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

:root {
    --bg-primary: #0a0e27;
    --bg-secondary: #121729;
    --bg-tertiary: #1a1f3a;
    --accent-primary: #4a90e2;
    --accent-secondary: #5c6bc0;
    --text-primary: #e8eaf6;
    --text-secondary: #b0b8d4;
    --text-muted: #7a82a0;
    --border-color: #2a3150;
    --card-bg: #151b33;
    --highlight: #667eea;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* Navigation */
.navbar {
    background: rgba(18, 23, 41, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    border-bottom: 1px solid var(--border-color);
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: bold;
    background: linear-gradient(135deg, var(--accent-primary), var(--highlight));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 1rem;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    transition: all 0.3s ease;
    font-size: 0.95rem;
}

.nav-links a:hover {
    color: var(--text-primary);
    background: var(--bg-tertiary);
    transform: translateY(-2px);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Sections */
.content-section {
    margin-bottom: 4rem;
    animation: fadeIn 0.6s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 3px solid var(--accent-primary);
    background: linear-gradient(135deg, var(--accent-primary), var(--highlight));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Question Blocks */
.question-block {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.question-block:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(74, 144, 226, 0.15);
    border-color: var(--accent-primary);
}

.question-block h2 {
    color: var(--accent-secondary);
    font-size: 1.4rem;
    margin-bottom: 1.5rem;
    padding-left: 1rem;
    border-left: 4px solid var(--accent-primary);
}

.answer {
    color: var(--text-secondary);
    font-size: 1.05rem;
}

.answer h3 {
    color: var(--text-primary);
    margin: 1.5rem 0 1rem 0;
    font-size: 1.3rem;
}

.answer h4 {
    color: var(--accent-secondary);
    margin: 1rem 0 0.5rem 0;
    font-size: 1.15rem;
}

.answer p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

.answer ul {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.answer ul li {
    margin-bottom: 0.7rem;
    line-height: 1.7;
}

.answer ul li strong {
    color: var(--accent-primary);
}

/* Tables */
.comparison-table,
.impact-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    background: var(--bg-tertiary);
    border-radius: 8px;
    overflow: hidden;
}

.comparison-table thead,
.impact-table thead {
    background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
}

.comparison-table th,
.impact-table th {
    padding: 1rem;
    text-align: left;
    color: white;
    font-weight: 600;
}

.comparison-table td,
.impact-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.comparison-table tbody tr:hover,
.impact-table tbody tr:hover {
    background: var(--card-bg);
}

/* Quality Cards */
.quality-card {
    background: var(--bg-tertiary);
    padding: 1.5rem;
    border-radius: 10px;
    margin: 1rem 0;
    border-left: 4px solid var(--accent-primary);
    transition: all 0.3s ease;
}

.quality-card:hover {
    transform: translateX(8px);
    border-left-color: var(--highlight);
    background: var(--card-bg);
}

.quality-card h3,
.quality-card h4 {
    color: var(--accent-primary);
    margin-bottom: 0.5rem;
}

.quality-card p {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.quality-card ul {
    margin-left: 1.5rem;
    margin-top: 0.5rem;
}

.quality-card ul li {
    color: var(--text-secondary);
    margin-bottom: 0.3rem;
}

/* Style Cards */
.style-card {
    background: var(--bg-tertiary);
    padding: 1.5rem;
    border-radius: 10px;
    margin: 1.5rem 0;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.style-card:hover {
    border-color: var(--accent-primary);
    box-shadow: 0 8px 24px rgba(74, 144, 226, 0.2);
    transform: translateY(-4px);
}

.style-card h3 {
    color: var(--highlight);
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.style-card p {
    color: var(--text-secondary);
    margin-bottom: 0.8rem;
}

.style-card ul {
    margin-left: 1.5rem;
}

.style-card ul li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

/* Example boxes */
.example {
    background: linear-gradient(135deg, rgba(74, 144, 226, 0.1), rgba(102, 126, 234, 0.1));
    border-left: 4px solid var(--accent-primary);
    padding: 1rem 1.5rem;
    margin: 1rem 0;
    border-radius: 6px;
    font-style: italic;
    color: var(--text-primary);
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    background: var(--bg-secondary);
    color: var(--text-muted);
    border-top: 1px solid var(--border-color);
    margin-top: 4rem;
}

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

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

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

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

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .question-block {
        padding: 1.5rem;
    }

    .question-block h2 {
        font-size: 1.2rem;
    }

    .nav-links {
        gap: 0.5rem;
    }

    .nav-links a {
        font-size: 0.85rem;
        padding: 0.4rem 0.8rem;
    }

    .comparison-table,
    .impact-table {
        font-size: 0.9rem;
    }

    .comparison-table th,
    .comparison-table td,
    .impact-table th,
    .impact-table td {
        padding: 0.7rem;
    }
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

/* Selection */
::selection {
    background: var(--accent-primary);
    color: white;
}