:root{--accent:#2dd4bf;--accent-ink:#04221f;--accent-soft:#2dd4bf24;--bg:#061214;--surface:#ffffff0d;--ink:#e8f3f2;--ink-2:#a9c1bf;--ink-3:#7b9593;--line:#ffffff1f;--warm:#fbbf24;--ok:#34d399;--ok-soft:#34d39924;--bad:#f87171;--bad-soft:#f8717124;--head-h:68px;--shadow:0 20px 50px #00000059;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}body{background:radial-gradient(1200px 700px at 75% -10%, #2dd4bf29, transparent 60%), radial-gradient(900px 600px at -10% 110%, #38bdf81a, transparent 60%), var(--bg);background-attachment:fixed}.muted{color:var(--ink-2)}.small{font-size:.86rem}.eyebrow{color:var(--accent)}.card{background:var(--surface);border-color:var(--line);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px)}.btn--primary{color:var(--accent-ink);background:linear-gradient(135deg,#5eead4,#14b8a6);box-shadow:0 10px 30px #14b8a659}.btn--primary:hover{background:linear-gradient(135deg,#99f6e4,#2dd4bf)}.btn--ghost{border-color:var(--line);color:var(--ink);background:#ffffff0f}.btn--ghost:hover{color:var(--accent);border-color:#2dd4bf80}.btn--soft{background:var(--accent-soft);color:var(--accent)}.btn--lg{min-height:54px;padding:14px 26px;font-size:1.02rem}.icon-btn{border-color:var(--line);color:var(--ink-2);background:#ffffff0f}.input{border-color:var(--line);color:var(--ink);background:#ffffff0f}.dialog{color:var(--ink);border:1px solid var(--line);background:#0c1d20}.lesson-head{z-index:30;height:var(--head-h);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-bottom:1px solid var(--line);background:#061214b8;align-items:center;gap:16px;padding:0 clamp(14px,2.4vw,32px);display:flex;position:sticky;top:0}.lx--home .lesson-head{background:0 0;border-bottom-color:#0000}.lesson-brand{color:var(--ink);flex:none;align-items:center;gap:12px;min-width:0;text-decoration:none;display:flex}.lesson-brand>span:last-child{min-width:0}.lesson-brand strong{font-size:1rem;display:block}.lesson-brand small{color:var(--ink-3);white-space:nowrap;text-overflow:ellipsis;font-size:.76rem;display:block;overflow:hidden}.lesson-brand__mark{background:linear-gradient(135deg,#5eead4,#0d9488);border-radius:12px;flex:none;place-items:center;width:40px;height:40px;display:grid;box-shadow:0 6px 20px #14b8a659}.lesson-brand__mark svg{fill:none;stroke:#04221f;stroke-width:2.4px;stroke-linecap:round;width:26px;height:26px}.lesson-brand__mark svg circle{fill:#04221f;stroke:none}.lesson-nav{border:1px solid var(--line);scrollbar-width:none;background:#ffffff0d;border-radius:999px;gap:4px;margin:0 auto;padding:4px;display:flex;overflow-x:auto}.lesson-nav::-webkit-scrollbar{display:none}.lesson-nav a{color:var(--ink-2);white-space:nowrap;border-radius:999px;align-items:center;gap:7px;padding:7px 14px;font-size:.9rem;font-weight:600;text-decoration:none;display:inline-flex}.lesson-nav a b{background:#ffffff14;border-radius:50%;place-items:center;width:20px;height:20px;font-size:.74rem;display:inline-grid}.lesson-nav a:hover{color:var(--ink)}.lesson-nav a[aria-current=page]{background:var(--accent);color:var(--accent-ink)}.lesson-nav a[aria-current=page] b{background:#04221f33}.lesson-head__tools{flex:none;gap:8px;display:flex}.lesson-main{min-height:calc(100svh - var(--head-h));padding:28px 0 70px}.lx--stage .lesson-main,.lx--home .lesson-main{padding:0}.section-head{margin-bottom:22px}.section-head h2{letter-spacing:-.01em;font-size:clamp(1.7rem,3.4vw,2.6rem)}.section-head p{color:var(--ink-2);max-width:760px}.section-head--row{flex-wrap:wrap;justify-content:space-between;align-items:flex-end;gap:16px;display:flex}.step-pager{justify-content:space-between;gap:12px;margin-top:32px;display:flex}.lx--home .lesson-head{position:absolute;top:0;bottom:auto;left:0;right:0}.ov-hero{min-height:100svh;padding:calc(var(--head-h) + 10px) clamp(16px, 4vw, 64px) 30px;grid-template-columns:minmax(0,.95fr) minmax(0,1.05fr);align-items:center;gap:20px;display:grid;position:relative}.ov-text h1{letter-spacing:-.03em;margin-bottom:20px;font-size:clamp(2.6rem,6.4vw,5.4rem);line-height:1}.ov-text h1 span{background:linear-gradient(90deg,#5eead4,#38bdf8 60%,#a78bfa);color:#0000;-webkit-background-clip:text;background-clip:text;display:block}.lead{color:var(--ink-2);max-width:560px;font-size:clamp(1rem,1.5vw,1.15rem)}.ov-stats{color:var(--ink-2);flex-wrap:wrap;gap:14px 34px;margin:26px 0 30px;font-size:.92rem;display:flex}.ov-stats b{color:var(--ink);font-size:2.2rem;line-height:1.05;display:block}.ov-actions{flex-wrap:wrap;gap:12px;display:flex}.ov-model{height:min(86svh,860px);position:relative}.ov-model:before{content:"";filter:blur(10px);background:radial-gradient(circle,#2dd4bf38,#0000 65%);border-radius:50%;position:absolute;top:8%;bottom:8%;left:10%;right:10%}.viewer--home{height:100%!important;box-shadow:none!important;background:0 0!important}.ov-model__hint{border:1px solid var(--line);color:var(--ink-2);white-space:nowrap;background:#ffffff0f;border-radius:999px;padding:6px 14px;font-size:.82rem;position:absolute;bottom:6px;left:50%;transform:translate(-50%)}.ov-steps{grid-template-columns:repeat(4,1fr);gap:14px;width:min(1240px,100% - 32px);margin:0 auto;display:grid}.ov-step{background:var(--surface);border:1px solid var(--line);color:var(--ink);border-radius:18px;gap:14px;padding:20px;text-decoration:none;transition:transform .2s,border-color .2s;display:flex}.ov-step:hover{border-color:#2dd4bf80;transform:translateY(-3px)}.ov-step__num{width:40px;height:40px;color:var(--accent-ink);background:linear-gradient(135deg,#5eead4,#0d9488);border-radius:50%;flex:none;place-items:center;font-weight:700;display:grid}.ov-step strong{font-size:1.05rem;display:block}.ov-step small{color:var(--ink-3);margin-left:4px;font-weight:500}.ov-step p{color:var(--ink-2);margin:6px 0 0;font-size:.9rem}.ov-goals{background:var(--surface);border:1px solid var(--line);border-radius:20px;width:min(1240px,100% - 32px);margin:36px auto 70px;padding:26px 30px}.ov-goals h2{font-size:1.2rem}.ov-goals ol{color:var(--ink-2);grid-template-columns:1fr 1fr;gap:8px 32px;margin:0;padding-left:22px;display:grid}.mcq-q{margin:8px 0 18px;font-size:clamp(1.25rem,2.4vw,1.7rem)}.mcq-options{gap:10px;display:grid}.mcq-opt{border:1.5px solid var(--line);width:100%;min-height:58px;color:var(--ink);text-align:left;background:#ffffff0a;border-radius:14px;align-items:center;gap:14px;padding:12px 16px;font-size:1.02rem;font-weight:500;display:flex}.mcq-opt b{background:var(--accent-soft);width:34px;height:34px;color:var(--accent);border-radius:50%;flex:none;place-items:center;display:inline-grid}.mcq-opt:not([disabled]):hover{border-color:var(--accent);background:#2dd4bf14}.mcq-opt.is-right{border-color:var(--ok);background:var(--ok-soft)}.mcq-opt.is-right b{background:var(--ok);color:#052e1c}.mcq-opt.is-wrong{border-color:var(--bad);background:var(--bad-soft)}.mcq-opt.is-wrong b{background:var(--bad);color:#3a0a0a}.mcq-opt.is-dim{opacity:.45}.mcq-opt[disabled]{cursor:default}.mcq-feedback{text-align:left;border:1px solid var(--line);border-radius:14px;margin-top:14px;padding:14px 16px}.mcq-feedback.ok{background:var(--ok-soft)}.mcq-feedback.ok strong{color:var(--ok)}.mcq-feedback.bad{background:var(--bad-soft)}.mcq-feedback.bad strong{color:var(--bad)}.mcq-feedback strong{align-items:center;gap:6px;display:flex}.mcq-feedback strong svg{width:18px;height:18px}.mcq-feedback p{color:var(--ink-2);margin:6px 0 10px}.dialog .mcq-q{text-align:left}.score-line{color:var(--ink-2);justify-content:space-between;font-size:.92rem;display:flex}.score-line b{color:var(--accent);font-size:1.15rem}.progress{background:#ffffff14;border-radius:999px;height:6px;margin:8px 0 16px;overflow:hidden}.progress i{background:linear-gradient(90deg,#5eead4,#38bdf8);height:100%;transition:width .3s;display:block}.result-box{text-align:center;justify-items:center;gap:8px;padding:20px 8px;display:grid}.result-box>svg{width:52px;height:52px;color:var(--warm)}.result-box--row{text-align:left;grid-template-columns:auto 1fr auto;place-items:center start;width:100%;padding:6px}.result-box--row h3{margin:0;font-size:1.05rem}.result-box--row p{margin:4px 0 0}.warmup-grid{grid-template-columns:minmax(0,1.2fr) minmax(0,1fr);align-items:center;gap:24px;display:grid}.puzzle{aspect-ratio:1;border-radius:24px;justify-self:center;width:min(100%,100svh - 250px,640px);padding:0;position:relative;overflow:hidden;box-shadow:0 30px 70px #00000073}.puzzle-art{width:100%;height:100%}.puzzle-tiles{background:#061214;grid-template-rows:repeat(2,1fr);grid-template-columns:repeat(3,1fr);gap:4px;padding:4px;display:grid;position:absolute;top:0;bottom:0;left:0;right:0}.puzzle-tile{color:#fff;text-shadow:0 4px 16px #0000004d;background:linear-gradient(145deg,#0f766e,#14b8a6);border:none;border-radius:14px;place-items:center;font-size:clamp(2.4rem,7vw,4.6rem);font-weight:700;transition:transform .45s,opacity .45s,background .2s;display:grid}.puzzle-tile:nth-child(2n){background:linear-gradient(145deg,#0e7490,#22d3ee)}.puzzle-tile:not([disabled]):hover{background:linear-gradient(145deg,#f59e0b,#fbbf24);transform:scale(.98)}.puzzle-tile.is-open{opacity:0;pointer-events:none;transform:rotateY(90deg)scale(.9)}.puzzle-tiles:has(.is-open){background:0 0}.puzzle-keyword{background:var(--accent);color:var(--accent-ink);letter-spacing:.1em;border-radius:999px;padding:10px 26px;font-size:1.2rem;font-weight:800;animation:.3s pop-in;position:absolute;bottom:18px;left:50%;transform:translate(-50%)}.warmup-side{padding:26px}.warmup-side h3{font-size:1.3rem}.keyword-cells{flex-wrap:wrap;gap:6px;margin:14px 0 18px;display:flex}.keyword-cells span{width:44px;height:52px;color:var(--accent);border:2px dashed #2dd4bf80;border-radius:10px;place-items:center;font-size:1.4rem;font-weight:800;display:grid}.keyword-cells .gap{width:14px}.guess-form{gap:8px;display:flex}.solved-note{background:var(--ok-soft);border-radius:14px;padding:14px}.solved-note strong{color:var(--ok);align-items:center;gap:6px;display:flex}.solved-note strong svg{width:18px}.row-actions{flex-wrap:wrap;gap:8px;display:flex}.stage{height:calc(100svh - var(--head-h));min-height:520px;position:relative}.stage-view{position:absolute;top:0;bottom:0;left:0;right:0}.viewer{border-radius:var(--radius);height:640px;box-shadow:var(--shadow);background:radial-gradient(at 50% 40%,#16343a 0%,#081619 70%);position:relative;overflow:hidden}.viewer--stage{height:100%;box-shadow:none;background:radial-gradient(at 50% 45%,#2dd4bf24 0%,#0000 60%);border-radius:0}.viewer-host,.viewer-canvas{position:absolute;top:0;bottom:0;left:0;right:0}.viewer-canvas canvas{cursor:grab}.viewer-loading{color:#dfeceb;text-align:center;place-content:center;justify-items:center;gap:8px;padding:24px;display:grid;position:absolute;top:0;bottom:0;left:0;right:0}.viewer-loading small{color:#9fb4b3}.viewer-loading__bar{background:#ffffff26;border-radius:999px;width:min(260px,70vw);height:6px;overflow:hidden}.viewer-loading__bar i{background:linear-gradient(90deg,#5eead4,#38bdf8);height:100%;transition:width .2s;display:block}.viewer-views,.viewer-modes{border:1px solid var(--line);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);background:#061214b3;border-radius:999px;gap:4px;padding:4px;display:flex;position:absolute}.viewer-views{top:14px;left:50%;transform:translate(-50%)}.viewer-modes{max-width:calc(100% - 24px);bottom:16px;left:50%;overflow-x:auto;transform:translate(-50%)}.viewer-views button,.viewer-modes button{color:#e2eeed;white-space:nowrap;background:0 0;border:none;border-radius:999px;padding:7px 13px;font-size:.84rem;font-weight:600}.viewer-views button:hover,.viewer-modes button:not([disabled]):hover{background:#ffffff1a}.viewer-modes button[aria-pressed=true]{background:var(--accent);color:var(--accent-ink)}.viewer-modes button[disabled]{opacity:.4;cursor:not-allowed}.viewer-hover{color:#0b1f22;pointer-events:none;background:#ffffffeb;border-radius:999px;padding:6px 14px;font-size:.88rem;font-weight:700;position:absolute;top:64px;left:50%;transform:translate(-50%)}.stage-panel{z-index:2;border:1px solid var(--line);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);scrollbar-width:thin;background:#081619b8;border-radius:20px;max-height:calc(100% - 32px);padding:16px;position:absolute;top:16px;overflow:auto;box-shadow:0 20px 50px #00000059}.stage-panel--left{width:270px;left:16px}.stage-panel--right{width:320px;right:16px}.panel-title{justify-content:space-between;align-items:center;gap:8px;margin-bottom:10px;display:flex}.panel-title .btn svg{width:15px;height:15px}.layer-list{background:#ffffff0a;border-radius:12px;gap:4px;margin-bottom:12px;padding:10px;display:grid}.layer-item{align-items:center;gap:8px;font-size:.9rem;display:flex}.layer-item i{border-radius:50%;width:10px;height:10px}.system-row{width:100%;color:var(--ink);text-align:left;background:0 0;border:none;border-radius:12px;align-items:center;gap:10px;padding:9px 10px;font-size:.94rem;font-weight:600;display:flex}.system-row small{color:var(--ink-3);margin-left:auto;font-weight:500}.system-row:hover{background:#ffffff0f}.system-row.is-active{background:var(--accent-soft);color:var(--accent)}.dot{border-radius:50%;flex:none;width:12px;height:12px;box-shadow:0 0 10px}.dot--all{background:conic-gradient(#c9b98f,#d23b3b,#4c8fd6,#8f6b3e,#9b62c9,#c9b98f)}.topic-chips{flex-wrap:wrap;gap:6px;padding:6px 4px 10px 32px;display:flex}.topic-chip{border:1px solid var(--line);color:var(--ink);background:#ffffff0a;border-radius:999px;padding:5px 11px;font-size:.84rem}.topic-chip:hover{border-color:var(--accent)}.topic-chip.is-active{background:var(--accent);border-color:var(--accent);color:var(--accent-ink)}.info-tag{background:color-mix(in srgb, var(--c) 25%, transparent);color:color-mix(in srgb, var(--c) 55%, #fff);border-radius:999px;align-items:center;gap:6px;margin-bottom:8px;padding:3px 11px;font-size:.8rem;font-weight:700;display:inline-flex}.info-title{justify-content:space-between;align-items:flex-start;gap:8px;display:flex}.info-title .icon-btn{width:34px;height:34px}.explore-info h3{font-size:1.5rem}.explore-info p{color:var(--ink-2)}.explore-info dl{margin:0 0 12px}.explore-info dt{text-transform:uppercase;letter-spacing:.08em;color:var(--accent);font-size:.76rem;font-weight:700}.explore-info dd{margin:2px 0 10px}.task-card{background:#fbbf241a;border:1px solid #fbbf2459;border-radius:14px;padding:12px 14px}.task-card strong{color:var(--warm)}.task-card p{color:var(--ink);margin:4px 0 0}.task-list{gap:6px;margin:0;padding:0;list-style:none;display:grid}.task-list button{border:1px solid var(--line);text-align:left;width:100%;color:var(--ink-2);background:#ffffff08;border-radius:12px;gap:10px;padding:10px;font-size:.86rem;display:flex}.task-list button:hover{border-color:var(--accent)}.task-list .dot{margin-top:5px}.task-list b{color:var(--ink);display:block}.practice{min-height:calc(100svh - var(--head-h));flex-direction:column;display:flex}.practice-head{flex-wrap:wrap;justify-content:space-between;align-items:flex-end;gap:14px;padding:18px 0 14px;display:flex}.practice-head h2{margin:0;font-size:clamp(1.4rem,2.6vw,1.9rem)}.stage--find{flex:1;height:auto;min-height:520px}.seg{border:1px solid var(--line);background:#ffffff0f;border-radius:999px;gap:4px;padding:4px;display:inline-flex}.seg button{color:var(--ink-2);background:0 0;border:none;border-radius:999px;padding:8px 16px;font-weight:600}.seg button[aria-selected=true]{background:var(--accent);color:var(--accent-ink)}.find-prompt{border:1px solid var(--line);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);text-align:center;background:#081619d1;border-radius:18px;padding:12px 26px;position:absolute;top:18px;left:50%;transform:translate(-50%);box-shadow:0 16px 40px #0006}.find-prompt small{color:var(--ink-3);font-size:.8rem;display:block}.find-prompt strong{color:var(--accent);font-size:clamp(1.4rem,2.6vw,2.1rem)}.find-prompt.is-ok{border-color:var(--ok);box-shadow:0 0 0 3px #34d3994d}.find-prompt.is-bad{border-color:var(--bad);box-shadow:0 0 0 3px #f871714d}.find-side h3{font-size:1.3rem}.find-side .btn--primary{width:100%;margin-top:12px}.hint{color:#fde68a;background:#fbbf241a;border-radius:12px;padding:10px 12px;font-size:.92rem}.sort{padding-bottom:30px}.sort-pool{flex-wrap:wrap;gap:10px;min-height:84px;margin-bottom:16px;padding:16px;display:flex}.sort-item{border:1.5px solid var(--line);color:var(--ink);background:#ffffff0d;border-radius:14px;padding:12px 18px;font-size:1rem;font-weight:600}.sort-item:hover{border-color:var(--accent)}.sort-item.is-selected{background:var(--accent);border-color:var(--accent);color:var(--accent-ink);transform:translateY(-3px);box-shadow:0 10px 24px #2dd4bf59}.sort-buckets{grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:12px;display:grid}.sort-bucket{border:2px dashed color-mix(in srgb, var(--c) 60%, transparent);background:color-mix(in srgb, var(--c) 10%, transparent);min-height:130px;color:var(--ink);text-align:left;border-radius:18px;align-content:start;gap:8px;padding:16px;display:grid}.sort-bucket strong{color:color-mix(in srgb, var(--c) 55%, #fff)}.sort-bucket span{flex-wrap:wrap;gap:6px;display:flex}.sort-bucket em{background:color-mix(in srgb, var(--c) 30%, transparent);border-radius:999px;padding:4px 10px;font-size:.84rem;font-style:normal}.sort-bucket.is-armed:hover{background:color-mix(in srgb, var(--c) 20%, transparent);border-style:solid}.sort-bucket.is-shake{border-color:var(--bad);animation:.4s shake}@keyframes shake{20%,60%{transform:translate(-6px)}40%,80%{transform:translate(6px)}}.apply-grid{grid-template-columns:minmax(0,1fr) 320px;align-items:start;gap:20px;display:grid}.quiz{padding:clamp(18px,3vw,30px)}.apply-side{gap:14px;display:grid}.qr-card,.discuss{padding:20px}.qr-card{text-align:center}.qr-card .qr-box{width:204px}.discuss ol{color:var(--ink-2);gap:8px;margin:0;padding-left:20px;display:grid}.plan{margin-bottom:18px;padding:8px 22px}.plan-row{border-bottom:1px solid var(--line);gap:14px;padding:16px 0;display:flex}.plan-row:last-child{border-bottom:none}.plan-num{width:36px;height:36px;color:var(--accent-ink);background:linear-gradient(135deg,#5eead4,#0d9488);border-radius:50%;flex:none;place-items:center;font-weight:700;display:grid}.plan-row small{color:var(--accent);margin-left:6px;font-weight:600}.plan-row p{color:var(--ink-2);margin:4px 0 0}.teacher-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;display:grid}.teacher-card{padding:22px}.teacher-card h3{font-size:1.1rem}.teacher-card ul{color:var(--ink-2);gap:8px;margin:0 0 12px;padding-left:20px;display:grid}.teacher-card a:not(.btn){color:var(--accent)}@media (max-width:1180px){.lesson-brand small{display:none}.lesson-nav__teacher{display:none!important}}@media (max-width:960px){.lesson-head{flex-wrap:wrap;row-gap:8px;height:auto;padding-top:10px;padding-bottom:10px}.lesson-nav{order:3;width:100%;margin:0}.lesson-head__tools{margin-left:auto}:root{--head-h:118px}.ov-hero{min-height:auto;padding-top:calc(var(--head-h) + 6px);grid-template-columns:1fr}.ov-model{order:-1;height:60svh}.ov-steps{grid-template-columns:1fr 1fr}.ov-goals ol,.warmup-grid,.apply-grid,.teacher-grid{grid-template-columns:1fr}.puzzle{width:100%}.stage{flex-direction:column;height:auto;min-height:0;display:flex}.stage-view{height:62svh;position:relative}.stage-panel{max-height:none;margin:12px 16px 0;position:static;width:auto!important}.explore-systems{order:2}.viewer-views{top:auto;bottom:60px}.result-box--row{grid-template-columns:1fr}}@media (max-width:560px){.lesson-main{padding-top:18px}.ov-steps{grid-template-columns:1fr}.keyword-cells span{width:32px;height:40px;font-size:1.05rem}.lesson-nav a{padding:7px 10px}}@media print{:root{--ink:#142527;--ink-2:#44585a;--line:#dbe5e3;--surface:#fff}body{color:#142527;background:#fff}.lesson-head,.step-pager,.section-head--row .btn{display:none!important}.card{box-shadow:none;-webkit-backdrop-filter:none;backdrop-filter:none}}