/* ============================================
   CSS Variables & Design Tokens
   ============================================ */
:root {
    /* Colors */
    --color-primary: #6366f1;
    --color-primary-dark: #4f46e5;
    --color-primary-light: #818cf8;
    --color-secondary: #ec4899;
    --color-secondary-dark: #db2777;

    --color-bg: #0f0f1a;
    --color-bg-secondary: #1a1a2e;
    --color-bg-tertiary: #252542;
    --color-bg-card: rgba(30, 30, 50, 0.8);

    --color-text: #f8fafc;
    --color-text-secondary: #94a3b8;
    --color-text-muted: #64748b;

    --color-border: rgba(255, 255, 255, 0.1);
    --color-border-hover: rgba(255, 255, 255, 0.2);

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

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #ec4899 100%);
    --gradient-bg: linear-gradient(180deg, #0f0f1a 0%, #1a1a2e 100%);
    --gradient-card: linear-gradient(145deg, rgba(30, 30, 50, 0.9) 0%, rgba(20, 20, 40, 0.9) 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: 2rem;
    --font-size-4xl: 2.5rem;
    --font-size-5xl: 3.5rem;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;

    /* 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 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.3);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

/* ============================================
   Reset & Base Styles
   ============================================ */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    overflow-x: hidden;
}

/* Gradient Background */
.gradient-bg {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--color-bg);
    z-index: -2;
}

.gradient-bg::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 30%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
                radial-gradient(circle at 70% 70%, rgba(236, 72, 153, 0.1) 0%, transparent 50%);
    animation: gradientMove 20s ease-in-out infinite;
}

@keyframes gradientMove {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    25% { transform: translate(2%, 2%) rotate(1deg); }
    50% { transform: translate(0, 4%) rotate(0deg); }
    75% { transform: translate(-2%, 2%) rotate(-1deg); }
}

/* ============================================
   Typography
   ============================================ */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-text);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-xl); }

p {
    color: var(--color-text-secondary);
}

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

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

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

/* ============================================
   Header & Navigation
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: var(--space-4) var(--space-6);
    background: rgba(15, 15, 26, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
}

.nav {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-text);
}

.logo:hover {
    color: var(--color-text);
}

.logo-icon {
    font-size: var(--font-size-2xl);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-6);
}

.nav-link {
    color: var(--color-text-secondary);
    font-weight: 500;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-text);
    background: var(--color-bg-tertiary);
}

/* Language Switcher */
.lang-switcher {
    display: flex;
    gap: var(--space-2);
    margin-left: var(--space-4);
    padding-left: var(--space-4);
    border-left: 1px solid var(--color-border);
}

.lang-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-1);
    background: transparent;
    border: 2px solid transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    opacity: 0.6;
    transition: all var(--transition-fast);
}

.lang-btn:hover {
    opacity: 1;
}

.lang-btn.active {
    opacity: 1;
    border-color: var(--color-primary);
}

.lang-btn svg {
    display: block;
    border-radius: 2px;
}

/* ============================================
   Main Content
   ============================================ */
.main {
    padding-top: 80px;
    min-height: 100vh;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: 500;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--color-text);
    box-shadow: var(--shadow-md), 0 0 20px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 30px rgba(99, 102, 241, 0.4);
}

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

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

.btn-large {
    padding: var(--space-4) var(--space-8);
    font-size: var(--font-size-lg);
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-20) var(--space-6);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
    min-height: calc(100vh - 80px);
}

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

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: var(--space-6);
}

.hero-subtitle {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-8);
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: var(--space-4);
    flex-wrap: wrap;
}

.hero-visual {
    position: relative;
    height: 400px;
}

.floating-card {
    position: absolute;
    background: var(--gradient-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-lg);
    animation: float 6s ease-in-out infinite;
}

.floating-card .card-icon {
    font-size: 2.5rem;
    margin-bottom: var(--space-2);
}

.floating-card .card-label {
    font-weight: 600;
    color: var(--color-text);
}

.card-1 {
    top: 10%;
    left: 10%;
    animation-delay: 0s;
}

.card-2 {
    top: 5%;
    right: 15%;
    animation-delay: -1.5s;
}

.card-3 {
    bottom: 20%;
    left: 5%;
    animation-delay: -3s;
}

.card-4 {
    bottom: 10%;
    right: 10%;
    animation-delay: -4.5s;
}

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(2deg); }
}

/* ============================================
   Features Section
   ============================================ */
.features {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-20) var(--space-6);
}

.section-title {
    text-align: center;
    margin-bottom: var(--space-12);
    font-size: var(--font-size-3xl);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-6);
}

.feature-card {
    background: var(--gradient-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    text-align: center;
    transition: all var(--transition-base);
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--color-primary);
    box-shadow: var(--shadow-glow);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--space-4);
}

.feature-card h3 {
    margin-bottom: var(--space-3);
}

.feature-card p {
    font-size: var(--font-size-sm);
}

/* ============================================
   Categories Preview
   ============================================ */
.categories-preview {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-20) var(--space-6);
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-4);
    margin-bottom: var(--space-10);
}

.category-card {
    background: var(--gradient-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    display: flex;
    align-items: center;
    gap: var(--space-4);
    cursor: pointer;
    transition: all var(--transition-base);
}

.category-card:hover {
    border-color: var(--color-primary);
    transform: translateX(5px);
}

.category-icon {
    font-size: 2rem;
}

.category-info h4 {
    font-size: var(--font-size-base);
    margin-bottom: var(--space-1);
}

.category-count {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
}

.categories-cta {
    text-align: center;
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    padding: var(--space-12) var(--space-6);
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    font-size: var(--font-size-xl);
    font-weight: 700;
    margin-bottom: var(--space-4);
}

.footer-text {
    color: var(--color-text-muted);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 968px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        padding-top: var(--space-12);
    }

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

    .hero-title {
        font-size: var(--font-size-4xl);
    }

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

    .hero-visual {
        display: none;
    }
}

@media (max-width: 640px) {
    .header {
        padding: var(--space-3) var(--space-4);
    }

    .nav-links {
        gap: var(--space-2);
    }

    .nav-link {
        padding: var(--space-2);
        font-size: var(--font-size-sm);
    }

    .hero-title {
        font-size: var(--font-size-3xl);
    }

    .hero-subtitle {
        font-size: var(--font-size-base);
    }

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

    .btn {
        width: 100%;
    }

    .section-title {
        font-size: var(--font-size-2xl);
    }
}