:root{--ink:#173e4d;--muted:#66808a;--teal:#2f829c;--teal-dark:#216477;--teal-soft:#e9f4f5;--blue:#315fc7;--purple:#7750c9;--orange:#e98a20;--orange-soft:#fff1dd;--green:#278b68;--line:#c8dadd;--paper:#fff;--page:#f1f7f7;--shadow:0 16px 44px rgba(31,71,82,.12)}
*{box-sizing:border-box}
body{margin:0;min-width:320px;color:var(--ink);background:linear-gradient(rgba(47,130,156,.035) 1px,transparent 1px),linear-gradient(90deg,rgba(47,130,156,.035) 1px,transparent 1px),var(--page);background-size:32px 32px;font-family:"Microsoft YaHei","PingFang SC","Noto Sans SC",system-ui,sans-serif}
button,input{font:inherit}button{touch-action:manipulation}
.page-shell{width:min(1440px,calc(100% - 32px));margin:0 auto;padding:30px 0 52px}
.page-header{display:flex;align-items:flex-end;justify-content:space-between;gap:28px;margin-bottom:22px;padding:0 4px}
.eyebrow{display:block;color:var(--orange);font-size:15px;font-weight:850;letter-spacing:.12em;margin-bottom:8px}
h1{font-size:clamp(31px,3.4vw,50px);line-height:1.08;margin:0 0 10px;letter-spacing:-.035em}
.page-header p{margin:0;color:var(--muted);font-size:17px;line-height:1.6}
.experiment-nav{display:flex;gap:8px;flex-wrap:wrap;justify-content:flex-end}
.experiment-nav a,.experiment-nav span{padding:9px 13px;border-radius:999px;border:1px solid var(--line);font-size:13px;font-weight:800;text-decoration:none}
.experiment-nav a{background:#fff;color:var(--teal-dark)}.experiment-nav span{background:var(--teal);border-color:var(--teal);color:#fff}
.workspace{display:grid;grid-template-columns:340px minmax(0,1fr);gap:20px;align-items:start}
.control-panel,.experiment-panel,.quantity-panel,.relation-panel{background:var(--paper);border:1px solid rgba(152,184,190,.68);box-shadow:var(--shadow);border-radius:22px}
.control-panel{padding:21px;position:sticky;top:14px}.experiment-panel{padding:19px;min-width:0}
.section-title{display:flex;align-items:center;gap:11px}.step-number{display:grid;place-items:center;flex:0 0 auto;width:38px;height:38px;border-radius:12px;background:var(--orange-soft);color:var(--orange);font-size:14px;font-weight:900}
h2{font-size:20px;margin:0}.section-title p{margin:4px 0 0;color:var(--muted);font-size:13px}
.range-control{display:flex;align-items:flex-end;justify-content:space-between;gap:12px;margin:22px 0 10px;color:var(--muted);font-size:14px}.range-control strong{color:var(--ink);font-size:17px;white-space:nowrap}
input[type=range]{width:100%;height:8px;appearance:none;background:linear-gradient(90deg,var(--teal) 0 50%,#dbe7e9 50%);border-radius:999px;outline:none}
input[type=range]::-webkit-slider-thumb{appearance:none;width:23px;height:23px;border-radius:50%;background:#fff;border:7px solid var(--teal);box-shadow:0 3px 10px rgba(23,62,77,.2);cursor:pointer}
input[type=range]::-moz-range-thumb{width:10px;height:10px;border-radius:50%;background:#fff;border:7px solid var(--teal);box-shadow:0 3px 10px rgba(23,62,77,.2);cursor:pointer}
.divider{height:1px;background:#dbe7e9;margin:25px 0 17px}.mode-heading{display:flex;align-items:end;justify-content:space-between;margin-bottom:6px}.mode-heading strong{font-size:15px}.mode-heading small{color:var(--muted);font-size:11px}
.switch-row{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:13px 0;border-bottom:1px solid #dbe7e9;cursor:pointer}.switch-row>span:first-child{display:flex;flex-direction:column;gap:3px}.switch-row strong{font-size:14px}.switch-row small{color:var(--muted);font-size:11px;line-height:1.45}
.switch-control{position:relative;display:block;flex:0 0 auto;width:48px;height:28px}.switch-control input{position:absolute;inset:0;width:100%;height:100%;margin:0;opacity:0;cursor:pointer}.switch-track{display:block;width:48px;height:28px;padding:3px;border-radius:999px;background:#c9d7da}.switch-track span{display:block;width:22px;height:22px;border-radius:50%;background:#fff;box-shadow:0 2px 7px rgba(23,62,77,.22);transition:transform .18s ease}.switch-control input:checked+.switch-track{background:var(--teal)}.belt-switch .switch-control input:checked+.switch-track{background:var(--orange)}.gear-switch .switch-control input:checked+.switch-track{background:var(--purple)}.switch-control input:checked+.switch-track span{transform:translateX(20px)}
.button-row{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-top:15px}.primary-button,.secondary-button{min-height:44px;padding:10px 14px;border-radius:12px;font-weight:850;cursor:pointer}.primary-button{grid-column:1/-1;border:0;background:var(--teal);color:#fff}.secondary-button{border:1px solid var(--line);background:#fff;color:var(--ink)}button:disabled{opacity:.46;cursor:not-allowed}button:focus-visible,input:focus-visible,a:focus-visible{outline:3px solid rgba(233,138,32,.42);outline-offset:3px}
.button-row.top-actions{margin:0 0 18px;padding-bottom:18px;border-bottom:1px solid #dbe7e9}
.experiment-topline{display:flex;align-items:center;justify-content:space-between;gap:14px;margin-bottom:13px}.status-badge{padding:8px 13px;border-radius:999px;font-size:13px;font-weight:850}.status-badge.ready{background:#eef5f6;color:#55737d}.status-badge.running{background:var(--teal-soft);color:var(--teal-dark)}.status-badge.paused{background:#fff6e6;color:#9b6416}
.canvas-wrap{position:relative;overflow:hidden;border:1px solid var(--line);border-radius:17px;background:#f8fbfb}.canvas-wrap canvas{display:block;width:100%;height:auto;aspect-ratio:1200/720}.canvas-tip{position:absolute;right:12px;bottom:10px;padding:6px 9px;border-radius:8px;background:rgba(255,255,255,.91);color:var(--muted);font-size:12px}
.formula-board{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:12px;padding:13px;border:1px solid #c9dadd;border-radius:15px;background:#f6fafa}.formula-board[hidden]{display:none}.formula-board>div{padding:12px 14px;border-radius:11px;background:#fff;border:1px solid #d7e4e6}.formula-board span,.formula-board small{display:block;color:var(--muted);font-size:12px}.formula-board strong{display:block;margin-top:6px;color:var(--teal-dark);font-size:18px;line-height:1.45}.formula-board small{margin-top:5px;line-height:1.45}.formula-note{grid-column:1/-1}.formula-switch .switch-control input:checked+.switch-track{background:var(--green)}
.quantity-panel,.relation-panel{margin-top:20px;padding:22px}.quantity-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:16px}.quantity-grid>div,.comparison-grid>div{padding:14px;border-radius:14px;background:#f6fafa;border:1px solid #d7e4e6}.quantity-grid span,.quantity-grid small,.comparison-grid span,.comparison-grid small{display:block;color:var(--muted);font-size:12px}.quantity-grid strong,.comparison-grid strong{display:block;margin:7px 0;font-size:18px;font-variant-numeric:tabular-nums}.quantity-grid small,.comparison-grid small{line-height:1.45}
.relation-heading{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:16px}.relation-formula{padding:10px 16px;border-radius:12px;background:var(--teal-soft);color:var(--teal-dark);font-size:21px;font-weight:900}.comparison-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}.result-card{background:#fff7e9!important;border-color:#efcf9e!important}.result-card strong{color:#a45d10}
@media(max-width:980px){.page-header{align-items:flex-start;flex-direction:column}.experiment-nav{justify-content:flex-start}.workspace{grid-template-columns:1fr}.control-panel{position:static}.quantity-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:640px){.page-shell{width:calc(100% - 18px);padding-top:18px}.control-panel,.experiment-panel,.quantity-panel,.relation-panel{padding:15px;border-radius:17px}.page-header p{font-size:15px}.quantity-grid,.comparison-grid,.formula-board{grid-template-columns:1fr}.formula-note{grid-column:auto}.relation-heading,.experiment-topline{align-items:flex-start;flex-direction:column}.button-row{grid-template-columns:1fr 1fr}.primary-button{grid-column:1/-1}}
@media(prefers-reduced-motion:reduce){.switch-track span{transition:none}}