@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

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

:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --primary-light: #60a5fa;
    --accent: #8b5cf6;
    --text: #0f172a;
    --text-light: #64748b;
    --bg: #ffffff;
    --bg-gray: #f8fafc;
    --bg-card: #ffffff;
    --border: #e2e8f0;
    --shadow: rgba(15, 23, 42, 0.08);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg-gray);
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 1.25rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    font-size: 1.75rem;
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: 0.25rem;
    font-weight: 500;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

nav a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    font-size: 0.9375rem;
    transition: color 0.2s;
    position: relative;
}

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

nav a.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
}

/* Hero */
.hero {
    background: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    color: white;
    padding: 5rem 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" xmlns="http://www.w3.org/2000/svg"><rect width="60" height="60" fill="none"/><circle cx="30" cy="30" r="1.5" fill="rgba(255,255,255,0.1)"/></svg>');
    opacity: 0.3;
}

.hero .container {
    position: relative;
}

.hero h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
    letter-spacing: -0.03em;
}

.hero p {
    font-size: 1.25rem;
    opacity: 0.95;
    font-weight: 400;
}

/* Cheatsheets Grid */
.cheatsheets {
    padding: 5rem 0;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 1px 3px var(--shadow);
}

.card:hover {
    box-shadow: 0 20px 40px var(--shadow);
    transform: translateY(-4px);
    border-color: var(--primary-light);
}

.card-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: inline-block;
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text);
    font-weight: 600;
    letter-spacing: -0.01em;
}

.card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    font-size: 0.9375rem;
    line-height: 1.6;
}

.btn {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 0.75rem 1.75rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9375rem;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
}

.btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

/* Features */
.features {
    background: var(--bg);
    padding: 5rem 0;
    border-top: 1px solid var(--border);
}

.features h2 {
    text-align: center;
    font-size: 2.25rem;
    margin-bottom: 3.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 3rem;
}

.feature {
    text-align: center;
}

.feature h3 {
    font-size: 1.375rem;
    margin-bottom: 0.75rem;
    font-weight: 600;
}

.feature p {
    color: var(--text-light);
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* Cheat Sheet Pages */
.cheatsheet-page {
    padding: 4rem 0;
    background: var(--bg-gray);
}

.cheatsheet-header {
    text-align: center;
    margin-bottom: 3.5rem;
}

.cheatsheet-header h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
    letter-spacing: -0.03em;
}

.cheatsheet-header p {
    font-size: 1.25rem;
    color: var(--text-light);
    font-weight: 500;
}

.section {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 2.5rem;
    margin-bottom: 2rem;
    box-shadow: 0 1px 3px var(--shadow);
}

.section h2 {
    font-size: 1.875rem;
    margin-bottom: 1.75rem;
    color: var(--primary);
    font-weight: 600;
    letter-spacing: -0.01em;
}

.shortcut-table,
.command-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    margin-top: 1rem;
}

.shortcut-table th,
.shortcut-table td,
.command-table th,
.command-table td {
    text-align: left;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
}

.shortcut-table th,
.command-table th {
    background: var(--bg-gray);
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-light);
}

.shortcut-table tbody tr:hover,
.command-table tbody tr:hover {
    background: var(--bg-gray);
}

.shortcut-table code,
.command-table code {
    background: var(--bg-gray);
    padding: 0.375rem 0.75rem;
    border-radius: 6px;
    font-family: 'SF Mono', 'Monaco', 'Cascadia Code', 'Courier New', monospace;
    font-size: 0.875rem;
    border: 1px solid var(--border);
    color: var(--primary-dark);
    font-weight: 500;
}

/* About & Content Pages */
.content-page {
    padding: 4rem 0;
    background: var(--bg-gray);
}

.content-page .container {
    max-width: 800px;
}

.content-page h1 {
    font-size: 3rem;
    margin-bottom: 2rem;
    font-weight: 700;
    letter-spacing: -0.03em;
}

.content-page h2 {
    font-size: 1.875rem;
    margin: 2.5rem 0 1rem;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.content-page p {
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

/* Footer */
footer {
    background: var(--text);
    color: white;
    padding: 3rem 0;
    text-align: center;
    margin-top: 5rem;
    border-top: 4px solid var(--primary);
}

footer p {
    margin: 0.5rem 0;
    opacity: 0.9;
}

footer a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.2s;
}

footer a:hover {
    opacity: 0.8;
}

/* Responsive */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        gap: 1rem;
    }

    nav ul {
        gap: 1.5rem;
    }

    .hero h2 {
        font-size: 2.25rem;
    }

    .hero p {
        font-size: 1.125rem;
    }

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

    .cheatsheet-header h1 {
        font-size: 2.25rem;
    }
    
    .section {
        padding: 1.5rem;
    }
    
    .shortcut-table th,
    .shortcut-table td,
    .command-table th,
    .command-table td {
        padding: 0.75rem 0.5rem;
        font-size: 0.875rem;
    }
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 1.5rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    font-size: 1.8rem;
    color: var(--primary);
    font-weight: 700;
}

.tagline {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: 0.25rem;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

nav a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    transition: color 0.2s;
}

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

/* Hero */
.hero {
    background: linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero p {
    font-size: 1.25rem;
    opacity: 0.95;
}

/* Cheatsheets Grid */
.cheatsheets {
    padding: 4rem 0;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 2rem;
    transition: all 0.3s;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.card:hover {
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    transform: translateY(-2px);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text);
}

.card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.btn {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 500;
    transition: background 0.2s;
}

.btn:hover {
    background: var(--primary-dark);
}

/* Features */
.features {
    background: var(--bg-gray);
    padding: 4rem 0;
}

.features h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature {
    text-align: center;
}

.feature h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.feature p {
    color: var(--text-light);
}

/* Cheat Sheet Pages */
.cheatsheet-page {
    padding: 3rem 0;
}

.cheatsheet-header {
    text-align: center;
    margin-bottom: 3rem;
}

.cheatsheet-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.cheatsheet-header p {
    font-size: 1.125rem;
    color: var(--text-light);
}

.section {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 2rem;
    margin-bottom: 2rem;
}

.section h2 {
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    color: var(--primary);
}

.shortcut-table,
.command-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.shortcut-table th,
.shortcut-table td,
.command-table th,
.command-table td {
    text-align: left;
    padding: 0.75rem;
    border-bottom: 1px solid var(--border);
}

.shortcut-table th,
.command-table th {
    background: var(--bg-gray);
    font-weight: 600;
}

.shortcut-table code,
.command-table code {
    background: var(--bg-gray);
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-family: "Monaco", "Courier New", monospace;
    font-size: 0.9rem;
}

/* About & Contact */
.content-page {
    padding: 3rem 0;
}

.content-page h1 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

.content-page p {
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.contact-form {
    max-width: 600px;
    margin: 2rem auto;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 1rem;
    font-family: inherit;
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

/* Footer */
footer {
    background: var(--text);
    color: white;
    padding: 2rem 0;
    text-align: center;
    margin-top: 4rem;
}

footer a {
    color: white;
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        gap: 1rem;
    }

    nav ul {
        gap: 1rem;
    }

    .hero h2 {
        font-size: 2rem;
    }

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