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

:root {
    --primary: #00d4ff;
    --primary-dim: #0088aa;
    --accent: #ff6b35;
    --danger: #ff3355;
    --success: #00ff88;
    --warning: #ffaa00;
    --shield-color: #00aaff;
    --health-color: #ff4466;
    --energy-color: #ffcc00;
    --crystal-color: #00ffcc;
    --bg-dark: #0a0e1a;
    --bg-panel: rgba(10, 14, 30, 0.85);
    --border-color: rgba(0, 212, 255, 0.3);
    --text: #e0e8ff;
    --text-dim: #7888aa;
    --glass: rgba(10, 20, 40, 0.7);
    --glass-border: rgba(0, 180, 255, 0.2);
}

html, body {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background: var(--bg-dark);
    font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    color: var(--text);
    user-select: none;
    -webkit-user-select: none;
    touch-action: none;
}

canvas#gameCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    display: block;
    z-index: 0;
}

.screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 100;
}

.screen.active {
    display: flex;
}

.menu-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(ellipse at 50% 30%, rgba(0, 40, 80, 0.6) 0%, rgba(10, 14, 26, 0.95) 70%);
    z-index: -1;
}

.overlay-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(5, 8, 18, 0.8);
    z-index: -1;
}

.menu-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
    padding: 40px;
    max-height: 90vh;
}

.menu-content.compact {
    gap: 16px;
    padding: 30px;
}

.menu-content.scrollable {
    overflow-y: auto;
    max-width: 700px;
    width: 90%;
}

.title-group {
    text-align: center;
    margin-bottom: 10px;
}

.game-title {
    font-size: 72px;
    font-weight: 900;
    letter-spacing: 12px;
    color: #fff;
    text-shadow: 0 0 40px rgba(0, 180, 255, 0.5), 0 0 80px rgba(0, 100, 200, 0.3);
    line-height: 1;
}

.title-accent {
    color: var(--primary);
    text-shadow: 0 0 30px rgba(0, 212, 255, 0.6), 0 0 60px rgba(0, 150, 255, 0.4);
}

.game-subtitle {
    font-size: 16px;
    letter-spacing: 8px;
    color: var(--text-dim);
    margin-top: 8px;
}

.screen-title {
    font-size: 36px;
    font-weight: 700;
    letter-spacing: 4px;
    color: var(--primary);
    text-shadow: 0 0 20px rgba(0, 180, 255, 0.3);
    margin-bottom: 10px;
    text-align: center;
}

.gameover-title {
    color: var(--danger);
    text-shadow: 0 0 20px rgba(255, 50, 80, 0.4);
}

.menu-buttons {
    display: flex;
    flex-direction: column;
    gap: 12px;
    width: 280px;
}

.menu-stats {
    font-size: 14px;
    color: var(--text-dim);
    letter-spacing: 2px;
    margin-top: 10px;
}

.btn {
    padding: 14px 32px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 600;
    letter-spacing: 3px;
    cursor: pointer;
    transition: all 0.2s ease;
    text-transform: uppercase;
    position: relative;
    overflow: hidden;
}

.btn::after {
    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 0.4s;
}

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

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #0088cc);
    color: #001a22;
    box-shadow: 0 0 20px rgba(0, 180, 255, 0.3);
}

.btn-primary:hover {
    transform: scale(1.03);
    box-shadow: 0 0 30px rgba(0, 180, 255, 0.5);
}

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

.btn-secondary:hover {
    background: rgba(0, 180, 255, 0.15);
    border-color: var(--primary);
}

.btn-danger {
    background: rgba(255, 50, 80, 0.15);
    color: var(--danger);
    border: 1px solid rgba(255, 50, 80, 0.3);
}

.btn-danger:hover {
    background: rgba(255, 50, 80, 0.25);
}

.btn-back {
    padding: 10px 24px;
    background: transparent;
    color: var(--text-dim);
    border: 1px solid rgba(255,255,255,0.15);
    border-radius: 6px;
    font-size: 14px;
    letter-spacing: 2px;
    cursor: pointer;
    margin-top: 10px;
}

.btn-back:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.gameover-stats {
    width: 300px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-bottom: 10px;
}

.stat-row {
    display: flex;
    justify-content: space-between;
    padding: 6px 12px;
    background: rgba(255,255,255,0.03);
    border-radius: 4px;
    font-size: 14px;
    letter-spacing: 1px;
}

.stat-row span:last-child {
    color: var(--primary);
    font-weight: 600;
}

.stat-row.highlight {
    border-top: 1px solid var(--border-color);
    margin-top: 4px;
    padding-top: 10px;
}

.stat-row.highlight span:last-child {
    color: var(--warning);
}

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

.respawn-label {
    font-size: 18px;
    letter-spacing: 4px;
    color: var(--text-dim);
    margin-bottom: 16px;
}

.respawn-count {
    font-size: 72px;
    font-weight: 900;
    color: var(--primary);
    text-shadow: 0 0 30px rgba(0, 180, 255, 0.5);
}

.settings-list {
    width: 320px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.setting-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 16px;
    background: rgba(255,255,255,0.03);
    border-radius: 6px;
    border: 1px solid rgba(255,255,255,0.05);
}

.setting-row span {
    font-size: 14px;
    letter-spacing: 1px;
}

.toggle-btn {
    padding: 6px 18px;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 4px;
    background: transparent;
    color: var(--text-dim);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 2px;
    cursor: pointer;
    transition: all 0.2s;
}

.toggle-btn.active {
    background: rgba(0, 212, 255, 0.15);
    border-color: var(--primary);
    color: var(--primary);
}

.setting-select {
    padding: 6px 12px;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 4px;
    background: var(--bg-dark);
    color: var(--text);
    font-size: 12px;
    letter-spacing: 1px;
    cursor: pointer;
}

.setting-select:focus {
    outline: none;
    border-color: var(--primary);
}

.mode-cards {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
    max-width: 800px;
}

.mode-card {
    width: 220px;
    padding: 24px 16px;
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    text-align: center;
    cursor: pointer;
    transition: all 0.25s;
}

.mode-card:hover {
    border-color: var(--primary);
    background: rgba(0, 180, 255, 0.1);
    transform: translateY(-3px);
}

.mode-icon {
    font-size: 36px;
    margin-bottom: 10px;
    color: var(--primary);
}

.mode-card h3 {
    font-size: 16px;
    letter-spacing: 2px;
    margin-bottom: 8px;
}

.mode-card p {
    font-size: 12px;
    color: var(--text-dim);
    line-height: 1.5;
}

.help-grid {
    display: flex;
    flex-direction: column;
    gap: 24px;
    margin-bottom: 20px;
}

.help-section h3 {
    font-size: 16px;
    letter-spacing: 3px;
    color: var(--primary);
    margin-bottom: 12px;
    padding-bottom: 6px;
    border-bottom: 1px solid var(--border-color);
}

.help-item {
    font-size: 13px;
    color: var(--text-dim);
    margin-bottom: 6px;
    padding-left: 8px;
}

.help-step {
    font-size: 13px;
    color: var(--text-dim);
    margin-bottom: 6px;
    padding-left: 8px;
}

.key {
    display: inline-block;
    padding: 2px 8px;
    background: rgba(0, 180, 255, 0.1);
    border: 1px solid rgba(0, 180, 255, 0.2);
    border-radius: 3px;
    color: var(--primary);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 1px;
    margin-right: 8px;
    min-width: 60px;
    text-align: center;
}

.wave-announce {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 50;
    text-align: center;
    pointer-events: none;
}

.wave-text {
    font-size: 48px;
    font-weight: 900;
    letter-spacing: 8px;
    color: var(--primary);
    text-shadow: 0 0 40px rgba(0, 180, 255, 0.6);
    animation: waveIn 2s ease-out forwards;
}

.boss-announce {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 50;
    text-align: center;
    pointer-events: none;
}

.boss-warn {
    font-size: 20px;
    letter-spacing: 8px;
    color: var(--danger);
    animation: bossFlash 0.5s ease infinite alternate;
}

.boss-announce-name {
    font-size: 36px;
    font-weight: 900;
    letter-spacing: 4px;
    color: var(--danger);
    text-shadow: 0 0 30px rgba(255, 50, 80, 0.6);
    animation: waveIn 2.5s ease-out forwards;
}

@keyframes waveIn {
    0% { opacity: 0; transform: scale(0.5); }
    20% { opacity: 1; transform: scale(1.1); }
    80% { opacity: 1; transform: scale(1); }
    100% { opacity: 0; transform: scale(1); }
}

@keyframes bossFlash {
    0% { opacity: 0.6; }
    100% { opacity: 1; }
}