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

body {
    background: #020410;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
    overflow: hidden;
}

#game-container {
    position: relative;
    width: 480px;
    height: 720px;
    border: 1px solid rgba(0, 100, 200, 0.3);
    border-radius: 4px;
    overflow: hidden;
    box-shadow:
        0 0 30px rgba(0, 100, 200, 0.2),
        0 0 60px rgba(0, 60, 150, 0.1),
        inset 0 0 30px rgba(0, 50, 120, 0.1);
}

#gameCanvas {
    display: block;
    width: 100%;
    height: 100%;
    background: #030518;
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: rgba(2, 4, 16, 0.88);
    backdrop-filter: blur(4px);
    z-index: 10;
    transition: opacity 0.3s ease;
}

.overlay.hidden {
    display: none;
}

.game-title {
    font-size: 40px;
    font-weight: 900;
    color: #00d4ff;
    text-shadow:
        0 0 10px rgba(0, 212, 255, 0.8),
        0 0 30px rgba(0, 180, 255, 0.4),
        0 0 60px rgba(0, 140, 255, 0.2);
    margin-bottom: 6px;
    letter-spacing: 10px;
    animation: titleGlow 3s ease-in-out infinite;
}

@keyframes titleGlow {
    0%, 100% { text-shadow: 0 0 10px rgba(0, 212, 255, 0.8), 0 0 30px rgba(0, 180, 255, 0.4), 0 0 60px rgba(0, 140, 255, 0.2); }
    50% { text-shadow: 0 0 15px rgba(0, 212, 255, 1), 0 0 40px rgba(0, 180, 255, 0.6), 0 0 80px rgba(0, 140, 255, 0.3); }
}

.subtitle {
    color: rgba(100, 140, 180, 0.6);
    font-size: 13px;
    margin-bottom: 50px;
    letter-spacing: 6px;
    text-transform: uppercase;
}

.overlay h1 {
    color: #00d4ff;
    font-size: 32px;
    font-weight: 800;
    text-shadow: 0 0 15px rgba(0, 212, 255, 0.5);
    margin-bottom: 24px;
    letter-spacing: 8px;
}

.overlay p {
    color: #8ab4d0;
    font-size: 18px;
    margin-bottom: 8px;
}

#final-score {
    font-size: 32px !important;
    color: #ffdd44 !important;
    text-shadow: 0 0 15px rgba(255, 221, 68, 0.5);
    margin-bottom: 8px !important;
    font-weight: bold;
}

#best-score {
    color: rgba(120, 160, 200, 0.7) !important;
    font-size: 15px !important;
    margin-bottom: 36px !important;
}

.btn {
    padding: 12px 44px;
    font-size: 15px;
    font-weight: bold;
    border: 1px solid rgba(0, 180, 255, 0.5);
    background: rgba(0, 100, 200, 0.1);
    color: #00d4ff;
    border-radius: 4px;
    cursor: pointer;
    margin-top: 14px;
    letter-spacing: 4px;
    transition: all 0.25s ease;
    font-family: inherit;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(0, 200, 255, 0.1), transparent);
    transition: left 0.4s ease;
}

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

.btn:hover {
    background: rgba(0, 180, 255, 0.2);
    border-color: rgba(0, 200, 255, 0.8);
    box-shadow: 0 0 20px rgba(0, 180, 255, 0.3);
    text-shadow: 0 0 8px rgba(0, 212, 255, 0.6);
}

.btn:active {
    transform: scale(0.97);
}

.btn-secondary {
    border-color: rgba(80, 120, 160, 0.4);
    color: rgba(100, 150, 190, 0.8);
    font-size: 13px;
    padding: 9px 32px;
    background: rgba(40, 60, 100, 0.08);
}

.btn-secondary:hover {
    background: rgba(80, 120, 160, 0.15);
    border-color: rgba(100, 150, 190, 0.6);
    color: #8ab4d0;
    box-shadow: 0 0 15px rgba(80, 120, 160, 0.2);
}

.controls-info {
    margin-top: 50px;
    text-align: center;
}

.controls-info p {
    color: rgba(70, 100, 130, 0.7);
    font-size: 12px;
    margin-bottom: 6px;
    letter-spacing: 1px;
}