/* ==================== UI 屏幕 ==================== */

/* 开始屏幕 */
.start-screen {
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 1;
    transition: opacity 0.3s;
}

.start-screen.hidden {
    display: none;
    opacity: 0;
}

.start-content {
    background: rgba(10, 14, 39, 0.98);
    border: 2px solid var(--color-primary);
    border-radius: 10px;
    padding: 60px 50px;
    text-align: center;
    box-shadow: var(--shadow-glow-strong), inset 0 0 40px rgba(0, 212, 255, 0.1);
    backdrop-filter: blur(10px);
    max-width: 500px;
    animation: slideInUp 0.5s ease-out;
}

.start-content h1 {
    font-size: 48px;
    margin-bottom: 10px;
    text-shadow: var(--shadow-glow);
    letter-spacing: 3px;
    text-transform: uppercase;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 16px;
    color: var(--color-text-muted);
    margin-bottom: 30px;
    letter-spacing: 1px;
}

.start-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 30px;
    padding: 20px;
    background: rgba(0, 212, 255, 0.05);
    border-radius: 8px;
    border: 1px solid rgba(0, 212, 255, 0.2);
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.stat-item .label {
    font-size: 12px;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-item .value {
    font-size: 24px;
    color: var(--color-primary);
    font-weight: bold;
}

.start-button {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: var(--color-bg);
    border: none;
    padding: 16px 50px;
    font-size: 16px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 2px;
    transition: var(--transition-smooth);
    margin-bottom: 30px;
    pointer-events: auto;
}

.start-button:hover {
    box-shadow: var(--shadow-glow-strong);
    transform: scale(1.05);
}

.controls-info {
    display: flex;
    flex-direction: column;
    gap: 8px;
    font-size: 13px;
    color: var(--color-text-muted);
}

.controls-info p {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.key {
    background: rgba(0, 212, 255, 0.1);
    border: 1px solid var(--color-primary);
    padding: 4px 8px;
    border-radius: 3px;
    color: var(--color-primary);
    font-weight: bold;
    font-size: 12px;
}

/* 游戏结束屏幕 */
.game-over-screen {
    display: none;
    opacity: 0;
    transition: opacity 0.3s;
}

.game-over-screen.show {
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 1;
}

.game-over-content {
    background: rgba(10, 14, 39, 0.98);
    border: 2px solid var(--color-primary);
    border-radius: 10px;
    padding: 50px 40px;
    text-align: center;
    box-shadow: var(--shadow-glow-strong), inset 0 0 40px rgba(0, 212, 255, 0.1);
    backdrop-filter: blur(10px);
    max-width: 600px;
    animation: slideInUp 0.5s ease-out;
    pointer-events: auto;
}

.game-over-content h1 {
    font-size: 48px;
    margin-bottom: 20px;
    text-shadow: var(--shadow-glow);
    letter-spacing: 3px;
    text-transform: uppercase;
    color: var(--color-primary);
}

.final-score {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 30px;
    padding: 20px;
    background: linear-gradient(135deg, rgba(0, 212, 255, 0.1), rgba(118, 75, 162, 0.1));
    border-radius: 8px;
    border: 1px solid var(--color-primary);
}

.final-score .label {
    font-size: 12px;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.final-score .value {
    font-size: 48px;
    color: var(--color-primary);
    font-weight: bold;
    text-shadow: var(--shadow-glow);
}

.stats-breakdown {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 30px;
}

.stat-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px;
    background: rgba(0, 212, 255, 0.05);
    border-left: 2px solid var(--color-primary);
    border-radius: 4px;
}

.stat-row .label {
    font-size: 12px;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-row .value {
    font-size: 18px;
    color: var(--color-primary);
    font-weight: bold;
}

.achievement-section {
    margin-bottom: 30px;
    padding: 20px;
    background: linear-gradient(135deg, rgba(0, 255, 136, 0.1), rgba(0, 212, 255, 0.1));
    border: 2px solid var(--color-success);
    border-radius: 8px;
}

.achievement-section h3 {
    color: var(--color-success);
    margin-bottom: 10px;
    font-size: 16px;
    text-shadow: 0 0 10px rgba(0, 255, 136, 0.6);
}

.achievement-section p {
    color: var(--color-text-muted);
    font-size: 13px;
}

.button-group {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-bottom: 30px;
}

.btn-primary, .btn-secondary {
    border: none;
    padding: 14px 35px;
    font-size: 14px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: var(--transition-smooth);
    pointer-events: auto;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: var(--color-bg);
}

.btn-primary:hover {
    box-shadow: var(--shadow-glow-strong);
    transform: scale(1.05);
}

.btn-secondary {
    background: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
}

.btn-secondary:hover {
    background: rgba(0, 212, 255, 0.1);
    box-shadow: var(--shadow-glow);
}

.leaderboard-preview {
    padding: 20px;
    background: rgba(0, 212, 255, 0.05);
    border: 1px solid var(--color-primary);
    border-radius: 8px;
    text-align: left;
}

.leaderboard-preview h3 {
    font-size: 14px;
    color: var(--color-primary);
    margin-bottom: 15px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

#topScoresList {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.score-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px;
    background: rgba(0, 212, 255, 0.05);
    border-radius: 4px;
    font-size: 13px;
}

.score-rank {
    color: var(--color-primary);
    font-weight: bold;
    min-width: 30px;
}

.score-value {
    color: var(--color-text-muted);
}

/* 暂停屏幕 */
.pause-screen {
    display: none;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s;
}

.pause-screen.show {
    display: flex;
    opacity: 1;
}

.pause-content {
    background: rgba(10, 14, 39, 0.98);
    border: 2px solid var(--color-primary);
    border-radius: 10px;
    padding: 50px 40px;
    text-align: center;
    box-shadow: var(--shadow-glow-strong);
    backdrop-filter: blur(10px);
    pointer-events: auto;
}

.pause-content h1 {
    font-size: 48px;
    margin-bottom: 30px;
    color: var(--color-primary);
    text-shadow: var(--shadow-glow);
    letter-spacing: 3px;
    text-transform: uppercase;
}

.pause-content .button-group {
    flex-direction: column;
}

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
    .start-content,
    .game-over-content,
    .pause-content {
        padding: 30px 20px;
        max-width: 90vw;
    }

    .start-content h1,
    .game-over-content h1,
    .pause-content h1 {
        font-size: 32px;
    }

    .final-score .value {
        font-size: 36px;
    }

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

    .button-group {
        flex-direction: column;
    }

    .btn-primary, .btn-secondary {
        width: 100%;
    }
}