/* Current visual direction. UI/UX Pro Max: Swiss grid + Geometric Modern. */
:root{--sans:'Work Sans',Arial,sans-serif;--head:'Outfit',Arial,sans-serif;--editorial:var(--head);--bg:#f3f6fb;--panel:#fff;--text:#172741;--muted:#53647a;--border:#dce4ef;--blue:#2359d1;--soft:#edf3ff;--yellow:#f4c451;--side:#101e35;--focus:#2359d1;--success:#19714d;--danger:#b52f42;--radius:16px;--shadow:0 5px 20px #10274506}
body.dark{--bg:#101b2f;--panel:#17263e;--text:#eef4ff;--muted:#b5c4d9;--border:#364963;--blue:#a8c8ff;--soft:#233b60;--side:#0c172a;--focus:#b4d1ff;--success:#91e6b7;--danger:#ffb3c0}
body{font-family:var(--sans);letter-spacing:-.15px}h1,h2,h3{font-family:var(--head);font-weight:600;letter-spacing:-.6px}h1{font-size:clamp(32px,3.6vw,46px);line-height:1.13}.eyebrow{font-size:11px;font-weight:600;letter-spacing:1.65px}.panel{border-radius:16px;box-shadow:var(--shadow)}.button{background:#2359d1;color:#fff;border:1px solid #2359d1;border-radius:10px;min-height:48px;box-shadow:0 4px 10px #2359d119;font-size:14px;font-weight:600}.button:hover{background:#1847b4;border-color:#1847b4;color:#fff}.button.secondary{background:var(--panel);border:1px solid var(--border);color:var(--text);box-shadow:none}.button.secondary:hover{background:var(--soft);border-color:var(--blue);color:var(--blue)}.dark .button:not(.secondary):not(.yellow){background:#a8c8ff;border-color:#a8c8ff;color:#102a50}.icon-button{border-radius:12px;background:var(--panel)}
body:not(.entry-mode)>aside{background:var(--side);border-right:0;color:#adbed5;padding:30px 18px}.brand{color:#fff;letter-spacing:-.5px;font-family:var(--head);font-size:23px}.brand small{color:#a9bdd7;font-size:8px;letter-spacing:1.6px;font-family:var(--sans)}.brand-icon{background:var(--yellow);color:#172741;box-shadow:0 4px 12px #0002;border-radius:11px}.nav-label{color:#8fa6c5;font-size:10px;letter-spacing:1.6px;margin-top:46px}nav{gap:8px}nav a{color:#b9c9df;min-height:50px;font-size:14px;border-radius:10px}nav a span{font-size:13px}nav a .ui-icon{width:21px;height:21px;stroke-width:1.8}nav a:hover{background:#1e3353;color:#fff}nav a.active{background:#2359d1;color:#fff;box-shadow:0 4px 18px #0002}nav a.active .ui-icon{color:#fff}nav a b{border-color:#ffffff40;color:inherit}.sidebar-note{border-top:1px solid #ffffff16;padding:24px 12px 20px}.sidebar-note>span{color:#f4c451;font-size:9px}.sidebar-note p{color:#b2c2d8;line-height:1.8}.line-circuit{color:#5c7b9e}.source-link{border-color:#ffffff1a;color:#b9c9df;font-size:12px}.source-link:hover,.source-link[aria-current=page]{color:#fff;background:#1e3353}.shell>header{background:var(--panel);height:76px;border-bottom:1px solid var(--border)}.breadcrumb{font-size:12px}.private-badge{font-size:11px}.profile-button{font-weight:600;font-size:12px}.sync-label{font-size:11px}.header-actions{gap:14px}main{padding-top:36px}.intro h1,.article-head h1{font-family:var(--head);font-weight:600;letter-spacing:-1px}.intro p{font-size:15px}.search{border:1px solid var(--border);border-radius:12px;box-shadow:0 3px 12px #10274503;padding:0 18px;margin-bottom:26px}.search input{font-size:16px;min-height:58px}.search .ui-icon{color:var(--blue)}.search kbd{border-radius:6px;border-color:var(--border);font-size:11px}
.ux-welcome{margin-bottom:25px;align-items:center}.ux-welcome h1{font-family:var(--head);font-size:clamp(34px,3.5vw,46px);line-height:1.12;letter-spacing:-1.3px;margin:14px 0}.ux-welcome h1 span{color:var(--blue)}.ux-welcome p{font-size:14px;max-width:460px}.ux-top-link{background:var(--panel);border:1px solid var(--border);border-radius:10px;padding:10px 16px;font-size:12px}.ux-top-link:hover{border-color:var(--blue)}.ux-continue{border:0;border-radius:18px;background:#102747;color:#fff;grid-template-columns:minmax(0,1.7fr) minmax(230px,1fr);box-shadow:0 10px 26px #10274713;margin-bottom:26px}.ux-continue-copy{padding:32px 34px}.ux-continue-copy .eyebrow{background:#f4c451;color:#253148;border-radius:5px;padding:5px 9px;font-size:9px;letter-spacing:1px}.ux-continue h2{font-family:var(--head);font-weight:600;font-size:31px;line-height:1.17;letter-spacing:-.6px;color:#fff;margin:14px 0}.ux-continue-meta{color:#b4c9e7;font-size:11px}.ux-continue p{color:#c8d8ec;font-size:14px;line-height:1.8;max-width:460px;margin-bottom:22px}.ux-continue-actions{gap:18px}.ux-continue .button,.dark .ux-continue .button{background:#f4c451;color:#182b46;border-color:#f4c451;box-shadow:none;font-size:13px}.ux-continue .button:hover{background:#ffdb78;border-color:#ffdb78}.ux-continue-actions>a:last-child{color:#e1eaf8;font-size:12px;text-decoration:underline;text-underline-offset:4px}.ux-continue-progress{position:relative;isolation:isolate;overflow:hidden;background:#153458;border-left:1px solid #ffffff10;padding:28px;gap:16px}.studio-circuit{position:absolute;inset:0;width:100%;height:100%;z-index:-1;stroke:#5b8ac4;stroke-width:1;opacity:.23;object-fit:cover}.studio-circuit circle{fill:#17365c;stroke:#9ec5f5}.studio-progress-label{font-size:9px;letter-spacing:2px;font-weight:600;color:#c5d8ef}.ux-ring{width:126px;height:126px;background:conic-gradient(#f4c451 calc(var(--value)*1%),#ffffff20 0);box-shadow:0 0 0 12px #ffffff03}.ux-ring:before{inset:7px;background:#153458}.ux-ring strong{font-family:var(--head);font-weight:600;font-size:36px;color:#fff;letter-spacing:-1px}.ux-continue-progress p{font-size:12px;margin:0;color:#e2edff}.ux-continue-progress small{font-size:11px;color:#b8cce7}.stats{border:0;gap:14px;margin:0 0 32px}.stat{background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:20px!important;position:relative;box-shadow:var(--shadow)}.stat:last-child{border-right:1px solid var(--border)}.stat:before{content:'';display:block;width:22px;height:3px;border-radius:2px;background:var(--blue);margin-bottom:14px}.stat:nth-child(2):before{background:#26936b}.stat:nth-child(3):before{background:#bd8216}.stat:nth-child(4):before{background:#7a5ec7}.stat strong{font-family:var(--head);font-size:30px;font-weight:600;line-height:1.1;margin:10px 0 9px;letter-spacing:-.8px}.stat>span:not(.stat-icon){font-size:11px;font-weight:500}.stat small{font-size:11px}.section-head{margin:30px 0 18px}.section-head h2{font-size:23px;font-weight:600}.section-head a{font-size:12px;color:var(--blue);display:flex;align-items:center;gap:8px;min-height:44px}
.ux-lesson-card{box-shadow:0 4px 18px #10274705;transition:border-color 180ms,box-shadow 180ms}.ux-lesson-card:hover{border-color:#97b2df;box-shadow:0 8px 24px #1027470d}.ux-lesson-art{height:176px;background:#edf2f8;border-bottom:1px solid var(--border)}.ux-lesson-art img{object-position:center 48%;mix-blend-mode:multiply}.ux-lesson-art>span{background:#142d4d;color:white;font-size:10px;letter-spacing:1.2px;padding:6px 10px;border-radius:6px;top:16px;left:18px;box-shadow:0 3px 9px #10274719}.ux-lesson-body{padding:24px}.ux-lesson-body h2{font-family:var(--head);font-size:23px;font-weight:600;line-height:1.25;letter-spacing:-.5px}.ux-lesson-body>p{font-size:14px;line-height:1.8}.ux-lesson-meta{font-size:12px;margin-bottom:13px}.badge{border:0;background:var(--soft);color:var(--blue);font-size:11px;padding:5px 9px;border-radius:6px;font-weight:500}.ux-lesson-body progress{height:5px;margin:16px 0 10px}.ux-lesson-foot{padding-top:16px;margin-top:8px}.ux-lesson-foot a{font-size:12px}.ux-review-card{box-shadow:none;background:var(--panel);padding:24px}.ux-review-card>span{background:var(--soft);color:var(--blue)}.ux-review-card h2{font-size:19px}.ux-review-card p{font-size:13px;line-height:1.8}.ux-practice-card{border-top:3px solid var(--blue)}.ux-practice-card h2{font-family:var(--head);font-weight:600}.filter-row{border-radius:12px;box-shadow:none}.filter-row label{font-size:12px;font-weight:500}
.article-head{padding-bottom:26px}.article-head h1{font-size:clamp(32px,3.5vw,44px);line-height:1.14}.article-head>p{font-size:16px;line-height:1.8}.article-head>.eyebrow{display:inline-block;background:var(--soft);color:var(--blue);border-radius:6px;padding:6px 10px;font-size:10px}.reader-layout{gap:28px}.toc{border-right:0;padding:0 16px 12px 0}.toc a{font-size:12px;color:var(--muted);border-left:2px solid transparent;border-radius:0 6px 6px 0}.toc a.ux-current{border-left-color:var(--blue)}.article>section{border-radius:14px;padding:32px;box-shadow:0 3px 14px #10274703;border-color:var(--border)}.article>section>.eyebrow{color:var(--blue);font-size:10px;letter-spacing:1.4px}.article>section h2{font-family:var(--head);font-size:28px;font-weight:600;letter-spacing:-.6px;line-height:1.25;margin:12px 0 20px}.article p{font-family:var(--sans);font-size:17px;line-height:1.9;letter-spacing:-.2px}.article>.chapter-opening{background:var(--panel);border:1px solid var(--border);border-top:3px solid var(--blue)}.article .chapter-opening h2{font-family:var(--head);font-size:26px;font-weight:600}.article .worked-example{background:var(--soft);border-color:var(--blue)}.article .key-concept{background:color-mix(in srgb,var(--success) 7%,var(--panel));border-color:var(--success)}.article label.small{font-size:13px}.visual{background:var(--bg);border-radius:12px}.quiz-wrap h2,.flash h2{font-family:var(--head);font-weight:600!important}.quiz-wrap h2{font-size:27px!important;line-height:1.35}.flash{border-top:3px solid var(--blue);box-shadow:0 8px 28px #10274708}.flash h2{font-size:31px!important}.option{border-radius:10px;font-size:15px}.option.selected{background:var(--soft);border-color:var(--blue)}.option span{background:var(--bg);border-radius:7px}.feedback{border-radius:10px}.ux-reading-meter{background:#f4c451}.ux-reader-tools button{font-size:12px}.source-lesson h2{font-family:var(--head)!important;font-size:26px!important;font-weight:600!important}.material-note>strong{font-family:var(--head);font-size:22px}footer{background:var(--bg);font-size:10px}
.login-stage{background-color:#101e35;background-image:radial-gradient(ellipse at 15% 10%,#24529b55,transparent 65%),linear-gradient(#ffffff04 1px,transparent 1px),linear-gradient(90deg,#ffffff04 1px,transparent 1px);background-size:auto,48px 48px,48px 48px}.login-stage:before{border-color:#2359d126;opacity:.65}.login-stage:after{border-color:#6f9cda35}.login-card{border:0;border-top:4px solid #f4c451;box-shadow:0 30px 90px #0004;border-radius:20px;padding:40px;color:#172741}.login-card h1{font-family:var(--head);font-size:34px;font-weight:600;letter-spacing:-.8px}.login-brand{font-family:var(--head);font-size:25px;font-weight:600;color:#172741}.login-brand small{font-family:var(--sans);color:#53647a;letter-spacing:1.6px}.login-card .eyebrow{color:#2359d1}.login-card input{border-color:#a7b6ca}.login-card .login-note{font-size:12px}.login-card .forgot-link{color:#2359d1}.login-card .button{background:#2359d1;border-color:#2359d1;color:#fff}.password-hint{font-size:12px}
@media(max-width:1180px){.ux-continue{grid-template-columns:minmax(0,1.6fr) minmax(200px,1fr)}.ux-continue-copy{padding:28px}.ux-continue h2{font-size:29px}.stat{padding:18px!important}}
@media(max-width:1000px){.toc{background:var(--panel);border:1px solid var(--border);padding:12px 16px;border-radius:12px}}
@media(max-width:900px){body:not(.entry-mode)>aside{background:var(--side);border:0;padding-top:max(16px,env(safe-area-inset-top));padding-bottom:16px}.brand{font-size:22px}.brand-icon{width:38px;height:40px}.brand small{color:#b6c8df;font-size:7px}.source-link{background:#ffffff0a;border-color:#ffffff24;color:#d6e1f1;font-size:11px;border-radius:8px;padding:8px 10px}.source-link:hover,.source-link[aria-current=page]{color:#fff}.shell>header{height:auto;min-height:72px;padding:10px 18px;background:var(--panel)}nav{background:var(--panel);border-top:1px solid var(--border);box-shadow:0 -4px 18px #10274708}nav a{color:var(--muted);box-shadow:none;font-size:11px;min-height:58px}nav a span{font-size:10px}nav a.active{background:var(--soft);color:var(--blue);box-shadow:none}nav a.active .ui-icon{color:var(--blue)}nav a:hover{background:var(--soft);color:var(--blue)}.shell>main{padding-top:26px}.ux-welcome h1{font-size:36px;letter-spacing:-1px}.ux-welcome p{font-size:14px}.ux-continue{grid-template-columns:1fr;border-radius:15px}.ux-continue-copy{padding:26px}.ux-continue h2{font-size:29px}.ux-continue p{font-size:14px}.ux-continue-progress{border-left:0;border-top:1px solid #ffffff16;flex-direction:row;padding:20px 26px;gap:20px;justify-content:flex-start;text-align:left}.studio-progress-label{display:none}.ux-ring{width:74px;height:74px;box-shadow:none}.ux-ring:before{inset:5px}.ux-ring strong{font-size:25px}.ux-continue-progress p{font-size:12px;margin:0}.stats{gap:10px;margin-bottom:28px}.stat,.stat:nth-child(-n+2),.stat:nth-child(2){border:1px solid var(--border)}.stat{padding:17px!important}.stat strong{font-size:28px}.stat>span:not(.stat-icon),.stat small{font-size:11px}.stat:before{margin-bottom:12px}.ux-lesson-art{height:175px}.ux-lesson-body{padding:22px}.ux-lesson-body h2{font-size:24px}.section-head h2{font-size:23px}.section-head a{font-size:11px}.article-head h1{font-size:34px}.article>section{padding:26px 22px}.article>section h2{font-size:26px}.article p{font-size:16px}.article .chapter-opening h2{font-size:25px}.intro h1{font-size:34px}.flash h2{font-size:28px!important}.quiz-wrap h2{font-size:25px!important}.source-lesson h2{font-size:25px!important}.login-card{padding:34px 28px}.login-card h1{font-size:32px}.profile-button{font-size:11px}.header-actions{gap:6px}.sync-label{font-size:11px}.ux-top-link{display:none}.ux-reading-meter{top:0}}
@media(max-width:360px){.ux-welcome h1{font-size:32px}.ux-continue-copy{padding:23px}.ux-continue h2{font-size:26px}.ux-continue-actions{align-items:stretch;flex-direction:column;gap:8px}.ux-continue-actions .button{justify-content:center}.stat{padding:14px!important}.stat small{font-size:10px}.article-head h1{font-size:30px}.article>section{padding:22px 17px}.article>section h2{font-size:25px}.login-card{padding:28px 22px}.source-link{font-size:10px}.brand{font-size:20px}}
@media(max-width:900px) and (max-height:500px) and (orientation:landscape){body:not(.entry-mode)>aside{padding-top:8px;padding-bottom:8px}.shell>header{min-height:54px;padding-top:4px;padding-bottom:4px}nav a{min-height:48px}.login-card{padding:24px}}
@media(prefers-reduced-motion:reduce){.ux-lesson-card{transition:none}}

.entry-mode .login-stage{background-color:#101e35;background-image:radial-gradient(ellipse at 15% 10%,#24529b55,transparent 65%),linear-gradient(#ffffff05 1px,transparent 1px),linear-gradient(90deg,#ffffff05 1px,transparent 1px);background-size:auto,48px 48px,48px 48px}.entry-mode .login-stage:before{border-color:#2359d126}.entry-mode .login-stage:after{border-color:#6f9cda35}.dark .ux-continue .button:not(.secondary):not(.yellow){background:#f4c451;border-color:#f4c451;color:#182b46}