/* Base Variables */
:root {
    /* Dark Theme (Default) */
    --bg-color: #0B0F19;
    --bg-color-secondary: #1A1F2E;
    --text-primary: #E2E8F0;
    --text-secondary: #94A3B8;
    --heading-color: #FFFFFF;
    
    --accent-primary: #6366F1;
    --accent-primary-hover: #4F46E5;
    --accent-secondary: #A855F7;
    
    --glass-bg: rgba(26, 31, 46, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    
    --card-bg: rgba(30, 41, 59, 0.5);
    
    --success: #10B981;
    --warning: #F59E0B;
    --info: #3B82F6;
    
    /* Effects */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Layout */
    --max-width: 1100px;
    --header-height: 80px;
}

/* Light Theme overrides */
[data-theme="light"] {
    --bg-color: #F8FAFC;
    --bg-color-secondary: #F1F5F9;
    --text-primary: #334155;
    --text-secondary: #64748B;
    --heading-color: #0F172A;
    
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.5);
    --glass-shadow: 0 8px 32px rgba(30, 41, 59, 0.05);
    
    --card-bg: rgba(255, 255, 255, 0.8);
    --warning: #D97706;
}

/* Reset & Global */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: calc(var(--header-height) + 20px);
}

body {
    font-family: 'Inter', sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-color);
    line-height: 1.7;
    overflow-x: hidden;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Outfit', sans-serif;
    color: var(--heading-color);
    margin-bottom: 1rem;
    font-weight: 700;
}

a {
    color: var(--accent-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--accent-secondary);
}

/* Scroll Progress */
.scroll-progress-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: transparent;
    z-index: 1000;
}

.scroll-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    width: 0%;
    transition: width 0.1s;
}

/* Background Abstract Shapes */
.bg-shape {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    z-index: -1;
    opacity: 0.4;
    animation: float 20s infinite ease-in-out alternate;
}

.shape-1 {
    top: -10%;
    right: -5%;
    width: 50vh;
    height: 50vh;
    background: var(--accent-primary);
    animation-delay: 0s;
}

.shape-2 {
    bottom: -10%;
    left: -10%;
    width: 60vh;
    height: 60vh;
    background: var(--accent-secondary);
    animation-delay: -5s;
}

.shape-3 {
    top: 40%;
    left: 40%;
    width: 40vh;
    height: 40vh;
    background: var(--info);
    opacity: 0.2;
    animation-delay: -10s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(50px, 30px) scale(1.1); }
    100% { transform: translate(-30px, 50px) scale(0.9); }
}

/* Header */
.glass-header {
    position: fixed;
    top: 0;
    width: 100%;
    height: var(--header-height);
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--glass-border);
    z-index: 100;
    transition: all var(--transition-normal);
}

.header-content {
    max-width: var(--max-width);
    margin: 0 auto;
    height: 100%;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: 'Outfit', sans-serif;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--heading-color);
}

.logo-icon {
    font-size: 1.8rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.theme-toggle {
    background: transparent;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition-fast), transform var(--transition-fast);
}

.theme-toggle:hover {
    background: var(--card-bg);
    transform: rotate(15deg);
}

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

/* Main Container */
.main-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: calc(var(--header-height) + 4rem) 2rem 4rem;
}

/* Hero Section */
.hero {
    text-align: center;
    margin-bottom: 4rem;
}

.hero-badge {
    display: inline-block;
    padding: 0.5rem 1.25rem;
    border-radius: 100px;
    background: rgba(99, 102, 241, 0.1);
    color: var(--accent-primary);
    font-weight: 600;
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(99, 102, 241, 0.2);
}

.hero h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
    background: linear-gradient(to right, var(--heading-color), var(--text-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero .subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.hero .subtitle strong {
    color: var(--heading-color);
}

.hero-desc {
    max-width: 700px;
    margin: 0 auto;
    font-size: 1.125rem;
    color: var(--text-primary);
}

/* Content Layout */
.content-wrapper {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 3rem;
    align-items: start;
}

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 3rem;
    box-shadow: var(--glass-shadow);
}

/* Table of Contents */
.toc {
    position: sticky;
    top: calc(var(--header-height) + 2rem);
    border-right: 1px solid var(--glass-border);
    padding-right: 1rem;
}

.toc h3 {
    font-size: 1.125rem;
    margin-bottom: 1.5rem;
    color: var(--heading-color);
}

.toc nav ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.toc nav a {
    color: var(--text-secondary);
    font-size: 0.95rem;
    display: block;
    padding: 0.5rem 0.75rem;
    border-radius: 8px;
    transition: all var(--transition-fast);
}

.toc nav a:hover,
.toc nav a.active {
    color: var(--accent-primary);
    background: var(--card-bg);
    padding-left: 1rem;
}

/* Policy Content */
.policy-section {
    margin-bottom: 4rem;
    scroll-margin-top: calc(var(--header-height) + 20px);
}

.policy-section h2 {
    font-size: 1.75rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--glass-border);
    margin-bottom: 1.5rem;
}

.policy-section p {
    margin-bottom: 1.25rem;
}

/* Custom Lists */
.feature-list {
    list-style: none;
    margin-bottom: 1.5rem;
}

.feature-list li {
    position: relative;
    padding-left: 2rem;
    margin-bottom: 0.75rem;
}

.feature-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    top: 0;
    color: var(--accent-primary);
    font-weight: bold;
}

.feature-list li span {
    background: var(--card-bg);
    padding: 0.5rem 1rem;
    border-radius: 8px;
    display: inline-block;
    border: 1px solid var(--glass-border);
    transition: transform var(--transition-fast), background var(--transition-fast);
}

.feature-list li span:hover {
    transform: translateX(5px);
    background: rgba(99, 102, 241, 0.1);
    border-color: rgba(99, 102, 241, 0.3);
}

/* Grid layout for "How we use" */
.grid-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1rem;
    margin: 1.5rem 0;
}

.grid-card {
    background: var(--card-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 1.25rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.grid-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-color: var(--accent-primary);
}

.grid-card .icon {
    font-size: 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
}

/* Alerts */
.alert {
    padding: 1.25rem;
    border-radius: 12px;
    margin: 1.5rem 0;
    display: flex;
    gap: 1rem;
    border: 1px solid;
}

.alert p { margin: 0; }

.alert-info {
    background: rgba(59, 130, 246, 0.1);
    border-color: rgba(59, 130, 246, 0.3);
    color: var(--text-primary);
}

.alert-info strong {
    color: var(--info);
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border-color: rgba(245, 158, 11, 0.3);
    color: var(--text-primary);
}

/* Tags */
.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin: 1.5rem 0;
}

.tag {
    background: var(--bg-color-secondary);
    border: 1px solid var(--glass-border);
    padding: 0.5rem 1rem;
    border-radius: 100px;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.tag:hover {
    background: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
}

/* Contact Card */
.contact-card {
    background: var(--bg-color-secondary);
    border: 1px dashed var(--glass-border);
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    margin-top: 1rem;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white !important;
    padding: 0.75rem 1.75rem;
    border-radius: 100px;
    font-weight: 600;
    margin-top: 1rem;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

/* Footer */
.site-footer {
    border-top: 1px solid var(--glass-border);
    background: var(--bg-color-secondary);
    padding: 3rem 2rem;
    text-align: center;
}

.footer-content {
    max-width: var(--max-width);
    margin: 0 auto;
}

.footer-logo {
    font-family: 'Outfit', sans-serif;
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--heading-color);
}

.footer-links {
    margin-top: 1rem;
    color: var(--text-secondary);
}

.footer-links a {
    color: var(--text-secondary);
    margin: 0 0.5rem;
}

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

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--glass-border);
    color: var(--heading-color);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--glass-shadow);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-normal);
    z-index: 100;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--accent-primary);
    color: white;
    transform: translateY(-3px);
}

/* Animations Tools */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive Design */
@media (max-width: 900px) {
    .content-wrapper {
        grid-template-columns: 1fr;
    }
    
    .toc {
        position: relative;
        top: 0;
        border-right: none;
        border-bottom: 1px solid var(--glass-border);
        padding-right: 0;
        padding-bottom: 1.5rem;
        margin-bottom: 2rem;
    }
    
    .toc ul {
        flex-direction: row;
        flex-wrap: wrap;
    }
}

@media (max-width: 600px) {
    .glass-panel {
        padding: 1.5rem;
    }
    
    .hero h1 {
        font-size: 2.2rem;
    }
    
    .grid-list {
        grid-template-columns: 1fr;
    }
}