/* Studio polish: strong hierarchy, richer surfaces and purpose-built collection pages. */
:root{--violet:#6659ad;--violet-bg:#eeeafa;--spotlight:#e3f1e6;--glass:#f8f8f0ed}
:root[data-theme="dark"]{--violet:#beb2ff;--violet-bg:#211f37;--spotlight:#153d39;--glass:#0b1219ed}
::selection{background:var(--teal);color:var(--paper)}header{background:var(--glass);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px)}header .nav-cta{border-radius:24px;padding:8px 17px}header .ask-ai{border-radius:24px;background:var(--accent-fill);color:var(--accent-ink);border-color:var(--accent-fill)}.desktop-rail{background:linear-gradient(180deg,var(--paper),var(--white))}.desktop-rail>a[aria-current]{background:linear-gradient(90deg,var(--surface-soft),transparent);border-radius:7px}.brand-icon{box-shadow:0 3px 15px #57c7a51b}.home .workspace-greeting h2{font-family:'Segoe UI',Arial,sans-serif;font-weight:600;letter-spacing:-.8px}.home .hero{position:relative;background:radial-gradient(ellipse at 90% 10%,var(--spotlight),transparent 60%),linear-gradient(125deg,var(--white),var(--surface-soft));box-shadow:0 20px 70px #00000012;border-radius:24px}.home .hero:before{content:'';position:absolute;inset:0 0 auto;height:1px;background:linear-gradient(90deg,transparent,var(--teal),transparent);opacity:.65}.home .hero-copy{min-width:0}.home .hero h1{font-family:'Segoe UI',Arial,sans-serif;font-weight:650;font-size:clamp(40px,4.3vw,66px);letter-spacing:-2.8px;line-height:1.06}.home .hero h1 em{font-family:var(--serif);font-size:1.12em;font-weight:400}.home .hero-copy>p{font-size:14px;line-height:1.85}.home .hero .button{border-radius:9px;box-shadow:0 5px 20px #58cfad16}.hero .math-art svg{filter:drop-shadow(0 0 15px #73dcc218)}.feature{border-radius:17px;background:linear-gradient(140deg,var(--white),var(--paper))}.feature:nth-child(3){background:linear-gradient(140deg,var(--violet-bg),var(--white))}.feature:nth-child(3) .tile-icon,.feature:nth-child(3) .card-arrow{color:var(--violet)}.feature .card-arrow{display:grid;place-items:center;width:30px;height:30px;background:var(--paper);border:1px solid var(--line);border-radius:50%;font-size:17px}.feature:hover .card-arrow{background:var(--accent-fill);color:var(--accent-ink)}.section-heading .eyebrow{font-size:9px;letter-spacing:1.7px}.study-strip{box-shadow:0 8px 30px #0000000b}.practice-choice{box-shadow:0 12px 35px #00000010}.practice-choice.advanced{background:linear-gradient(140deg,var(--violet-bg),var(--white))}.practice-choice.advanced .choice-tag,.practice-choice.advanced .choice-icon{color:var(--violet)}.exam-card{background:linear-gradient(160deg,var(--white),var(--paper));box-shadow:0 16px 45px #00000013}.question-map{border-radius:18px}.answer-option{transition:border-color .18s,background .18s,box-shadow .18s}.answer-option.selected{box-shadow:inset 3px 0 var(--teal)}.article main h2{padding-bottom:13px;border-bottom:1px solid var(--line)}.article main>p{border-radius:13px}.ai-banner{background:radial-gradient(ellipse at 0 20%,var(--spotlight),transparent 70%),var(--white);border-radius:20px}.portal-heading{padding:12px 0 36px}.portal-kicker{display:block;font-size:9px;font-weight:650;letter-spacing:1.7px;color:var(--teal)}.portal-heading h1{font-family:'Segoe UI',Arial,sans-serif;font-size:clamp(40px,4.3vw,62px);font-weight:600;line-height:1.12;letter-spacing:-2px;margin:19px 0 20px;overflow-wrap:anywhere}.portal-heading h1 em{font-family:var(--serif);font-size:1.08em;font-weight:400}.portal-heading>p{font-size:14px;line-height:1.9;color:var(--muted);max-width:610px}.portal-chips{display:flex;gap:8px;flex-wrap:wrap;margin-top:23px}.portal-chips>span{font-size:10px;color:var(--muted);border:1px solid var(--line);padding:6px 12px;border-radius:20px;background:var(--white)}.vault-collection{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:22px}.vault-card{position:relative;isolation:isolate;overflow:hidden;display:block;padding:30px;border:1px solid var(--line);border-radius:20px;background:radial-gradient(ellipse at 95% 50%,var(--spotlight),transparent 70%),var(--white);min-width:0}.vault-card.violet{background:radial-gradient(ellipse at 95% 50%,var(--violet-bg),transparent 85%),var(--white)}.vault-card-top{display:flex;justify-content:space-between;align-items:center;gap:15px;position:relative;z-index:1}.vault-arrow{display:grid;place-items:center;width:34px;height:34px;border-radius:50%;border:1px solid var(--line);font-size:19px;color:var(--teal);flex-shrink:0}.class-numeral{font-size:83px;letter-spacing:-5px;line-height:1;font-weight:600;color:var(--teal);display:flex;align-items:end;gap:16px;margin:25px 0}.class-numeral>span{font-size:9px;letter-spacing:2px;color:var(--muted);line-height:2.8}.violet .portal-kicker,.violet .class-numeral,.violet .vault-arrow{color:var(--violet)}.vault-card h2{font-size:28px;letter-spacing:-.7px;margin-bottom:15px;position:relative;z-index:1}.vault-card>p{font-size:13px;color:var(--muted);max-width:310px;min-height:48px;position:relative;z-index:1}.vault-bottom{display:flex;justify-content:space-between;gap:15px;padding-top:22px;margin-top:25px;border-top:1px solid var(--line);font-size:10px;position:relative;z-index:1}.vault-bottom>span{color:var(--muted)}.vault-bottom b{font-weight:600;color:var(--teal)}.formula-watermark{position:absolute;right:15px;top:110px;font:60px var(--serif);opacity:.055;transform:rotate(-12deg);z-index:-1;pointer-events:none}.vault-card:hover,.explore-card:hover{transform:translateY(-4px);border-color:var(--teal);box-shadow:0 18px 45px #00000020}.vault-card:hover .vault-arrow,.explore-card:hover .vault-arrow{background:var(--accent-fill);color:var(--accent-ink)}.reference-strip{display:flex;align-items:center;gap:20px;padding:25px 28px;background:var(--white);border:1px solid var(--line);border-radius:14px;margin:20px 0}.reference-icon{display:grid;place-items:center;width:52px;height:52px;border:1px solid var(--line);border-radius:12px;font:32px var(--serif);color:var(--teal);background:var(--surface-soft);flex-shrink:0}.reference-strip h2{font:22px/1.4 var(--serif);letter-spacing:0;margin:7px 0 3px}.reference-strip p{font-size:12px;color:var(--muted);margin:0}.reference-strip>.vault-arrow{margin-left:auto}.reference-strip:hover{border-color:var(--teal)}.coming-soon{display:flex;align-items:center;gap:22px;padding:30px;border:1px dashed var(--line);border-radius:15px;margin-top:30px;background:linear-gradient(120deg,var(--surface-soft),var(--paper))}.soon-symbol{font-size:35px;color:var(--teal)}.coming-soon h2{font:23px/1.4 var(--serif);margin:8px 0 4px;letter-spacing:0}.coming-soon p{font-size:13px;color:var(--muted);margin:0}.coming-soon>a{margin-left:auto;white-space:nowrap;font-size:11px;color:var(--teal);border-bottom:1px solid var(--line);padding-bottom:5px}.explore-collection{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.explore-card{display:flex;flex-direction:column;padding:25px;border:1px solid var(--line);border-radius:17px;background:var(--white);min-width:0}.explore-card:nth-child(3n+2){background:linear-gradient(155deg,var(--surface-soft),var(--white))}.explore-card:nth-child(3n){background:linear-gradient(155deg,var(--violet-bg),var(--white))}.explore-card .portal-kicker{font-size:8px}.explore-card .vault-arrow{width:27px;height:27px;font-size:16px}.explore-symbol{font:42px var(--serif);color:var(--teal);margin:26px 0 22px;line-height:1}.explore-card h2{font:25px/1.25 var(--serif);margin-bottom:15px;letter-spacing:-.5px}.explore-card p{font-size:12px;line-height:1.9;color:var(--muted)}.explore-card>strong{font-size:11px;font-weight:600;color:var(--teal);padding-top:18px;margin-top:auto;border-top:1px solid var(--line)}.portal main{animation:studio-arrive .35s ease-out}@keyframes studio-arrive{from{opacity:.3;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}
@media(min-width:761px) and (max-width:1100px){.home .hero h1{font-size:41px;letter-spacing:-2px}.explore-collection{grid-template-columns:repeat(2,minmax(0,1fr))}.vault-card{padding:23px}.class-numeral{font-size:70px}.vault-bottom{flex-direction:column;gap:8px}.coming-soon{flex-wrap:wrap}.coming-soon>a{margin-left:55px}.portal-heading h1{font-size:46px}.vault-card h2{font-size:25px}}
@media(max-width:760px){.home .hero{padding:27px 23px;border-radius:19px}.home .hero h1{font-size:44px;letter-spacing:-1.8px;max-width:100%}.home .hero h1 em{font-size:1.15em}.home .hero-copy>p{font-size:12px;max-width:95%}.home .hero .math-art{top:70px;right:-100px;opacity:.14}.home .feature .card-arrow{width:25px;height:25px;font-size:14px;right:12px}.home .feature p{max-width:89%}.workspace-greeting h2{font-size:23px!important}.portal-heading{padding:6px 0 28px}.portal-kicker{font-size:8px;letter-spacing:1.3px}.portal-heading h1{font-size:39px;letter-spacing:-1.6px;line-height:1.14;margin:16px 0}.portal-heading>p{font-size:12px;line-height:1.85}.portal-chips{gap:6px;margin-top:18px}.portal-chips>span{font-size:9px;padding:5px 10px}.vault-collection{grid-template-columns:1fr;gap:15px}.vault-card{padding:24px;border-radius:16px}.class-numeral{font-size:68px;margin:18px 0;letter-spacing:-3px}.vault-card h2{font-size:27px}.vault-card>p{min-height:0;font-size:12px;max-width:100%}.vault-bottom{font-size:9px;margin-top:20px;padding-top:18px;gap:8px}.vault-card-top .portal-kicker{font-size:8px}.vault-arrow{width:29px;height:29px;font-size:17px}.reference-strip{padding:20px 17px;gap:14px;align-items:start}.reference-icon{width:38px;height:43px;font-size:27px}.reference-strip h2{font-size:20px}.reference-strip p{font-size:11px;line-height:1.7}.reference-strip>.vault-arrow{width:24px;height:24px;font-size:14px}.reference-strip .portal-kicker{font-size:7px}.coming-soon{padding:23px 20px;flex-wrap:wrap;gap:15px;margin-top:25px}.soon-symbol{font-size:26px}.coming-soon>div{flex:1;min-width:200px}.coming-soon h2{font-size:23px}.coming-soon>a{margin-left:0;margin-top:5px}.explore-collection{grid-template-columns:1fr;gap:14px}.explore-card{position:relative;padding:22px}.explore-card .vault-card-top{margin-bottom:15px}.explore-symbol{position:absolute;top:65px;left:22px;font-size:30px;margin:0;width:46px;height:46px;display:grid;place-items:center;background:var(--paper);border:1px solid var(--line);border-radius:10px}.explore-card h2,.explore-card p{margin-left:63px}.explore-card h2{font-size:24px;margin-bottom:9px}.explore-card p{font-size:12px}.explore-card>strong{padding-top:15px;margin-top:8px;font-size:11px}.feature:hover,.vault-card:hover,.explore-card:hover{transform:none}}
@media(max-width:360px){.home .hero h1{font-size:37px}.portal-heading h1{font-size:34px}.vault-bottom{flex-direction:column}.coming-soon>div{min-width:0}.reference-strip h2{font-size:18px}.reference-strip{gap:10px}.portal-heading{overflow-wrap:anywhere}}
@media(prefers-reduced-motion:reduce){.portal main{animation:none}*{transition:none!important}}
@keyframes studio-arrive{from{transform:translateY(8px)}to{transform:translateY(0)}}