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

:root {
    --bg-primary: #0a0e27;
    --bg-secondary: #141b3d;
    --bg-card: #1a2347;
    --accent-cyan: #00d9ff;
    --accent-green: #00ff88;
    --accent-purple: #9d4edd;
    --accent-red: #ff006e;
    --accent-orange: #ffaa00;
    --text-primary: #e8f1ff;
    --text-muted: #8b9dc3;
    --border: #2a3f6e;
}

body {
    font-family: 'Space Mono', monospace;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    background-image:
        radial-gradient(circle at 20% 80%, rgba(157, 78, 221, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(0, 217, 255, 0.1) 0%, transparent 50%);
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    text-align: center;
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--border);
}

h1 {
    font-family: 'JetBrains Mono', monospace;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
}

.subtitle {
    color: var(--text-muted);
    font-size: 0.9rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.mode-selector {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.mode-btn {
    padding: 1rem 2rem;
    border: 2px solid var(--border);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 12px;
    font-family: 'Space Mono', monospace;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.mode-btn:hover {
    border-color: var(--accent-cyan);
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0, 217, 255, 0.3);
}

.mode-btn.active {
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
    border-color: var(--accent-cyan);
    color: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.mode-stat {
    display: none;
}

body[data-mode="flashcard"] .flashcard-stat {
    display: block;
}

body[data-mode="port-to-service"] .quiz-stat,
body[data-mode="service-to-port"] .quiz-stat {
    display: block;
}

body[data-mode="mock-exam"] .exam-stat {
    display: block;
}

body[data-mode="cidr-quiz"] .cidr-quiz-stat {
    display: block;
}

body[data-mode="encryption-quiz"] .encryption-quiz-stat {
    display: block;
}

body[data-mode="osi-quiz"] .osi-quiz-stat {
    display: block;
}

body[data-mode="nmap-quiz"] .nmap-quiz-stat {
    display: block;
}

.stat-card {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    text-align: center;
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-2px);
    border-color: var(--accent-cyan);
    box-shadow: 0 4px 20px rgba(0, 217, 255, 0.2);
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    font-family: 'JetBrains Mono', monospace;
    margin-bottom: 0.25rem;
}

.stat-label {
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.controls {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

body[data-mode="mock-exam"] .controls,
body[data-mode="cidr-quiz"] .controls,
body[data-mode="encryption-quiz"] .controls,
body[data-mode="osi-quiz"] .controls,
body[data-mode="nmap-quiz"] .controls {
    display: none;
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-family: 'Space Mono', monospace;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 700;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0, 217, 255, 0.4);
}

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

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

.btn-danger {
    background: linear-gradient(135deg, #ff006e, #c1121f);
    color: white;
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(255, 0, 110, 0.4);
}

.danger-zone {
    margin-top: 4rem;
    padding: 2rem;
    border: 2px solid var(--accent-red);
    border-radius: 12px;
    background: rgba(255, 0, 110, 0.05);
    text-align: center;
}

.danger-zone h3 {
    color: var(--accent-red);
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
}

.danger-zone p {
    color: var(--text-muted);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

select {
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    border-radius: 8px;
    font-family: 'Space Mono', monospace;
    font-size: 0.9rem;
    cursor: pointer;
    flex: 1;
    min-width: 200px;
}

select:focus {
    outline: none;
    border-color: var(--accent-cyan);
}

select optgroup {
    color: var(--accent-cyan);
    font-style: normal;
    font-weight: 700;
    background: var(--bg-primary);
}

select optgroup option {
    color: var(--text-primary);
    font-weight: 400;
    background: var(--bg-secondary);
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-secondary);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 2rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
    transition: width 0.3s ease;
}

.complete-screen {
    text-align: center;
    padding: 4rem 2rem;
    background: var(--bg-card);
    border-radius: 16px;
    border: 2px solid var(--border);
}

.complete-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.complete-screen h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.user-menu {
    position: relative;
    margin-left: auto;
}

.user-email {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-right: 1rem;
}

.logout-btn {
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-primary);
    cursor: pointer;
    font-family: 'Space Mono', monospace;
    font-size: 0.85rem;
    transition: all 0.2s ease;
}

.logout-btn:hover {
    border-color: var(--accent-red);
    color: var(--accent-red);
}

body[data-mode="analytics"] .stats-grid,
body[data-mode="analytics"] .progress-bar,
body[data-mode="analytics"] .controls {
    display: none;
}

body[data-mode="cidr-quiz"] .progress-bar,
body[data-mode="encryption-quiz"] .progress-bar,
body[data-mode="osi-quiz"] .progress-bar,
body[data-mode="nmap-quiz"] .progress-bar {
    display: none;
}

body[data-mode="reference"] .stats-grid,
body[data-mode="reference"] .progress-bar,
body[data-mode="reference"] .controls {
    display: none;
}

@media (max-width: 768px) {
    h1 {
        font-size: 1.75rem;
    }
}