/* ===== CSS Variables ===== */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #10b981;
    --accent: #f59e0b;
    --dark: #0f172a;
    --dark-light: #1e293b;
    --gray-900: #111827;
    --gray-800: #1f2937;
    --gray-700: #374151;
    --gray-600: #4b5563;
    --gray-500: #6b7280;
    --gray-400: #9ca3af;
    --gray-300: #d1d5db;
    --gray-200: #e5e7eb;
    --gray-100: #f3f4f6;
    --white: #ffffff;
    --success: #10b981;
    
    --gradient-1: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 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), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

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

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

body {
    font-family: var(--font-sans);
    background: var(--dark);
    color: var(--gray-300);
    line-height: 1.7;
    overflow-x: hidden;
}

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

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

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1rem 0;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--gray-800);
}

.nav-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--white);
    text-decoration: none;
}

.nav-logo:hover {
    text-decoration: none;
    color: var(--white);
}

.logo-icon {
    font-size: 1.25rem;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--gray-300);
    background: var(--gray-800);
    border-radius: var(--radius-md);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.nav-link:hover {
    color: var(--white);
    background: var(--gray-700);
    text-decoration: none;
}

/* ===== Hero Section ===== */
.hero {
    position: relative;
    padding: 8rem 1.5rem 4rem;
    text-align: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(99, 102, 241, 0.3), transparent),
        radial-gradient(ellipse 60% 40% at 80% 60%, rgba(139, 92, 246, 0.15), transparent);
    z-index: -1;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.3);
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-light);
    margin-bottom: 1.5rem;
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 4rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 0.75rem;
}

.gradient-text {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.125rem, 3vw, 1.5rem);
    font-weight: 500;
    color: var(--gray-400);
}

/* ===== Main Content Wrapper ===== */
.content-wrapper {
    max-width: 900px;
    margin: 0 auto;
    padding: 3rem 1.5rem 6rem;
}

.loading {
    text-align: center;
    padding: 4rem;
    color: var(--gray-500);
}

/* ===== Markdown Body Styles ===== */
.markdown-body {
    color: var(--gray-300);
    font-size: 1rem;
    line-height: 1.8;
}

/* Headings */
.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4,
.markdown-body h5,
.markdown-body h6 {
    color: var(--white);
    font-weight: 700;
    line-height: 1.3;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
}

.markdown-body h1 {
    font-size: 2.25rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--gray-800);
    margin-top: 0;
}

.markdown-body h2 {
    font-size: 1.75rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--gray-800);
}

.markdown-body h3 {
    font-size: 1.375rem;
    color: var(--primary-light);
}

.markdown-body h4 {
    font-size: 1.125rem;
}

/* Paragraphs and text */
.markdown-body p {
    margin-bottom: 1.25rem;
}

.markdown-body strong {
    color: var(--white);
    font-weight: 600;
}

.markdown-body em {
    color: var(--gray-400);
}

/* Links */
.markdown-body a {
    color: var(--primary-light);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: all var(--transition-fast);
}

.markdown-body a:hover {
    color: var(--primary);
    border-bottom-color: var(--primary);
    text-decoration: none;
}

/* Lists */
.markdown-body ul,
.markdown-body ol {
    margin-bottom: 1.25rem;
    padding-left: 1.5rem;
}

.markdown-body li {
    margin-bottom: 0.5rem;
}

.markdown-body li::marker {
    color: var(--primary-light);
}

/* Code */
.markdown-body code {
    font-family: var(--font-mono);
    font-size: 0.875em;
    background: var(--gray-800);
    color: var(--primary-light);
    padding: 0.2em 0.4em;
    border-radius: var(--radius-sm);
}

.markdown-body pre {
    background: var(--gray-900);
    border: 1px solid var(--gray-800);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    overflow-x: auto;
    margin-bottom: 1.5rem;
}

.markdown-body pre code {
    background: none;
    padding: 0;
    font-size: 0.875rem;
    color: var(--gray-300);
}

/* Tables */
.markdown-body table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    background: var(--dark-light);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.markdown-body th,
.markdown-body td {
    padding: 0.875rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--gray-800);
}

.markdown-body th {
    background: var(--gray-900);
    color: var(--white);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.8rem;
    letter-spacing: 0.5px;
}

.markdown-body tr:last-child td {
    border-bottom: none;
}

.markdown-body tr:hover td {
    background: rgba(99, 102, 241, 0.05);
}

/* Images */
.markdown-body img {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius-lg);
    margin: 1.5rem 0;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--gray-800);
}

/* Blockquotes */
.markdown-body blockquote {
    border-left: 4px solid var(--primary);
    background: var(--dark-light);
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    color: var(--gray-400);
}

.markdown-body blockquote p:last-child {
    margin-bottom: 0;
}

/* Horizontal rules */
.markdown-body hr {
    border: none;
    height: 1px;
    background: var(--gray-800);
    margin: 3rem 0;
}

/* Task lists */
.markdown-body input[type="checkbox"] {
    margin-right: 0.5rem;
    accent-color: var(--primary);
}

/* Hide the GitHub classroom badge */
.markdown-body > p:first-child a img[src*="classroom.github.com"] {
    display: none;
}

.markdown-body > p:first-child:has(a img[src*="classroom.github.com"]) {
    display: none;
}

/* Style the first image badge link to be hidden */
.markdown-body > p:first-of-type > a:first-child:has(img) {
    display: none;
}

/* ===== Footer ===== */
.footer {
    border-top: 1px solid var(--gray-800);
    padding: 2rem 1.5rem;
    text-align: center;
    background: var(--dark-light);
}

.footer-content p {
    color: var(--gray-500);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.team-names {
    color: var(--gray-400);
    font-weight: 500;
}

/* ===== Back to Top Button ===== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: var(--white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-lg);
    z-index: 100;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

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

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .hero {
        padding: 7rem 1rem 3rem;
    }
    
    .content-wrapper {
        padding: 2rem 1rem 4rem;
    }
    
    .markdown-body table {
        display: block;
        overflow-x: auto;
        white-space: nowrap;
    }
    
    .markdown-body h1 {
        font-size: 1.75rem;
    }
    
    .markdown-body h2 {
        font-size: 1.5rem;
    }
    
    .back-to-top {
        bottom: 1rem;
        right: 1rem;
        width: 44px;
        height: 44px;
    }
}

@media (max-width: 480px) {
    .nav-container {
        padding: 0 1rem;
    }
    
    .nav-logo span:not(.logo-icon) {
        display: none;
    }
    
    .hero-badge {
        font-size: 0.75rem;
        padding: 0.375rem 0.75rem;
    }
}

/* ===== Scrollbar Styling ===== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--dark);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-700);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-600);
}

/* ===== Selection Styling ===== */
::selection {
    background: rgba(99, 102, 241, 0.3);
    color: var(--white);
}