:root{
  --ink:#172033;
  --navy:#16243c;
  --blue:#286ba8;
  --blue-2:#5a9bd2;
  --blue-soft:#edf5fb;
  --cyan:#8dc8d4;
  --paper:#fbfcfe;
  --white:#fff;
  --muted:#68758a;
  --line:#dce4ed;
  --green:#257a5a;
  --green-soft:#eaf6f0;
  --amber:#9a671d;
  --amber-soft:#fff5df;
  --shadow:0 16px 45px rgba(30,61,91,.09);
  --serif:"LXGW WenKai Lite","Kaiti SC","STKaiti",KaiTi,serif;
  --sans:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",Arial,sans-serif;
}
*{box-sizing:border-box}
html{background:#f1f5f8;color:var(--ink);font-family:var(--sans);font-size:16px;line-height:1.55}
body{margin:0;min-height:100vh;background:
  linear-gradient(90deg,rgba(40,107,168,.035) 1px,transparent 1px),
  linear-gradient(rgba(40,107,168,.035) 1px,transparent 1px),#f5f8fa;background-size:42px 42px}
button,textarea{font:inherit}
button{color:inherit}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.hidden{display:none!important}
.topbar{height:78px;padding:0 30px;border-bottom:1px solid rgba(41,77,112,.15);background:rgba(250,252,253,.92);backdrop-filter:blur(12px);display:flex;align-items:center;justify-content:space-between;position:sticky;top:0;z-index:30}
.brand{display:flex;align-items:center;gap:12px;color:inherit;text-decoration:none}
.brand-mark{width:42px;height:42px;border-radius:12px;background:var(--navy);color:white;display:grid;place-items:center;font:800 14px Arial;letter-spacing:.08em;box-shadow:inset 0 -5px 0 rgba(141,200,212,.22)}
.brand strong{display:block;font:700 19px Arial;letter-spacing:.01em}
.brand small{display:block;color:var(--muted);font:700 13px var(--serif);margin-top:1px}
.top-actions{display:flex;align-items:center;gap:12px}
.prototype{display:flex;align-items:center;gap:7px;color:var(--muted);font-size:13px;font-weight:700}
.prototype i{width:8px;height:8px;border-radius:50%;background:#dc9a38;box-shadow:0 0 0 5px #f7ead3}
.quiet-button,.secondary-action{border:1px solid var(--line);background:#fff;border-radius:10px;padding:9px 14px;cursor:pointer;font-weight:700}
.nav-link{text-decoration:none;font-size:14px}
.quiet-button:hover,.secondary-action:hover{border-color:var(--blue);color:var(--blue)}
.shell{max-width:1540px;margin:0 auto;padding:24px 28px 70px;display:grid;grid-template-columns:320px minmax(0,1fr);gap:22px}
.rail{position:sticky;top:102px;align-self:start;background:rgba(255,255,255,.82);border:1px solid var(--line);border-radius:20px;box-shadow:var(--shadow);padding:20px}
.mentor-card{display:flex;gap:13px;padding:5px 4px 20px;border-bottom:1px solid var(--line)}
.mentor-avatar,.mini-avatar{flex:0 0 auto;display:grid;place-items:center;color:white;background:linear-gradient(145deg,var(--blue),var(--navy));font:800 14px Arial}
.mentor-avatar{width:48px;height:48px;border-radius:15px;box-shadow:0 8px 18px rgba(40,107,168,.2)}
.mentor-card h1{font:800 20px var(--serif);margin:1px 0 5px}
.mentor-card p{font-size:13px;color:var(--muted);margin:0;line-height:1.55}
.mentor-card .eyebrow{font-size:11px;margin:0;color:var(--blue);letter-spacing:.08em;text-transform:uppercase}
.rail-label,.section-label,.eyebrow{margin:0;color:var(--muted);font-size:12px;font-weight:800;letter-spacing:.04em}
.path-list{padding-top:18px;display:grid;gap:8px}
.path{width:100%;border:1px solid transparent;background:transparent;border-radius:13px;padding:12px 11px;display:grid;grid-template-columns:34px 1fr;gap:8px;text-align:left;cursor:pointer;transition:.18s}
.path:hover{background:#f3f7fa}.path.active{background:var(--blue-soft);border-color:#c9deee;box-shadow:inset 4px 0 var(--blue)}.path.agent-path{border-bottom:1px solid var(--line);border-radius:13px 13px 5px 5px;margin-bottom:4px}.path.agent-path.active{background:var(--navy);border-color:var(--navy);box-shadow:none;color:#fff}.path.agent-path.active small,.path.agent-path.active .path-index{color:#b8c9d9}
.path-index{font:700 11px Arial;color:#93a3b5;padding-top:3px}
.path b{display:block;font:800 15px var(--serif);margin-bottom:2px}.path small{display:block;color:var(--muted);font-size:12px}
.principle{margin-top:19px;padding:13px 14px;background:var(--navy);border-radius:13px;color:white}
.principle span{color:#96c9e2;font-size:11px;font-weight:800;letter-spacing:.08em}.principle p{font:700 14px var(--serif);margin:4px 0 0;line-height:1.65}
.workspace{min-width:0;display:grid;gap:16px}
.question-panel,.stage{background:rgba(255,255,255,.92);border:1px solid var(--line);border-radius:20px;box-shadow:var(--shadow)}
.question-panel{padding:25px 27px 20px;display:grid;grid-template-columns:minmax(220px,.8fr) minmax(480px,1.7fr);gap:22px;align-items:center}
.question-copy h2{font:800 clamp(23px,2vw,31px) var(--serif);margin:4px 0 5px}.question-copy>p:last-child{margin:0;color:var(--muted);font-size:14px}
.question-box{border:1px solid #bdd3e5;background:#f8fbfd;border-radius:15px;padding:10px;display:grid;grid-template-columns:1fr auto;gap:8px;align-items:end;box-shadow:0 0 0 5px rgba(40,107,168,.05)}
.question-box textarea{border:0;background:transparent;resize:none;min-height:58px;outline:0;padding:5px 7px;color:var(--ink);font-size:16px;line-height:1.6}
.question-box button,.primary-action{border:0;border-radius:10px;background:var(--blue);color:white;padding:11px 16px;font-weight:800;cursor:pointer;box-shadow:0 7px 16px rgba(40,107,168,.18);white-space:nowrap}
.question-box button:hover,.primary-action:hover{background:#205e95;transform:translateY(-1px)}
.examples{grid-column:1/-1;display:flex;align-items:center;gap:7px;flex-wrap:wrap;padding-top:2px}
.example-chip{border:1px solid var(--line);background:white;border-radius:999px;padding:6px 11px;cursor:pointer;color:#536379;font-size:13px}.example-chip:hover{border-color:#9dbed8;color:var(--blue);background:var(--blue-soft)}
.progress{display:grid;grid-template-columns:auto 1fr auto 1fr auto 1fr auto;align-items:center;padding:7px 15px;background:rgba(255,255,255,.72);border:1px solid var(--line);border-radius:14px}
.progress>i{height:1px;background:var(--line);min-width:10px}
.step{border:0;background:transparent;color:#7c8898;padding:7px 5px;cursor:pointer;font-size:12px;font-weight:700;white-space:nowrap}.step span{display:inline-grid;place-items:center;width:22px;height:22px;border-radius:50%;background:#e7edf2;margin-right:5px;font:700 11px Arial}.step.active{color:var(--blue)}.step.active span{background:var(--blue);color:white}.step.done{color:var(--green)}.step.done span{background:var(--green-soft);color:var(--green)}
.stage{padding:27px;min-height:440px}
.stage-head{display:flex;justify-content:space-between;align-items:center;gap:15px;padding-bottom:18px;border-bottom:1px solid var(--line)}
.stage-head>div{display:flex;align-items:center;gap:10px}.stage-head h2{font:800 24px var(--serif);margin:0}.stage-no{color:var(--blue);font:800 12px Arial;letter-spacing:.08em}
.status-chip{border-radius:999px;padding:5px 10px;font-size:12px;font-weight:800}.status-chip.blue{background:var(--blue-soft);color:var(--blue)}.status-chip.green{background:var(--green-soft);color:var(--green)}.status-chip.amber{background:var(--amber-soft);color:var(--amber)}
.main-question{margin:20px 0 17px;border-left:4px solid var(--blue);padding:10px 15px;background:#f5f9fc;border-radius:0 10px 10px 0}.main-question span{color:var(--muted);font-size:11px;font-weight:800}.main-question p{font:800 17px var(--serif);margin:3px 0 0}
.research-map{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;position:relative}
.map-card{position:relative;border:1px solid var(--line);border-radius:13px;padding:16px 14px;min-height:136px;background:white}.map-card:not(:last-child)::after{content:'→';position:absolute;right:-10px;top:49px;z-index:2;width:19px;height:25px;background:#fff;color:#8aa1b5;font-weight:800;text-align:center}.map-card span{font:800 11px Arial;color:var(--blue)}.map-card h3{font:800 17px var(--serif);margin:6px 0}.map-card p{font-size:13px;color:var(--muted);margin:0}
.mentor-line{display:flex;align-items:flex-start;gap:10px;margin-top:18px;padding:13px 15px;background:linear-gradient(90deg,#eef6fb,#f9fbfc);border-radius:12px}.mini-avatar{width:27px;height:27px;border-radius:9px;font-size:10px}.mentor-line p{margin:1px 0 0;font-size:14px;color:#41516a}
.stage>.primary-action{float:right;margin-top:18px}.stage-actions{display:flex;justify-content:space-between;align-items:center;margin-top:20px}.stage-actions .primary-action{margin-left:auto}
.evidence-layout{display:grid;grid-template-columns:minmax(0,1.65fr) minmax(250px,.72fr);gap:18px;margin-top:20px}
.claim-board,.evidence-guide,.thinking-rules{border:1px solid var(--line);border-radius:15px;padding:19px;background:#fff}.claim-board>h3{font:800 19px var(--serif);margin:5px 0 15px}.claim-state-row{display:flex;gap:6px;flex-wrap:wrap}.state-button{border:1px solid var(--line);background:#f8fafc;border-radius:8px;padding:7px 9px;display:flex;align-items:center;gap:6px;cursor:pointer;font-size:12px;font-weight:700}.state-button i{width:8px;height:8px;border-radius:50%}.state-button i.fact{background:#2c8b66}.state-button i.company{background:#528ec0}.state-button i.assumption{background:#7c65ad}.state-button i.inference{background:#c88728}.state-button i.conflicted{background:#c9534f}.state-button i.unknown{background:#969da7}.state-button.active{border-color:#8fb6d5;background:var(--blue-soft);color:var(--blue)}
.source-stack{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:14px}.source-card{border:1px solid var(--line);border-radius:12px;padding:14px;background:#fbfcfd}.source-card.primary-source{border-color:#b9d8ca;background:#f7fcf9}.source-top{display:flex;justify-content:space-between;gap:10px;font-size:11px;color:var(--muted)}.source-top b{color:var(--green)}.source-card h4{font:800 15px var(--serif);margin:9px 0 4px}.source-card p{font-size:12px;color:var(--muted);margin:0}.source-meta{display:flex;gap:10px;flex-wrap:wrap;margin-top:12px;padding-top:9px;border-top:1px solid var(--line);font-size:10px;color:#8390a1}
.evidence-guide{background:var(--navy);color:white;border:0}.evidence-guide .section-label{color:#9fc6df}.evidence-guide ol{list-style:none;padding:0;margin:14px 0 0;display:grid;gap:14px}.evidence-guide li{display:grid;grid-template-columns:26px 1fr;gap:8px;counter-increment:item}.evidence-guide ol{counter-reset:item}.evidence-guide li::before{content:counter(item);width:23px;height:23px;border-radius:8px;background:rgba(141,200,212,.16);color:#9ed1df;display:grid;place-items:center;font:800 10px Arial}.evidence-guide b{display:block;font:800 14px var(--serif)}.evidence-guide span{display:block;color:#b9c7d6;font-size:12px;margin-top:2px}
.thinking-layout{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(270px,.7fr);gap:18px;margin-top:20px}.thinking-layout>div:first-child{border:1px solid var(--line);border-radius:15px;padding:19px}.thinking-layout h3{font:800 19px var(--serif);margin:5px 0 13px}.student-answer,.mentor-response textarea{width:100%;resize:vertical;border:1px solid #cfdbe6;background:#fbfdfe;border-radius:11px;padding:12px 13px;outline:none;line-height:1.65}.student-answer:focus,.mentor-response textarea:focus{border-color:var(--blue);box-shadow:0 0 0 4px rgba(40,107,168,.08)}.answer-tools{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:10px}.answer-tools>span{color:var(--muted);font-size:12px}.thinking-rules{background:#f7fafc}.move-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:14px 0}.move-grid span{background:white;border:1px solid var(--line);border-radius:8px;padding:7px 8px;font-size:12px;font-weight:700}.thinking-rules>p:last-child{color:var(--muted);font-size:13px;margin:0}.mentor-response{margin-top:16px;border:1px solid #bcd5e8;background:linear-gradient(135deg,#eff7fc,#fbfdfe);border-radius:14px;padding:17px}.mentor-badge{display:inline-block;color:var(--blue);font-size:11px;font-weight:900;letter-spacing:.05em}.mentor-response>p{font:800 17px var(--serif);margin:7px 0 14px}.mentor-response label{display:block;color:var(--muted);font-size:12px;font-weight:800}.mentor-response label textarea{display:block;margin-top:5px;color:var(--ink);font-weight:400;font-size:14px}.mentor-response .primary-action{float:right;margin-top:10px}
.portfolio{display:grid;grid-template-columns:repeat(5,1fr);gap:10px;margin-top:21px}.portfolio article{min-height:180px;border:1px solid var(--line);border-radius:14px;padding:15px;background:#fbfcfd}.portfolio article.accent{background:var(--blue-soft);border-color:#c3dbea}.portfolio article>span{font:800 11px Arial;color:var(--blue)}.portfolio h3{font:800 16px var(--serif);margin:14px 0 7px}.portfolio p{font-size:12px;color:var(--muted);margin:0}.final-strip{margin-top:17px;background:var(--navy);color:white;border-radius:14px;padding:15px 17px;display:flex;justify-content:space-between;align-items:center;gap:15px}.final-strip b{font:800 15px var(--serif)}.final-strip p{color:#b9c8d8;font-size:12px;margin:2px 0 0}.final-strip .secondary-action{flex:0 0 auto}
.skill-dialog{width:min(900px,calc(100vw - 30px));max-height:86vh;padding:0;border:0;border-radius:20px;color:var(--ink);box-shadow:0 28px 90px rgba(17,32,51,.3)}.skill-dialog::backdrop{background:rgba(15,29,48,.65);backdrop-filter:blur(3px)}.dialog-head{position:sticky;top:0;background:white;border-bottom:1px solid var(--line);padding:18px 22px;display:flex;align-items:center;justify-content:space-between;z-index:1}.dialog-head h2{font:800 24px var(--serif);margin:2px 0 0}.dialog-head button{width:34px;height:34px;border:0;border-radius:9px;background:#eef3f7;cursor:pointer;font-size:22px}.dialog-body{padding:20px 22px 25px}.agent-summary{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:16px;border-radius:14px;background:var(--navy);color:white}.agent-name>span{color:#9bc9df;font:800 10px Arial;letter-spacing:.1em}.agent-name h3{font:800 18px var(--serif);margin:2px 0}.agent-name p{color:#b9c8d8;font-size:12px;margin:0}.agent-summary code{background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.15);border-radius:9px;padding:9px 11px;color:#d9eef7;font-size:12px}.contract-flow{display:flex;align-items:center;justify-content:center;gap:8px;flex-wrap:wrap;padding:17px 0;color:#536379;font-size:12px;font-weight:800}.contract-flow span{background:#f2f6f9;border-radius:8px;padding:6px 9px}.contract-flow i{font-style:normal;color:#9eb2c5}.skill-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}.skill-grid article{border:1px solid var(--line);border-radius:12px;padding:14px}.skill-grid b{font:800 15px var(--serif)}.skill-grid p{font-size:12px;color:var(--muted);margin:4px 0 0}.guardrails{margin-top:12px;border-left:4px solid #d59738;background:var(--amber-soft);padding:10px 13px;border-radius:0 9px 9px 0}.guardrails b{font:800 13px var(--serif)}.guardrails p{font-size:12px;color:#755528;margin:2px 0}.dialog-note{font-size:11px;color:#8792a1;margin:14px 0 0}
@media(max-width:1100px){.shell{grid-template-columns:1fr}.rail{position:static}.path-list{grid-template-columns:1fr 1fr}.principle{display:none}.question-panel{grid-template-columns:1fr}.examples{grid-column:auto}.portfolio{grid-template-columns:repeat(3,1fr)}}
@media(max-width:760px){.topbar{height:auto;padding:13px 15px}.prototype{display:none}.shell{padding:14px 12px 45px}.rail,.stage,.question-panel{border-radius:15px;padding:17px}.path-list{grid-template-columns:1fr}.question-box{grid-template-columns:1fr}.question-box button{width:100%}.progress{grid-template-columns:1fr 1fr;gap:4px}.progress>i{display:none}.step{text-align:left}.research-map,.source-stack,.thinking-layout,.evidence-layout,.portfolio,.skill-grid{grid-template-columns:1fr}.map-card:not(:last-child)::after{content:'↓';top:auto;bottom:-18px;left:50%;right:auto}.stage-head{align-items:flex-start}.status-chip{white-space:nowrap}.final-strip,.agent-summary{align-items:flex-start;flex-direction:column}.contract-flow{justify-content:flex-start}}