation */
    .mobile-menu-btn {
        display: flex;
    }
    
    nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background: var(--bg-secondary);
        padding: 5rem 2rem 2rem;
        transition: right 0.3s ease;
        z-index: 999;
        box-shadow: -5px 0 25px rgba(0, 0, 0, 0.3);
    }
    
    nav.active {
        right: 0;
    }
    
    nav ul {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .mobile-menu-btn.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .mobile-menu-btn.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-menu-btn.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .unit-selectors {
        flex-direction: column;
        align-items: stretch;
        gap: 1rem;
    }
    
    .reverse-btn {
        align-self: center;
        margin: 0.5rem 0;
        transform: rotate(90deg);
    }
    
    .reverse-btn:hover {
        transform: rotate(270deg);
    }
    
    footer .container {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .conversion-table {
        font-size: 0.875rem;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.75rem;
    }
    
    .converter-card {
        padding: 1.5rem;
    }
    
    .precision-options {
        flex-direction: column;
    }
    
    .precision-btn {
        width: 100%;
        text-align: center;
    }
    
    .result-actions {
        flex-direction: column;
    }
    
    .action-btn {
        justify-content: center;
    }
    
    .blog-post {
        padding: 1.5rem;
    }
    
    .dark-mode-toggle {
        bottom: 1rem;
        right: 1rem;
        width: 45px;
        height: 45px;
    }
}

/* Reduced motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border: rgba(255, 255, 255, 0.8);
        --text-secondary: #ffffff;
    }
    
    .converter-card, .faq-item, .blog-post {
        border-width: 2px;
    }
}

/* Print Styles */
@media print {
    header, footer, .result-actions, .reverse-calculator, .tabs-container nav, .dark-mode-toggle {
        display: none !important;
    }
    
    .converter-card, .faq-item, .blog-post {
        border: none;
        box-shadow: none;
        background: white;
        color: black;
        break-inside: avoid;
    }
    
    .result {
        color: black;
        font-size: 1.25rem;
    }
    
    body {
        background: white;
        color: black;
    }
    
    a {
        color: black;
    }
}