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

body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: white;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2.5em;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.controls {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

button {
    padding: 12px 24px;
    border: none;
    border-radius: 25px;
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    color: white;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.3);
}

button:active {
    transform: translateY(0);
}

select, input[type="range"] {
    padding: 10px;
    border: none;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.9);
    font-size: 14px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

#sizeValue {
    font-weight: bold;
    background: rgba(255, 255, 255, 0.2);
    padding: 5px 15px;
    border-radius: 15px;
}

.canvas-container {
    position: relative;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

#video {
    width: 100%;
    height: auto;
    border-radius: 20px;
    transform: scaleX(-1); /* 镜像翻转 */
}

#drawingCanvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    cursor: none;
    border-radius: 20px;
}

.instructions {
    background: rgba(255, 255, 255, 0.1);
    padding: 20px;
    border-radius: 15px;
    margin: 20px auto;
    max-width: 800px;
    backdrop-filter: blur(10px);
}

.instructions h3 {
    margin-bottom: 15px;
    text-align: center;
    color: #ffd700;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.5);
}

.instructions ul {
    list-style: none;
    padding: 0;
}

.instructions li {
    margin: 10px 0;
    padding: 8px 12px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    border-left: 4px solid #ffd700;
}

.status {
    text-align: center;
    margin-top: 20px;
}

#statusText {
    font-size: 18px;
    background: rgba(255, 255, 255, 0.1);
    padding: 15px;
    border-radius: 15px;
    display: inline-block;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .controls {
        flex-direction: column;
        gap: 10px;
    }
    
    h1 {
        font-size: 2em;
    }
    
    button {
        width: 100%;
        max-width: 200px;
    }
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 1s ease-in-out infinite;
}

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