:root{font-family:'Plus Jakarta Sans','Segoe UI',sans-serif;color:#1d2c42;background:#f5f7fb;font-synthesis:none;text-rendering:optimizeLegibility}*{box-sizing:border-box}body{margin:0;min-width:320px}button,input{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.56}button:focus-visible,input:focus-visible{outline:3px solid #94b3ff;outline-offset:3px}.app-shell{display:flex;min-height:100vh}.sidebar{background:#101d36;color:#dbe7ff;width:284px;min-width:284px;display:flex;flex-direction:column;padding:28px 18px 24px;position:sticky;top:0;height:100vh;overflow:auto}.brand{display:flex;align-items:center;gap:12px;padding:0 10px}.brand-mark{font-size:30px;font-weight:800;background:#526ff8;color:#fff;width:43px;height:43px;border-radius:13px;display:grid;place-items:center;line-height:1}.brand strong{color:#fff;display:block;font-size:24px;letter-spacing:-1.2px}.brand-star{color:#6d90ff}.brand small{display:block;font-size:8px;font-weight:800;letter-spacing:1.24px;color:#7e90b2;margin-top:3px}.sidebar-intro{padding:52px 12px 33px}.eyebrow{color:#9fafff;letter-spacing:1.7px;font-size:10px;font-weight:800}.eyebrow.dark{color:#7385dc}.sidebar-intro h2{color:#fff;font-size:29px;line-height:1.24;letter-spacing:-1.2px;margin:16px 0}.sidebar-intro h2 em{font-style:normal;color:#83a0ff}.sidebar-intro p{font-size:12px;line-height:1.8;color:#91a2be;max-width:230px;margin:0}.sidebar-section{display:flex;justify-content:space-between;font-size:10px;font-weight:800;letter-spacing:1.2px;color:#7890b3;padding:9px 10px 15px}.sidebar-section span{font-weight:500;letter-spacing:0}.lesson-nav{display:grid;gap:5px}.lesson-item{border:1px solid transparent;background:transparent;color:#adbed6;text-align:left;display:flex;align-items:center;gap:12px;border-radius:12px;padding:11px 10px;min-height:64px;width:100%;transition:background .15s}.lesson-item:hover{background:#192b4b}.lesson-item.selected{background:#283b65;border-color:#3b5389;color:#fff}.lesson-glyph{flex:0 0 40px;height:40px;display:grid;place-items:center;background:#263552;border-radius:10px;font-weight:800;font-size:23px}.lesson-item strong{display:block;color:inherit;font-size:12px;font-weight:750}.lesson-item small{display:block;color:#8194b4;font-size:10px;margin-top:5px}.lesson-number{margin-left:auto;font-size:10px;color:#6b7d9b}.lesson-item.selected .lesson-number{color:#a4c5ff}.sidebar-footer{margin-top:auto;padding-top:20px}.nav-analysis{color:#aebddb;border:none;background:transparent;padding:16px 14px;width:100%;text-align:left;font-size:12px;font-weight:700;border-radius:10px}.nav-analysis:hover,.nav-analysis.active{background:#293c60;color:#fff}.nav-analysis span{margin-right:12px;font-size:17px}.privacy-note{display:flex;gap:12px;background:#192c43;border:1px solid #2b4658;border-radius:14px;padding:14px 12px;margin-top:20px;align-items:center}.privacy-note>span{color:#63dfae;font-size:20px}.privacy-note strong{display:block;color:#bde7d6;font-size:10px}.privacy-note small{display:block;margin-top:5px;font-size:9px;color:#8fa6b8}.main-panel{min-width:0;flex:1}.topbar{height:75px;background:#fff;border-bottom:1px solid #e6ebf2;display:flex;align-items:center;justify-content:space-between;padding:0 clamp(22px,4.2vw,68px)}.crumb{font-size:10px;letter-spacing:1.25px;font-weight:800;color:#6f83a4}.crumb span{padding:0 12px;color:#d0d8e5}.topright{display:flex;align-items:center;gap:20px}.free-pill{display:inline-flex;align-items:center;gap:8px;background:#e5f8ef;color:#1d996a;border-radius:24px;padding:9px 13px;font-size:10px;letter-spacing:1px;font-weight:800}.free-pill i,.live-dot{display:inline-block;background:#2abe85;width:7px;height:7px;border-radius:50%;margin-right:4px}.avatar{display:grid;place-items:center;width:32px;height:32px;border-radius:50%;background:#e5e9ff;color:#526dcc;font-size:13px;font-weight:800}.content{max-width:1600px;margin:0 auto;padding:clamp(25px,3.4vw,52px) clamp(20px,4.2vw,68px) 26px}.welcome{display:flex;align-items:center;justify-content:space-between;margin-bottom:30px}.welcome h1{font-size:clamp(28px,3.3vw,46px);line-height:1.14;letter-spacing:-1.9px;color:#192a44;margin:11px 0}.small-star{color:#758bfa;font-size:17px;vertical-align:top;display:inline-block;margin-left:12px}.welcome p{font-size:13px;color:#8592a6;margin:0}.lesson-badge{display:grid;place-items:center;width:69px;height:69px;border-radius:20px;background:#fff;font-size:36px;box-shadow:0 8px 28px #1726470a}.quick-stats{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px;margin-bottom:27px}.stat{background:#fff;border:1px solid #e7edf6;border-radius:15px;padding:19px 23px;min-height:104px}.stat>span{display:block;font-size:10px;letter-spacing:1px;color:#97a3b6;font-weight:800;margin-bottom:12px}.stat strong{font-family:'DM Sans','Segoe UI',sans-serif;font-weight:800;color:#26375b;font-size:26px;letter-spacing:-1px}.stat small{font-size:12px;color:#a6b3c6;margin-left:5px;font-weight:700}.stat-tint{background:#e8efff;border-color:#dce5ff}.stat-tint strong{font-size:17px;color:#5369dc;white-space:nowrap}.shield{margin-left:6px;color:#7795d3}.body-grid{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(330px,1fr);gap:23px;align-items:start}.left-content,.right-content{min-width:0;display:grid;gap:18px}.plot-card{background:#101d35;border-radius:18px;overflow:hidden;box-shadow:0 16px 35px #21375a14}.plot-toolbar{display:flex;align-items:center;justify-content:space-between;min-height:58px;padding:0 24px;color:#d7e1fc;font-weight:800;font-size:10px;letter-spacing:1.1px;gap:8px}.plot-sub{font-weight:500;text-transform:none;color:#7f93b6;letter-spacing:0}.mini-button{background:#283a59;border:1px solid #3a5074;padding:9px 12px;border-radius:8px;color:#d0ddf6;font-size:11px;font-weight:700;white-space:nowrap}.mini-button:hover{background:#3c5180}.plot-frame{width:100%;aspect-ratio:760/430;overflow:hidden}.plot-svg{display:block;width:100%;height:100%}.geo-host{width:100%;height:100%;min-height:280px;overflow:hidden}.plot-bottom{padding:15px 23px;display:flex;align-items:center;justify-content:space-between;border-top:1px solid #263855;gap:15px;color:#7a92b7;font-size:10px}.zoom-label{display:flex;gap:10px;align-items:center;white-space:nowrap}.zoom-label input{max-width:110px;accent-color:#9fb7ff;cursor:pointer}.plot-error{padding:12px 22px;background:#532a3d;color:#fff;font-size:12px}.theory-card{background:#fff;border-radius:16px;padding:24px;display:flex;gap:15px;border:1px solid #e8edf5}.theory-icon{flex:0 0 39px;height:39px;background:#edf0ff;border-radius:12px;display:grid;place-items:center;color:#7e89f7;font-size:23px}.theory-card h3{font-size:14px;margin:1px 0 9px;color:#344766}.theory-card p{line-height:1.85;color:#8190a3;font-size:12px;margin:0}.exercise-card{background:#fff;border:1px solid #e7edf6;border-radius:18px;padding:26px}.exercise-head{display:flex;align-items:start;justify-content:space-between;margin-bottom:22px}.exercise-head h2{color:#223450;font-size:22px;letter-spacing:-.5px;margin:9px 0 0}.exercise-head h2 span{color:#637de9}.exercise-head h2 small{font-size:12px;color:#a1acc2}.task-icon{font-size:25px;background:#edf2ff;border-radius:12px;width:39px;height:39px;display:grid;place-items:center;color:#7384dc}.question-box{background:#f5f7fd;border:1px solid #ecf0fa;border-radius:12px;padding:20px;margin-bottom:24px}.question-label{font-size:10px;font-weight:800;color:#8998b2;letter-spacing:1.1px}.question-formula{font-family:'Cambria Math',Georgia,serif;color:#263d70;font-size:clamp(16px,1.65vw,23px);font-weight:700;margin:16px 0;line-height:1.5;overflow-wrap:anywhere}.question-box p{font-size:12px;color:#5e6e85;line-height:1.65;margin:0}.answer-label{display:block;font-weight:800;font-size:12px;color:#344966;margin-bottom:12px}.input-wrap{display:flex;align-items:center;border:1.5px solid #dae2f0;border-radius:10px;padding:0 12px;background:#fff}.input-wrap:focus-within{border-color:#8297fc}.input-wrap input{height:50px;border:0;outline:none;background:transparent;width:100%;min-width:0;font-size:14px}.input-wrap>span{color:#b7c5d7;font-size:18px}.field-foot{font-size:10px;color:#a2aec0;margin:10px 0 20px}.primary-button{display:flex;align-items:center;justify-content:center;gap:12px;background:#5975ee;color:white;border:0;border-radius:10px;min-height:48px;padding:13px 17px;font-size:12px;font-weight:800;width:100%;box-shadow:0 8px 20px #5975ee24}.primary-button:hover:not(:disabled){background:#4a63dd}.primary-button span{font-size:18px}.practice-footer{display:flex;justify-content:space-between;align-items:center;margin-top:20px;border-top:1px solid #edf1f7;padding-top:20px}.practice-footer span{font-size:11px;color:#a0acbe}.link-button,.back-button{color:#5873e8;border:none;background:transparent;padding:0;font-size:11px;font-weight:800}.link-button:hover,.back-button:hover{text-decoration:underline}.verdict{margin-top:17px;padding:15px;border-radius:10px;font-size:12px;line-height:1.7}.verdict p{margin:7px 0 0}.verdict.correct{color:#18745b;background:#e6f7ef}.verdict.incorrect{color:#986022;background:#fff1dd}.verdict.invalid{color:#9b3e3e;background:#fff0f0}.tutor-card{background:#ebedff;border:1px solid #e3e6ff;border-radius:16px;padding:23px}.tutor-top{display:flex;gap:12px;align-items:center}.tutor-logo{width:40px;height:40px;border-radius:12px;background:#6378e6;color:white;font-size:23px;display:grid;place-items:center}.tutor-top h3{font-size:13px;color:#4353a6;margin:0 0 5px}.tutor-top p{font-size:10px;color:#8591c5;margin:0}.tutor-copy{font-size:12px;line-height:1.8;color:#707fb0;margin:16px 0}.mode-switch{display:flex;gap:5px;background:#dde2fa;padding:5px;border-radius:10px;margin-top:16px}.mode-switch button{flex:1;background:transparent;border:0;border-radius:7px;color:#6d7dae;font-size:11px;font-weight:800;padding:9px}.mode-switch button.active{background:#fff;color:#5267d5;box-shadow:0 2px 6px #1b24701c}.hint-button{width:100%;border:1px solid #c7d0fc;background:#f9faff;border-radius:9px;min-height:42px;font-size:12px;font-weight:800;color:#6073c9}.hint-button:hover:not(:disabled){background:#fff}.hint-message{background:#fff;border-radius:10px;padding:15px;margin-bottom:14px;color:#5367ab}.hint-message span{font-size:9px;font-weight:800;letter-spacing:1px}.hint-message p{font-size:12px;line-height:1.7;margin:7px 0 0}.main-footer{color:#a3afbe;font-size:10px;margin-top:29px;text-align:center}.analysis-page{max-width:1180px}.analysis-card{background:#fff;border:1px solid #e6eaf4;border-radius:16px;padding:29px;margin-bottom:18px}.analysis-card h2{font-size:20px;color:#273653;margin:0 0 8px}.analysis-card p{font-size:12px;color:#7c8aa1;line-height:1.8;margin:0 0 22px}.analytics-bars{display:grid;gap:18px}.bar-row{display:grid;grid-template-columns:minmax(125px,185px) 1fr 55px;gap:16px;align-items:center;font-size:12px;color:#59708d}.bar-row>span{font-weight:800;color:#5267a5;text-align:right}.bar-track{background:#eff2fc;height:13px;border-radius:12px;overflow:hidden}.bar-fill{height:100%;background:#8498f6;border-radius:12px;min-width:0}.empty-report{text-align:center;padding:28px;color:#9aaac0;font-size:12px}.export-actions{display:flex;gap:13px;flex-wrap:wrap}.export-actions button{width:auto;min-width:150px}.outline-button,.danger-button{border:1px solid #d9e2ef;background:white;border-radius:10px;padding:12px 17px;font-size:12px;font-weight:750;color:#526988}.danger-button{color:#b04f57}.fineprint{display:block;color:#99a6b5;font-size:10px;margin-top:18px;line-height:1.7}.back-button{margin-top:12px}@media(max-width:1150px){.sidebar{width:244px;min-width:244px}.body-grid{grid-template-columns:1fr}.quick-stats{gap:10px}.stat{padding:15px}.content{padding:30px}.topbar{padding:0 30px}}@media(max-width:740px){.app-shell{display:block}.sidebar{position:static;height:auto;width:auto;min-width:0;padding:15px}.brand{padding:0}.sidebar-intro{display:none}.sidebar-section{padding-top:18px}.lesson-nav{grid-template-columns:repeat(3,minmax(0,1fr))}.lesson-item{padding:8px;display:block;text-align:center}.lesson-glyph{width:34px;height:34px;margin:0 auto 8px}.lesson-item strong{font-size:10px}.lesson-item small,.lesson-number{display:none}.sidebar-footer{margin:0;padding:6px 0 0}.nav-analysis{padding:11px}.privacy-note{display:none}.topbar{height:58px;padding:0 17px}.content{padding:25px 16px}.welcome{margin-bottom:22px}.welcome h1{font-size:29px}.lesson-badge{width:55px;height:55px;font-size:27px}.quick-stats{grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.stat{min-height:85px}.stat strong{font-size:22px}.exercise-card{padding:19px}.plot-toolbar{padding:0 12px}.plot-bottom{padding:12px;flex-wrap:wrap}.bar-row{grid-template-columns:100px 1fr 37px;gap:8px;font-size:10px}.export-actions button{width:100%}.analysis-card{padding:18px}}@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}

.explore-controls{padding:16px 23px 20px;border-top:1px solid #263855;background:#15223d}.explore-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;color:#c3d0ec;font-size:10px;letter-spacing:.9px;font-weight:800}.explore-heading small{color:#7589ab;font-size:9px;letter-spacing:0;font-weight:500}.explore-heading button{border:0;background:transparent;color:#8faaf2;font-size:10px;font-weight:750}.slider-row{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px;margin-top:16px}.parameter{display:grid;gap:7px;color:#9cb0d4;font-size:11px}.parameter>span{display:flex;justify-content:space-between}.parameter b{color:#cbdafa}.parameter input{width:100%;accent-color:#849bff}@media(max-width:740px){.explore-controls{padding:14px}.slider-row{grid-template-columns:repeat(2,minmax(0,1fr))}.explore-heading{flex-wrap:wrap}}

.local-ai-button{margin-top:9px;width:100%;padding:11px 8px;border:1px solid #bcc8f8;border-radius:9px;background:transparent;color:#6373b4;font-size:10px;font-weight:800}.local-ai-button:hover{background:#fff}.ai-error{margin:12px 0 0;color:#a25c5c;font-size:11px;line-height:1.7}

/* Production: explicit privacy controls, accessible focus, readable errors. */
.consent-banner{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:16px 24px;background:#ebf3ff;border-bottom:1px solid #c8d9fb;color:#243252}
.consent-banner strong{display:block;font-size:13px;margin-bottom:5px}
.consent-banner p{font-size:11px;line-height:1.6;max-width:760px;margin:0;color:#526581}
.consent-actions{display:flex;flex-wrap:wrap;gap:9px;flex-shrink:0}
.consent-actions button,.tracking-status button{border:1px solid #c4d1e5;border-radius:9px;background:#fff;color:#2e4f91;font-weight:750;cursor:pointer;padding:10px 13px;font-size:11px}
.consent-actions button:first-child{color:white;border-color:#4468d4;background:#4468d4}
.tracking-status{padding:14px 0 18px;font-size:12px;line-height:1.5;color:#435370}
.tracking-status button{margin-left:12px;padding:7px 9px}
.ai-disclosure{margin-top:9px;color:#68768d;font-size:10px;line-height:1.65}
button:focus-visible,input:focus-visible,a:focus-visible{outline:3px solid #63cda9!important;outline-offset:3px}
button:disabled{cursor:not-allowed;opacity:.62}
@media(max-width:840px){.consent-banner{flex-direction:column;align-items:flex-start;padding:14px 16px}.consent-actions{width:100%}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}

.storage-warning{background:#fff1e4;color:#8e4b23;padding:13px 24px;font-size:12px;border-bottom:1px solid #f4c397}

.study-arm{font-size:11px;padding:8px 12px;border-radius:8px;background:#eef1fc;color:#596eaf;margin:8px 0}

/* MathLab 1.2 — teaching-first design foundation. Override prototype dashboard shell. */
:root{--ink:#142744;--secondary:#425570;--muted:#53627b;--primary:#345de1;--surface:#fff;--canvas:#f2f5fb;--line:#dce4ef;background:var(--canvas);color:var(--ink)}
body{background:var(--canvas);font-size:16px;line-height:1.5}
.app-shell{background:var(--canvas)}
.main-panel{background:var(--canvas)}
.sidebar{background:#12233e}
.brand small{font-size:10px;color:#b4c3df;letter-spacing:.08em}
.sidebar-section,.sidebar-intro p,.lesson-item small,.lesson-number{color:#b7c6df}
.sidebar-intro{padding-top:36px;padding-bottom:23px}
.sidebar-intro h2{font-size:26px}
.sidebar-intro p{font-size:14px;line-height:1.6}
.lesson-item strong,.nav-analysis{font-size:14px}
.lesson-item small{font-size:12px}
.topbar{height:62px}
.crumb{font-size:12px;color:#52647e;letter-spacing:.04em}
.free-pill,.avatar{display:none}
.content{padding-top:24px}
.welcome{margin-bottom:14px}
.welcome h1{font-size:clamp(28px,3vw,40px);letter-spacing:-.035em;margin:6px 0}
.welcome p{color:var(--secondary);font-size:15px;line-height:1.6;max-width:640px}
.eyebrow,.eyebrow.dark{font-size:12px;letter-spacing:.08em;color:#435dc0}
.learning-path{display:flex;align-items:center;gap:10px;margin:0 0 24px;flex-wrap:wrap}
.learning-path .phase{display:inline-flex;align-items:center;gap:8px;background:#fff;border:1px solid #dce4f0;border-radius:999px;color:#52627a;font-size:13px;padding:7px 12px;font-variant-numeric:tabular-nums}
.learning-path .phase.current{background:#e7edff;border-color:#b9c9f8;color:#244cb1}
.learning-path .path-progress{margin-left:auto;color:#405473;font-size:13px}
.body-grid{gap:22px}
.exercise-card{border-color:#dfe6f0;box-shadow:0 14px 30px #182c470a}
.exercise-head{margin-bottom:14px}
.exercise-head h2{font-size:22px}
.exercise-head h2 small{font-size:14px;color:#53627a}
.task-icon,.lesson-badge{opacity:.85}
.question-box{padding:17px 20px;margin-bottom:16px;background:#f3f6fd;border-color:#e0e7f5}
.question-label{color:#44597d;font-size:12px;letter-spacing:.06em}
.question-formula{font-size:clamp(20px,1.7vw,25px);margin:10px 0;line-height:1.4}
.question-box p{color:#314766;font-size:16px;line-height:1.5}
.answer-label{font-size:14px;margin-bottom:8px}
.input-wrap input{font-size:16px;min-height:50px}
.field-foot{color:#4a5d75;font-size:13px;line-height:1.45;margin:9px 0 15px}
.primary-button{font-size:15px;min-height:50px;background:#345de1}
.primary-button:hover:not(:disabled){background:#254abf}
.practice-footer{margin-top:14px;padding-top:12px}
.practice-footer span{font-size:13px;color:#435570}
.link-button,.back-button{font-size:14px;min-height:44px;padding:8px 10px}
.verdict,.verdict p{font-size:15px;line-height:1.55}
.tutor-card{background:#edf1ff;border-color:#d7e1ff}
.tutor-top h3{font-size:17px;color:#273c87}
.tutor-top p,.tutor-copy,.hint-message p{font-size:14px;color:#384c78;line-height:1.55}
.mode-switch button,.hint-button{font-size:14px;min-height:44px}
.ai-disclosure,.ai-error{font-size:13px;color:#435474}
.hint-message span{font-size:12px}
.plot-toolbar{font-size:13px;letter-spacing:.02em}
.mini-button{min-height:42px;font-size:13px}
.plot-bottom{font-size:13px;line-height:1.4;color:#c7d7f1;gap:12px}
.zoom-label{font-size:13px}
.explore-heading{font-size:13px;letter-spacing:.02em}
.explore-heading small{font-size:12px;color:#b6c7e2}
.explore-heading button{font-size:13px;min-height:44px;padding:6px 8px}
.parameter{font-size:14px;color:#d0ddf1}
.parameter input,.zoom-label input{min-height:34px;cursor:pointer}
.theory-card h3{font-size:16px}
.theory-card p{font-size:14px;color:#425470;line-height:1.6}
.consent-banner{padding:12px 22px;gap:14px}
.consent-banner strong{font-size:14px}
.consent-banner p{font-size:13px;color:#344a69}
.consent-actions button{min-height:44px;font-size:13px}
.analysis-card p,.analysis-card .bar-row{font-size:14px;color:#3d526c}
.fineprint{font-size:13px;color:#4b6079}
.main-footer{color:#54657d;font-size:12px}
@media (max-width:1150px){.body-grid{grid-template-columns:minmax(0,1.1fr) minmax(315px,1fr)}}
@media (max-width:900px){.body-grid{grid-template-columns:1fr}.left-content{order:2}.right-content{order:1}}
@media (max-width:740px){
 .sidebar{position:static;width:100%;height:auto;min-width:0;min-height:0;padding:12px 16px;display:flex;flex-direction:row;flex-wrap:wrap;align-items:center;gap:8px 12px;overflow:hidden}
 .brand{flex:1;padding:0}.brand-mark{width:34px;height:34px;border-radius:10px;font-size:22px}.brand strong{font-size:21px}.brand small{font-size:9px}
 .sidebar-intro,.sidebar-section,.privacy-note{display:none}
 .sidebar-footer{order:2;margin:0;padding:0}.nav-analysis{width:auto;text-align:center;border:1px solid #3c5176;border-radius:10px;padding:8px 9px;min-height:40px;font-size:12px}.nav-analysis span{margin-right:3px}
 .lesson-nav{order:3;flex:0 0 100%;display:flex;gap:7px;overflow-x:auto;scrollbar-width:thin;scroll-snap-type:x proximity;padding:1px 0 5px}
 .lesson-item{min-width:max-content;width:auto;flex:none;scroll-snap-align:center;display:flex;align-items:center;min-height:42px;padding:7px 10px;border-radius:10px;gap:6px}
 .lesson-item .lesson-glyph{margin:0;flex:0 0 25px;width:25px;height:25px;border-radius:7px;font-size:15px}.lesson-item strong{font-size:12px;white-space:nowrap}
 .lesson-item small,.lesson-number{display:none}
 .topbar{display:none}
 .consent-banner{padding:8px 16px;gap:5px;display:flex;flex-direction:row;align-items:center;flex-wrap:wrap}
 .consent-banner strong{font-size:13px;margin:0}.consent-banner p{font-size:12px;line-height:1.3;margin:0}
 .consent-actions{width:auto;gap:6px;margin-left:auto}.consent-actions button{min-height:35px;font-size:12px;padding:5px 10px}
 .content{padding:15px 16px 28px}
 .welcome{margin:0 0 10px}.welcome h1{font-size:26px;margin:3px 0}.welcome p{font-size:13px;margin:4px 0 0}.lesson-badge{width:42px;height:42px;font-size:20px}
 .eyebrow,.eyebrow.dark{font-size:11px}
 .learning-path{gap:5px;margin-bottom:12px;flex-wrap:nowrap;overflow-x:auto;padding-bottom:2px}.learning-path .phase{white-space:nowrap;font-size:11px;padding:5px 8px}.learning-path .phase strong{font-weight:650}
 .learning-path .path-progress{display:none}
 .body-grid{display:flex;flex-direction:column;gap:12px}.left-content,.right-content{display:contents}
 .exercise-card{order:1;padding:16px;border-radius:14px;width:100%}
 .plot-card{order:2;width:100%;border-radius:14px}
 .tutor-card{order:3;width:100%;padding:17px}
 .theory-card{order:4;width:100%;padding:15px}
 .exercise-head{margin-bottom:10px}.exercise-head h2{font-size:19px;margin:5px 0 0}.task-icon{width:30px;height:30px;font-size:18px}
 .question-box{padding:12px 13px;margin-bottom:11px}.question-label{font-size:11px}
 .question-formula{font-size:20px;margin:7px 0}.question-box p{font-size:15px;line-height:1.4}
 .answer-label{font-size:14px;margin:0 0 5px}.input-wrap input{height:44px;min-height:44px}.field-foot{font-size:12px;margin:6px 0 9px}.primary-button{min-height:46px}
 .practice-footer{padding-top:8px;margin-top:9px}
 .plot-toolbar{padding:8px 12px;min-height:46px;font-size:11px;flex-wrap:wrap}.mini-button{font-size:11px;min-height:38px}
 .plot-bottom{padding:9px 12px;font-size:12px}.explore-controls{padding:10px 12px}.slider-row{gap:8px}.parameter{font-size:13px}
 .theory-card h3{margin:0 0 5px}.theory-card p{font-size:13px}
 .main-footer{margin-top:12px}
}
@media(max-width:350px){.content{padding:12px 10px}.consent-banner{padding:8px 10px}.brand small{display:none}.lesson-nav{gap:5px}.learning-path .phase{font-size:10px;padding:5px 6px}}

/* MathLab 1.3 — Discovery Engine. A learning activity, not another KPI widget. */
.discovery-card{background:#fff;border:1px solid #cddaf0;border-radius:17px;padding:22px;box-shadow:0 16px 38px #12254412;margin-bottom:16px;min-width:0}
.discovery-top{display:flex;gap:12px;align-items:center;justify-content:space-between;margin-bottom:12px}
.discovery-kicker{color:#365caa;font-size:12px;letter-spacing:.055em;font-weight:800}
.discovery-status{background:#eaf3fa;color:#315977;font-size:12px;border-radius:999px;padding:5px 10px;white-space:nowrap;font-weight:750}
.discovery-progress{display:flex;flex-wrap:wrap;gap:5px;margin:0 0 18px}
.discovery-progress span{font-size:11px;color:#667892;border:1px solid #e1e7f0;border-radius:6px;padding:5px 7px}
.discovery-progress span.current{background:#335fe1;border-color:#335fe1;color:#fff;font-weight:800}
.discovery-progress span.done{background:#e9f7ee;border-color:#bfdfd0;color:#20684e}
.discovery-card h3{margin:0 0 11px;font-size:clamp(19px,1.8vw,23px);line-height:1.3;letter-spacing:-.02em;color:#182f54}
.discovery-card p{margin:0 0 14px;color:#344c6c;font-size:15px;line-height:1.55}
.discovery-options{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}
.discovery-options.vertical{grid-template-columns:1fr}
.discovery-option{background:#f2f6ff;color:#244ca7;border:1px solid #bdcffa;border-radius:11px;min-height:48px;padding:10px 9px;font-size:14px;font-weight:750;cursor:pointer;transition:background .12s ease,transform .12s ease}
.discovery-option:hover{background:#e5edff;transform:translateY(-1px)}
.discovery-option:focus-visible,.discovery-advance:focus-visible{outline:3px solid #28a786;outline-offset:3px}
.discovery-diagram-note{margin-top:8px}
.discovery-plot{display:block;width:100%;max-height:270px;height:auto;aspect-ratio:460/220;border-radius:12px;margin:8px 0 12px}
.discovery-slider{display:grid;gap:8px;background:#f2f6fd;border:1px solid #dce5f3;border-radius:12px;padding:14px;color:#213a60;font-size:15px}
.discovery-slider span{display:flex;justify-content:space-between}
.discovery-slider input{width:100%;min-height:40px;accent-color:#335fe1;cursor:pointer}
.discovery-measurement{margin-top:9px;font-size:14px;color:#324c70;background:#eff6f2;border:1px solid #c7e5d5;border-radius:8px;padding:10px 12px}
.discovery-advance{display:inline-flex;align-items:center;justify-content:center;background:#335fe1;color:#fff;border:1px solid #335fe1;border-radius:10px;min-height:48px;padding:10px 17px;font-size:15px;font-weight:800;cursor:pointer;margin-top:10px}
.discovery-advance:not(:disabled):hover{background:#244abb}
.discovery-advance:disabled{background:#eef2f9;color:#667a95;border-color:#d8e1f0;cursor:not-allowed;opacity:1}
.discovery-card .discovery-help{font-size:13px;margin:8px 0 0;color:#5b6e87}
.discovery-card .discovery-privacy{border-top:1px solid #e6ecf5;margin:18px 0 0;padding-top:10px;font-size:12px;color:#5c6e87}
.discovery-card .discovery-transfer-formula{font-size:22px;font-family:'Cambria Math',Georgia,serif;font-weight:700;color:#1f4288;padding:15px;background:#f1f6ff;border-radius:9px;margin-bottom:15px}
#discovery-transfer-form{display:grid;gap:8px}
#discovery-transfer-form label{font-size:14px;font-weight:800;color:#324a67}
#discovery-transfer-answer{border:1.5px solid #b8cae6;border-radius:9px;min-height:48px;padding:10px 12px;background:#fff;font-size:16px;width:100%}
#discovery-transfer-form .discovery-advance{margin-top:2px;width:100%}
.discovery-feedback{color:#79542b;background:#fff6e6;border-radius:8px;font-size:14px;padding:10px 12px;margin-top:10px;line-height:1.5}
.discovery-feedback:empty{display:none}
.discovery-done{background:#eaf9f0;border:1px solid #bedcca;border-radius:12px;padding:16px}
.discovery-done strong{color:#146146;font-size:18px}
.discovery-done p{margin:10px 0 0;color:#275a46}
@media(max-width:740px){.discovery-card{padding:14px;margin-bottom:12px}.discovery-top{gap:6px;align-items:start}.discovery-kicker{font-size:11px;line-height:1.4}.discovery-progress{gap:4px;margin-bottom:12px}.discovery-progress span{font-size:10px;padding:4px 5px}.discovery-card h3{font-size:20px}.discovery-card p{font-size:14px;margin-bottom:10px}.discovery-options{grid-template-columns:1fr}.discovery-option{min-height:44px}.discovery-plot{max-height:210px}.discovery-slider{padding:10px}.discovery-card .discovery-privacy{font-size:11px;margin-top:12px}}
@media(prefers-reduced-motion:reduce){.discovery-option{transition:none}.discovery-option:hover{transform:none}}

.discovery-skip{display:inline-flex;align-items:center;color:#224eae;font-weight:750;font-size:14px;min-height:44px;text-underline-offset:3px;margin-top:10px;padding:8px 0}
.discovery-skip:focus-visible{outline:3px solid #28a786;outline-offset:4px;border-radius:4px}

.discovery-top .discovery-skip{margin:0;font-size:12px;min-height:32px;flex-shrink:0;padding:3px 5px;white-space:nowrap}

/* Keyboard bypass for the six-lesson navigation. */
.skip-main{position:absolute;left:16px;top:-90px;z-index:9999;background:#fff;color:#173e8a;border:3px solid #3c69e0;border-radius:8px;padding:12px 18px;font-size:16px;font-weight:750}
.skip-main:focus-visible{top:12px;outline:3px solid #249e80;outline-offset:2px}


/* MathLab v1.6 — focused learning canvas, informed by UI Design Pro and usability audit. */
:root{font-family:Inter,"Segoe UI",system-ui,-apple-system,sans-serif;color:#202c45;background:#f7f8fb;--ink:#1a2942;--subtle:#566781;--line:#e7eaf1;--accent:#3659d9;--page:#f7f8fb;--radius:16px}
body{background:var(--page);font-size:15px;line-height:1.5}
.sidebar{width:248px;min-width:248px;background:#fff;color:var(--ink);border-right:1px solid var(--line);padding:26px 15px 18px}
.brand{padding:0 11px 28px;gap:11px}
.brand-mark{width:38px;height:38px;font-size:23px;background:#3659d9;color:#fff;border-radius:12px}
.brand strong{font-size:23px;color:#1a2942;font-weight:800;letter-spacing:-.9px}
.brand small{font-size:9px;color:#64738f;letter-spacing:.055em;font-weight:700}
.sidebar-section{font-size:13px;color:#58677c;text-transform:none;letter-spacing:0;padding:12px 13px 10px;font-weight:750}
.sidebar-section span{font-size:12px;color:#8893a4}
.lesson-nav{gap:4px}
.lesson-item{min-height:56px;border-radius:11px;color:#45536e;gap:10px;padding:9px 10px}
.lesson-item:hover{background:#f0f3fc}
.lesson-item.selected{background:#eff2ff;color:#264ac4;border-color:#dce4ff}
.lesson-glyph{flex:0 0 34px;height:34px;background:#f1f3f8;color:#57667d;font-size:19px;border-radius:9px}
.lesson-item.selected .lesson-glyph{background:#dfe7ff;color:#3455cc}
.lesson-item strong{font-size:13px;font-weight:720}
.lesson-item small{font-size:11px;color:#7b8798;margin-top:2px}
.lesson-number{font-size:10px;color:#9ba5b6}
.sidebar-footer{padding-top:16px;border-top:1px solid var(--line)}
.nav-analysis{color:#4e5e77;font-size:13px;min-height:44px;display:flex;justify-content:space-between;align-items:center;padding:10px 13px}
.nav-analysis:hover,.nav-analysis.active{background:#eff2ff;color:#3355cd}
.nav-analysis span{font-size:14px;margin:0}
.privacy-note{background:transparent;border:0;margin-top:12px;padding:8px 13px;gap:9px}
.privacy-note>span{font-size:18px;color:#7284ab}
.privacy-note strong{color:#57677f;font-size:12px}
.privacy-note small{color:#8896a9;font-size:11px;margin-top:1px}
.main-panel{background:var(--page)}
.topbar{height:57px;background:rgba(255,255,255,.8);border-bottom:1px solid var(--line);padding:0 clamp(24px,3vw,44px)}
.crumb{font-size:13px;letter-spacing:0;text-transform:none;color:#5b6b80;font-weight:670}
.topbar-note{font-size:12px;color:#7a879a}
.content{max-width:1380px;padding:30px clamp(24px,3vw,44px) 20px}
.welcome{margin-bottom:20px}
.welcome h1{font-size:clamp(29px,2.7vw,37px);line-height:1.16;letter-spacing:-1.3px;margin:5px 0 6px;color:var(--ink)}
.welcome p{font-size:14px;color:#58677b;line-height:1.45}
.eyebrow.dark{font-size:12px;color:#586b8f;letter-spacing:.025em;text-transform:none}
.body-grid{grid-template-columns:minmax(0,1.18fr) minmax(340px,1fr);gap:19px}
.left-content,.right-content{gap:14px}
.discovery-card,.exercise-card,.tutor-card,.analysis-card{border:1px solid #e3e7ef;box-shadow:0 2px 12px rgba(22,38,65,.035);background:#fff;border-radius:16px}
.discovery-card{padding:22px;margin-bottom:0}
.discovery-top{margin-bottom:13px}
.discovery-kicker{font-size:12px;color:#405ac7;font-weight:800;letter-spacing:.02em}
.discovery-progress{margin:0 0 17px;gap:5px}
.discovery-progress span{border-radius:999px;border:1px solid #ecedf3;background:#f7f8fb;color:#748197;font-size:11px;padding:6px 9px}
.discovery-progress span.current{background:#e9eeff;color:#3052c7;border-color:#d2defe;font-weight:800}
.discovery-progress span.done{background:#eff9f4;border-color:#d7eee1;color:#277554}
.discovery-card h3{font-size:23px;color:var(--ink);line-height:1.24;letter-spacing:-.04em;margin-bottom:8px}
.discovery-card p{font-size:14px;color:#4c5d74;line-height:1.53}
.discovery-option{background:#fff;border:1px solid #cbd7f3;color:#3151b6;border-radius:11px;min-height:48px;box-shadow:none;font-size:14px}
.discovery-option:hover{background:#f1f5ff;border-color:#9bafe5}
.discovery-card .discovery-privacy{display:none}
.discovery-skip{font-size:13px;color:#536b97}
.exercise-card{padding:22px}
.exercise-head{margin-bottom:15px}
.exercise-head h2{color:var(--ink);font-size:20px;letter-spacing:-.45px;margin:0}
.exercise-head h2 span{color:#405bc9}
.question-box{background:#f8f9fc;border-color:#e6eaf3;padding:18px;border-radius:13px;margin-bottom:17px}
.question-formula{font-size:clamp(19px,1.7vw,25px);color:#233d79;margin:0 0 10px}
.question-box p{font-size:15px;line-height:1.5;color:#475973}
.answer-label{font-size:14px;color:#33455f;margin-bottom:8px}
.input-wrap{border-color:#cfd7e5;border-radius:11px}
.input-wrap input{height:50px;font-size:16px}
.field-foot{font-size:12px;color:#69778d;margin:7px 0 14px}
.primary-button{border-radius:11px;min-height:48px;font-size:14px;background:#3659d9;box-shadow:none;font-weight:730;transition:background .15s ease,transform .15s ease}
.primary-button:hover:not(:disabled){background:#2849c0;transform:translateY(-1px)}
.practice-footer{margin-top:16px;padding-top:13px}
.practice-footer span,.link-button{font-size:13px}
.tutor-card{background:#f8f9ff;border-color:#e5e9fa;padding:20px}
.tutor-top h3{font-size:16px;color:#253960;margin:0}
.mode-switch{margin-top:14px;background:#edf0f8}
.mode-switch button{font-size:13px}
.hint-button{background:#fff;border-color:#d6dff4;color:#3b55b8}
.plot-card{border-radius:16px;box-shadow:none}
.plot-toolbar{min-height:55px;font-size:14px;font-weight:720;letter-spacing:0;padding:0 19px}
.plot-sub{font-size:12px;letter-spacing:0}
.plot-bottom{padding:12px 19px;font-size:12px}
.mini-button{font-size:12px;min-height:38px}
.explore-controls{padding:18px 19px}
.explore-heading{font-size:13px;text-transform:none;font-weight:700}
.main-footer{font-size:12px;color:#738198;padding-top:18px}
.consent-banner{background:#edf3ff;border-bottom:1px solid #dce6f8;padding:12px clamp(24px,3vw,44px);gap:14px}
.consent-banner strong{font-size:14px;color:#203a66}
.consent-banner p{font-size:12px;color:#4d6181;line-height:1.4;margin-top:1px}
.consent-actions button{min-height:40px;font-size:13px}
.consent-actions button:first-child{background:#3659d9;border-color:#3659d9}
.analysis-page .welcome{margin-bottom:20px}
.analysis-card{padding:23px}
.analysis-card h2{font-size:20px;color:#21324a}
.analysis-card p{font-size:14px}
@media(max-width:1150px){.body-grid{grid-template-columns:minmax(0,1fr) minmax(320px,1fr)}}
@media(max-width:900px){.body-grid{grid-template-columns:1fr}}
@media(max-width:740px){
 .sidebar{background:#fff;position:static;border-right:0;border-bottom:1px solid #e5e8f0;min-width:0;width:100%;height:auto;padding:12px 16px 9px;gap:5px 12px;}
 .brand{padding:0;flex:1}.brand-mark{width:33px;height:33px;font-size:21px}.brand strong{font-size:20px}.brand small{display:none}
 .sidebar-footer{order:2;padding:0;border:0;margin:0}.nav-analysis{width:auto;min-height:35px;padding:7px 11px;border:1px solid #e4e8f1;background:#f8faff;font-size:12px}
 .nav-analysis span{display:none}
 .lesson-nav{order:3;padding:5px 0 0;gap:5px;flex:0 0 100%}
 .lesson-item{min-height:38px;padding:5px 10px;border-radius:9px;gap:7px}
 .lesson-item .lesson-glyph{background:#edf0f7;color:#43587e;flex:0 0 24px;height:24px;font-size:14px}
 .lesson-item.selected .lesson-glyph{background:#dbe5ff;color:#3355c6}
 .lesson-item strong{font-size:12px}
 .consent-banner{padding:9px 16px;gap:6px;align-items:center}
 .consent-banner strong{font-size:13px}
 .consent-banner p{font-size:12px;line-height:1.35}
 .consent-actions{margin-left:0;width:100%;display:flex;justify-content:flex-start}
 .consent-actions button{min-height:36px;padding:6px 11px;font-size:12px}
 .content{padding:15px 15px 25px}
 .welcome{margin:0 0 15px}.welcome h1{font-size:27px;margin:3px 0 4px}.welcome p{font-size:13px}
 .body-grid{gap:11px}
 .discovery-card{padding:16px;border-radius:14px;margin-bottom:0}
 .discovery-top{margin-bottom:9px}.discovery-progress{gap:5px;margin-bottom:13px}
 .discovery-progress span{font-size:10px;padding:4px 6px}
 .discovery-card h3{font-size:22px;line-height:1.2}
 .discovery-card p{font-size:14px}
 .discovery-option{min-height:46px;font-size:14px}
 .exercise-card{padding:17px;border-radius:14px}
 .question-box{padding:14px;margin-bottom:13px}
 .question-formula{font-size:22px;margin:0 0 9px}
 .question-box p{font-size:15px}
 .field-foot{font-size:12px;margin-bottom:12px}
 .primary-button{font-size:14px}
 .tutor-card{padding:16px;border-radius:14px}
 .plot-toolbar{padding:8px 13px;min-height:46px;font-size:13px;flex-wrap:wrap}
 .plot-bottom{padding:10px 13px;font-size:12px}
 .main-footer{font-size:12px}
}
@media(max-width:350px){.content{padding:12px 10px}.consent-banner{padding:9px 10px}.discovery-progress span{font-size:9px;padding:4px 5px}}
@media(prefers-reduced-motion:reduce){.primary-button{transition:none}.primary-button:hover:not(:disabled){transform:none}}

/* Contrast fixes for small secondary UI labels. */
.brand small,.lesson-item small,.sidebar-section span,.lesson-number,.topbar-note,.main-footer{color:#57687e}
.discovery-progress span{color:#52647c}