.learning-shell,.lesson-shell,.educator-shell{max-width:1420px;margin:auto}.learning-hero{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:24px;align-items:end;padding:8px 0 24px}.learning-hero h1{font-size:clamp(3rem,6.2vw,6.3rem);line-height:.9;letter-spacing:-.06em;margin:7px 0 15px}.learning-hero p{max-width:830px;color:#c9c2d6;font-size:1.06rem}.learning-meta{display:grid;gap:8px;justify-items:end}.learning-meta span{border:1px solid #31506d;border-radius:999px;padding:9px 12px;background:#091b32;color:#cfd9e6;font-size:.82rem}.core-kicker{color:#6ee0d5;letter-spacing:.16em;text-transform:uppercase;font-size:.75rem;font-weight:800}.course-ribbon{display:flex;gap:9px;overflow-x:auto;padding:6px 0 16px;scrollbar-width:thin}.course-ribbon button{flex:0 0 auto;border:1px solid #31506d;border-radius:999px;background:#0b203a;color:#edf5fa;padding:10px 15px;cursor:pointer}.course-ribbon button.active{background:linear-gradient(135deg,rgba(110,224,213,.17),rgba(185,156,255,.16));border-color:#6ee0d5}.learning-grid{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:18px}.course-stage{min-height:660px;border:1px solid #2e4d69;border-radius:34px;padding:24px;background:radial-gradient(circle at 80% 10%,rgba(185,156,255,.08),transparent 32%),linear-gradient(160deg,#0d2340,#081a31)}.course-head{display:grid;grid-template-columns:1fr auto;gap:18px;align-items:end;padding-bottom:20px;border-bottom:1px solid rgba(92,123,152,.28)}.course-head h2{font-size:clamp(2rem,4vw,3.4rem);margin:4px 0}.course-head p{margin:0;color:#bdc8d6;max-width:700px}.course-glyph{font-size:4.2rem;color:#ffd16f}.lesson-path{position:relative;display:grid;gap:18px;padding:30px 4px 10px}.lesson-path:before{content:"";position:absolute;left:35px;top:26px;bottom:18px;width:2px;background:linear-gradient(#6ee0d5,#b99cff,#ffd16f)}.lesson-node{position:relative;display:grid;grid-template-columns:64px 1fr auto;gap:14px;align-items:center;z-index:1}.lesson-node .node-orb{width:64px;height:64px;border-radius:50%;background:#102b49;border:1px solid #527391;display:grid;place-items:center;font-weight:800;box-shadow:0 0 0 7px #0b2039}.lesson-node.done .node-orb{background:#175a5a;border-color:#6ee0d5}.lesson-node.current .node-orb{border-color:#ffd16f;box-shadow:0 0 0 7px #0b2039,0 0 28px rgba(255,209,111,.22)}.lesson-node a{display:block;padding:16px 18px;border-radius:20px;border:1px solid #294a67;background:#091c34}.lesson-node a:hover{border-color:#6ee0d5}.lesson-node strong{display:block;font-size:1.08rem}.lesson-node small{color:#aab9c9}.lesson-node .mastery{min-width:64px;text-align:right;color:#c8d6e3}.learner-sidebar{display:grid;gap:14px;align-content:start}.learn-card,.backend-card{border:1px solid #2e4d69;background:linear-gradient(160deg,#0c223d,#081a31);border-radius:26px;padding:18px}.learn-card h2,.learn-card h3,.backend-card h2,.backend-card h3{margin:0 0 8px}.learn-card p,.backend-card p{color:#b8c4d2}.big-resume{display:block;border-radius:18px;padding:14px;text-align:center;background:linear-gradient(135deg,#184c55,#392e62);border:1px solid #6ee0d5;font-weight:800}.support-list{display:grid;gap:8px}.support-list label,.toggle-line{display:flex!important;grid-template-columns:none!important;align-items:center;gap:8px}.learning-links{display:grid;gap:7px}.learning-links a{border:1px solid #294a67;border-radius:16px;padding:11px}.learning-links small{display:block;color:#9eafc1}.learning-links strong{display:block}.mastery-meter{height:11px;border-radius:999px;background:#122c46;overflow:hidden;margin:6px 0}.mastery-meter i{display:block;height:100%;width:0;background:linear-gradient(90deg,#6ee0d5,#b99cff,#ffd16f)}
/* Lesson composition: central published lesson with a stable tool rail. */
.lesson-top{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:22px;align-items:end;padding:12px 0 22px}.lesson-top h1{font-size:clamp(2.6rem,5.8vw,5.7rem);line-height:.93;letter-spacing:-.055em;margin:7px 0 10px}.lesson-top p{color:#c3c9d3;max-width:800px}.lesson-top-meta{display:grid;justify-items:end;gap:7px}.lesson-top-meta span{border:1px solid #304d67;border-radius:999px;padding:8px 10px;color:#c5d2df}.lesson-grid{display:grid;grid-template-columns:minmax(0,1fr) 330px;gap:18px}.lesson-main{min-width:0}.lesson-reader{border:1px solid #2d4e6c;border-radius:34px;background:linear-gradient(160deg,#0d2340,#081a30);overflow:hidden}.rep-rail{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:#284761;border-bottom:1px solid #34536d}.rep-rail button{border:0;background:#0c213b;padding:13px 8px;color:#c4cfdb;cursor:pointer}.rep-rail button.active{background:#173956;color:#fff;box-shadow:inset 0 -3px #6ee0d5}.representation-stage{padding:22px;background:radial-gradient(circle at 80% 15%,rgba(185,156,255,.08),transparent 38%)}.representation-stage h2{margin:0 0 10px}.representation-box{min-height:170px;border-radius:26px;border:1px solid #345572;background:#081a31;padding:22px;display:grid;place-items:center;text-align:center}.representation-box .big-symbol{font-family:Cambria Math,Georgia,serif;font-size:clamp(2.3rem,6vw,5rem);line-height:1.05;color:#f4f0ff}.representation-box .plain-big{max-width:720px;font-size:1.25rem;line-height:1.55}.lesson-section{padding:26px 28px;border-top:1px solid rgba(84,116,146,.25);max-width:var(--lesson-width,860px);margin:auto}.lesson-section h2{font-size:1.65rem;margin:0 0 10px}.lesson-section p{color:#d4d8df;font-size:1.04rem;line-height:var(--lesson-line,1.65)}.lesson-section.hidden-chunk{display:none}.vocab-strip{display:flex;gap:8px;flex-wrap:wrap;margin:10px 0 18px}.vocab-chip{border:1px solid #36566f;border-radius:999px;background:#0b2039;padding:8px 11px;cursor:pointer}.vocab-chip[aria-expanded=true]{border-color:#ffd16f}.vocab-definition{padding:13px 16px;border-radius:18px;background:rgba(255,209,111,.07);border:1px solid rgba(255,209,111,.24);margin-bottom:14px}.worked-example{border-left:4px solid #b99cff;background:rgba(185,156,255,.06);padding:18px 20px;margin:18px 0;border-radius:0 20px 20px 0}.worked-example ol{padding-left:22px}.practice-block{padding:22px 28px;border-top:1px solid #294966}.practice-question{padding:17px;border:1px solid #31516d;border-radius:20px;background:#081b32;margin:12px 0}.practice-options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;margin-top:12px}.practice-options button{border:1px solid #365976;background:#102a46;border-radius:14px;padding:12px;text-align:left;cursor:pointer}.practice-options button.correct{border-color:#6ee0d5;background:#174848}.practice-options button.incorrect{border-color:#ff8580;background:#4a252e}.practice-feedback{min-height:24px;color:#c4d0dd;margin-top:8px}.field-note-call{display:grid;grid-template-columns:1fr auto;gap:15px;align-items:center;padding:18px 20px;border-radius:22px;background:linear-gradient(135deg,rgba(110,224,213,.08),rgba(185,156,255,.08));border:1px solid #355877;margin:20px 28px}.reader-dock{position:sticky;top:14px;height:max-content;border:1px solid #31506d;border-radius:28px;background:#0a1d35;padding:17px;display:grid;gap:13px}.reader-dock h3{margin:0}.reader-dock label{display:grid;gap:5px;font-size:.86rem;color:#c8d3df}.reader-dock select,.reader-dock textarea,.reader-dock button{width:100%;min-height:44px}.reader-dock button{border:1px solid #375976;background:#102d49;border-radius:14px;cursor:pointer}.mini-grid{display:grid;grid-template-columns:1fr 1fr;gap:7px}.scratchpad{min-height:120px;background:#07182d;color:#fff;border:1px solid #36546e;border-radius:14px;padding:10px;resize:vertical}.lesson-symbol-hidden [data-math-symbol]{display:none!important}.lesson-words-hidden [data-math-words]{display:none!important}
/* LMS */
.educator-grid{display:grid;grid-template-columns:210px minmax(0,1fr);gap:16px}.backend-nav{padding:10px;display:grid;gap:6px;align-content:start}.backend-nav button{border:0;background:transparent;color:#bdc9d6;text-align:left;padding:11px;border-radius:13px;cursor:pointer}.backend-nav button.active{background:#153753;color:#fff}.backend-view{display:none}.backend-view.active{display:block}.overview-grid{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(300px,.9fr);gap:14px}.progress-orbit canvas{display:block;width:100%;height:360px}.course-progress-row{display:grid;grid-template-columns:130px 1fr 48px;gap:10px;align-items:center;padding:8px 0}.course-progress-bar{height:10px;background:#102b46;border-radius:999px;overflow:hidden}.course-progress-bar i{display:block;height:100%;background:linear-gradient(90deg,#6ee0d5,#b99cff)}.event-row,.attempt-row{display:grid;grid-template-columns:auto 1fr auto;gap:10px;padding:10px 0;border-bottom:1px solid rgba(79,108,136,.23)}.event-row:last-child,.attempt-row:last-child{border-bottom:0}.event-dot{width:11px;height:11px;border-radius:50%;background:#6ee0d5;margin-top:5px}.plan-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.plan-list label{display:flex;align-items:flex-start;gap:8px;border:1px solid #2f506c;border-radius:15px;padding:10px;background:#091c33}.data-actions{display:flex;flex-wrap:wrap;gap:8px}.data-actions button,.core-btn{border:1px solid #365876;background:#102c49;border-radius:14px;padding:10px 13px;color:#fff;cursor:pointer}.support-summary-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:8px;margin:12px 0}.support-summary-grid div{border:1px solid #31506d;border-radius:15px;padding:11px;background:#091c33}
@media(max-width:1050px){.learning-grid,.lesson-grid{grid-template-columns:1fr}.learner-sidebar{grid-template-columns:repeat(3,1fr)}.reader-dock{position:static;grid-template-columns:repeat(3,minmax(0,1fr));align-items:end}.reader-dock h3{grid-column:1/-1}.overview-grid{grid-template-columns:1fr}.educator-grid{grid-template-columns:1fr}.backend-nav{display:flex;overflow-x:auto}.backend-nav button{white-space:nowrap}}
@media(max-width:760px){.learning-hero,.lesson-top{grid-template-columns:1fr}.learning-meta,.lesson-top-meta{justify-items:start}.learning-grid{gap:12px}.course-stage{padding:16px;border-radius:26px;min-height:0}.course-head{grid-template-columns:1fr}.lesson-node{grid-template-columns:54px minmax(0,1fr);gap:10px}.lesson-node .node-orb{width:54px;height:54px}.lesson-node .mastery{grid-column:2;text-align:left}.lesson-path:before{left:31px}.learner-sidebar{grid-template-columns:1fr}.reader-dock{grid-template-columns:1fr 1fr}.lesson-reader{border-radius:25px}.rep-rail{grid-template-columns:repeat(2,1fr)}.lesson-section,.practice-block{padding:20px 17px}.field-note-call{margin:16px 17px;grid-template-columns:1fr}.practice-options{grid-template-columns:1fr}.plan-list{grid-template-columns:1fr}.support-summary-grid{grid-template-columns:1fr}.progress-orbit canvas{height:310px}}
@media(max-width:430px){.reader-dock{grid-template-columns:1fr}.learning-hero h1{font-size:3.6rem}.lesson-top h1{font-size:3.15rem}.course-ribbon{margin-right:-8px}}