:root{--bg:#fbf9fb;--surface:#fff;--surface-soft:#f6f2f6;--ink:#34303a;--muted:#736b78;--line:#e6dce5;--plum:#8a6688;--plum-deep:#765273;--accent:#f2eaf3;--green:#377b65;--red:#a4535d;--max:1440px;--shadow:0 7px 24px rgba(55,38,55,.035)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--ink);font-family:system-ui,-apple-system,'Segoe UI',Arial,sans-serif;font-size:15px;line-height:1.58}button,input,textarea,select{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.55}a{color:var(--plum-deep)}:focus-visible{outline:3px solid #bc9cbd;outline-offset:3px}h1,h2,h3,p{margin-top:0}h1,h2,h3{line-height:1.24;letter-spacing:-.025em}h1{font-size:clamp(29px,3.1vw,43px);font-weight:710}h2{font-size:23px}h3{font-size:17px}.muted{color:var(--muted)}.eyebrow,.content-label,.lesson-kicker,.exercise-kicker{font-size:11px;font-weight:800;letter-spacing:.10em;text-transform:uppercase;color:var(--plum)}.tiny-note{font-size:12px;color:var(--muted);margin:10px 0}.spacer{flex:1}.topbar{height:70px;display:flex;gap:16px;align-items:center;background:rgba(251,249,251,.97);border-bottom:1px solid var(--line);padding:0 clamp(15px,3vw,38px);position:sticky;top:0;z-index:30;backdrop-filter:blur(16px)}.brand{display:flex;align-items:center;gap:11px;font-family:Georgia,serif;font-size:25px;font-weight:700;letter-spacing:-.05em;white-space:nowrap}.brand img{width:35px;height:35px}.brand sup{font-family:system-ui;font-size:9px;border:1px solid var(--line);padding:3px 5px;border-radius:6px;vertical-align:super;letter-spacing:0;color:var(--muted)}.test-pill{border:1px solid #e3d7ba;background:#faf5e8;font-size:10px;color:#856744;border-radius:999px;padding:5px 10px;font-weight:700;letter-spacing:.04em}.datetime{color:var(--muted);font-size:12px}.save-status{font-size:12px;color:var(--green);white-space:nowrap}.icon-btn{border:1px solid transparent;background:transparent;border-radius:10px;padding:8px 12px;color:var(--ink);font-size:21px}.icon-btn:hover{background:var(--accent)}.drawer-overlay{position:fixed;inset:70px 0 0;background:#392b3a66;z-index:20}.drawer{position:fixed;top:70px;bottom:0;left:0;width:min(310px,90vw);background:white;border-right:1px solid var(--line);transform:translateX(-102%);transition:transform .2s ease;z-index:25;display:flex;flex-direction:column;box-shadow:12px 0 35px #00000009}.drawer.visible{transform:none}.drawer-kicker,.nav-title{font-size:11px;color:var(--muted);font-weight:800;letter-spacing:.08em;margin:22px 20px 9px}.drawer nav{padding:8px;overflow:auto}.drawer nav button{width:100%;text-align:left;padding:12px 13px;display:flex;align-items:center;gap:11px;border:0;background:transparent;border-radius:10px;color:var(--ink);font-weight:560}.drawer nav button:hover{background:var(--accent)}.drawer nav button>span:first-child{color:var(--plum);display:inline-grid;place-items:center;width:27px;font-size:21px}.drawer-note{font-size:11px;color:var(--muted);margin:auto 17px 20px;padding-top:20px}.workspace{max-width:var(--max);margin:0 auto;padding:44px clamp(18px,4vw,55px) 110px}.page-heading{margin:0 0 32px}.page-heading h1{margin:6px 0 10px}.page-heading p{color:var(--muted);max-width:760px;margin:0}.home-grid{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(280px,1fr);gap:20px;margin-bottom:36px}.hero-panel,.side-panel,.panel,.course-card,.quick-section,.subject-overview{border:1px solid var(--line);border-radius:20px;background:var(--surface);box-shadow:var(--shadow)}.hero-panel{background:linear-gradient(118deg,#f2e8f1,#fcfafc);padding:clamp(25px,3vw,42px);min-height:220px}.hero-panel h2{font-size:clamp(24px,2.5vw,34px);margin:16px 0 10px}.hero-panel p{color:var(--muted)}.side-panel{padding:25px}.section-head{display:flex;align-items:center;justify-content:space-between;gap:16px;margin:28px 0 16px}.section-head h2,.section-head h3{margin:0}.section-head h3{font-size:17px}.term-line{padding:12px 0;display:flex;justify-content:space-between;gap:10px;border-top:1px solid var(--line);font-size:12px}.term-line span{display:grid}.term-line small{color:var(--muted)}.term-line strong{color:var(--plum)}.course-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(270px,1fr));gap:18px}.course-card{padding:26px;min-height:232px;display:flex;flex-direction:column;align-items:flex-start}.subject-symbol{width:48px;height:48px;border-radius:14px;display:grid;place-items:center;font-family:Georgia,serif;font-size:24px;font-weight:bold;margin-bottom:14px}.math-color{background:#eee7f2;color:#745882}.language-color{background:#e9f0e9;color:#527762}.course-card h3{margin:7px 0 21px;font-size:20px}.progress-rail,.tiny-progress{width:100%;height:7px;border-radius:20px;background:#eee7ee;overflow:hidden}.progress-rail>span,.tiny-progress>span{display:block;height:100%;border-radius:20px;background:linear-gradient(90deg,#a98ba8,#876c8b)}.card-bottom{width:100%;display:flex;align-items:center;justify-content:space-between;gap:10px;color:var(--muted);font-size:12px;margin-top:15px}.quick-section,.panel{padding:25px;margin-top:24px}.quick-section{margin-top:35px}.quick-section>.section-head{margin-top:0}.btn-primary,.btn-outline,.btn-quiet,.btn-text{border-radius:11px;padding:10px 16px;font-weight:660;font-size:13px;border:1px solid transparent;display:inline-flex;align-items:center;gap:6px;justify-content:center;max-width:100%;text-align:center}.btn-primary{background:var(--plum-deep);color:white}.btn-primary:hover{background:#654261}.btn-outline{background:white;border-color:#cfbecf;color:var(--plum-deep)}.btn-outline:hover{background:var(--accent)}.btn-quiet{background:var(--surface-soft);color:var(--plum-deep)}.btn-quiet:hover{background:#eee3ef}.btn-text{padding:6px 0;color:var(--plum-deep);background:transparent;font-weight:700}.btn-text:hover{text-decoration:underline}.inline-notice{padding:17px 20px;background:#f5f0e8;color:#695d4b;border:1px solid #e9dfd0;border-radius:14px;margin:28px 0;font-size:13px}.subject-overview{padding:25px;display:flex;align-items:center;gap:32px;margin-bottom:36px}.subject-overview>div{min-width:160px}.subject-overview p{margin:0;color:var(--muted)}.big-number{font-size:44px;font-weight:800;color:var(--plum-deep)}.big-number small{font-size:17px;color:var(--muted)}.part-section{margin:32px 0}.lesson-list{border:1px solid var(--line);background:var(--surface);border-radius:17px;overflow:hidden}.lesson-row{padding:16px 20px;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:16px}.lesson-row:last-child{border:0}.lesson-index{font-size:12px;border-radius:9px;padding:7px;background:var(--accent);color:var(--plum-deep);min-width:45px;text-align:center;font-weight:760}.lesson-detail{display:grid;gap:3px;flex:1;min-width:0}.lesson-detail strong{font-size:14px}.lesson-detail>span{font-size:11px;color:var(--muted)}.tiny-progress{width:80px;flex-shrink:0;height:5px}.lesson-workspace{max-width:1570px;margin:auto;padding:18px clamp(12px,2.5vw,32px) 80px}.lesson-banner{display:flex;align-items:center;gap:20px;border-bottom:1px solid var(--line);padding:0 0 15px;margin-bottom:22px;font-size:12px}.lesson-layout{display:grid;grid-template-columns:minmax(235px,290px) minmax(0,1fr);align-items:start;gap:22px}.module-nav{background:white;border:1px solid var(--line);border-radius:19px;padding:20px;position:sticky;top:90px;max-height:calc(100vh - 106px);overflow:auto}.module-nav h3{font-size:16px;margin:10px 0 15px}.module-nav .progress-rail{margin-bottom:17px}.module-nav-btn{width:100%;background:none;border:0;border-radius:10px;text-align:left;display:flex;align-items:start;gap:9px;padding:12px 8px;color:var(--muted);font-size:12px;line-height:1.35}.module-nav-btn:hover{background:var(--surface-soft)}.module-nav-btn.active{background:var(--accent);color:var(--ink);font-weight:700}.module-step{background:#f5f0f5;color:var(--plum);border-radius:7px;min-width:23px;height:23px;display:grid;place-items:center;font-size:11px;flex-shrink:0}.module-nav-btn.active .module-step{background:#d8c7d8;color:var(--plum-deep)}.lesson-sheet{border:1px solid var(--line);border-radius:21px;padding:clamp(24px,3.6vw,52px);background:white;min-width:0}.lesson-sheet>h1{font-size:clamp(26px,2.7vw,35px);margin:13px 0}.lesson-goal{color:var(--muted);font-size:14px;max-width:850px}.lesson-elements{margin-top:33px}.content-block{margin:27px 0;padding:0 0 12px;max-width:920px}.content-block h3{font-size:18px;margin:8px 0}.content-label{margin-bottom:9px}.block-definition,.block-theorem,.block-proof,.block-remember{border-left:4px solid #b59bb7;background:#faf8fa;padding:18px 22px;border-radius:0 13px 13px 0}.block-worked,.block-worked_example{background:#f5eff5;border-left:4px solid #a486a8;padding:19px 24px;border-radius:0 12px 12px 0}.block-lead{border-left:3px solid #98ad9d;padding-left:20px}.block-reflection_text{background:#f8f6ee;padding:20px;border-radius:12px}.prose{font-size:15px;line-height:1.85;word-break:normal;overflow-wrap:anywhere}.prose p:last-child{margin-bottom:0}.prose h4,.prose h5{font-size:16px}.prose ul{padding-left:23px}.prose code,.exercise code{background:#f0edf0;border-radius:4px;padding:2px 4px}.diagram-figure{border:1px solid var(--line);border-radius:14px;text-align:center;margin:28px 0;padding:19px;overflow:hidden}.diagram-figure img{max-width:100%;height:auto;max-height:570px}.diagram-figure figcaption{color:var(--muted);font-size:12px;margin-top:9px}.unavailable-figure{padding:25px;border:1px dashed var(--line);color:var(--muted);font-size:12px}.module-bottom{margin-top:45px;padding-top:24px;border-top:1px solid var(--line);display:flex;flex-wrap:wrap;justify-content:space-between;align-items:end;gap:18px}.module-arrows{display:flex;gap:10px;flex-wrap:wrap}.exercise{margin:23px 0;background:#fff;border:1px solid #dbd2db;border-left:4px solid #af95b1;border-radius:13px;padding:20px 22px;max-width:940px}.exercise-top{display:flex;align-items:center;gap:10px;justify-content:space-between}.exercise-prompt{font-size:15px;font-weight:580;line-height:1.7;margin:13px 0 19px}.exercise-prompt p:last-child{margin-bottom:0}.option-list{display:grid;gap:9px}.option{border:1px solid var(--line);border-radius:10px;display:flex;gap:12px;padding:10px 13px;align-items:center;cursor:pointer}.option:hover{background:#fcf9fc}.option input{accent-color:var(--plum-deep);flex-shrink:0}.option p{margin:0}.exercise-actions{margin-top:18px;display:flex;gap:9px;flex-wrap:wrap}.matching{display:grid;gap:9px}.match-row{display:flex;gap:12px;align-items:center;justify-content:space-between;background:var(--surface-soft);padding:12px 14px;border-radius:10px}.match-row span{flex:1;min-width:0}.match-row span p{margin:0}.match-row select{width:min(42%,340px);min-width:140px}.matching select,.field-input,.planner-form input,.planner-form select,.settings-grid textarea{border:1px solid #d8ccd8;background:white;color:var(--ink);padding:10px 12px;border-radius:9px}.token-group{display:flex;flex-wrap:wrap;gap:7px;background:var(--surface-soft);padding:20px;border-radius:10px}.token{border:1px solid #d8ccd8;background:white;border-radius:8px;padding:8px 11px;min-height:35px;color:var(--ink)}.token[aria-pressed=true]{background:#e0cfe0;border-color:#9d799d;box-shadow:0 0 0 2px #e0cfe0}.tf-list{display:grid;gap:8px}.tf-row{display:flex;gap:14px;justify-content:space-between;align-items:center;padding:11px 13px;background:var(--surface-soft);border-radius:9px}.tf-row span{flex:1}.tf-row span p{margin:0}.tf-picks{display:flex;gap:13px;white-space:nowrap}.tf-picks label{cursor:pointer}.tf-picks input{accent-color:var(--plum)}.order-list{display:grid;gap:7px}.order-row{display:flex;align-items:center;justify-content:space-between;gap:12px;background:var(--surface-soft);border:1px solid var(--line);border-radius:9px;padding:8px 9px 8px 15px}.order-text{flex:1}.order-text p{margin:0}.order-buttons{display:flex;gap:5px}.order-buttons button{border:1px solid var(--line);border-radius:7px;background:white;padding:6px 11px;font-weight:700}.field-label{display:block;margin:15px 0 8px;font-weight:650;font-size:13px}.field-input{width:min(100%,500px)}.text-work{width:100%;padding:16px;border:1px solid #d4c8d4;border-radius:10px;resize:vertical;min-height:150px;background:#fff}.oral-controls{display:flex;gap:10px;align-items:center;flex-wrap:wrap;padding:10px;background:#f7f3f8;border-radius:10px}.oral-note{color:var(--muted);font-size:12px;flex:1}.feedback{margin-top:16px;padding:15px 17px;border-radius:10px;font-size:13px}.feedback strong{display:block;margin-bottom:5px}.feedback p:last-child{margin:0}.feedback.success{border:1px solid #c3dece;background:#eff8f2;color:#285b41}.feedback.error{border:1px solid #ead0d2;background:#fff5f5;color:#873f49}.feedback.hint{border:1px solid #e5dbba;background:#fffbec;color:#705b32}.feedback.model{border:1px solid #dfd3df;background:#f9f6fa;color:var(--ink)}.criteria{padding-left:20px}.self-rating{display:flex;align-items:center;gap:8px;flex-wrap:wrap;border-top:1px solid var(--line);margin-top:17px;padding-top:16px;font-size:12px}.self-rating>span{margin-right:7px;font-weight:700}.self-rating button{border:1px solid #cfbfce;background:white;padding:8px 11px;border-radius:8px;font-size:12px;color:var(--plum-deep)}.self-rating button.selected{background:#eaddea;border-color:#aa8eaa}.status-good{color:var(--green);font-size:11px}.status-subtle{color:var(--muted);font-size:11px}.review-line{padding:17px;background:white;border:1px solid var(--line);border-radius:12px;display:flex;align-items:center;gap:14px;justify-content:space-between;margin:10px 0}.review-line p{font-size:12px;color:var(--muted);margin:3px 0 0}.planner-form{display:grid;grid-template-columns:1.6fr 1fr 1fr auto;align-items:end;gap:15px}.planner-form label{display:grid;gap:6px;font-size:12px;font-weight:650}.planner-item{display:flex;justify-content:space-between;align-items:center;padding:13px 18px;border-bottom:1px solid var(--line);gap:10px}.planner-item.done{opacity:.65}.planner-item.done b{text-decoration:line-through}.planner-item>label{display:flex;align-items:center;gap:12px;flex:1}.planner-item span{display:grid}.planner-item small{font-size:11px;color:var(--muted)}.planner-item>span{font-size:12px;color:var(--plum)}.settings-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:20px}.settings-grid .panel{margin:0}.settings-grid .panel h2{font-size:19px}.settings-grid .panel p{color:var(--muted);font-size:13px}.settings-grid textarea{width:100%;margin:9px 0}.settings-grid details{margin-top:13px}.upload{display:block;border:1px dashed #ae95ae;border-radius:12px;padding:18px;margin:16px 0;cursor:pointer;text-align:center;color:var(--plum-deep);font-weight:700}.upload.alt{font-size:12px}.upload input{display:block;margin:10px auto;width:100%;max-width:290px;font-size:11px}.checkbox-line{display:flex;gap:10px;align-items:center;font-size:12px;margin:12px 0}.source-item{display:flex;gap:10px;align-items:center;justify-content:space-between;border-top:1px solid var(--line);padding:10px 0;font-size:12px}.source-item span{min-width:0;overflow-wrap:anywhere}.source-item a{white-space:nowrap}.empty-state{background:white;border:1px solid var(--line);padding:35px;color:var(--muted);border-radius:14px}.loading-page{max-width:900px;padding:70px;margin:auto;color:var(--muted)}#toastHost{position:fixed;right:24px;bottom:24px;z-index:90;display:grid;gap:8px}.toast{padding:12px 18px;border-radius:10px;background:#3d3941;color:white;box-shadow:0 12px 30px #0003;font-size:13px}.toast.error{background:#a4535d}
@media(max-width:1030px){.lesson-layout{grid-template-columns:minmax(0,1fr)}.module-nav{position:relative;top:auto;max-height:200px;display:block}.module-nav-btn{display:inline-flex;width:auto;max-width:210px;vertical-align:top}.module-nav .progress-rail{margin:0}.module-nav .eyebrow,.module-nav h3{display:none}.home-grid{grid-template-columns:1fr}.planner-form{grid-template-columns:1fr 1fr}}
@media(max-width:640px){.topbar{height:61px;gap:8px}.brand{font-size:21px}.brand img{width:28px;height:28px}.datetime{display:none}.test-pill{font-size:9px;padding:4px 7px}.save-status{font-size:10px}.drawer{top:61px}.drawer-overlay{top:61px}.workspace{padding:29px 15px 100px}.home-grid{gap:12px}.hero-panel,.side-panel,.quick-section,.panel{padding:20px}.course-card{padding:20px}.lesson-row{padding:14px 11px;gap:9px;flex-wrap:wrap}.lesson-detail{flex-basis:55%}.lesson-index{min-width:40px}.lesson-row .tiny-progress{display:none}.lesson-workspace{padding:10px 10px 80px}.lesson-banner{flex-wrap:wrap;gap:6px}.module-nav{padding:12px}.module-nav-btn{max-width:150px}.lesson-sheet{padding:22px 15px}.exercise{padding:16px 13px}.match-row{flex-direction:column;align-items:stretch}.match-row select{width:100%}.module-bottom{align-items:stretch}.module-bottom>div{width:100%}.module-arrows{justify-content:space-between}.planner-form{grid-template-columns:1fr}.subject-overview{flex-wrap:wrap}.settings-grid{grid-template-columns:minmax(0,1fr)}.tf-row{align-items:start}.tf-picks{gap:7px}}

.note-action{border:0;background:transparent;color:var(--plum);font-size:11px;margin:10px 0 0;padding:5px 0}.note-action:hover{text-decoration:underline}.comparison{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:18px}.comparison>div{min-width:0;background:white;border:1px solid var(--line);border-radius:9px;padding:12px;overflow-wrap:anywhere}.comparison b{font-size:12px;color:var(--plum)}.comparison p{font-weight:400}@media(max-width:700px){.comparison{grid-template-columns:1fr}}

.workshop-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.workshop-grid .panel{margin:0}.workshop-grid textarea,.workspace .panel textarea[data-workshop]{width:100%;border:1px solid var(--line);border-radius:11px;padding:15px;color:var(--ink);background:white;resize:vertical}.workshop-grid .panel p{color:var(--muted);font-size:12px}.diff-content{background:#faf9fa;border:1px solid var(--line);border-radius:10px;padding:20px;white-space:pre-wrap;overflow-wrap:anywhere;line-height:2}.diff-content ins{background:#d9efdf;color:#23583b;text-decoration:none}.diff-content del{background:#f6dadd;color:#934a50;text-decoration:line-through}@media(max-width:850px){.workshop-grid{grid-template-columns:1fr}}
/* Context-specific module picker: collapsible, leaving full width to the lesson. */
.lesson-layout{grid-template-columns:minmax(0,1fr)}
.module-nav{position:relative;top:auto;max-height:none;overflow:visible;padding:0}
.module-nav summary{cursor:pointer;padding:14px 18px;font-weight:700;color:var(--plum-deep);font-size:13px}
.module-nav summary::marker{color:var(--plum)}
.module-nav-content{padding:0 16px 16px;display:flex;gap:6px;flex-wrap:wrap}
.module-nav-content .eyebrow,.module-nav-content>h3,.module-nav-content>.progress-rail{display:none}
.module-nav-btn{display:flex;width:auto;max-width:310px;padding:10px 12px}
@media(max-width:1030px){.module-nav{max-height:none}.module-nav-btn{max-width:260px}}
@media(max-width:640px){.module-nav{padding:0}.module-nav-btn{max-width:100%;width:100%}}