/* =====================================================
   Windowido - Modern Website Styles
   ===================================================== */

/* CSS Custom Properties */
:root {
    /* Colors - Teal/Cyan theme for window management */
    --color-primary: #0d9488;
    --color-primary-light: #14b8a6;
    --color-primary-dark: #0f766e;

    --color-secondary: #06b6d4;
    --color-accent: #8b5cf6;

    --color-success: #22c55e;
    --color-warning: #f59e0b;
    --color-error: #ef4444;

    /* Semantic Colors - Light Mode */
    --color-bg: #ffffff;
    --color-bg-secondary: #f8fafc;
    --color-bg-tertiary: #f1f5f9;

    --color-surface: #ffffff;
    --color-surface-elevated: #ffffff;

    --color-text: #0f172a;
    --color-text-secondary: #475569;
    --color-text-tertiary: #94a3b8;

    --color-border: #e2e8f0;
    --color-border-light: #f1f5f9;

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #0d9488 0%, #06b6d4 50%, #0ea5e9 100%);
    --gradient-secondary: linear-gradient(135deg, #14b8a6 0%, #0d9488 100%);
    --gradient-surface: linear-gradient(180deg, rgba(255,255,255,0.8) 0%, rgba(255,255,255,0.4) 100%);

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    --font-size-6xl: 3.75rem;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
    --shadow-glow: 0 0 40px -10px var(--color-primary);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
    --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

    /* Z-Index */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-fixed: 300;
    --z-modal: 400;
    --z-tooltip: 500;
}

/* Dark Mode */
[data-theme="dark"] {
    --color-bg: #0f0f23;
    --color-bg-secondary: #1a1a2e;
    --color-bg-tertiary: #16213e;

    --color-surface: rgba(26, 26, 46, 0.8);
    --color-surface-elevated: rgba(30, 30, 60, 0.9);

    --color-text: #f8fafc;
    --color-text-secondary: #cbd5e1;
    --color-text-tertiary: #64748b;

    --color-border: #334155;
    --color-border-light: #1e293b;

    --gradient-surface: linear-gradient(180deg, rgba(30,30,60,0.8) 0%, rgba(15,15,35,0.6) 100%);
}

/* =====================================================
   Base Styles
   ===================================================== */

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    overflow-x: hidden;
}

/* Background Elements */
.bg-gradient {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(13, 148, 136, 0.15), transparent),
        radial-gradient(ellipse 60% 40% at 100% 0%, rgba(6, 182, 212, 0.1), transparent),
        radial-gradient(ellipse 50% 30% at 0% 100%, rgba(14, 165, 233, 0.1), transparent);
    pointer-events: none;
    z-index: -3;
}

.bg-grid {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        linear-gradient(var(--color-border-light) 1px, transparent 1px),
        linear-gradient(90deg, var(--color-border-light) 1px, transparent 1px);
    background-size: 60px 60px;
    opacity: 0.5;
    pointer-events: none;
    z-index: -2;
}

[data-theme="dark"] .bg-grid {
    opacity: 0.15;
}

.bg-glow {
    position: fixed;
    top: 50%;
    left: 50%;
    width: 800px;
    height: 800px;
    transform: translate(-50%, -50%);
    background: radial-gradient(circle, rgba(13, 148, 136, 0.1) 0%, transparent 70%);
    pointer-events: none;
    z-index: -1;
    animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.5; transform: translate(-50%, -50%) scale(1); }
    50% { opacity: 0.8; transform: translate(-50%, -50%) scale(1.1); }
}

/* Container */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-text);
}

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

/* =====================================================
   Navigation
   ===================================================== */

.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-fixed);
    padding: var(--spacing-md) 0;
    transition: all var(--transition-base);
}

.nav.scrolled {
    background: var(--color-surface);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border-light);
    box-shadow: var(--shadow-sm);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: 700;
    font-size: var(--font-size-lg);
}

.logo-icon {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    color: white;
}

.logo-icon svg {
    width: 20px;
    height: 20px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-links a {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

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

.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.theme-toggle {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    background: var(--color-bg-secondary);
    border-color: var(--color-primary);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    color: var(--color-text-secondary);
}

.theme-toggle .moon-icon {
    display: none;
}

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

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

.lang-toggle {
    padding: 8px 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
}

.lang-toggle:hover {
    background: var(--color-bg-secondary);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
    background: none;
    border: none;
    cursor: pointer;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--color-text);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

/* =====================================================
   Buttons
   ===================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-family: inherit;
    font-size: var(--font-size-sm);
    font-weight: 600;
    border-radius: var(--radius-lg);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn svg {
    width: 18px;
    height: 18px;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md), 0 0 20px -5px var(--color-primary);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 30px -5px var(--color-primary);
}

.btn-secondary {
    background: var(--color-bg-tertiary);
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    background: var(--color-bg-secondary);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.btn-lg {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-base);
    border-radius: var(--radius-xl);
}

.btn-nav {
    padding: var(--spacing-sm) var(--spacing-md);
}

/* =====================================================
   Hero Section
   ===================================================== */

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: calc(80px + var(--spacing-3xl)) 0 var(--spacing-3xl);
    position: relative;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.hero-content {
    max-width: 600px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: var(--color-success);
    border-radius: var(--radius-full);
    animation: blink 2s ease-in-out infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    font-size: clamp(var(--font-size-4xl), 5vw, var(--font-size-6xl));
    font-weight: 800;
    margin-bottom: var(--spacing-lg);
    line-height: 1.1;
}

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-2xl);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.stat {
    text-align: center;
}

.stat-value {
    display: block;
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-text);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--color-border);
}

/* Hero Visual */
.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.device-mockup {
    position: relative;
    perspective: 1000px;
}

/* Mac Laptop Mockup */
.device-frame {
    width: 480px;
    height: 300px;
    background: linear-gradient(145deg, #1a1a2e 0%, #0f0f23 100%);
    border-radius: 12px 12px 0 0;
    padding: 8px 8px 0 8px;
    box-shadow:
        0 50px 100px -20px rgba(0, 0, 0, 0.5),
        inset 0 1px 0 rgba(255, 255, 255, 0.1);
    transform: rotateY(-5deg) rotateX(5deg);
    transition: transform var(--transition-slow);
    position: relative;
}

/* Mac notch/camera */
.device-frame::before {
    content: '';
    position: absolute;
    top: 4px;
    left: 50%;
    transform: translateX(-50%);
    width: 6px;
    height: 6px;
    background: #333;
    border-radius: 50%;
    z-index: 10;
}

/* Mac base/keyboard area */
.device-frame::after {
    content: '';
    position: absolute;
    bottom: -20px;
    left: -10px;
    right: -10px;
    height: 20px;
    background: linear-gradient(145deg, #2a2a3e 0%, #1f1f33 100%);
    border-radius: 0 0 8px 8px;
    box-shadow:
        0 10px 30px -10px rgba(0, 0, 0, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.05);
}

.device-frame:hover {
    transform: rotateY(0deg) rotateX(0deg);
}

.device-screen {
    width: 100%;
    height: 100%;
    background: var(--color-bg);
    border-radius: 8px 8px 0 0;
    overflow: hidden;
}

.app-preview {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.app-header {
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
}

.app-title {
    color: white;
    font-weight: 700;
    font-size: var(--font-size-lg);
}

.app-content {
    flex: 1;
    padding: var(--spacing-md);
    display: flex;
    flex-direction: row;
    gap: var(--spacing-md);
}

.app-content.window-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 1fr 1fr;
    gap: var(--spacing-sm);
}

.window-cell {
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md);
    border: 2px dashed var(--color-border);
    transition: all var(--transition-fast);
}

.window-cell.active {
    background: rgba(13, 148, 136, 0.2);
    border-color: var(--color-primary);
    border-style: solid;
}

.device-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 400px;
    height: 400px;
    transform: translate(-50%, -50%);
    background: radial-gradient(circle, rgba(13, 148, 136, 0.3) 0%, transparent 70%);
    filter: blur(40px);
    z-index: -1;
}

/* Floating Cards */
.floating-card {
    position: absolute;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--color-surface);
    backdrop-filter: blur(10px);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    font-size: var(--font-size-sm);
    font-weight: 500;
    animation: float 6s ease-in-out infinite;
}

.floating-card svg {
    width: 20px;
    height: 20px;
    color: var(--color-primary);
}

.floating-card.card-1 {
    top: 10%;
    right: -20px;
    animation-delay: 0s;
}

.floating-card.card-2 {
    bottom: 30%;
    left: -40px;
    animation-delay: 2s;
}

.floating-card.card-3 {
    bottom: 10%;
    right: 10%;
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

/* Scroll Indicator */
.hero-scroll {
    position: absolute;
    bottom: var(--spacing-xl);
    left: 50%;
    transform: translateX(-50%);
}

.scroll-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--color-text-tertiary);
    font-size: var(--font-size-sm);
    animation: bounce 2s ease-in-out infinite;
}

.scroll-indicator svg {
    width: 20px;
    height: 20px;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(5px); }
}

/* =====================================================
   Section Styles
   ===================================================== */

section {
    padding: var(--spacing-4xl) 0;
}

.section-header {
    text-align: center;
    max-width: 1000px;
    margin: 0 auto var(--spacing-3xl);
}

.section-badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    background: var(--color-primary);
    background: var(--gradient-primary);
    color: white;
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-md);
}

.section-title {
    font-size: clamp(var(--font-size-3xl), 4vw, var(--font-size-5xl));
    margin-bottom: var(--spacing-md);
}

.section-description {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
}

/* =====================================================
   Features Section
   ===================================================== */

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.feature-card {
    padding: var(--spacing-xl);
    background: var(--color-surface);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: var(--color-primary);
    box-shadow: var(--shadow-xl), var(--shadow-glow);
}

.feature-card.feature-highlight {
    grid-column: span 2;
    background: var(--gradient-surface);
    backdrop-filter: blur(10px);
}

.feature-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-md);
}

.feature-icon svg {
    width: 24px;
    height: 24px;
    color: white;
}

.feature-card h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    line-height: 1.6;
}

.feature-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.tag {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-weight: 500;
    color: var(--color-text-secondary);
}

/* =====================================================
   How It Works Section
   ===================================================== */

.how-it-works {
    background: var(--color-bg-secondary);
}

.steps {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
}

.step {
    position: relative;
    flex: 1;
    min-width: 280px;
    max-width: 350px;
    text-align: center;
}

.step-number {
    font-size: var(--font-size-6xl);
    font-weight: 800;
    color: var(--color-border);
    line-height: 1;
    margin-bottom: var(--spacing-md);
}

.step-content {
    padding: var(--spacing-xl);
    background: var(--color-surface);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-xl);
}

.step-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    margin: 0 auto var(--spacing-md);
}

.step-icon svg {
    width: 32px;
    height: 32px;
    color: white;
}

.step h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
}

.step p {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
}

.step-connector {
    display: none;
}

/* =====================================================
   Layouts Section
   ===================================================== */

.layouts {
    background: var(--color-bg);
}

.layouts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.layout-category {
    background: var(--color-surface);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
}

.layout-category h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
    color: var(--color-primary);
}

.layout-previews {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-sm);
}

.layout-preview {
    aspect-ratio: 16/10;
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md);
    padding: 4px;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.layout-preview:hover {
    background: var(--color-primary);
    transform: scale(1.05);
}

.preview-grid {
    width: 100%;
    height: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2px;
}

.preview-grid.rows {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 1fr;
}

.preview-grid.corners {
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 1fr 1fr;
}

.preview-grid.thirds {
    grid-template-columns: 1fr 1fr 1fr;
}

.preview-grid.grid3x2 {
    grid-template-columns: 1fr 1fr 1fr;
    grid-template-rows: 1fr 1fr;
}

.preview-grid.quarters {
    grid-template-columns: 1fr 1fr 1fr 1fr;
}

.preview-grid.fullscreen {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr;
}

.preview-grid.center {
    grid-template-columns: 1fr 2fr 1fr;
    grid-template-rows: 1fr 2fr 1fr;
}

.preview-grid.twothirds {
    grid-template-columns: 2fr 1fr;
}

.preview-grid.twothirds-right {
    grid-template-columns: 1fr 2fr;
}

.preview-grid.sixths {
    grid-template-columns: 1fr 1fr 1fr;
    grid-template-rows: 1fr 1fr;
}

.preview-cell {
    background: rgba(255, 255, 255, 0.3);
    border-radius: 2px;
}

.preview-cell.active {
    background: var(--color-primary);
}

.layout-preview:hover .preview-cell {
    background: rgba(255, 255, 255, 0.3);
}

.layout-preview:hover .preview-cell.active {
    background: white;
}

/* =====================================================
   Changelog Section
   ===================================================== */

.changelog {
    background: var(--color-bg-secondary);
}

.changelog-filters {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-2xl);
}

.filter-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    font-family: inherit;
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.filter-btn:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.filter-btn.active {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: white;
}

.filter-dot {
    width: 8px;
    height: 8px;
    border-radius: var(--radius-full);
}

.filter-dot.feature { background: #9333ea; }
.filter-dot.improvement { background: #3b82f6; }
.filter-dot.bugfix { background: #22c55e; }

.changelog-timeline {
    max-width: 800px;
    margin: 0 auto;
}

.version-entry {
    position: relative;
    padding-left: var(--spacing-2xl);
    padding-bottom: var(--spacing-2xl);
    border-left: 2px solid var(--color-border);
}

.version-entry:last-child {
    border-left: 2px solid transparent;
}

.version-dot {
    position: absolute;
    left: -9px;
    top: 0;
    width: 16px;
    height: 16px;
    background: var(--color-primary);
    border: 3px solid var(--color-bg-secondary);
    border-radius: var(--radius-full);
}

.version-header {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.version-number {
    font-size: var(--font-size-2xl);
    font-weight: 700;
}

.version-codename {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
}

.version-date {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.version-changes {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.change-item {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--color-surface);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-lg);
}

.change-type {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
    white-space: nowrap;
}

.change-type.feature {
    background: rgba(147, 51, 234, 0.1);
    color: #9333ea;
}

.change-type.improvement {
    background: rgba(59, 130, 246, 0.1);
    color: #3b82f6;
}

.change-type.bugfix {
    background: rgba(34, 197, 94, 0.1);
    color: #22c55e;
}

.change-content h4 {
    font-size: var(--font-size-base);
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.change-content p {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

/* =====================================================
   Download Section
   ===================================================== */

.download {
    padding: var(--spacing-4xl) 0;
}

.download-card {
    position: relative;
    padding: var(--spacing-3xl);
    background: var(--gradient-primary);
    border-radius: var(--radius-2xl);
    overflow: hidden;
}

.download-glow {
    position: absolute;
    top: -50%;
    right: -20%;
    width: 60%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.2) 0%, transparent 70%);
    pointer-events: none;
}

.download-content {
    position: relative;
    text-align: center;
    color: white;
}

.download-content h2 {
    font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-4xl));
    color: white;
    margin-bottom: var(--spacing-md);
}

.download-content > p {
    font-size: var(--font-size-lg);
    opacity: 0.9;
    margin-bottom: var(--spacing-2xl);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.download-buttons {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-2xl);
}

.download-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-xl);
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-xl);
    color: white;
    transition: all var(--transition-fast);
}

.download-btn:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-2px);
}

.download-btn svg {
    width: 32px;
    height: 32px;
}

.download-btn div {
    text-align: left;
}

.download-btn span {
    display: block;
    font-size: var(--font-size-xs);
    opacity: 0.8;
}

.download-btn strong {
    font-size: var(--font-size-lg);
}

.download-info {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--spacing-xl);
}

.download-info span {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-sm);
    opacity: 0.9;
}

.download-info svg {
    width: 18px;
    height: 18px;
}

/* =====================================================
   Footer
   ===================================================== */

.footer {
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border-light);
}

.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: var(--spacing-3xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: 700;
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
}

.footer-brand p {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    max-width: 300px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.footer-column h4 {
    font-size: var(--font-size-sm);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.footer-column a {
    display: block;
    padding: var(--spacing-xs) 0;
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--color-border-light);
}

.footer-bottom p {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

/* =====================================================
   Animations (AOS-like)
   ===================================================== */

[data-aos] {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-aos].aos-animate {
    opacity: 1;
    transform: translateY(0);
}

[data-aos="fade-up"] {
    transform: translateY(30px);
}

[data-aos="fade-left"] {
    transform: translateX(30px);
}

[data-aos="zoom-in"] {
    transform: scale(0.95);
}

/* =====================================================
   Responsive Design
   ===================================================== */

@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-stats {
        justify-content: center;
    }

    .hero-visual {
        display: none;
    }

    .feature-card.feature-highlight {
        grid-column: span 1;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        padding: var(--spacing-lg);
        background: var(--color-surface);
        backdrop-filter: blur(20px);
        border-bottom: 1px solid var(--color-border-light);
        gap: var(--spacing-md);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

    .btn-nav {
        display: none;
    }

    .hero {
        padding-top: calc(60px + var(--spacing-2xl));
    }

    .steps {
        flex-direction: column;
        align-items: center;
    }

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

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-brand {
        margin-bottom: var(--spacing-xl);
    }

    .footer-brand p {
        max-width: 100%;
    }

    .footer-logo {
        justify-content: center;
    }

    .footer-links {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }

    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }

    .download-buttons {
        flex-direction: column;
        align-items: center;
    }

    .download-btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    :root {
        --spacing-lg: 1rem;
        --spacing-xl: 1.5rem;
        --spacing-2xl: 2rem;
        --spacing-3xl: 3rem;
        --spacing-4xl: 4rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .stat-divider {
        width: 40px;
        height: 1px;
    }

    .hero-actions {
        flex-direction: column;
    }

    .hero-actions .btn {
        width: 100%;
        justify-content: center;
    }
}