:root{color-scheme:light;--ink:#18344a;--muted:#5a6c78;--blue:#176f8a;--line:#d5e1e6;--soft:#f2f7f8;--paper:#fff;--red:#b65c36}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.65 "Microsoft YaHei","PingFang SC",sans-serif}main{max-width:1080px;margin:auto;padding:28px 30px 22px}.eyebrow{font-size:12px;color:var(--blue);letter-spacing:.08em;margin:0 0 7px}h1{font:600 clamp(25px,3.8vw,36px)/1.3 "Noto Sans CJK SC","Microsoft YaHei",sans-serif;margin:0 0 12px}.intro{max-width:890px;color:var(--muted);margin:0 0 23px}.controls{display:grid;grid-template-columns:1.25fr 1.3fr 1fr;gap:22px;padding:17px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}label{display:block;font-size:13px;font-weight:600;color:var(--muted)}select{display:block;width:100%;padding:8px 10px;margin-top:5px;border:1px solid #a7beca;border-radius:5px;color:var(--ink);background:#fff;font-family:inherit;font-size:15px}input[type=range]{width:100%;display:block;margin:15px 0 5px;accent-color:var(--blue)}output{float:right;color:var(--ink);font:600 22px/1.1 Consolas,monospace}.toolbar{display:flex;align-items:center;gap:9px;flex-wrap:wrap;padding:15px 0 13px}button{font-family:inherit;font-size:14px;line-height:1.4;padding:8px 17px;background:white;color:var(--ink);border:1px solid #a7beca;border-radius:5px;cursor:pointer}.primary{background:var(--blue);border-color:var(--blue);color:white;min-width:77px}button:disabled{opacity:.45;cursor:default}button:hover:not(:disabled){filter:brightness(.94)}a{color:var(--blue);text-underline-offset:3px}:focus-visible{outline:3px solid #e1aa57;outline-offset:3px}#timeReadout{margin-left:auto;font:16px Consolas,monospace}.grid-label{color:var(--muted);font-size:12px;padding-left:12px}.viewport{position:relative;overflow:hidden;background:#f3f7fa;border:1px solid #b7cbd5}#field{display:block;width:100%;height:auto;aspect-ratio:5/2;cursor:crosshair;image-rendering:auto}.flow-label,.axis-label{position:absolute;pointer-events:none;background:#ffffffd6;padding:2px 7px;font-size:11px;color:#345167}.flow-label{left:9px;top:9px}.axis-label{right:9px;bottom:6px}.legend-row{display:flex;align-items:center;justify-content:center;gap:10px;font:12px Consolas,"Microsoft YaHei",sans-serif;margin:10px 0 4px}.legend-bar{height:9px;width:200px;max-width:35%;background:linear-gradient(90deg,#245d9f,#f8fafb,#b65c36);border:1px solid #d0dbe2}.legend-bar.speed{background:linear-gradient(90deg,#f6fafb,#68b8cd,#173c78)}.field-note{font-size:12px;color:var(--muted);margin:5px 0 13px}#status{color:#8a3f20}.probe{border-top:1px solid var(--line);padding-top:10px}.probe-heading{display:flex;justify-content:space-between;gap:12px;align-items:baseline}h2{font-size:15px;margin:0 0 6px}.probe-heading p{font:12px Consolas,"Microsoft YaHei",monospace;color:var(--muted);margin:0}#history{width:100%;height:auto;display:block}.caption{font-size:11px;color:var(--muted);margin:0 0 15px}.parameters{display:flex;gap:12px 22px;flex-wrap:wrap;font-size:12px;padding:12px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);color:var(--muted)}.parameters b{color:var(--ink);font-weight:500}.task{font-size:14px;margin:17px 0}details{font-size:13px;color:var(--muted);padding:5px 0}summary{cursor:pointer;color:var(--ink);font-weight:600}details p{margin:10px 0}footer{border-top:1px solid var(--line);margin-top:18px;padding-top:11px;display:flex;justify-content:space-between;gap:10px;font-size:11px;color:var(--muted)}body.embed main{padding:16px 20px 14px;max-width:none}body.embed footer #backToBook{display:none}@media(max-width:650px){main{padding:20px 16px}.controls{grid-template-columns:1fr 1fr;gap:12px}.re-control{grid-column:1/-1;grid-row:2}.toolbar{gap:7px}button{padding:7px 12px}.grid-label{display:none}#timeReadout{font-size:13px}.probe-heading{display:block}.probe-heading p{margin-bottom:5px}.parameters{gap:6px 14px}.legend-row{font-size:10px;gap:5px}footer{display:block}.axis-label,.flow-label{font-size:9px;padding:1px 4px}body.embed main{padding:14px 12px}}