:root {
            --primary-color: #e63946; /* 经典红 */
            --secondary-color: #ff6b6b; /* 浅红用于渐变 */
            
            /* 毛玻璃参数 */
            --glass-bg: rgba(255, 255, 255, 0.25);
            --glass-border: 1px solid rgba(255, 255, 255, 0.4);
            --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.15);
            --glass-blur: blur(20px);
        }

        body {
            font-family: 'Noto Sans SC', 'Segoe UI', sans-serif;
            /* 红色系背景图，为了配合白色的Footer文字，选稍微深一点的背景 */
            background-image: url('../images/yzBJ.png');
            background-size: cover;
            background-position: center;
            background-attachment: fixed;
            background-repeat: no-repeat;
            
            color: #2d3436;
            margin: 0;
            padding: 20px;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            /* 让内容稍微靠上，给Footer留位置 */
            justify-content: flex-start; 
            padding-top: 5vh; 
            position: relative;
        }

        /* 添加暗色覆盖层 */
        body::before {
            content: '';
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.4); /* 半透明黑色覆盖层 */
            z-index: -1;
        }

        .container {
            max-width: 1000px;
            width: 100%;
            padding: 35px;
            border-radius: 24px;
            
            /* 毛玻璃效果 */
            background: var(--glass-bg);
            backdrop-filter: var(--glass-blur);
            -webkit-backdrop-filter: var(--glass-blur);
            border: var(--glass-border);
            box-shadow: var(--glass-shadow);
            margin-bottom: 20px; /* 与 Footer 的间距 */
        }

        h1 {
            color: #c0392b; /* 深红色标题 */
            text-align: center;
            margin-bottom: 10px;
            text-shadow: 1px 1px 2px rgba(255,255,255,0.4);
        }

        p.subtitle {
            text-align: center;
            color: #2d3436;
            margin-bottom: 35px;
            font-weight: 500;
        }

        .controls {
            display: flex;
            gap: 25px;
            margin-bottom: 30px;
            flex-wrap: wrap;
            align-items: center;
            justify-content: center;
            padding: 25px;
            border-radius: 16px;
            background: rgba(255, 255, 255, 0.4);
            backdrop-filter: blur(15px);
            border: var(--glass-border);
        }

        .control-group {
            display: flex;
            align-items: center;
            gap: 12px;
            font-weight: 600;
        }

        input[type="range"] {
            width: 150px;
            accent-color: var(--primary-color);
            cursor: pointer;
        }

        .btn {
            padding: 12px 28px;
            border: none;
            border-radius: 12px;
            cursor: pointer;
            font-size: 16px;
            font-weight: 600;
            transition: all 0.3s ease;
            box-shadow: 0 4px 10px rgba(0,0,0,0.1);
        }

        .btn-upload {
            background-color: #fff;
            color: var(--primary-color);
            border: 1px solid var(--primary-color);
        }
        .btn-upload:hover {
             background-color: var(--primary-color);
             color: white;
             transform: translateY(-2px);
        }

        .btn-download {
            background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
            color: white;
            display: none;
        }
        .btn-download:hover {
            opacity: 0.95;
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(230, 57, 70, 0.4);
        }
        
        .preview-area {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 25px;
            margin-top: 20px;
        }
        @media (max-width: 768px) {
            .preview-area {
                grid-template-columns: 1fr;
            }
        }
        .canvas-container {
            border-radius: 16px;
            min-height: 300px;
            display: flex;
            justify-content: center;
            align-items: center;
            background: linear-gradient(rgba(255,255,255,0.8), rgba(255,255,255,0.8)),
                        linear-gradient(45deg, #ccc 25%, transparent 25%),
                        linear-gradient(-45deg, #ccc 25%, transparent 25%),
                        linear-gradient(45deg, transparent 75%, #ccc 75%),
                        linear-gradient(-45deg, transparent 75%, #ccc 75%);
            background-size: 20px 20px;
            background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
            overflow: hidden;
            position: relative;
            border: var(--glass-border);
        }
        canvas {
            max-width: 100%;
            max-height: 600px;
            object-fit: contain;
            z-index: 1;
        }
        .label {
            position: absolute;
            top: 15px;
            left: 15px;
            background: rgba(230, 57, 70, 0.9); /* 红色标签 */
            backdrop-filter: blur(4px);
            color: white;
            padding: 6px 14px;
            border-radius: 8px;
            font-size: 13px;
            font-weight: 500;
            z-index: 2;
        }

        /* === ⬇️ Footer 样式 (完全参考你提供的 CSS) === 
           来源: index.css
        */
        .footer {
            text-align: center;
            padding: 20px;
            margin-top: 20px; /* 稍微调整上方间距 */
            margin-bottom: 20px;
            color: rgba(255, 255, 255, 0.9); /* 字体调亮一点以适应深色背景 */
            font-size: 0.9em;
            background: rgba(255, 255, 255, 0.15);
            border-radius: 20px;
            box-shadow:
                8px 8px 16px rgba(0, 0, 0, 0.1),
                -8px -8px 16px rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
            border: 1px solid rgba(255, 255, 255, 0.2);
            
            /* 为了让 Footer 和上面的容器宽度一致 */
            max-width: 1000px;
            width: 100%; 
        }

        .footer p {
            margin: 5px 0;
        }