:root {
            --primary-blue: #0056b3;
            --secondary-blue: #e0f7fa;
            --accent-red: #d9534f;
            --text-dark: #333;
            --bg-light: #f8f9fa;
            --border-color: #ddd;
        }

        body {
            font-family: 'Verdana', sans-serif;
            line-height: 1.7;
            color: var(--text-dark);
            margin: 0;
            padding: 0;
            background-color: #f4f7f9;
        }

        .container {
            max-width: 1000px;
            margin: 40px auto;
            padding: 40px;
            background-color: #fff;
            box-shadow: 0 4px 20px rgba(0,0,0,0.08);
            border-radius: 8px;
        }

        /* Heading Hierarchy Optimization */
        h2 { 
            color: var(--primary-blue); 
            font-size: 30px; 
            margin-bottom: 20px; 
            border-bottom: 4px solid var(--primary-blue);
            padding-bottom: 15px;
            text-align: center;
        }

        h3 { 
            color: var(--primary-blue); 
            font-size: 20px; 
            border-left: 6px solid var(--primary-blue); 
            padding-left: 15px; 
            margin-top: 40px; 
            margin-bottom: 20px;
            background: linear-gradient(90deg, #f0f7ff 0%, #ffffff 100%);
            padding-top: 8px;
            padding-bottom: 8px;
        }

        p { margin-bottom: 1.5em; }

        /* Images */
        .content-image {
            width: 100%;
            height: auto;
            border-radius: 8px;
            margin: 30px 0;
            display: block;
            border: 1px solid var(--border-color);
        }

        /* JIS Badge & Highlights */
        .jis-section {
            background-color: var(--bg-light);
            border: 1px solid var(--border-color);
            padding: 25px;
            border-radius: 8px;
            margin: 25px 0;
        }

        .badge {
            display: inline-block;
            background-color: var(--primary-blue);
            color: #fff;
            padding: 2px 12px;
            border-radius: 4px;
            font-size: 12px;
            font-weight: bold;
            margin-bottom: 10px;
            text-transform: uppercase;
        }

        /* Standards Table */
        .standards-table-wrapper {
            overflow-x: auto;
            margin: 20px 0;
        }

        .standards-table {
            width: 100%;
            border-collapse: collapse;
            background: #fff;
        }

        .standards-table th, .standards-table td {
            border: 1px solid var(--border-color);
            padding: 15px;
            text-align: center;
        }

        .standards-table th {
            background-color: var(--primary-blue);
            color: white;
            font-size: 14px;
        }

        /* Calculator Styles */
        .calc-wrapper {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 30px;
            margin: 40px 0;
        }

        .calc-card {
            background: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 30px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.05);
            transition: all 0.3s ease;
        }

        .calc-card:hover { 
            transform: translateY(-5px); 
            box-shadow: 0 8px 24px rgba(0,0,0,0.1);
        }

        .calc-card h4 { 
            margin-top: 0; 
            color: var(--primary-blue); 
            font-size: 18px;
            border-bottom: 1px solid var(--secondary-blue);
            padding-bottom: 10px;
        }

        .input-group { margin-bottom: 20px; }
        .input-group label { display: block; font-weight: bold; margin-bottom: 8px; font-size: 14px; color: #555; }
        
        .input-wrapper { display: flex; align-items: center; }
        .input-wrapper input {
            flex: 1;
            padding: 12px;
            border: 1px solid #ccc;
            border-radius: 4px;
            font-size: 16px;
        }

        .unit { width: 60px; margin-left: 10px; color: #777; font-size: 13px; font-weight: bold; }

        .result-box {
            margin-top: 20px;
            padding: 20px;
            background-color: var(--secondary-blue);
            border: 1px solid #b2ebf2;
            border-radius: 8px;
            text-align: center;
        }

        .result-label { font-size: 11px; color: #007c91; display: block; text-transform: uppercase; letter-spacing: 1px; font-weight: bold; }
        .result-value { font-size: 26px; font-weight: bold; color: var(--primary-blue); margin-top: 5px; }

        /* Formula Display */
        .formula-display {
            background: #2c3e50;
            color: #ecf0f1;
            padding: 25px;
            border-radius: 8px;
            text-align: center;
            font-family: 'Courier New', monospace;
            margin: 25px 0;
            font-size: 1.2em;
            box-shadow: inset 0 2px 10px rgba(0,0,0,0.2);
        }

        .safety-alert {
            color: #fff;
            background-color: var(--accent-red);
            font-weight: bold;
            padding: 20px;
            border-radius: 8px;
            margin: 40px 0;
            display: flex;
            align-items: center;
        }

        .safety-alert::before {
            content: "⚠️";
            font-size: 30px;
            margin-right: 20px;
        }

        /* Responsive */
        @media (max-width: 768px) {
            .container { padding: 20px; margin: 10px; }
            .calc-wrapper { grid-template-columns: 1fr; }
            h2 { font-size: 24px; }
        }