:root{--navy:#102247;--ink:#17284b;--muted:#687992;--line:#dce5f1;--blue:#1468e8;--blue-deep:#0a4fb4;--blue-light:#eef5ff;--page:#f5f8fc;--white:#fff;--teal:#008f88;--teal-bg:#e8f8f4;--gold:#f4bb45;--radius:18px;--shadow:0 12px 40px rgba(13,41,84,.075)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--page);color:var(--ink);font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.5}button,input{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #f3ba45;outline-offset:3px}a{color:inherit;text-decoration:none}.wrap{max-width:1260px;margin:0 auto;padding:0 25px}.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:30}.header-inner{display:flex;align-items:center;gap:24px;min-height:80px}.brand{display:flex;align-items:center;gap:13px;min-width:285px}.brand-mark{display:grid;place-items:center;height:42px;width:42px;background:#eaf3ff;border:1px solid #cfe2ff;border-radius:13px;color:#095bbb}.brand-name{font-size:20px;font-weight:850;letter-spacing:-.75px;color:var(--navy);line-height:1.1}.brand-sub{font-size:11px;color:#58708f;font-weight:650;letter-spacing:.05px;margin-top:4px}.main-nav{display:flex;align-items:center;gap:6px;margin-left:auto}.main-nav button{border:0;background:none;color:#52647c;font-size:14px;font-weight:650;padding:10px 13px;border-radius:9px}.main-nav button:hover,.main-nav button.active{background:#edf5ff;color:#114eac}.header-progress{display:flex;align-items:center;gap:8px;font-size:12px;font-weight:750;color:#28726d;background:#ecfaf5;border:1px solid #d1eee8;border-radius:99px;padding:9px 12px;white-space:nowrap}.mobile-menu{display:none}.hero{margin:28px 0 28px;display:grid;grid-template-columns:1.02fr .98fr;overflow:hidden;background:#10264c;border-radius:24px;box-shadow:var(--shadow);min-height:342px;position:relative}.hero-copy{padding:43px 42px;position:relative;z-index:2}.eyebrow{font-weight:850;text-transform:uppercase;font-size:11px;letter-spacing:2.4px;color:#84c5ff}.hero h1{font-size:clamp(32px,3.6vw,48px);line-height:1.12;letter-spacing:-1.9px;color:white;max-width:530px;margin:16px 0}.hero h1 em{font-style:normal;color:#7dc2ff}.hero p{color:#d3e2f5;max-width:435px;margin:0 0 24px;font-size:16px}.hero-actions{display:flex;flex-wrap:wrap;gap:11px}.btn{border-radius:10px;padding:11px 17px;font-size:13px;font-weight:800;display:inline-flex;align-items:center;justify-content:center;gap:9px;border:1px solid transparent;white-space:nowrap}.btn-primary{background:var(--blue);color:#fff;border-color:var(--blue)}.btn-primary:hover{background:var(--blue-deep)}.btn-hero{background:white;color:#0e438e}.btn-hero:hover{background:#e6f3ff}.btn-ghost{background:transparent;border-color:#59749d;color:#fff}.btn-ghost:hover{background:#1c3764}.hero-art{position:relative;overflow:hidden;background:radial-gradient(circle at 80% 25%,#315f98 0%,transparent 50%),linear-gradient(140deg,#12305c,#1c4477)}.art-grid{position:absolute;inset:0;background-image:linear-gradient(90deg,rgba(255,255,255,.04) 1px,transparent 1px),linear-gradient(rgba(255,255,255,.04) 1px,transparent 1px);background-size:28px 28px;transform:rotate(-9deg) scale(1.3)}.art-notebook{position:absolute;width:330px;height:263px;left:11%;top:61px;border-radius:13px;border:1px solid #d3ddeb;background:repeating-linear-gradient(0deg,#fff 0px,#fff 27px,#e8eff7 28px);box-shadow:0 20px 55px rgba(0,0,0,.23);transform:rotate(-9deg);padding:30px 30px;color:#1b335b}.art-notebook:before{content:"";position:absolute;left:19px;top:0;bottom:0;border-left:2px solid #eaa5a5;opacity:.45}.notebook-top{font-size:11px;font-weight:800;color:#4e6991;letter-spacing:1px}.notebook-equation{font-size:32px;letter-spacing:-.5px;font-weight:750;margin-top:22px}.notebook-steps{font-size:12px;margin-top:14px;font-weight:750}.step-floating{position:absolute;right:7%;top:47px;background:#fff;padding:16px 19px;border:1px solid #d9e6f4;box-shadow:0 13px 35px rgba(0,18,45,.28);border-radius:14px;width:224px;transform:rotate(6deg)}.step-floating .pchip{color:#1472d0;background:#e9f4ff;padding:4px 7px;border-radius:5px;font-size:10px;font-weight:800}.step-floating h4{font-size:15px;line-height:1.35;margin:13px 0 10px}.step-floating .expr{font-weight:850;font-size:24px;color:#102c5a}.step-floating small{display:block;color:#687992;margin-top:6px}.art-note{position:absolute;right:10%;bottom:26px;background:#d9f8ed;color:#084f51;padding:13px 18px;font-weight:800;border-radius:10px;transform:rotate(-6deg);font-size:13px;box-shadow:0 13px 25px rgba(0,18,45,.19)}.section-heading{display:flex;align-items:end;justify-content:space-between;gap:16px;margin:0 0 16px}.section-heading h2{font-size:23px;line-height:1.25;margin:0;font-weight:850;letter-spacing:-.7px;color:var(--navy)}.section-heading p{color:var(--muted);font-size:13px;margin:5px 0 0}.section-note{font-size:12px;color:var(--muted);font-weight:650}.week-strip{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-bottom:30px}.week-card{display:flex;align-items:center;justify-content:space-between;gap:12px;text-align:left;background:white;border-radius:14px;padding:16px 18px;border:1px solid var(--line);box-shadow:0 4px 16px rgba(13,41,84,.03);min-height:89px}.week-card[disabled]{opacity:.62;cursor:default}.week-card.current{border:2px solid #3a86f5;background:linear-gradient(115deg,#f3f8ff,#eaf4ff)}.week-title{font-weight:850;font-size:15px;color:var(--navy)}.week-desc{font-size:12px;color:#73839a;margin-top:4px}.badge{font-size:10px;font-weight:800;padding:6px 8px;border-radius:8px;background:#e5f0ff;color:#0d58bd}.badge.soon{background:#f0f2f6;color:#7d8796}.topic-section{margin:0 0 30px}.topic-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:10px}.topic-tile{display:flex;align-items:center;gap:12px;text-align:left;background:white;border:1px solid var(--line);border-radius:12px;padding:12px 15px;font-size:13px;font-weight:750;color:#243d62;min-height:62px}.topic-tile:hover,.topic-tile.selected{border-color:#74a7ef;background:#f0f7ff}.topic-icon{width:36px;height:36px;display:grid;place-items:center;border-radius:9px;background:#ecf3ff;color:#1468e8;font-size:17px;font-weight:900}.topic-tile:nth-child(2n) .topic-icon{background:#e9f8f5;color:#00837f}.topic-tile:nth-child(3n) .topic-icon{background:#fff5e9;color:#bb7726}.dashboard{margin-top:12px;scroll-margin-top:100px}.dashboard-head{display:flex;align-items:start;justify-content:space-between;gap:20px;margin:0 0 16px}.dashboard-head h2{margin:0;font-size:29px;font-weight:850;letter-spacing:-1px;color:var(--navy)}.dashboard-head p{margin:5px 0;color:var(--muted);font-size:13px}.dashboard-controls{display:flex;align-items:center;gap:9px;flex-wrap:wrap}.search{background:#fff;border:1px solid var(--line);border-radius:10px;display:flex;align-items:center;gap:8px;padding:0 12px;color:#7b8b9e;min-width:185px}.search input{border:0;outline:none;width:155px;max-width:100%;padding:11px 0;font-size:13px;color:var(--ink);background:none}.search:focus-within{border-color:#3f83e3}.progress-bar-wrap{margin:8px 0 19px;background:white;border:1px solid var(--line);border-radius:12px;padding:11px 14px;display:flex;align-items:center;gap:14px}.progress-bar{height:8px;flex:1;max-width:270px;border-radius:99px;overflow:hidden;background:#e9eff8}.progress-bar > div{height:100%;width:0;background:#1c9f92;border-radius:inherit;transition:width .2s}.progress-description{font-size:12px;color:#667b93;font-weight:700}.board-layout{display:grid;grid-template-columns:minmax(0,1.02fr) minmax(0,.98fr);align-items:start;gap:18px}.panel{background:#fff;border:1px solid var(--line);border-radius:18px;box-shadow:0 8px 32px rgba(13,41,84,.045)}.list-panel{padding:20px}.day-tabs{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;margin-bottom:18px}.day-tab{background:#f3f6fb;border:1px solid #e1e8f2;border-radius:11px;padding:12px 5px;font-size:13px;font-weight:800;color:#526783}.day-tab small{display:block;font-size:10px;font-weight:600;margin-top:3px;color:#8a99ab}.day-tab.active{background:#153b73;border-color:#153b73;color:white}.day-tab.active small{color:#d3e6ff}.panel-label{font-size:12px;font-weight:850;letter-spacing:.5px;color:#71849c;text-transform:uppercase;margin-bottom:7px}.lesson-row{width:100%;display:flex;align-items:center;gap:12px;text-align:left;border:1px solid #e4eaf2;background:white;border-radius:11px;padding:13px 11px;margin-top:9px;min-height:78px}.lesson-row:hover{border-color:#98bdea;background:#f6faff}.lesson-row.selected{border-color:#3b87e9;background:#f1f7ff;box-shadow:inset 3px 0 0 #2877e5}.number-dot{flex:0 0 34px;height:34px;border-radius:11px;display:grid;place-items:center;background:#e7f0ff;color:#155dbb;font-size:13px;font-weight:900}.row-body{flex:1;min-width:0}.row-title{font-size:13px;font-weight:800;color:#203b62;line-height:1.4}.row-meta{display:flex;align-items:center;gap:6px;flex-wrap:wrap;margin-top:6px}.tag{background:#eaf1fa;color:#50739c;border-radius:6px;font-size:10px;font-weight:700;padding:4px 7px}.status{font-size:10px;font-weight:800}.status.got{color:#168276}.status.help{color:#b16b22}.row-arrow{font-size:21px;color:#9baabd}.lesson-panel{padding:0;overflow:hidden;position:relative;scroll-margin-top:98px}.lesson-header{padding:20px 22px 16px;border-bottom:1px solid #e6edf5}.lesson-kicker{font-size:11px;font-weight:800;letter-spacing:.5px;text-transform:uppercase;color:#56749f;display:flex;justify-content:space-between;align-items:center;gap:8px}.lesson-header h3{font-size:24px;line-height:1.22;letter-spacing:-.6px;margin:10px 0;color:#132a50}.lesson-tabs{display:flex;gap:5px;overflow-x:auto;border-bottom:1px solid #e7edf5;padding:0 17px}.lesson-tabs button{padding:12px 10px;font-size:12px;border:0;border-bottom:3px solid transparent;background:none;color:#70809a;font-weight:800;white-space:nowrap}.lesson-tabs button.active{border-color:#1468e8;color:#0d57bb}.lesson-content{padding:22px}.problem-box{background:#f0f6ff;border:1px solid #dfebff;padding:16px;border-radius:11px;margin-bottom:16px}.micro-label{font-size:10px;color:#5579ac;font-weight:900;letter-spacing:1.2px;text-transform:uppercase}.problem-box p{margin:7px 0 0;font-size:16px;font-weight:750;color:#203b61;white-space:pre-line}.callout{border:1px solid #f0e5c7;background:#fffaf0;border-radius:11px;padding:15px;margin-bottom:15px}.callout h4{margin:0 0 4px;font-size:13px;color:#805925}.callout p{margin:0;font-size:13px;color:#685e4d}.step-card{border:1px solid #e2e9f3;background:#fff;border-radius:11px;padding:14px;margin:11px 0}.step-top{display:flex;gap:10px;align-items:flex-start}.step-num{height:27px;width:27px;flex:0 0 27px;display:grid;place-items:center;background:#e6f0ff;color:#0e62cb;border-radius:9px;font-weight:850;font-size:12px}.step-card p{margin:3px 0;color:#233959;font-size:13px;line-height:1.65}.step-card pre,.paper{white-space:pre;overflow-x:auto;display:block;background:#fafcff;border:1px solid #e2eaf5;color:#17365d;padding:12px;border-radius:8px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:15px;line-height:1.55;margin:10px 0 0}.step-controls{display:flex;flex-wrap:wrap;gap:10px;margin-top:15px}.answer-box{border:1px solid #b5e4d7;background:#edfbf5;border-radius:12px;padding:14px 16px;margin-top:15px}.answer-box .label{font-size:11px;font-weight:900;color:#15735f;text-transform:uppercase;letter-spacing:.8px}.answer-box .answer{font-size:19px;font-weight:850;color:#124d49;margin-top:6px;white-space:pre-line;line-height:1.55}.blocked-answer{border:1px dashed #afc2d9;background:#f6f9fc;border-radius:10px;padding:17px;font-size:12px;color:#627995;margin:14px 0;text-align:center}.fraction-visual{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin:13px 0 4px;padding:14px;background:#f8fbff;border:1px solid #e5edf6;border-radius:10px}.fracbar{display:grid;grid-template-columns:repeat(6,24px);gap:2px}.fracbar span{height:33px;border:1px solid #a7bbd4;border-radius:2px;background:#fff}.fracbar span.fill{background:#64a5f5;border-color:#4385d7}.fracbar.green span.fill{background:#67bfb3;border-color:#369a90}.fracnote{font-weight:750;font-size:11px;color:#4e6786}.dotplot{display:flex;align-items:end;gap:10px;justify-content:space-around;padding:18px 10px 6px;background:#f8fbff;border-radius:10px;margin:13px 0}.dot-col{flex:1;max-width:35px;text-align:center}.dot-stack{height:140px;display:flex;flex-direction:column-reverse;align-items:center;gap:3px;justify-content:flex-start;border-bottom:2px solid #98abc5;padding-bottom:5px}.dot{height:12px;width:12px;flex:0 0 12px;border-radius:50%;background:#2986de}.dot-label{font-size:12px;font-weight:850;margin-top:7px}.helper{color:#6c7e96;font-size:12px;margin-top:9px}.status-actions{display:flex;gap:9px;flex-wrap:wrap;margin-top:19px;border-top:1px solid #e8edf5;padding-top:17px}.btn-soft{background:#eef5ff;color:#145db9;border-color:#cfe1fb}.btn-soft:hover{background:#e4efff}.btn-help{background:#fff7ed;color:#9b651c;border-color:#f4dfbd}.btn-help:hover{background:#fff1de}.btn-done{background:#e9f8f3;color:#147a70;border-color:#bce6d9}.btn-done:hover{background:#ddf3ec}.mini-feature{padding:16px;border:1px solid #e0e8f2;border-radius:12px;margin-bottom:12px}.mini-feature h4{font-size:14px;margin:0 0 7px;color:#17365d}.mini-feature p{font-size:13px;color:#51667f;margin:0;line-height:1.6}.mini-feature ul{padding-left:18px;margin:9px 0 0;color:#546b85;font-size:13px}.small-link{border:0;background:none;color:#1162ce;font-size:12px;font-weight:800;padding:5px 0;text-decoration:underline}.try-card{background:#f7fbff;border:1px solid #dbe9fc;padding:18px;border-radius:12px}.try-prompt{font-weight:800;color:#1d3e64;font-size:17px;margin:10px 0 14px}.try-card input{border:1px solid #becfe5;padding:11px;border-radius:9px;width:100%;margin-bottom:10px}.practice-reveal{margin:13px 0 0;padding:12px;background:#e8f7f2;border:1px solid #bce9d8;border-radius:9px;font-size:14px;font-weight:800;color:#236b5c}.foot{padding:40px 0 50px;text-align:center;color:#7e8ca0;font-size:12px}.foot strong{color:#334f73}.no-results{text-align:center;padding:24px;color:#7388a3;font-size:13px}.topic-filter-state{display:none;align-items:center;justify-content:space-between;gap:8px;border:1px solid #cae0fc;background:#f1f7ff;padding:10px 12px;border-radius:10px;margin-bottom:12px;font-size:12px;color:#215a9f;font-weight:750}.topic-filter-state.visible{display:flex}.topic-filter-state button{border:0;background:none;color:#0e5fc5;font-weight:800}.empty-state{padding:22px;color:#7d8da1;font-size:13px;text-align:center}.mobile-help{display:none}@media(max-width:1070px){.header-inner{gap:14px}.brand{min-width:238px}.brand-name{font-size:18px}.main-nav button{padding:8px}.hero-copy{padding:37px 28px}.step-floating{right:3%;width:202px}.board-layout{grid-template-columns:1fr 1fr}.topic-grid{grid-template-columns:repeat(4,1fr)}}@media(max-width:860px){.site-header{position:relative}.main-nav{display:none}.header-progress{margin-left:auto}.hero{grid-template-columns:1fr}.hero-art{height:250px}.art-notebook{top:25px;left:18%}.step-floating{top:18px;right:16%}.art-note{right:10%;bottom:15px}.topic-grid{grid-template-columns:repeat(2,1fr)}.board-layout{grid-template-columns:1fr}.lesson-panel{margin-top:0}.dashboard-head{flex-wrap:wrap}.mobile-help{display:block;font-size:12px;color:#6b809c;margin-bottom:15px}}@media(max-width:560px){.wrap{padding:0 14px}.header-inner{min-height:72px}.brand{min-width:0}.brand-mark{height:36px;width:36px}.brand-name{font-size:16px}.brand-sub{font-size:9px}.header-progress{font-size:10px;padding:7px}.hero{margin-top:14px;border-radius:17px;min-height:0}.hero-copy{padding:29px 23px}.hero h1{font-size:33px;margin:11px 0}.hero p{font-size:14px}.hero-art{height:218px}.art-notebook{left:6%;top:12px;width:265px;height:230px;padding:28px}.notebook-equation{font-size:24px}.step-floating{right:3%;top:13px;width:172px;padding:12px}.step-floating h4{font-size:12px}.step-floating .expr{font-size:19px}.art-note{bottom:12px;right:10px}.week-strip{grid-template-columns:1fr;gap:8px}.week-card{min-height:66px}.topic-grid{grid-template-columns:repeat(2,1fr);gap:8px}.topic-tile{font-size:11px;padding:10px;gap:7px}.topic-icon{height:30px;width:30px;flex:0 0 30px}.dashboard-head h2{font-size:26px}.dashboard-controls,.search{width:100%}.search input{width:100%}.list-panel{padding:11px}.day-tabs{gap:4px}.day-tab{font-size:11px;padding:10px 2px}.lesson-header{padding:17px}.lesson-header h3{font-size:21px}.lesson-content{padding:15px}.lesson-row{padding:11px 9px}.row-title{font-size:12px}.row-arrow{font-size:16px}.progress-bar-wrap{flex-wrap:wrap}.fracbar{grid-template-columns:repeat(6,18px)}.fracbar span{height:30px}.step-floating small{font-size:10px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
/* Instructional visuals: clean geometry and generous type. */
.visual-box{margin:17px 0 20px;background:#f7faff;border:1px solid #d8e6f5;border-radius:14px;padding:18px;overflow:hidden}.visual-box figcaption{font-size:14px;font-weight:800;margin-bottom:16px;color:#264d78}.visual-note{font-size:13px;color:#516b89;margin:13px 0 0;line-height:1.6}.equation{font-size:clamp(18px,2vw,24px);font-weight:750;text-align:center;margin:16px 0;color:#17365d;overflow-wrap:anywhere}.number-chips{display:flex;flex-wrap:wrap;gap:7px;margin:9px 0 16px}.number-chip{border:1px solid #c8d8eb;background:#fff;border-radius:8px;padding:7px 11px;min-width:33px;text-align:center;font-weight:700}.number-chip.highlight{background:#d9f4ec;border:2px solid #008478;color:#005f55}.bar-label{font-size:12px;color:#516b89;margin:10px 0 6px}.model-bar{display:grid;grid-template-columns:repeat(var(--parts),1fr);max-width:100%;height:44px;border:1px solid #698fb5;margin-bottom:14px;background:white}.model-bar>span{border-right:1px solid #9db6ce}.model-bar>span:last-child{border-right:0}.model-bar .blue,.hundred-model .blue{background:#5c9feb}.model-bar .teal{background:#50b6a5}.group-model{display:flex;gap:5px;margin-top:22px}.group-model>span:first-child{flex:3;background:#d9ecff}.group-model>span:last-child{flex:1;background:#d9f4ec}.group-model>span{padding:11px 5px;border-top:3px solid #1768ca;text-align:center;font-size:12px;font-weight:750}.group-model small{font-weight:400}.shape-set{display:flex;justify-content:center;flex-wrap:wrap;gap:13px;padding:15px}.shape-square,.shape-circle{height:30px;width:30px;display:inline-block;background:#397cdc}.shape-circle{background:#0b9389;border-radius:50%}.translation{display:flex;justify-content:center;gap:10px}.translation>span{padding:10px 15px;background:white;border:1px solid #cee0f3;border-radius:9px}.math-group{background:#d9f4ec;border-radius:7px;padding:4px}.math-paper{background-color:#fff;background-image:linear-gradient(#e3ecf5 1px,transparent 1px);background-size:100% 42px;max-width:340px;margin:0 auto;padding:15px 25px 20px;border:1px solid #d7e2ef;border-radius:9px}.paper-label{font-size:11px;letter-spacing:.4px;color:#667b96;margin-bottom:10px}.digit-row{display:grid;grid-template-columns:repeat(8,minmax(0,1fr));font-family:ui-monospace,monospace;font-size:clamp(20px,3vw,28px);text-align:center;height:42px;align-items:center;font-variant-numeric:tabular-nums}.digit-row .digit-focus{background:#daf3e8;border-radius:5px;color:#006758}.digit-row.carry-row{height:27px;font-size:16px;color:#b04d18}.math-rule{height:2px;background:#17365d;margin:5px 0}.regroup-note{color:#ad4f20;font-size:13px;text-align:center;margin-bottom:14px}.math-svg{width:100%;max-width:370px;display:block;margin:auto;max-height:290px}.model-svg{width:100%;max-width:430px;display:block;margin:auto}.rate-model{display:flex;gap:7px}.rate-model>div{flex:1;text-align:center;background:#deecff;border:1px solid #accdf1;border-radius:8px;padding:13px 5px}.rate-model span{display:block;font-size:12px;color:#526b88}.rate-model strong{display:block;font-size:17px;margin-top:7px}.percent-bar{height:38px;border:1px solid #7d9abd;background:white}.percent-bar>div{height:100%;background:#4e93e1}.hundred-model{display:grid;grid-template-columns:repeat(10,1fr);gap:3px;max-width:255px;margin:15px auto}.hundred-model>span{aspect-ratio:1;border:1px solid #93b0d1;background:#fff}.tape-total{text-align:center;border-top:2px solid #698db6;padding:7px;margin-top:20px}.tape{display:flex;height:62px}.tape>span{display:grid;place-items:center;border:1px solid #6b98cf;background:#b9d8fe;font-size:22px;font-weight:800}.tape>span.unknown{background:#a4e2d4;border-color:#429a89}.table-pair{display:grid;grid-template-columns:1fr 1fr;gap:16px}.model-table{border-collapse:collapse;width:100%;margin:8px 0;font-variant-numeric:tabular-nums;font-size:14px;text-align:center;background:white}.model-table td,.model-table th{border:1px solid #cbdbec;padding:8px}.model-table th{background:#e1edfc}.substitution-grid{display:grid;gap:8px}.substitution-grid>div{border:1px solid #d3e2f0;border-radius:8px;background:white}.substitution-grid .equation{font-size:19px;margin:10px}.area-model{display:flex;margin-left:30px;position:relative;min-height:135px;border:2px solid #3579b8}.area-height{position:absolute;left:-27px;top:45%;font-weight:850}.area-part{background:#d5e7ff;flex:3;display:grid;place-items:center;padding:15px;border-right:2px solid #3579b8}.area-part.teal{background:#beeadf;flex:4;border-right:0}.area-part span{font-size:14px}.area-part strong{font-size:20px}.median-marker{text-align:center;font-size:14px}.median-marker strong{padding:8px;background:#d5f3e7;border-radius:6px}.median-dot{background:#f6bb44;outline:2px solid #8f580b;outline-offset:2px}.step-meter{display:flex;justify-content:space-between;gap:15px;font-size:13px;font-weight:750;color:#557494;margin:17px 0 7px}.step-track{height:5px;border-radius:8px;overflow:hidden;background:#e0eaf5}.step-track>span{display:block;height:100%;background:#008478}.step-card p{font-size:15px;line-height:1.7}.problem-box p{font-size:17px}.lesson-header h3{font-size:25px}.lesson-tabs button{font-size:13px}.btn{font-size:14px;min-height:42px}.btn:disabled{opacity:.5;cursor:default}.row-title{font-size:14px}.related{margin-top:21px;border-top:1px solid #e4eaf2;padding-top:10px}.related h4{margin:8px 0;font-size:13px}.related button{display:block;text-align:left;line-height:1.5;margin-top:3px}.filter-active{background:#d4e9ff;border-color:#488ee9}.try-card textarea{font:inherit;width:100%;resize:vertical;border:1px solid #b9cde5;border-radius:9px;padding:11px;margin:8px 0 13px;background:white;color:#17365d}.try-card textarea:focus-visible{outline:3px solid #f3ba45}.day-tabs:has(>button:only-child){grid-template-columns:1fr}.status-actions button[aria-pressed=true]{outline:2px solid currentColor;outline-offset:1px}.week-strip .week-card.current{outline:1px solid #90bdf7}.topic-grid{grid-template-columns:repeat(4,1fr)}
@media(min-width:1000px){.board-layout{grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr)}.hero-art{min-height:330px}}
@media(max-width:860px){.topic-grid{grid-template-columns:repeat(2,1fr)}.main-nav{display:flex;order:3;width:100%;justify-content:center;margin:0;padding-bottom:8px}.header-inner{flex-wrap:wrap;padding-top:13px;gap:10px}.hero-art{height:240px}.board-layout{grid-template-columns:1fr}}
@media(max-width:560px){.hero-copy{padding:28px 24px}.hero h1{font-size:35px}.hero-art{height:220px}.lesson-content{padding:16px}.visual-box{padding:14px}.table-pair{gap:8px}.row-title{font-size:14px}.brand-sub{font-size:10px;max-width:210px}.header-progress{font-size:10px}.rate-model strong{font-size:14px}.group-model>span{font-size:11px}.hero-actions .btn{font-size:13px}.translation>span{font-size:14px;padding:8px}.area-part strong{font-size:17px}}

/* Welcome link in the lesson dashboard navigation. */
.main-nav a{padding:10px 13px;border-radius:9px;font-size:14px;font-weight:650;color:#52647c}.main-nav a:hover{background:#edf5ff;color:#114eac}