:root {
    --primary-bg: #0a0a0a;
    --secondary-bg: #1a1a1a;
    --card-bg: rgba(26, 26, 26, 0.8);
    --border-color: #333333;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-tertiary: #06b6d4;
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --accent-error: #ef4444;
    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --gradient-secondary: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
    --gradient-tertiary: linear-gradient(135deg, #10b981 0%, #059669 100%);
    --gradient-warning: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
    --gradient-rainbow: linear-gradient(135deg, #6366f1 0%, #8b5cf6 25%, #06b6d4 50%, #10b981 75%, #f59e0b 100%);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.3);
    --container-padding: 2rem;
    --section-padding: 6rem 0;
    --card-padding: 2rem;
    --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;
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 50%;
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="light"] {
    --primary-bg: #ffffff;
    --secondary-bg: #f8fafc;
    --card-bg: rgba(255, 255, 255, 0.8);
    --border-color: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

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

.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--primary-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

    .loading-screen.hidden {
        opacity: 0;
        visibility: hidden;
    }

.loading-spinner {
    text-align: center;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--accent-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.bg-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    opacity: 0.1;
    background: radial-gradient(circle at 20% 20%, rgba(99, 102, 241, 0.3) 0%, transparent 40%), radial-gradient(circle at 80% 80%, rgba(139, 92, 246, 0.3) 0%, transparent 40%), radial-gradient(circle at 40% 60%, rgba(6, 182, 212, 0.3) 0%, transparent 40%);
    animation: backgroundFloat 20s ease-in-out infinite;
}

@keyframes backgroundFloat {
    0%, 100% {
        transform: translateY(0px) rotate(0deg);
    }

    33% {
        transform: translateY(-20px) rotate(120deg);
    }

    66% {
        transform: translateY(10px) rotate(240deg);
    }
}

.cursor-glow {
    position: fixed;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
    z-index: -1;
    transition: opacity var(--transition-fast);
    opacity: 0;
}

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(10, 10, 10, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 1rem 0;
    transition: all var(--transition-normal);
}

[data-theme="light"] .navbar {
    background: rgba(255, 255, 255, 0.9);
}

.navbar.scrolled {
    padding: 0.5rem 0;
    box-shadow: var(--shadow-lg);
}

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

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    font-weight: 700;
    font-size: var(--font-size-xl);
    color: var(--text-primary);
    transition: all var(--transition-normal);
}

    .logo:hover {
        transform: scale(1.05);
    }

.logo-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-right: 0.5rem;
}

.logo-full {
    display: none;
}

@media (min-width: 768px) {
    .logo-full {
        display: inline;
    }
}

.nav-links {
    display: flex;
    list-style: none;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: all var(--transition-normal);
    position: relative;
}

    .nav-link::after {
        content: '';
        position: absolute;
        bottom: -4px;
        left: 0;
        width: 0;
        height: 2px;
        background: var(--gradient-primary);
        transition: width var(--transition-normal);
    }

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

        .nav-link:hover::after,
        .nav-link.active::after {
            width: 100%;
        }

.theme-toggle {
    background: none;
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
}

    .theme-toggle:hover {
        border-color: var(--accent-primary);
        transform: rotate(180deg);
        box-shadow: var(--shadow-glow);
    }

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    gap: 4px;
}

.hamburger-line {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    transition: all var(--transition-normal);
}

.mobile-menu-btn.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

.mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(20px);
    z-index: 999;
    transform: translateY(-100%);
    transition: transform var(--transition-normal);
}

    .mobile-menu-overlay.active {
        transform: translateY(0);
    }

.mobile-menu-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    gap: 2rem;
}

.mobile-nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-size: var(--font-size-2xl);
    font-weight: 600;
    transition: all var(--transition-normal);
}

    .mobile-nav-link:hover {
        background: var(--gradient-primary);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        transform: scale(1.1);
    }

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.section-padding {
    padding: var(--section-padding);
}

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

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-lg);
    font-weight: 600;
    font-size: var(--font-size-sm);
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

    .btn::before {
        content: '';
        position: absolute;
        top: 0;
        left: -100%;
        width: 100%;
        height: 100%;
        background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
        transition: left var(--transition-slow);
    }

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

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    border: 2px solid transparent;
}

    .btn-primary:hover {
        transform: translateY(-2px);
        box-shadow: var(--shadow-glow);
    }

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

    .btn-secondary:hover {
        border-color: var(--accent-primary);
        background: var(--card-bg);
        transform: translateY(-2px);
    }

.btn-large {
    padding: 1rem 2rem;
    font-size: var(--font-size-base);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

.scroll-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border: none;
    border-radius: var(--radius-full);
    color: white;
    cursor: pointer;
    transition: all var(--transition-normal);
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transform: scale(0);
}

    .scroll-to-top.visible {
        opacity: 1;
        visibility: visible;
        transform: scale(1);
    }

    .scroll-to-top:hover {
        transform: scale(1.1);
        box-shadow: var(--shadow-glow);
    }

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: var(--font-size-4xl);
    font-weight: 800;
    margin-bottom: 1rem;
    position: relative;
}

.title-number {
    color: var(--accent-primary);
    font-size: var(--font-size-lg);
    font-weight: 600;
    display: block;
    margin-bottom: 0.5rem;
}

.section-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

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

@media (max-width: 1024px) {
    :root {
        --container-padding: 1.5rem;
        --section-padding: 4rem 0;
    }

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

@media (max-width: 768px) {
    :root {
        --container-padding: 1rem;
        --section-padding: 3rem 0;
    }

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

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

@media (max-width: 480px) {
    .btn {
        padding: 0.5rem 1rem;
        font-size: var(--font-size-xs);
    }

    .btn-large {
        padding: 0.75rem 1.5rem;
        font-size: var(--font-size-sm);
    }
}