:root {
            --primary-color: #3b82f6;
            --primary-hover: #2563eb;
            --bg-color: #f1f5f9;
            --card-bg: #ffffff;
            --text-main: #1e293b;
            --text-muted: #64748b;
            --panel-bg: #f8f9fa;
            --border-color: #e2e8f0;
        }

        body {
            font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
            background-color: var(--bg-color);
            color: var(--text-main);
            margin: 0;
            justify-content: center;
            align-items: flex-start;
            min-height: 100vh;
        }

        .container { margin: 20px; }

        .card {
            background: var(--card-bg);
            border-radius: 20px;
            box-shadow: 0 10px 25px rgba(0,0,0,0.05);
            padding: 40px;
            border: 1px solid var(--border-color);
            position: relative;
        }

        h1 {
            text-align: center;
            font-size: 2rem;
            color: var(--text-main);
            margin-bottom: 10px;
            font-weight: 800;
        }

        .description {
            margin-bottom: 30px;
            color: var(--text-muted);
            font-size: 1.05rem;
            text-align: center;
            max-width: 700px;
            margin-left: auto;
            margin-right: auto;
        }

        .sim-wrapper {
            display: flex !important;
            justify-content: center !important;
            align-items: flex-start !important;
            width: 100% !important;
            margin: 20px 0 !important;
            overflow: visible !important;
        }

        #total {
            width: 700px;
            height: 400px;
            position: relative;
            background: white;
            border: 1px solid var(--border-color);
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 4px 12px rgba(0,0,0,0.05);
            transform-origin: top center;
            flex-shrink: 0;
        }

        #canvas {
            position: absolute;
            left: 0;
            top: 0;
            width: 400px;
            height: 400px;
        }

        #panel {
            position: absolute;
            left: 400px;
            top: 0;
            width: 300px;
            height: 400px;
            background: var(--panel-bg);
            border-left: 1px solid var(--border-color);
            padding: 20px;
            box-sizing: border-box;
            display: flex !important;
            flex-direction: column !important;
            gap: 15px !important;
        }

        /* 覆盖 app.css 中的强制绝对定位 */
        #panel div, #panel span, #panel input, #panel select, #panel button, #panel label {
            position: static !important;
        }

        #panel span {
            white-space: normal !important;
        }

        .input-group {
            display: flex !important;
            flex-direction: column !important;
            gap: 8px !important;
        }

        .input-row {
            display: flex !important;
            align-items: center !important;
            justify-content: space-between !important;
            gap: 10px !important;
        }

        label {
            font-size: 0.85rem;
            font-weight: 600;
            color: var(--text-main);
            white-space: nowrap;
        }

        input[type="text"] {
            width: 100px;
            padding: 8px 12px;
            border: 1px solid var(--border-color);
            border-radius: 6px;
            font-size: 0.95rem;
            outline: none;
            transition: all 0.2s;
            text-align: center;
            background: #fff;
        }

        input[type="text"]:focus {
            border-color: var(--primary-color);
            box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
        }

        .btn-primary {
            background: var(--primary-color);
            color: white;
            border: none;
            padding: 12px;
            border-radius: 8px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
            margin-top: 5px;
            text-align: center;
        }

        .btn-primary:hover {
            background: var(--primary-hover);
            transform: translateY(-1px);
        }

        .status-msg {
            font-size: 0.85rem;
            color: var(--text-muted);
            padding: 10px;
            background: #fff;
            border-radius: 6px;
            border: 1px solid var(--border-color);
            min-height: 40px;
            display: flex !important;
            align-items: center !important;
        }

        .footer-info {
            text-align: center;
            margin-top: 40px;
            font-size: 0.85rem;
            color: #94a3b8;
        }

        /* Mobile full-width adaptation */
        @media (max-width: 600px) {
            .container { margin: 0 !important; padding: 0 !important; }
            .card { padding: 15px 10px !important; border-radius: 0 !important; }
            .sim-wrapper { margin: 10px 0 !important; }
        }