/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 返回主页按钮 */
.home-btn {
    position: fixed;
    top: 20px;
    left: 20px;
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    text-decoration: none;
    transition: all 0.3s ease;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.home-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.1);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    color: #fff;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
}

/* 头部样式 */
header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    background: linear-gradient(90deg, #ff6b6b, #feca57, #48dbfb, #ff9ff3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    color: #a0a0a0;
    font-size: 1.1rem;
}

/* 主内容区域 */
.main-content {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 30px;
}

/* 视频区域 */
.video-section {
    flex: 1;
    min-width: 300px;
    max-width: 640px;
}

.video-container {
    position: relative;
    background: #000;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
}

#video {
    width: 100%;
    display: block;
    transform: scaleX(-1);
}

#overlay-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transform: scaleX(-1);
    pointer-events: none;
}

.video-status {
    position: absolute;
    top: 10px;
    left: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(0, 0, 0, 0.7);
    padding: 8px 15px;
    border-radius: 20px;
    font-size: 0.85rem;
}

.status-indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #f39c12;
    animation: pulse 1.5s infinite;
}

.status-indicator.active {
    background: #2ecc71;
}

.status-indicator.error {
    background: #e74c3c;
    animation: none;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* 绘画画布区域 */
.canvas-section {
    flex: 1;
    min-width: 300px;
    max-width: 640px;
    position: relative;
}

#draw-canvas {
    width: 100%;
    height: 480px;
    background: #fff;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    cursor: crosshair;
}

#hand-overlay-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 480px;
    border-radius: 15px;
    pointer-events: none;
}

/* 控制面板 */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
    align-items: center;
    background: rgba(255, 255, 255, 0.1);
    padding: 20px;
    border-radius: 15px;
    backdrop-filter: blur(10px);
    margin-bottom: 30px;
}

.control-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.control-group label {
    font-size: 0.9rem;
    color: #ccc;
}

/* 颜色选择器 */
#color-picker {
    width: 60px;
    height: 40px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    background: none;
}

#color-picker::-webkit-color-swatch-wrapper {
    padding: 0;
}

#color-picker::-webkit-color-swatch {
    border: 2px solid #fff;
    border-radius: 8px;
}

/* 滑块样式 */
#brush-size {
    width: 150px;
    height: 8px;
    -webkit-appearance: none;
    appearance: none;
    background: linear-gradient(90deg, #667eea, #764ba2);
    border-radius: 4px;
    outline: none;
}

#brush-size::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    background: #fff;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.3);
}

#brush-size::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: #fff;
    border-radius: 50%;
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.3);
}

/* 按钮样式 */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
}

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

.btn-danger {
    background: linear-gradient(135deg, #e74c3c, #c0392b);
    color: #fff;
}

.btn-secondary {
    background: linear-gradient(135deg, #95a5a6, #7f8c8d);
    color: #fff;
}

.btn-secondary.active {
    background: linear-gradient(135deg, #3498db, #2980b9);
}

.btn-success {
    background: linear-gradient(135deg, #2ecc71, #27ae60);
    color: #fff;
}

/* 使用说明 */
.instructions {
    background: rgba(255, 255, 255, 0.1);
    padding: 20px 30px;
    border-radius: 15px;
    backdrop-filter: blur(10px);
}

.instructions h3 {
    margin-bottom: 15px;
    color: #feca57;
}

.instructions ul {
    list-style: none;
}

.instructions li {
    padding: 8px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    color: #ddd;
}

.instructions li:last-child {
    border-bottom: none;
}

.instructions strong {
    color: #48dbfb;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }

    .main-content {
        flex-direction: column;
    }

    .video-section,
    .canvas-section {
        max-width: 100%;
    }

    #draw-canvas,
    #hand-overlay-canvas {
        height: 350px;
    }

    .controls {
        flex-direction: column;
    }

    .control-group {
        width: 100%;
    }

    #brush-size {
        width: 100%;
    }

    .btn {
        width: 100%;
    }
}

/* 加载动画 */
.loading {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #333;
    border-top-color: #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* 隐藏类 */
.hidden {
    display: none !important;
}