.pc{--pc-green:#087d62;--pc-deep:#0d5946;--pc-ink:#17352d;--pc-muted:#537167;--pc-line:#d9e8e2;--pc-canvas:#f5fbf8;color:var(--pc-ink);font:16px/1.65 system-ui,-apple-system,"Segoe UI",sans-serif;max-width:1440px;margin:auto;padding:28px 28px 0}.pc *{box-sizing:border-box}.pc h1,.pc h2,.pc h3,.pc h4{color:var(--pc-ink);font-family:inherit;line-height:1.22}.pc h1{font-size:clamp(30px,4vw,46px);letter-spacing:-.045em;margin:8px 0 12px;font-weight:750}.pc h2{font-size:26px;letter-spacing:-.025em}.pc h3{font-size:18px}.pc p{margin:12px 0}.pc a{color:var(--pc-deep);text-underline-offset:4px}.pc a:focus-visible,.pc button:focus-visible,.pc input:focus-visible,.pc textarea:focus-visible,.pc summary:focus-visible{outline:3px solid #a86500;outline-offset:5px}.pc-eyebrow{text-transform:uppercase;letter-spacing:.12em;font-size:11px;font-weight:750;color:var(--pc-green);margin-bottom:8px}.pc-back{display:block;font-size:13px;margin-bottom:24px}.pc-heading{display:flex;justify-content:space-between;align-items:center;gap:24px;padding:8px 0 20px}.pc-heading p{color:var(--pc-muted)}.pc-course{padding:12px 18px;background:var(--pc-canvas);border:1px solid var(--pc-line);border-radius:12px;font-size:14px;text-decoration:none;flex-shrink:0}.pc-course span{display:block;font-size:11px}.pc-breadcrumb{display:flex;flex-wrap:wrap;gap:10px;padding:10px 0 22px;font-size:13px}.pc-workspace{border:1px solid var(--pc-line);border-radius:18px;overflow:hidden;display:grid;grid-template-columns:minmax(0,1fr) 390px;align-items:start}.pc-canvas{background:var(--pc-canvas);padding:24px;min-width:0;align-self:stretch}.pc-toolbar{display:flex;gap:16px;justify-content:space-between;font-size:13px;color:var(--pc-muted)}.pc-toolbar a{font-weight:650}.pc-graph{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:34px 26px;position:relative;padding:35px 0;min-height:480px;align-content:center}.pc-node{position:relative;z-index:1;background:white;border:1px solid #c8ddd3;border-radius:13px;padding:20px 10px;min-height:86px;text-align:center;text-decoration:none;display:flex;flex-direction:column;justify-content:center;font-size:15px;font-weight:650;box-shadow:0 4px 12px #17352d05}.pc-node small{font-size:11px;font-weight:400;margin-top:6px;color:var(--pc-muted)}.pc-mechanics{background:#fff4de;border-color:#e8d5ae}.pc-electricity{background:#eaf4fc;border-color:#c5deed}.pc-waves{background:#f2edfa;border-color:#dacfea}.pc-skills{background:#eaf4ef}.pc-selected{background:var(--pc-deep);color:white!important;border-color:var(--pc-deep)}.pc-selected small{color:#d2e9df}.pc-graph-focus{grid-template-columns:repeat(2,minmax(0,1fr));gap:34px 44px;min-height:320px}.pc-graph-focus .pc-selected{grid-column:1/-1;max-width:260px;width:100%;justify-self:center}.pc-edges{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.pc-edges line{stroke:#bbd3c7;stroke-width:2}.pc-edges line.pc-line-active{stroke:var(--pc-green);stroke-width:3}.pc-link-list{display:grid;gap:8px;margin:10px 0 24px}.pc-link-list h2{font-size:15px;color:var(--pc-muted);margin-bottom:6px}.pc-link-list a{display:block;padding:12px 14px;border:1px solid var(--pc-line);background:white;border-radius:9px;font-size:14px;text-decoration:none}.pc-link-list .pc-active-link{border-color:var(--pc-green);box-shadow:inset 4px 0 var(--pc-green)}.pc-legend{display:flex;flex-wrap:wrap;gap:10px 18px;color:var(--pc-muted);font-size:11px;margin-top:20px}.pc-legend span:nth-child(1){color:#865510}.pc-legend span:nth-child(2){color:#226898}.pc-legend span:nth-child(3){color:#7150a0}.pc-detail{padding:28px;border-left:1px solid var(--pc-line);background:white;min-width:0}.pc-detail:focus{outline:none}.pc-lead{color:var(--pc-muted);font-size:16px;line-height:1.7}.pc-detail section{padding-top:24px;margin-top:24px;border-top:1px solid var(--pc-line)}.pc-detail p,.pc-detail li{font-size:14px}.pc-equation{background:var(--pc-canvas);border-radius:12px;padding:20px 12px;font:21px/1.8 Georgia,serif;text-align:center;margin:22px 0;white-space:pre-wrap}.pc-steps{padding-left:23px}.pc-steps li{padding:0 0 12px 5px}.pc-condition{padding:18px;background:#fff8ea;border-left:3px solid #c28c35;border-radius:0 10px 10px 0;margin:20px 0}.pc-condition h3{font-size:14px}.pc-note{font-size:13px!important;color:var(--pc-muted)}.pc-parent-links{display:flex;flex-wrap:wrap;gap:14px;font-size:13px;margin:20px 0}.pc-outcomes,.pc-report{border-top:1px solid var(--pc-line);padding:18px 0;margin-top:20px;font-size:13px}.pc summary{cursor:pointer;min-height:30px}.pc-outcomes ul{padding-left:20px}.pc-outcomes li{margin:16px 0}.pc-outcomes strong{display:block}.pc-evidence{padding:17px;border:1px solid var(--pc-line);border-radius:12px;margin:15px 0}.pc-evidence h4{font-size:15px}.pc-evidence a{display:block;font-size:13px;margin:12px 0}.pc-tabs{display:flex;gap:8px;margin:16px 0}.pc-tabs a{border:1px solid var(--pc-line);padding:8px 20px;border-radius:24px;text-decoration:none;font-size:14px}.pc-tabs a[aria-current=page]{background:var(--pc-deep);color:white}.pc-practice-card{padding:18px;background:var(--pc-canvas);border-radius:12px;margin:16px 0}.pc-button{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:11px 17px;border-radius:9px;background:var(--pc-green);color:#fff!important;border:0;text-decoration:none;font:650 14px/1.5 system-ui;cursor:pointer;margin:10px 0}.pc-button:hover{background:#07664f}.pc-index{padding:38px 0}.pc-index-heading{display:flex;justify-content:space-between;align-items:center;gap:20px;margin-bottom:20px}.pc-index label{font-size:12px;color:var(--pc-muted)}.pc input,.pc textarea{border:1px solid #9fb6aa;border-radius:8px;padding:10px 12px;font:16px/1.5 system-ui;color:var(--pc-ink);background:white;max-width:100%}.pc-index input{display:block;min-width:260px}.pc-index-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:30px}.pc-index h3{font-size:15px}.pc-index ul{list-style:none;padding:0}.pc-index li{font-size:13px;padding:7px 0}.pc-index [hidden]{display:none}.pc-footnote{font-size:12px;color:var(--pc-muted);border-top:1px solid var(--pc-line);padding:20px 0}.pc-hub{max-width:1120px;padding-bottom:50px}.pc-hub h1{font-size:clamp(36px,6vw,68px);margin-top:20px}.pc-hub>.pc-lead{max-width:660px;font-size:19px}.pc-course-card{display:block;max-width:720px;padding:30px;border:1px solid var(--pc-line);background:var(--pc-canvas);border-radius:18px;margin:34px 0;text-decoration:none}.pc-course-card h2 span{float:right}.pc-course-card p{color:var(--pc-muted)}.pc-features{display:grid;grid-template-columns:repeat(3,1fr);gap:32px;margin:44px 0}.pc-features h2{font-size:19px}.pc-features span{font:24px Georgia;color:var(--pc-green)}.pc-features p{font-size:14px}.pc-question-layout{display:grid;grid-template-columns:minmax(0,780px) minmax(250px,340px);gap:30px;background:var(--pc-canvas);padding:30px;border-radius:16px;margin-bottom:40px}.pc-paper,.pc-membership{background:white;padding:28px;border:1px solid var(--pc-line);border-radius:12px;min-width:0}.pc-prompt{white-space:pre-wrap;margin:25px 0;line-height:1.8}.pc-paper img{max-width:100%;height:auto}.pc-paper figcaption{font-size:13px}.pc-membership{align-self:start}.pc-membership>a{display:block;margin-top:18px}.pc-membership p{font-size:14px}.pc-tags{display:flex;gap:7px;flex-wrap:wrap;margin:20px 0}.pc-tag{display:inline-block;padding:4px 8px;border-radius:5px;background:#eff5f1;font-size:12px}.pc-report label{display:block;margin:15px 0 8px}.pc-report textarea{width:100%}.pc-loading{opacity:.65}
.pc [tabindex="-1"]{scroll-margin-top:100px}.pc-practice-excerpt{display:-webkit-box;-webkit-line-clamp:6;-webkit-box-orient:vertical;overflow:hidden;white-space:pre-wrap}.pc-diagram{margin:22px 0}.pc-diagram img{display:block;max-width:100%;height:auto}.pc-diagram figcaption{font-size:13px}.pc-prompt,.pc-equation,.pc-paper pre,.pc-tag{overflow-wrap:anywhere}.pc .katex-display{max-width:100%;overflow-x:auto;overflow-y:hidden}.pc .pc-practice-card .katex{font-size:1em}
@media(min-width:1250px){.pc-canvas{padding:30px}.pc-graph{gap:40px 34px;min-height:620px}.pc-graph-focus{min-height:350px}}
@media(max-width:1050px){.pc-workspace{grid-template-columns:minmax(0,1fr) 340px}.pc-canvas{padding:18px}.pc-graph{gap:22px 12px}.pc-node{font-size:13px;padding:15px 7px}.pc-detail{padding:22px}.pc-index-grid{grid-template-columns:repeat(3,1fr)}}
@media(max-width:800px){.pc{padding:20px 16px 0}.pc-workspace{grid-template-columns:1fr}.pc-detail{border-left:0;border-top:1px solid var(--pc-line)}.pc-graph{min-height:0;gap:22px}.pc-node{font-size:14px}.pc-question-layout{grid-template-columns:1fr;padding:16px}.pc-index-grid{grid-template-columns:repeat(2,1fr)}.pc-course{font-size:12px}.pc-features{gap:18px}}
@media(max-width:480px){.pc-heading{display:block}.pc-course{display:inline-block;margin-top:12px}.pc h1{font-size:30px}.pc-workspace{border-radius:12px}.pc-graph{grid-template-columns:1fr 1fr;gap:14px;padding:25px 0}.pc-node{min-height:90px;font-size:13px}.pc-graph-focus{gap:25px 16px}.pc-legend{font-size:10px}.pc-index-heading{display:block}.pc-index label{display:block;margin-top:20px}.pc-index input{width:100%;min-width:0}.pc-index-grid{grid-template-columns:1fr 1fr;gap:24px 18px}.pc-paper,.pc-membership{padding:20px}.pc-question-layout{padding:10px;gap:18px}.pc-features{grid-template-columns:1fr}.pc-hub h1{font-size:42px}.pc-course-card{padding:22px}.pc-detail{padding:22px 18px}}
@media(prefers-reduced-motion:no-preference){.pc-node{transition:transform .18s,box-shadow .18s}.pc-node:hover{transform:translateY(-3px);box-shadow:0 6px 18px #17352d12}.pc-detail{animation:pc-enter .2s ease-out}@keyframes pc-enter{from{opacity:.7;transform:translateY(5px)}to{opacity:1;transform:none}}}