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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    overflow: hidden;
    background: #000;
    position: relative;
}

/* 视频层：镜像翻转 */
#video {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    object-fit: cover;
    transform: scaleX(-1);
    z-index: 1;
}

/* Canvas层：绘制在视频之上 */
#canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 2;
    pointer-events: none;
}

/* UI层 */
.ui-layer {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 3;
    pointer-events: none;
}

/* 引导文字 */
.guide-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: #fff;
    animation: pulse 2s ease-in-out infinite;
}

.guide-text .gesture-icon {
    font-size: 120px;
    margin-bottom: 20px;
    opacity: 0.8;
}

.guide-text .text {
    font-size: 24px;
    font-weight: 600;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.5);
}

/* 成功提示 */
.success-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: #fff;
    animation: fadeIn 0.5s ease-out;
}

.success-text .text {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 30px;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.5);
}

.btn-next {
    pointer-events: auto;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    border: none;
    padding: 16px 48px;
    font-size: 20px;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
    transition: all 0.3s ease;
}

.btn-next:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}

.btn-next:active {
    transform: translateY(0);
}

/* 加载动画 */
.loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: #fff;
}

.loading .spinner {
    width: 50px;
    height: 50px;
    margin: 0 auto 20px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.loading .text {
    font-size: 16px;
    font-weight: 500;
}

/* 动画 */
@keyframes pulse {
    0%, 100% {
        transform: translate(-50%, -50%) scale(1);
    }
    50% {
        transform: translate(-50%, -50%) scale(1.05);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* 适配不同屏幕 */
@media (max-width: 375px) {
    .guide-text .gesture-icon {
        font-size: 100px;
    }

    .guide-text .text {
        font-size: 20px;
    }

    .success-text .text {
        font-size: 28px;
    }

    .btn-next {
        padding: 14px 40px;
        font-size: 18px;
    }
}