:root{--bg:#f5f6f0;--paper:#fffefb;--ink:#173a30;--text:#293d35;--muted:#65746a;--green:#176848;--dark:#134d36;--lime:#d8ef9b;--line:#dce3d7;--soft:#edf4e8;--orange:#c25b2f;--sand:#fcf0df;--radius:22px;--shadow:0 8px 30px #193c2910}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font-family:Arial,Helvetica,sans-serif;line-height:1.55;font-size:16px}button,input,textarea,select{font:inherit}button,a,input,textarea,summary{touch-action:manipulation}button,a{ -webkit-tap-highlight-color:transparent}a{color:var(--green)}button{cursor:pointer}button:disabled{cursor:default;opacity:.52}button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible,summary:focus-visible{outline:3px solid #f0b94b;outline-offset:3px}button{border:0}h1,h2,h3,p{margin:0}h1{font-size:clamp(31px,4.3vw,58px);line-height:1.07;letter-spacing:-1.9px;color:var(--ink);font-weight:750}h2{font-size:25px;line-height:1.2;letter-spacing:-.6px;color:var(--ink)}h3{font-size:18px;line-height:1.3;color:var(--ink)}.shell{max-width:1240px;padding:0 32px;margin:auto}.site-header{height:84px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);gap:16px}.brand{display:flex;align-items:center;gap:11px;border:0;background:transparent;padding:0;color:var(--ink);text-align:left}.brand-mark{display:grid;place-items:center;width:42px;height:42px;border-radius:12px;background:var(--green);color:white;font-size:26px;font-weight:bold}.brand-name{font-size:20px;font-weight:bold;letter-spacing:-.6px}.brand-sub{display:block;font-size:11px;letter-spacing:1.5px;font-weight:normal;color:var(--muted);line-height:1.2}.nav{display:flex;align-items:center;gap:10px}.nav button{background:transparent;padding:10px 14px;color:var(--muted);border-radius:12px;font-size:14px}.nav button:hover{background:var(--soft);color:var(--ink)}.tag{display:inline-flex;align-items:center;gap:7px;padding:6px 10px;font-size:11px;font-weight:bold;letter-spacing:1px;text-transform:uppercase;border-radius:100px;background:var(--soft);color:var(--green)}.dot{width:6px;height:6px;border-radius:50%;background:var(--green)}main{min-height:calc(100vh - 180px)}.hero{display:grid;grid-template-columns:1.4fr 1fr;gap:60px;align-items:center;padding:50px 0 38px}.hero h1{margin:19px 0 20px}.hero p{max-width:570px;color:var(--muted);font-size:17px}.hero-visual{position:relative;height:245px;background:#e3ecd8;border:1px solid #d2dfc4;border-radius:30px;overflow:hidden}.hero-visual svg{height:100%;width:100%}.visual-caption{position:absolute;bottom:16px;left:20px;font-size:12px;letter-spacing:1px;color:var(--green)}.meta-line{display:flex;gap:30px;margin-top:24px;font-size:12px;color:var(--muted)}.meta-line strong{display:block;font-size:25px;color:var(--ink);font-weight:600}.section-title{display:flex;align-items:baseline;justify-content:space-between;gap:20px;margin:16px 0 20px}.section-title p{font-size:13px;color:var(--muted)}.course-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.course{background:var(--paper);border:1px solid var(--line);border-radius:var(--radius);padding:23px;display:flex;flex-direction:column;position:relative;min-height:230px}.course:hover{box-shadow:var(--shadow);border-color:#b6c9b1}.course-top{display:flex;align-items:center;gap:14px;margin-bottom:14px}.grade-badge{font-size:32px;line-height:1;letter-spacing:-1px;background:var(--soft);color:var(--green);width:58px;height:58px;display:grid;place-items:center;border-radius:17px}.course.advanced .grade-badge{background:#f4ebd9;color:#8b5e21}.eyebrow{font-size:11px;letter-spacing:1.2px;text-transform:uppercase;color:var(--muted);font-weight:bold}.course h3{font-size:20px;margin:4px 0}.course p{font-size:13px;color:var(--muted);margin-bottom:18px}.course-meta{margin-top:auto;color:var(--muted);font-size:12px;display:flex;align-items:center;justify-content:space-between}.course .btn{margin-top:15px}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:10px 17px;border-radius:12px;background:var(--green);color:white;text-decoration:none;font-weight:bold;font-size:14px;border:1px solid var(--green);line-height:1.4}.btn:hover{background:var(--dark)}.btn.secondary{background:transparent;color:var(--green);border-color:#b9cbb5}.btn.secondary:hover{background:var(--soft)}.btn.tertiary{background:var(--soft);color:var(--green);border-color:transparent}.btn.small{min-height:36px;padding:7px 12px;font-size:12px}.btn.full{width:100%}.btn.warn{background:#fff3e9;color:#985020;border-color:#f0d5ba}.arrow{font-size:18px;margin-left:auto}.info-strip{margin:28px 0;background:var(--soft);padding:20px 24px;border-radius:18px;display:flex;gap:24px;align-items:center}.info-strip p{font-size:13px;color:var(--muted);max-width:900px}.info-strip strong{color:var(--green)}.footer{padding:25px 0;border-top:1px solid var(--line);margin-top:38px;font-size:12px;color:var(--muted);display:flex;justify-content:space-between;gap:16px}.footer button{border:0;color:var(--muted);padding:0;background:transparent;text-decoration:underline;font-size:12px}.crumb{margin:22px 0 17px;display:flex;gap:9px;align-items:center;flex-wrap:wrap;font-size:12px;color:var(--muted)}.crumb button{background:transparent;color:var(--green);padding:3px 0;font-size:12px}.route-head{display:flex;justify-content:space-between;gap:30px;align-items:center;background:var(--ink);color:#e5efdf;border-radius:24px;padding:30px;margin-bottom:25px}.route-head h1{font-size:34px;color:#fffef8;margin:8px 0 12px;letter-spacing:-1px}.route-head p{font-size:14px;max-width:580px;color:#d8e4d1}.route-head .eyebrow{color:var(--lime)}.route-head .btn{background:var(--lime);color:var(--ink);border-color:var(--lime);white-space:nowrap}.route-stats{text-align:right;min-width:135px}.route-stats b{display:block;font-size:33px;line-height:1.2;color:var(--lime)}.route-stats small{font-size:12px;color:#d8e4d1}.progress-track{height:6px;border-radius:6px;background:#e1e8db;overflow:hidden}.progress-fill{height:100%;background:var(--green);border-radius:6px}.route-head .progress-track{margin-top:10px;background:#456451}.route-head .progress-fill{background:var(--lime)}.route-actions{display:flex;gap:10px;flex-wrap:wrap;margin:20px 0 28px}.lesson-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.lesson-card{display:flex;gap:16px;align-items:center;border:1px solid var(--line);border-radius:17px;background:var(--paper);padding:17px;text-align:left;color:var(--text);width:100%}.lesson-card:hover{border-color:var(--green);box-shadow:var(--shadow)}.lesson-num{display:grid;place-items:center;flex-shrink:0;width:39px;height:39px;border-radius:11px;background:var(--soft);color:var(--green);font-size:14px;font-weight:bold}.lesson-card h3{font-size:16px}.lesson-card p{font-size:12px;color:var(--muted);margin:3px 0}.lesson-card .arrow{color:var(--green)}.work-grid{display:grid;grid-template-columns:248px minmax(0,1fr);gap:24px;align-items:start}.side{position:sticky;top:18px;background:var(--paper);border:1px solid var(--line);border-radius:20px;padding:17px;max-height:90vh;overflow-y:auto}.side-title{font-size:14px;font-weight:bold;color:var(--ink);margin-bottom:12px}.side button{display:flex;gap:8px;align-items:baseline;width:100%;background:transparent;padding:9px 9px;text-align:left;border-radius:8px;font-size:12px;color:var(--muted);line-height:1.4}.side button.active{background:var(--soft);color:var(--green);font-weight:bold}.side button:hover{background:var(--soft)}.side small{flex-shrink:0;width:18px;color:#85977e}.lesson-content{min-width:0}.lesson-heading h1{font-size:29px;letter-spacing:-.9px;margin:4px 0 8px}.lesson-heading p{font-size:14px;color:var(--muted)}.lesson-heading .eyebrow{font-size:10px}.theory{margin:16px 0;border:1px solid var(--line);border-radius:15px;background:#eef4e9;overflow:hidden}.theory summary{padding:12px 17px;cursor:pointer;font-weight:bold;font-size:13px;color:var(--green)}.theory-inside{padding:0 17px 18px;font-size:14px}.theory-inside p{margin:8px 0}.theory-inside ol{padding-left:20px;margin:10px 0}.worked-example{padding:14px;background:#fffefa;border-radius:12px;margin-top:12px}.worked-example h3{font-size:14px;margin-bottom:6px}.toolbar{display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px;margin:16px 0}.segmented{display:flex;padding:3px;background:#e6ebdf;border-radius:11px;gap:2px}.segmented button{background:transparent;border-radius:8px;padding:7px 12px;font-size:12px;color:var(--muted);min-height:35px}.segmented button.selected{background:var(--paper);box-shadow:0 2px 5px #0000000a;color:var(--green);font-weight:bold}.task-tabs{display:flex;gap:6px;align-items:center;flex-wrap:wrap}.task-tab{width:34px;height:34px;border-radius:10px;background:var(--paper);border:1px solid var(--line);color:var(--muted);font-size:13px}.task-tab.active{background:var(--green);color:white;border-color:var(--green)}.task-tab.completed:not(.active){background:#e2efd6;color:var(--green);border-color:#bbd2ab}.task-card{background:var(--paper);border:1px solid var(--line);border-radius:20px;padding:24px;box-shadow:var(--shadow)}.task-top{display:flex;justify-content:space-between;gap:15px;align-items:center;margin-bottom:11px}.task-level{font-size:10px;text-transform:uppercase;letter-spacing:1px;color:var(--green);font-weight:bold}.task-index{font-size:11px;color:var(--muted)}.task-prompt{font-size:18px;line-height:1.55;color:var(--ink);white-space:pre-line}.diagram{margin-top:15px;display:flex;justify-content:center;overflow:hidden;border-radius:12px;background:#f6f8f2}.diagram svg{display:block;max-width:100%;height:auto;max-height:230px}.mode-note{font-size:11px;color:var(--muted);margin:13px 2px}.steps{display:flex;flex-direction:column;gap:12px}.step{border:1px solid var(--line);border-radius:16px;padding:18px;background:var(--paper)}.step.current{border-color:#acc6a4}.step.done{background:#edf5e7;border-color:#d1e2c4;padding:13px 17px}.step.done.assisted{background:#fbf3e8;border-color:#eddfcb}.step-head{display:flex;align-items:center;gap:9px;font-size:10px;text-transform:uppercase;letter-spacing:1px;color:var(--green);font-weight:bold;margin-bottom:8px}.step-head .number{display:grid;place-items:center;background:var(--green);color:white;width:20px;height:20px;border-radius:50%;font-size:10px}.step h3{font-size:16px;line-height:1.5;font-weight:500;white-space:pre-line}.step.done h3{font-size:13px}.correct-answer{color:var(--green);font-size:14px;font-weight:bold;margin:5px 0}.solution-note{font-size:12px;color:var(--muted);white-space:pre-line}.answer-form{margin-top:13px;display:flex;gap:10px;align-items:start;flex-wrap:wrap}.answer-input{width:min(100%,260px);min-width:120px;min-height:45px;border:1px solid #b6c8af;border-radius:11px;padding:10px 12px;background:#fff;color:var(--text);font-size:17px}.format-help{font-size:11px;color:var(--muted);margin-top:6px}.choices{display:flex;flex-direction:column;gap:8px;margin:13px 0}.choice{display:flex;text-align:left;align-items:center;gap:10px;min-height:43px;padding:10px 13px;border:1px solid var(--line);border-radius:11px;background:#fafbf6;color:var(--text);font-size:14px;line-height:1.45}.choice:before{content:'';border:1px solid #a1b497;border-radius:50%;width:16px;height:16px;flex-shrink:0;background:white}.choice.chosen{border-color:var(--green);background:var(--soft)}.choice.chosen:before{border:5px solid var(--green)}.feedback{font-size:13px;padding:10px 13px;border-radius:10px;margin-top:10px;background:var(--sand);color:#825124}.feedback.good{background:#deefcf;color:var(--green)}.hint-area{margin-top:12px;display:flex;gap:9px;flex-wrap:wrap;align-items:center}.hint-locked{font-size:11px;color:var(--muted)}.hint-text{margin-top:12px;border-left:3px solid #e8b85a;background:#fbf3de;border-radius:0 10px 10px 0;padding:12px;font-size:13px;white-space:pre-line}.complete{margin-top:16px;border:1px solid #bbd1ad;background:#eaf4e0;border-radius:17px;padding:20px}.complete h3{margin-bottom:8px}.complete p{font-size:13px;color:var(--muted);white-space:pre-line}.complete-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:15px}.notes{margin-top:18px}.notes summary{font-size:13px;color:var(--muted);cursor:pointer}.notes textarea{width:100%;min-height:120px;padding:12px;border:1px solid var(--line);border-radius:12px;background:#fffefb;resize:vertical;margin-top:10px;color:var(--text);font-size:14px}.bottom-actions{display:flex;justify-content:space-between;gap:10px;margin-top:20px}.text-btn{background:transparent;color:var(--green);font-size:12px;padding:8px 0}.storage-note{font-size:10px;color:var(--muted);margin-top:17px}.mobile-lessons{display:none;margin-bottom:14px}.mobile-lessons summary{font-size:13px;font-weight:bold;color:var(--green);padding:10px 0;cursor:pointer}.mobile-lessons select{width:100%;padding:10px;border:1px solid var(--line);border-radius:10px;background:var(--paper);font-size:13px;color:var(--text)}.assessment{max-width:800px;margin:25px auto}.assessment-head{display:flex;justify-content:space-between;gap:20px;align-items:start;margin-bottom:20px}.assessment h1{font-size:32px;letter-spacing:-1px}.assessment-head p{font-size:13px;color:var(--muted);margin-top:9px}.assessment-count{white-space:nowrap;color:var(--green);font-size:14px}.assessment .progress-track{margin-bottom:23px}.assessment .task-card{margin-bottom:15px}.result-hero{background:var(--ink);color:#fff;border-radius:24px;padding:30px;margin:20px 0}.result-hero h1{color:#fff;font-size:35px;letter-spacing:-1px}.result-hero p{font-size:14px;color:#d7e6cc;margin-top:10px}.result-score{font-size:46px;line-height:1.2;font-weight:bold;color:var(--lime);margin:15px 0}.result-list{display:flex;flex-direction:column;gap:10px}.result-item{background:var(--paper);padding:17px;border:1px solid var(--line);border-radius:15px}.result-item-head{display:flex;justify-content:space-between;gap:20px;align-items:start}.result-item h3{font-size:15px}.result-item p{font-size:12px;color:var(--muted);margin-top:5px}.result-item details{font-size:13px;margin-top:9px}.badge-ok,.badge-review{font-size:10px;font-weight:bold;text-transform:uppercase;white-space:nowrap;color:var(--green);background:var(--soft);padding:5px 8px;border-radius:7px}.badge-review{color:#975127;background:#f7e9d9}.empty{padding:35px;background:var(--paper);border-radius:20px;text-align:center}.empty p{color:var(--muted);font-size:14px;margin:12px 0}.prose{max-width:830px;margin:30px auto}.prose h1{font-size:35px;margin-bottom:20px}.prose h2{font-size:22px;margin:25px 0 12px}.prose p,.prose li{font-size:14px;line-height:1.7}.prose p{margin:10px 0}.prose a{overflow-wrap:anywhere}.notice{background:var(--sand);border-radius:12px;padding:14px;font-size:13px;color:#825124}.safety-save{display:none;margin:12px 0;padding:12px;border-radius:12px;background:var(--sand);font-size:12px;color:#825124}.safety-save.visible{display:block}.data-actions{display:flex;gap:10px;flex-wrap:wrap;margin:22px 0}.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.no-script{padding:30px;border:2px solid var(--orange);background:var(--paper);margin:25px;border-radius:20px}.report-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin:22px 0}.report-metric{background:var(--paper);border:1px solid var(--line);border-radius:17px;padding:20px}.report-metric b{display:block;font-size:30px;color:var(--green)}.report-metric small{font-size:12px;color:var(--muted)}.self-check{margin-top:14px;padding-top:12px;border-top:1px solid #c4d6b8;color:var(--muted);font-size:12px}.self-check label{display:flex;gap:10px;align-items:start}.self-check input{margin-top:3px;width:16px;height:16px;flex-shrink:0}.lesson-card:disabled{opacity:1}.inline-note{font-size:12px;color:var(--muted);margin:10px 0}.review-only{color:#9c6122}.print-only{display:none}@media(max-width:1050px){.shell{padding:0 22px}.hero{gap:28px}.hero-visual{height:225px}.work-grid{grid-template-columns:210px minmax(0,1fr);gap:18px}.side{padding:12px}.course-grid{gap:13px}.course{padding:19px}.meta-line{gap:21px}}@media(max-width:780px){.shell{padding:0 18px}.site-header{height:72px}.brand-name{font-size:18px}.nav button{padding:9px;font-size:12px}.hero{padding:34px 0 26px;grid-template-columns:1.2fr .8fr;gap:20px}.hero h1{font-size:38px;letter-spacing:-1px}.hero-visual{height:210px}.hero p{font-size:14px}.meta-line{gap:20px}.meta-line strong{font-size:23px}.course-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.work-grid{display:block}.side{display:none}.mobile-lessons{display:block}.route-head{padding:25px;gap:20px}.lesson-heading h1{font-size:27px}.task-card{padding:21px}.footer{margin-top:28px}}@media(max-width:520px){.shell{padding:0 14px}.site-header{gap:8px;height:66px}.brand-mark{width:34px;height:34px;font-size:21px;border-radius:10px}.brand{gap:8px}.brand-name{font-size:17px}.brand-sub{font-size:9px;letter-spacing:1px}.nav{gap:3px}.nav button{font-size:11px;padding:8px 6px}.nav button:nth-child(2){display:none}.hero{display:block;padding:28px 0 22px}.hero h1{font-size:38px;margin:14px 0}.hero p{font-size:14px;max-width:350px}.hero-visual{display:none}.meta-line{gap:24px;margin-top:20px}.meta-line strong{font-size:24px}.section-title{align-items:start;flex-direction:column;gap:6px;margin:17px 0}.section-title h2{font-size:22px}.section-title p{font-size:12px}.course-grid{grid-template-columns:1fr;gap:12px}.course{padding:19px;min-height:0}.course-top{margin-bottom:10px}.course p{margin-bottom:12px}.course .btn{margin-top:12px}.grade-badge{width:52px;height:52px;font-size:29px}.course h3{font-size:20px}.info-strip{padding:17px;display:block}.info-strip p{font-size:12px}.footer{font-size:10px;display:block;padding:19px 0}.footer div+div{margin-top:8px}.route-head{padding:22px;display:block}.route-head h1{font-size:29px}.route-stats{margin-top:18px;min-width:0;text-align:left;display:flex;gap:10px;align-items:center}.route-stats b{font-size:27px}.route-stats .progress-track{width:100px;margin:0 0 0 auto}.route-head p{font-size:13px}.lesson-grid{grid-template-columns:1fr}.lesson-card{padding:14px;gap:12px}.lesson-card h3{font-size:15px}.lesson-heading h1{font-size:25px;line-height:1.15}.lesson-heading p{font-size:12px}.crumb{font-size:11px;margin:15px 0 11px;gap:6px}.crumb button{font-size:11px}.mobile-lessons{margin-bottom:9px}.theory{margin:12px 0}.theory summary{font-size:12px;padding:11px 13px}.theory-inside{padding:0 13px 13px;font-size:13px}.toolbar{gap:9px;margin:12px 0}.segmented button{padding:7px 9px;font-size:11px}.task-tab{width:30px;height:31px;font-size:12px;border-radius:8px}.task-tabs{gap:4px}.task-card{padding:17px;border-radius:17px}.task-top{margin-bottom:10px}.task-prompt{font-size:16px;line-height:1.55}.diagram{margin-top:12px}.diagram svg{max-height:200px}.step{padding:15px;border-radius:14px}.step h3{font-size:15px}.step.done{padding:12px 14px}.answer-input{width:100%;font-size:17px}.answer-form .btn{width:100%}.choice{font-size:13px;padding:10px;gap:8px}.complete{padding:16px}.complete-actions .btn{width:100%}.mode-note{font-size:10px;margin:10px 0}.bottom-actions{flex-wrap:wrap}.assessment{margin:20px 0}.assessment h1{font-size:27px}.assessment-head{gap:15px}.assessment-count{font-size:11px}.assessment .btn{font-size:12px}.result-hero{padding:23px}.result-hero h1{font-size:28px}.result-item-head{gap:10px}.report-grid{gap:8px}.report-metric{padding:12px}.report-metric b{font-size:24px}.report-metric small{font-size:10px}.prose h1{font-size:29px}.route-actions .btn{font-size:12px;padding:10px 13px}.btn{min-height:44px}.assessment-head p{font-size:12px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}@media print{body{background:white;color:black;font-size:12pt}.shell{max-width:none;padding:0}.site-header,.footer,.nav,.side,.mobile-lessons,.toolbar,.notes,.hint-area,.bottom-actions,.btn,.data-actions{display:none!important}.work-grid{display:block}.task-card,.step,.result-item{break-inside:avoid;box-shadow:none}.task-card{margin-bottom:12pt}.theory{display:none}.report-metric{padding:8px}.print-only{display:block}.course-grid{grid-template-columns:1fr 1fr}.result-list{display:block}.result-item{margin-bottom:10px}}
.plot-lab{margin:12px 0;padding:13px 15px;border:1px solid var(--line);border-radius:15px;background:var(--paper)}.plot-lab summary{font-size:13px;color:var(--green);font-weight:bold;cursor:pointer}.plot-lab p{font-size:12px;margin-top:10px}.plot-lab svg{display:block;max-width:480px;width:100%;margin:5px auto;cursor:crosshair;touch-action:none}.plot-inputs{display:flex;align-items:end;gap:8px;flex-wrap:wrap;margin-top:12px}.plot-inputs label{font-size:11px;display:flex;flex-direction:column;gap:3px;color:var(--muted)}.plot-inputs input{width:62px;height:38px;border:1px solid var(--line);border-radius:8px;padding:6px;background:white}.plot-message{background:var(--soft);padding:10px;border-radius:9px;color:var(--muted)}.plot-message.ok{background:#dcefcf;color:var(--green)}
/* Website entry and the existing shared-board host. */
[hidden]{display:none!important}.brand{text-decoration:none}.nav{flex-wrap:wrap;justify-content:flex-end}.nav a{font-size:13px;color:var(--green);padding:8px;text-decoration:none;border-radius:9px}.nav a:hover{background:var(--soft)}.site-header{height:auto;min-height:82px;padding-block:12px}.entry-actions{display:flex;align-items:center;justify-content:flex-end;gap:12px;flex-wrap:wrap;margin:8px 0;font-size:12px;color:var(--muted)}.board-note{display:none}.board-mode .site-header,.board-mode .entry-actions,.board-mode .footer,.board-mode .safety-save,.board-mode [data-action="diagnostic"],.board-mode [data-action="errors"],.board-mode [data-action="progress"],.board-mode .route-stats,.board-mode .self-check{display:none!important}.board-mode .shell{max-width:none;padding:10px 14px}.board-mode .board-note{display:block;margin:0 0 8px;font-size:12px;color:var(--muted)}.board-mode main{min-height:0}.board-mode .crumb{margin-top:8px}.board-mode .side{max-height:80vh}.board-mode .hero{padding-block:12px}.board-mode .hero-visual{display:none}.board-mode .hero{grid-template-columns:1fr}.board-mode .lesson-heading p{display:none}.board-mode .storage-note{font-size:12px}
@media(max-width:520px){.site-header{align-items:flex-start;min-height:0;padding-block:12px;flex-direction:column;gap:8px}.nav{width:100%;justify-content:space-between;gap:0}.nav a,.nav button{padding:8px 5px;font-size:11px}.entry-actions{margin:5px 0;gap:5px;justify-content:flex-start}.entry-actions span{font-size:10px}.lesson-heading p{display:none}.crumb{margin-block:10px}.task-prompt{overflow-wrap:anywhere}.diagram svg{max-height:180px}.lesson-heading h1{font-size:24px}.board-mode .shell{padding:8px 10px}}