/* Bilingual Teaching Hub AI – Colorful Academic Library visual refresh.
   Built on top of the existing lesson engine; no SGK source data is modified. */
:root{--navy:#173c64;--navy-light:#244d77;--paper:#f6f8fd;--ink:#19314c;--muted:#687e96;--line:#e3eaf4;--line-strong:#cdd9e9;--teal:#0b8c8d;--white:#fff;--shadow:0 12px 32px rgba(30,57,91,.055);--radius:17px}
body{font-family:system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;background:#f7f9fd;color:#1b344d;letter-spacing:-.005em}
.top-line{height:5px;background:linear-gradient(90deg,#3c84ef 0 25%,#8771ce 25% 50%,#e8a349 50% 75%,#33a679 75% 100%)}
.shell{grid-template-columns:283px minmax(0,1fr);min-height:calc(100vh - 5px);max-width:1920px}.sidebar{background:#fff;padding:23px 15px 15px;border-color:#e7edf5;box-shadow:1px 0 14px #143b5a05}
.brand{padding:0 5px 20px;gap:12px}.brand-emblem{border-radius:15px;width:47px;height:47px;background:linear-gradient(145deg,#163a65,#23758e);box-shadow:0 10px 22px #18517f24}.brand b{font-size:10px;letter-spacing:.15em;color:#416b93}.brand strong{font-size:20px;letter-spacing:-.06em}.brand strong span{color:#129a98}.brand small{font-size:8px;letter-spacing:.10em;color:#768aa3;margin-top:5px}
.section-kicker,.field-label{font-size:10px;color:#8495ad}.level-tag{background:#e9f1fb;color:#245889;border:1px solid #dce9f8}.subject-grid{gap:8px;margin-bottom:19px}.subject-btn{border-radius:12px;border-color:#e4ebf5;background:#fbfcff;padding:12px;min-height:77px;box-shadow:none}.subject-btn .subject-symbol{font-size:21px;width:30px;height:30px;box-shadow:none;border:1px solid #e9edf4}.subject-btn strong{font-size:12px}.subject-btn.active{box-shadow:0 5px 15px rgba(33,63,101,.07);border-width:2px}.chapter-select,.search-wrap{border-radius:12px}.lesson-link{border-radius:11px;padding:12px 9px}.lesson-link strong{font-size:12px}.lesson-link.active{border-left:3px solid var(--subject-color,#0a9a91);background:#f0f8fa}.lesson-num{border-radius:8px}
.header-bar{height:72px;background:rgba(255,255,255,.97);padding:0 clamp(20px,3vw,48px);gap:17px}.breadcrumbs{font-size:9.6px;color:#8493a4;letter-spacing:.075em;white-space:nowrap}.header-links{display:flex;align-items:center;gap:4px;margin-left:auto}.header-links button{border:0;background:transparent;padding:10px 12px;border-radius:10px;color:#526782;font-size:12px;font-weight:750;white-space:nowrap}.header-links button:hover{background:#ecf4fb;color:#1c577f}.header-controls{gap:8px}.source-chip{background:#f2f6fc;border:1px solid #e4ebf5;font-size:10px;padding:7px 10px}.icon-button{border-radius:11px}
main{padding:28px clamp(22px,3vw,48px) 66px;max-width:1580px}.site-footer{background:#fff;font-size:10.5px;color:#7d8da0}.new-home{display:grid;gap:0}.hero-campus.academic-hero{background:linear-gradient(117deg,#143759 0%,#1b527a 57%,#216d81 100%);border:1px solid #154968;min-height:355px;border-radius:25px;padding:43px 40px;color:#fff;grid-template-columns:minmax(0,1.25fr) minmax(300px,.85fr);margin-bottom:22px;box-shadow:0 22px 45px rgba(17,66,94,.16)}.academic-hero:before{width:370px;height:370px;right:-160px;top:-210px;border:1px solid #ffffff22;background:transparent}.academic-hero:after{content:"";position:absolute;width:450px;height:450px;border:1px solid #ffffff10;border-radius:50%;right:0;bottom:-360px;pointer-events:none}.academic-hero .hero-text{align-self:center;z-index:2}.hero-eyebrow{display:inline-flex;align-items:center;gap:9px;color:#b5e4df;font-size:10px;font-weight:850;letter-spacing:.15em}.pulse-dot{width:7px;height:7px;border-radius:100%;background:#6fe3b4;box-shadow:0 0 0 4px #6fe3b424}.academic-hero h1{color:#fff;font-size:clamp(33px,3.7vw,56px);letter-spacing:-.055em;margin:16px 0 15px;line-height:1.17}.academic-hero h1 em{font-style:normal;color:#91ece0}.academic-hero p{color:#dbeaf5;line-height:1.76;font-size:13.5px;max-width:640px}.academic-hero p b{color:#fff}.academic-hero .btn.primary{background:#fff;border-color:#fff;color:#174361;font-size:12.5px;padding:12px 17px}.academic-hero .hero-outline{background:#ffffff12;border-color:#ffffff60;color:#fff;padding:12px 17px}.academic-hero .hero-actions{margin-top:24px}.hero-credentials{display:flex;gap:23px;flex-wrap:wrap;margin-top:30px;color:#bcd7e8;font-size:11px}.hero-credentials strong{font-size:16px;color:#fff;margin-right:4px}.hero-credentials span+span{border-left:1px solid #ffffff34;padding-left:21px}.academic-hero .hero-illustration{min-height:295px;overflow:visible;z-index:1}.hero-academic-art{position:relative;width:100%;height:300px;max-width:425px;margin:auto}.art-main{position:absolute;inset:26px 45px 22px 38px;background:linear-gradient(155deg,#ffffff,#ebf6ff);border:7px solid #ffffff25;border-radius:23px;box-shadow:0 18px 43px #06294365;transform:rotate(-3deg);display:flex;align-items:center;justify-content:center;overflow:hidden}.art-main .subject-art-svg{width:78%;max-height:182px}.art-badge{position:absolute;top:12px;left:17px;color:#2d6b8a;font-size:9px;font-weight:900;letter-spacing:.1em}.art-badge span{color:#e1a657}.art-formula{position:absolute;bottom:13px;left:17px;color:#47718d;font-size:9px;font-weight:850}.art-orbit{position:absolute;border-radius:16px;background:#fff;box-shadow:0 12px 25px #082e4b44;border:5px solid #ffffffb2;width:110px;height:90px;display:grid;place-items:center}.art-orbit svg{width:100%;height:100%}.art-orbit-phy{right:-4px;top:1px;transform:rotate(11deg)}.art-orbit-chem{right:0;bottom:5px;transform:rotate(7deg);width:116px}.art-orbit-bio{left:-5px;bottom:-8px;transform:rotate(-9deg);width:118px}
.home-search-section{background:#fff;border:1px solid #e5ecf5;border-radius:18px;padding:18px 22px;margin-bottom:36px;box-shadow:0 7px 20px #193d6008;display:grid;grid-template-columns:minmax(180px,290px) minmax(0,1fr);align-items:start;gap:12px 22px}.home-search-head{display:flex;align-items:center;gap:12px}.search-bubble{width:42px;height:42px;border-radius:12px;background:#eaf6f5;color:#168a87;font-size:25px;display:grid;place-items:center}.home-search-head strong{display:block;font-size:13.5px;color:#234362}.home-search-head small{display:block;font-size:11px;color:#8293a6;line-height:1.45}.home-search-input{background:#f7f9fd;display:flex;align-items:center;gap:13px;min-height:50px;border:1px solid #dce6f2;border-radius:12px;padding:0 15px;color:#7494b2}.home-search-input:focus-within{border-color:#2a9796;box-shadow:0 0 0 3px #d8f3ef}.home-search-input span{font-size:27px;line-height:1}.home-search-input input{width:100%;padding:12px 0;border:0;background:transparent;outline:none;color:#25435e;font-size:13px}.home-search-results{grid-column:2;display:grid;gap:5px}.search-helper{font-size:10.5px;color:#8495a7}.search-helper b{font-weight:600;color:#4e7498}.home-result{display:flex;align-items:center;gap:11px;text-align:left;border:1px solid #e9eff5;background:#fff;border-radius:9px;padding:9px;width:100%}.home-result:hover{background:#f0f7fb}.home-result-sub{width:30px;height:30px;border-radius:8px;background:var(--subject-bg);color:var(--subject-color);display:grid;place-items:center;font-size:19px}.home-result strong{font-size:12px;display:block;color:#244a6a}.home-result small{display:block;color:#7e92a7;font-size:10px}.result-arrow{margin-left:auto;color:#6685a0}
.home-section-heading{margin:0 0 20px;align-items:center}.home-section-heading .eyebrow{font-size:10.5px;color:#188589}.home-section-heading h2{font-size:clamp(22px,2.1vw,30px);letter-spacing:-.045em;margin:4px 0}.section-desc{font-size:12.5px;color:#8492a3}.academic-counter{font-size:11px;font-weight:800;background:#fff;padding:10px 13px;color:#5c7490;border-radius:9px;border:1px solid #e0e8f2}
.subject-cards.academic-subjects{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:15px;margin-bottom:41px}.academic-subject-card{padding:0;display:flex;flex-direction:column;text-align:left;overflow:hidden;background:#fff;border:1px solid #e2eaf2;border-radius:20px;box-shadow:0 8px 22px rgba(24,53,83,.055);position:relative;min-height:313px;transition:transform .22s ease,box-shadow .22s ease}.academic-subject-card:hover{transform:translateY(-5px);box-shadow:0 20px 35px rgba(24,53,83,.13);border-color:var(--subject-color)}.academic-subject-card .subject-card-top{display:flex;align-items:center;justify-content:space-between;padding:16px 18px 0;width:100%;position:absolute;z-index:2}.subject-no{font-size:9px;font-weight:800;color:var(--subject-color);letter-spacing:.11em}.subject-mark{font-size:22px;color:var(--subject-color)}.subject-art-scene{display:flex;align-items:center;justify-content:center;width:100%;height:165px;position:relative;overflow:hidden}.subject-art-scene:after{content:"";position:absolute;inset:auto -6% -40px;width:112%;height:66px;background:#fff;border-radius:50% 50% 0 0;pointer-events:none}.subject-art-scene svg{width:86%;height:145px;margin-top:22px;filter:drop-shadow(0 6px 9px #1d416b12)}.academic-math .subject-art-scene{background:linear-gradient(125deg,#d9eaff,#f1f7ff)}.academic-physics .subject-art-scene{background:linear-gradient(125deg,#e3dffc,#f5f2ff)}.academic-chemistry .subject-art-scene{background:linear-gradient(125deg,#ffedd4,#fff7e9)}.academic-biology .subject-art-scene{background:linear-gradient(125deg,#dbf2e4,#f0fcf7)}.subject-card-details{padding:14px 18px 18px;display:flex;flex-direction:column;flex:1;position:relative;z-index:2}.subject-card-details>strong{font-size:21px;font-weight:850;color:#213c58;letter-spacing:-.04em;line-height:1.18}.subject-card-details>strong small{font-size:13px;color:var(--subject-color)}.subject-en{font-size:10px;font-weight:800;letter-spacing:.12em;color:var(--subject-color);margin-top:6px}.subject-description{font-size:11.5px;color:#6e849a;line-height:1.6;min-height:38px;margin-top:10px}.subject-card-bottom{display:flex;justify-content:space-between;align-items:center;margin-top:auto;padding-top:14px;border-top:1px solid #eaf0f6;color:#54718b;font-size:11px}.subject-card-bottom b{font-weight:750}.arrow-circ{width:31px;height:31px;border-radius:50%;background:var(--subject-bg);color:var(--subject-color);display:grid;place-items:center;font-size:17px}
.featured-heading{margin:3px 0 20px}.featured-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;margin-bottom:36px}.featured-card{overflow:hidden;background:#fff;border:1px solid #e3ebf3;border-radius:17px;box-shadow:0 6px 21px #1d456711}.featured-art{height:133px;position:relative;overflow:hidden;display:flex;align-items:center;justify-content:center;background:var(--subject-bg)}.featured-art svg{width:190px;height:129px}.featured-subject{position:absolute;left:13px;top:11px;background:#ffffffdb;color:var(--subject-color);font-size:10px;font-weight:800;padding:5px 9px;border-radius:40px}.featured-copy{padding:15px 16px}.featured-overline{color:var(--subject-color);font-size:9px;letter-spacing:.1em;font-weight:900}.featured-copy h3{font-size:16px;margin:7px 0 5px;line-height:1.4;color:#234764}.featured-copy p{font-size:11px;color:#788da1;line-height:1.6;min-height:55px}.featured-link{display:flex;align-items:center;justify-content:space-between;width:100%;font-size:11px;font-weight:850;color:var(--subject-color);border:0;border-top:1px solid #eaf0f5;background:white;text-align:left;padding:13px 0 0;margin-top:7px}.featured-link:hover{text-decoration:underline}.featured-link span{font-size:17px}
.workflow-panel{display:grid;grid-template-columns:minmax(210px,.8fr) minmax(0,1.3fr);gap:26px;align-items:center;background:#fff;border:1px solid #e3eaf5;border-radius:20px;padding:25px;margin-bottom:18px}.workflow-panel h2{font-size:24px;letter-spacing:-.035em;line-height:1.2;margin:7px 0 10px}.workflow-panel p{color:#7f91a5;font-size:12px;line-height:1.65}.workflow-steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.workflow-steps>div{background:#f5f8fc;border:1px solid #eaf0f7;padding:15px 10px;border-radius:13px}.workflow-steps span{color:#158b8c;font-size:20px;font-weight:850;display:block;margin-bottom:8px}.workflow-steps strong{font-size:11px;line-height:1.4;display:block;color:#31516d}.workflow-steps small{font-size:9.5px;color:#8798a8;display:block;margin-top:6px}.home-transparency{padding:13px 17px;background:#fffaf1;border:1px solid #f0e6ce;border-radius:12px;font-size:11.2px;color:#876c46;line-height:1.75}.home-transparency strong{color:#735221}
/* Lesson view: subject cover, accessible tabs and clear academic content */
.academic-lesson-hero.lesson-hero{padding:28px 30px;border:1px solid #dce6f0;border-radius:22px;display:grid;grid-template-columns:minmax(0,1.5fr) minmax(180px,.45fr);gap:20px;position:relative;overflow:hidden;background:linear-gradient(110deg,#fff 5%,var(--subject-bg) 100%);box-shadow:0 12px 28px #1a426908;margin-bottom:15px}.academic-lesson-hero:after{content:"";position:absolute;right:-75px;top:-100px;width:275px;height:275px;border:35px solid #ffffff81;border-radius:50%;pointer-events:none}.academic-lesson-hero .lesson-hero-text{position:relative;z-index:2}.academic-lesson-hero .trail{font-size:10px;color:#8799ab;margin-bottom:13px}.academic-lesson-label{display:inline-flex;align-items:center;background:#fff;padding:7px 12px;border:1px solid #e8edf4;color:var(--subject-color);font-size:10px;letter-spacing:.08em;font-weight:900;border-radius:40px}.academic-lesson-hero h1{font-size:clamp(28px,3vw,40px);font-weight:850;line-height:1.17;color:#203f5c;margin:12px 0 6px;letter-spacing:-.045em}.academic-lesson-hero .en-title{font-size:16px;color:var(--subject-color);font-weight:720}.academic-lesson-desc{font-size:12.2px;color:#657f91;line-height:1.65;max-width:650px;margin-top:13px}.lesson-hero-actions{display:flex;gap:9px;flex-wrap:wrap;margin-top:18px}.lesson-hero-actions .btn.primary{background:var(--subject-color);border-color:var(--subject-color);color:white;padding:11px 15px}.lesson-hero-actions .btn.secondary-outline{border-color:var(--subject-color);background:#fff;color:var(--subject-color);padding:11px 15px}.academic-lesson-hero .lesson-pills{margin-top:19px;display:flex;flex-wrap:wrap;gap:7px}.academic-lesson-hero .lesson-pills .pill{font-size:9.5px;background:#fff9;border:1px solid #dfe8ef;border-radius:30px;padding:5px 9px;color:#698098}.academic-lesson-picture{display:grid;place-items:center;align-self:stretch;position:relative;z-index:1;min-height:190px}.academic-lesson-picture svg{width:100%;height:205px;max-width:320px;filter:drop-shadow(0 10px 13px #16486716)}.lesson-figure-stamp{position:absolute;bottom:6px;right:9px;color:var(--subject-color);border:1px solid #ffffffa0;background:#ffffff99;border-radius:40px;padding:5px 13px;font-size:10px;font-weight:850;letter-spacing:.07em}.lesson-quickfacts{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-bottom:18px}.lesson-quickfacts>div{background:#fff;border:1px solid #e5ebf3;border-radius:13px;padding:13px 17px;display:grid;grid-template-columns:37px 1fr;column-gap:9px;align-items:center;box-shadow:0 3px 12px #1b446508}.quick-icon{grid-row:1/3;background:var(--subject-bg,#e8f4fa);color:var(--subject-color,#118788);border-radius:11px;width:35px;height:35px;display:grid;place-items:center;font-size:22px}.lesson-quickfacts strong{font-size:12px;color:#31516f}.lesson-quickfacts small{font-size:10px;color:#8998a8}.toolbar-row{margin-top:4px}.tabbar{background:#fff;border:1px solid #e0e8f2;border-radius:13px;padding:5px;gap:4px;box-shadow:0 3px 12px #143e6005}.tabbar .tab{border-radius:9px;padding:10px 11px;font-size:11px;white-space:nowrap;color:#637b91}.tabbar .tab.active{color:var(--subject-color);background:var(--subject-bg);font-weight:900}.secondary-tools{white-space:nowrap}.body-grid{gap:17px}.panel{border-radius:17px;border:1px solid #e3eaf3;box-shadow:0 6px 23px #153c5c08}.panel-head{margin-bottom:22px}.panel-head h2{font-size:23px;color:#254761;letter-spacing:-.04em}.mini-label{letter-spacing:.1em;color:#2e8794}.visual-stage{background:#f9fcff;border-radius:15px}.sgk-card{border-radius:13px;box-shadow:0 3px 10px #143c6007}.sgk-card-head{background:#f5f9fc}.sgk-card details summary{color:#167e87}.lesson-hero .lesson-medallion{display:none}
/* Better responsive navigation and reading width */
@media(max-width:1450px){.header-links button{padding:8px;font-size:11px}.source-chip{display:none}.subject-cards.academic-subjects,.featured-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.academic-subject-card{min-height:288px}.academic-hero .hero-illustration{min-height:275px}.workflow-panel{grid-template-columns:1fr}.workflow-panel h2{max-width:600px}}
@media(max-width:1050px){.header-links{display:none}.home-search-section{grid-template-columns:1fr}.home-search-results{grid-column:1}.hero-campus.academic-hero{grid-template-columns:1fr;padding:32px}.academic-hero .hero-illustration{display:none}.academic-hero h1{font-size:43px}.subject-cards.academic-subjects{grid-template-columns:repeat(2,minmax(0,1fr))}.lesson-quickfacts{gap:7px}.lesson-quickfacts>div{padding:11px}}
@media(max-width:850px){.sidebar{height:100dvh}.header-bar{height:65px}.breadcrumbs{font-size:10px}.source-chip{display:none}.academic-lesson-hero.lesson-hero{grid-template-columns:minmax(0,1fr) 160px}.academic-lesson-picture svg{height:165px}.academic-lesson-hero h1{font-size:30px}.featured-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:620px){.header-bar{height:61px}main{padding:15px 14px 34px}.hero-campus.academic-hero{border-radius:18px;padding:29px 21px;min-height:0;margin-bottom:13px}.academic-hero h1{font-size:35px}.academic-hero p{font-size:12px}.hero-credentials{gap:7px 12px;margin-top:19px}.hero-credentials strong{font-size:14px}.hero-credentials span+span{padding-left:10px}.academic-hero .hero-actions{margin-top:18px}.academic-hero .hero-actions .btn{font-size:10px;padding:10px}.home-search-section{padding:14px;margin-bottom:27px}.home-section-heading h2{font-size:22px}.home-section-heading .academic-counter{display:none}.subject-cards.academic-subjects{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-bottom:27px}.academic-subject-card{min-height:270px;border-radius:15px}.academic-subject-card .subject-card-top{padding:12px 11px 0}.subject-art-scene{height:120px}.subject-art-scene svg{height:115px}.subject-card-details{padding:13px 12px}.subject-card-details>strong{font-size:18px}.subject-en{font-size:9px}.subject-description{font-size:10px;margin-top:7px;min-height:47px}.subject-card-bottom{font-size:10px}.arrow-circ{height:26px;width:26px}.featured-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-bottom:25px}.featured-art{height:105px}.featured-copy{padding:10px 12px}.featured-copy h3{font-size:13px}.featured-copy p{font-size:10px;min-height:65px}.featured-subject{font-size:9px}.workflow-panel{padding:17px;gap:15px}.workflow-steps{grid-template-columns:repeat(2,minmax(0,1fr))}.academic-lesson-hero.lesson-hero{grid-template-columns:1fr;padding:20px;border-radius:16px}.academic-lesson-hero h1{font-size:29px}.academic-lesson-desc{font-size:11px}.academic-lesson-picture{display:none}.academic-lesson-hero .lesson-pills .pill{font-size:9px}.lesson-quickfacts{grid-template-columns:1fr;gap:6px;margin-bottom:14px}.lesson-quickfacts>div{padding:9px 13px}.tabbar{border-radius:12px}.tabbar .tab{font-size:11px}.panel-head h2{font-size:21px}.site-footer{padding:16px}}
@media(max-width:360px){.subject-cards.academic-subjects,.featured-grid{grid-template-columns:1fr}.academic-subject-card{min-height:240px}.subject-art-scene{height:138px}.subject-description{min-height:0}}
@media(prefers-reduced-motion:reduce){.academic-subject-card,.btn,.sidebar{transition:none!important}html{scroll-behavior:auto}}
@media print{.home-search-section,.hero-campus,.academic-subjects,.featured-grid,.workflow-panel,.home-transparency,.hero-credentials,.lesson-hero-actions,.lesson-quickfacts,.header-links{display:none!important}.academic-lesson-hero.lesson-hero{display:block;background:white!important;border-bottom:1px solid #cbd5df!important}.academic-lesson-hero .lesson-hero-text{display:block}.academic-lesson-picture{display:none}}