.input-group-custom {
            margin-bottom: 1rem;
        }.form-label{font-size:0.9rem}
        .deep-dive {
            margin: 1.8rem 0;
        }
        .deep-dive p {
            text-align: justify;
        }
        .unit-note {
            font-size: 0.9rem;
            color: #6c757d;
        }
        .coord-input {
            margin-bottom: 0.5rem;
        }
        .rebar-chart-container {
            background-color: #f9fafc;
            border-radius: 8px;
            padding: 1.5rem;
            border: 1px solid #e9ecef;
            margin-top: 1.5rem;
        }
        .rebar-chart {
            width: 100%;
            height: auto;
            background-color: #ffffff;
            border-radius: 6px;
        }
        .bar-size-badge {
            display: inline-block;
            padding: 0.25rem 0.6rem;
            background-color: rgba(70, 130, 180, 0.12);
            border-radius: 12px;
            font-size: 0.8rem;
            font-weight: 500;
            color: var(--accent-color);
            margin: 0.1rem 0.2rem;
        }
        .density-note {
            font-size: 0.9rem;
            color: #495057;
            background-color: #f1f3f5;
            padding: 0.5rem 0.75rem;
            border-radius: 4px;
        }
        .steel-grade-tag {
            display: inline-block;
            padding: 0.2rem 0.8rem;
            background-color: #2c3e50;
            color: #fff;
            border-radius: 16px;
            font-size: 0.75rem;
            font-weight: 600;
            letter-spacing: 0.3px;
        }
        .rebar-visual {
            display: flex;
            align-items: center;
            gap: 1rem;
            flex-wrap: wrap;
            margin: 0.5rem 0;
        }
        .rebar-visual .bar {
            height: 20px;
            background: linear-gradient(180deg, #8b8b8b, #c0c0c0);
            border-radius: 4px;
            border: 1px solid #6c757d;
            flex-shrink: 0;
        }
        .rebar-visual .label {
            font-size: 0.85rem;
            color: #495057;
        }
        .formula-card {
            background-color: #f8f9fa;
            border: 1px solid #e9ecef;
            border-radius: 6px;
            padding: 1.2rem;
            margin: 0.8rem 0;
        }
        .formula-card code {
            background-color: #e9ecef;
            padding: 0.2rem 0.5rem;
            border-radius: 3px;
            font-size: 0.95rem;
        }
        .input-group-text-custom {
            background-color: #f1f3f5;
            border: 1px solid #dee2e6;
        }
        .calc-section {
            background-color: #ffffff;
            border-radius: 8px;
            padding: 1.2rem;
            box-shadow: 0 1px 3px rgba(0,0,0,0.04);
            border: 1px solid #e9ecef;
        }
        .calc-section .weight-tonnes {
            font-size: 1rem;
            color: #6c757d;
            margin-left: 0.5rem;
        }
        @media (max-width: 768px) {
            }