:root{--activity-accent:#176d75;--activity-ink:#163952;--activity-surface:#f2faf9}.activity-mission{height:100%;min-height:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2vh;background:var(--activity-surface);border-radius:24px;padding:2vh 3vw;box-sizing:border-box;color:var(--activity-ink)}.activity-eyebrow{font-size:clamp(14px,2vh,24px);font-weight:750;letter-spacing:.08em;margin:0}.activity-stimulus{flex:1;min-height:0;display:flex;align-items:center;justify-content:center;width:100%;background:white;border:3px solid var(--activity-accent);border-radius:22px;padding:2vh;box-sizing:border-box;text-align:center}.activity-stimulus strong{font-size:clamp(32px,5.5vw,88px);overflow-wrap:anywhere;line-height:1.25}.activity-track{position:relative;width:90%;height:60px;flex-shrink:0}.activity-path{position:absolute;inset:25px 0;border-radius:20px;background:#bfded7}.activity-piece{position:absolute;top:0;transform:translateX(-50%);font-size:52px;color:#176d75;transition:left .22s ease-out}.activity-progress,.activity-feedback{font-size:clamp(16px,2.5vh,28px);margin:0;text-align:center}.activity-feedback{min-height:1.4em;font-weight:700}.activity-character{font-size:clamp(44px,8vh,96px);color:var(--activity-accent)}.activity-complete h1{font-size:clamp(30px,5vw,72px);text-align:center}.lab-stage:has(.activity-mission){display:block}.lab-project .activity-mission{height:100%}.lab-session:has(.activity-mission) .lab-card-window{display:none}@media(prefers-reduced-motion:reduce){.activity-piece{transition:none}}@media(max-height:700px){.activity-mission{gap:8px}.activity-track{height:42px}.activity-piece{font-size:40px}.activity-stimulus strong{font-size:clamp(28px,4vw,60px)}}

.activity-reference{display:flex;align-items:center;justify-content:center;gap:14px;color:var(--activity-ink);background:var(--activity-surface);border-radius:18px;padding:8px 18px;flex-shrink:0}.activity-reference .activity-character{font-size:38px}.activity-reference strong{font-size:clamp(20px,2.4vw,36px)}.activity-reference>span:last-child{font-size:clamp(14px,1.5vw,22px)}.lab-stage:has(.activity-reference) .lab-card-window{min-height:0}.lab-project .lab-stage:has(.activity-reference) .lab-card-window{flex:1;display:flex;align-items:center}.lab-project .lab-stage:has(.activity-reference) .lab-card-track{width:100%}@media(max-width:600px){.activity-reference{flex-wrap:wrap;gap:6px}.activity-reference>span:last-child{display:none}}

/* Visual 2: incremental teacher shell only. Existing learning modules keep their layouts. */
.teacher-home{--teacher-brand:#19586c;--teacher-line:#d4e1e6;background:#f6f9fb;border-radius:24px}.teacher-heading{border-bottom:1px solid var(--teacher-line);padding-bottom:22px}.teacher-heading h1{letter-spacing:-.035em;color:#183c50}.teacher-quick{grid-template-columns:repeat(4,minmax(0,1fr))}.teacher-shortcut{border-radius:18px;border-top:4px solid var(--teacher-brand);padding:22px 18px;transition:background .15s,border-color .15s}.teacher-shortcut strong{font-size:19px}.teacher-home .panel{border:1px solid var(--teacher-line);box-shadow:0 4px 18px #18395807;border-radius:18px}.teacher-resume{border-left:5px solid var(--teacher-brand)!important;background:#edf7f7}.teacher-admin{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.teacher-nav-group{display:flex;flex-direction:column;align-items:stretch;gap:8px;padding:16px;border:1px solid var(--teacher-line);background:white;border-radius:16px}.teacher-nav-group h2{font-size:17px;margin:0 0 8px}.teacher-nav-group button{text-align:left}.teacher-home button,.lab-home button,.lab-session button{min-height:40px;touch-action:manipulation}.teacher-home button:focus-visible,.lab-home :is(button,input,select,summary):focus-visible,.lab-session :is(button,select):focus-visible{outline:3px solid #08758a;outline-offset:3px}.teacher-home button:disabled,.lab-home button:disabled{opacity:.5;cursor:wait}.teacher-home .primary,.lab-home .primary{background:#19586c;border-color:#19586c;color:white}.teacher-home .plain,.lab-home .plain{color:#173f52;background:#f5f9fa;border-color:#b7ccd5}.lab-home{color:#163952}.lab-home>header{border-bottom:1px solid #ccdee4;margin-bottom:22px}.lab-home h1{letter-spacing:-.025em}.lab-home fieldset{background:#fff;border-color:#ccdee4;box-shadow:0 3px 14px #12395005;border-radius:16px}.lab-home legend{font-size:15px;letter-spacing:.025em}.lab-home #lab-setup-summary{background:#edf7f7;border-left:4px solid #176d75;padding:14px;border-radius:8px;font-weight:650}.lab-home details.panel{border:1px solid #ccdee4;border-radius:16px;background:#fff}.lab-session{background:#f3f8fa}.lab-session>header{border-bottom:1px solid #cfdee4;padding-bottom:8px}.lab-controls{border:1px solid #c7dae1;box-shadow:0 4px 16px #1239500a;border-radius:16px}.lab-controls [data-lab=answer][data-result=ACERTO],.lab-session [data-lab=project]{background:#19586c;color:white;border-color:#19586c}.lab-controls [data-lab=answer][data-result=ERRO]{background:#fff5dc;color:#64480c;border-color:#c4ac73}.lab-controls [data-lab=finish]{background:#fff2ef;color:#862f27;border-color:#d9a59e}.lab-controls [data-lab=answer][data-result=PULAR]{background:#edf2f6;color:#25445b}.lab-session [role=alert],.lab-home [role=alert]{padding:10px;border-left:4px solid #a34032;background:#fff3f0;color:#752f27}.activity-teacher-pause,.lab-pause-badge{background:#fff4cf;border:1px solid #c7ac55;border-radius:12px;padding:8px;text-align:center;font-weight:750;color:#574213;margin:0}.lab-replace-dialog{border:1px solid #afc8d3;border-radius:18px;padding:24px;max-width:480px;box-shadow:0 16px 60px #14354a33}.lab-replace-dialog::backdrop{background:#12364c66}.lab-replace-dialog button{margin:6px;padding:10px;border-radius:9px;border:1px solid #a7bdca;background:#f2f7fa;color:#163952}.lab-replace-dialog [data-choice=replace]{background:#fff0ec;color:#862f27}.lab-summary{border:1px solid #bdd8db;border-top:5px solid #176d75;background:#fff;border-radius:20px}.lab-summary h2{color:#175460}.lab-controls button:active,.teacher-home button:active{transform:translateY(1px)}
@media(max-width:1050px){.teacher-quick{grid-template-columns:repeat(2,minmax(0,1fr))}.teacher-admin{grid-template-columns:1fr}}@media(max-width:700px){.teacher-quick{grid-template-columns:1fr}.teacher-home{border-radius:12px}.teacher-nav-group{padding:12px}.lab-controls button{min-height:36px}.lab-session>header{gap:6px}}@media(prefers-reduced-motion:reduce){.teacher-shortcut{transition:none}.lab-controls button:active,.teacher-home button:active{transform:none}}

.activity-piece.activity-progressed{animation:activity-step .22s ease-out}@keyframes activity-step{from{transform:translateX(calc(-50% - 18px)) scale(.95)}to{transform:translateX(-50%) scale(1)}}@media(prefers-reduced-motion:reduce){.activity-piece.activity-progressed{animation:none}}

.activity-track{height:100px;margin:12px 0}.activity-path{inset:38px 0 18px;background:repeating-linear-gradient(90deg,#2a6975 0 70px,#2a6975 70px 78px,#c9d9dd 78px 86px);border:5px solid #759da7;border-radius:28px;box-shadow:inset 0 0 0 3px #fff}.activity-piece{top:28px;font-size:50px;color:#ffcf3a;text-shadow:0 2px 2px #173952;z-index:1}.activity-start,.activity-finish{position:absolute;top:0;font:800 17px system-ui;color:#173952}.activity-start{left:0}.activity-finish{right:0}.activity-stimulus{min-height:100px}.lab-built>div{border-top:8px solid #176d75;background:#fff}.lab-built>div strong{display:block}.activity-reference{border-left:6px solid #176d75}.activity-reference .activity-character{font-size:52px}@media(max-height:700px){.activity-track{height:72px;margin:4px}.activity-path{inset:30px 0 10px}.activity-piece{top:18px;font-size:42px}.activity-start,.activity-finish{font-size:14px}}