body{font-family:Helvetica Neue,Arial,sans-serif;font-size:15px;color:#333;max-width:960px;margin:0 auto;padding:20px 24px;background:#fff}h3{font-size:22px;font-weight:600;margin-bottom:6px}p em{font-size:14px;color:#555}.section-header{background:#2c3e50;color:#fff;padding:6px 12px;font-weight:600;font-size:14px;margin:20px 0 8px}.section-body{padding:10px 12px;background:#f9f9f9;border:1px solid #e0e0e0;border-top:none}.input-row{display:flex;align-items:center;margin:6px 0;gap:10px}input[type=text]{width:130px;padding:4px 8px;border:1px solid #bbb;border-radius:3px;font-size:14px;text-align:right}input[type=text]:read-only{background:#f0f0f0;color:#444}button.calc-button{background:#2c3e50;color:#fff;border:none;padding:10px 24px;font-size:14px;font-weight:600;letter-spacing:.5px;cursor:pointer;border-radius:3px;margin:16px 0}button.calc-button:hover{background:#3d5166}.error{color:#c00;font-weight:500;margin:2px 0;min-height:18px}.warning{color:#e07000;font-weight:500;margin:2px 0;min-height:18px}.ok{color:#070;font-weight:500;margin:2px 0;min-height:18px}.plot-container{width:100%;height:500px;margin:16px 0}