.result-highlight {
            background: linear-gradient(135deg, #f8f9fc 0%, #eef2f7 100%);
            border-radius: 20px;
            padding: 1.6rem;
            margin-top: 1.5rem;
            border: 1px solid rgba(70, 130, 180, 0.2);
        }
        .hr-value {
            font-size: 2.8rem;
            font-weight: 800;
            color: var(--primary-color);
            line-height: 1.2;
        }
        .zone-badge {
            background-color: #f0f4f9;
            padding: 0.3rem 0.8rem;
            border-radius: 30px;
            font-size: 0.8rem;
            font-weight: 600;
            display: inline-block;
            margin-bottom: 0.5rem;
        }
        .progress-bar-custom {
            height: 12px;
            border-radius: 20px;
            background-color: #e9ecef;
            overflow: hidden;
            margin: 0.5rem 0;
        }
        .progress-fill {
            height: 100%;
            width: 0%;
            background: #2c7da0;
            border-radius: 20px;
            transition: width 0.2s ease;
        }
        .intensity-slider {
            width: 100%;
            margin-top: 0.5rem;
        }
        .zone-table td {
            vertical-align: middle;
        }
        .formula-card {
            background: white;
            border-radius: 16px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.03);
            border: 1px solid #eef2f9;
            padding: 1rem;
        }
        .insight-icon {
            font-size: 1.8rem;
            color: #2c7da0;
        }
        .custom-tooltip {
            border-bottom: 1px dashed #aaa;
            cursor: help;
        }
        .hr-intense {
            color: #c44536;
            font-weight: 700;
        }
        .euler-note {
            background-color: #eef2fa;
            border-left: 4px solid #2c7da0;
        }
        .legend-color.zone1 { background-color: #2c7da0; }
        .legend-color.zone2 { background-color: #3c96bc; }
        .legend-color.zone3 { background-color: #61a5c2; }
        .legend-color.zone4 { background-color: #e9c46a; }
        .legend-color.zone5 { background-color: #e76f51; }