/* Student surfaces are scoped so existing subject applications keep their UI. */
[hidden]{display:none!important}.learning-language{display:flex;gap:7px;align-items:center;font:600 12px/1.4 system-ui,sans-serif;white-space:nowrap}.learning-language select{min-height:44px;max-width:105px;border:1px solid #b7c4d2;border-radius:7px;background:#fff;color:#173553;padding:4px 7px;font:inherit}
.student-surface{--ink:#102b47;--muted:#465b70;--blue:#1454a2;--orange:#b94a08;--paper:#fff;--line:#dce5ee;background:#fff;color:var(--ink);font:16px/1.65 system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}.student-surface .topbar{background:rgba(255,255,255,.97);border-color:var(--line);position:relative;padding-block:16px;flex-wrap:wrap}.student-surface .brand-type{color:var(--ink)}.student-surface .topbar nav a{color:#344d64}.student-surface .nav-search{color:var(--blue);border-color:var(--line);background:#f5f8fc}.student-surface a{color:var(--blue)}.student-surface h1,.student-surface h2,.student-surface h3{font-family:inherit;letter-spacing:-.035em;color:var(--ink);font-weight:650;line-height:1.22}.student-surface h1{font-size:clamp(2.6rem,5.5vw,5.3rem);margin:14px 0 22px}.student-surface h1 em{font-style:normal;color:var(--blue)}.student-surface h2{font-size:clamp(1.65rem,3.4vw,2.6rem)}.student-surface h3{font-size:1.35rem}.student-surface p{color:var(--muted)}.student-surface :focus-visible{outline:3px solid #b94a08;outline-offset:4px}.student-surface .v2-kicker{font-size:11px;letter-spacing:.12em;color:var(--orange);font-weight:750;text-transform:uppercase}.v2-hero,.v2-section,.v2-page-intro,.v2-counts{max-width:1240px;margin-inline:auto;padding:60px 36px}.v2-hero{display:grid;grid-template-columns:1.18fr 1fr;gap:65px;align-items:center;padding-top:70px}.v2-hero>div>p:not(.v2-kicker){max-width:620px}.v2-mission{font-size:1.18rem;font-weight:600}.v2-actions{display:flex;gap:12px;flex-wrap:wrap;margin:30px 0 12px}.v2-primary,.v2-secondary{display:inline-flex;align-items:center;justify-content:center;min-height:48px;border-radius:8px;padding:12px 20px;text-decoration:none!important;font:600 14px/1.5 system-ui,sans-serif;cursor:pointer;max-width:100%;text-align:center}.student-surface .v2-primary{background:#1454a2;color:#fff;border:1px solid #1454a2;box-shadow:0 5px 15px #1454a218}.student-surface .v2-secondary{color:#1454a2;border:1px solid #aebfd2;background:#fff}.v2-access{font-size:12px!important}.v2-science-note{background:linear-gradient(150deg,#f3f8fe,#eef5fc);padding:30px;border-radius:22px;border:1px solid #d6e4f4}.v2-science-note svg{width:100%;height:auto;color:#395a7a}.v2-science-note h2{font-size:1.3rem}.v2-science-note p{font-size:.9rem}.v2-counts{display:grid;grid-template-columns:repeat(4,1fr);padding-block:24px;border-top:1px solid #dce5ee;border-bottom:1px solid #dce5ee}.v2-counts>div{display:flex;flex-direction:column;gap:3px;padding:4px 22px;border-right:1px solid #dce5ee;font-size:12px;color:#465b70}.v2-counts>div:last-child{border:0}.v2-counts strong{font-size:2rem;letter-spacing:-.04em;color:#102b47}.v2-section{padding-top:64px;padding-bottom:42px}.v2-section-title{margin-bottom:28px;max-width:800px}.v2-section-title h2{margin:8px 0 12px}.v2-section-title>p{margin:0}.v2-path-grid,.v2-subject-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}.v2-path-card{border:1px solid #dce5ee;border-radius:12px;padding:22px;text-decoration:none!important;background:#fff;transition:background .15s,border-color .15s}.v2-path-card:hover{background:#f4f8fd;border-color:#719ac7}.v2-path-card>span>strong,.v2-path-card>span>span,.v2-path-card>span>b{display:block}.v2-path-card strong{font-size:1.15rem;color:#102b47}.v2-path-card span span{margin:12px 0 22px;color:#465b70;font-size:.9rem}.v2-path-card b{font-size:13px}.v2-muted{font-size:.84rem;max-width:950px;margin-top:22px}.v2-subject{padding:22px;border-radius:12px;background:#f4f7fb;text-decoration:none!important;display:block}.v2-subject h3{margin:0 0 14px}.v2-subject p{font-size:.88rem;line-height:1.7}.v2-subject span span{font-size:13px;font-weight:600}.v2-lab-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.v2-lab-card{position:relative;border:1px solid #dce5ee;border-radius:14px;padding:26px;background:#fff;overflow:hidden}.v2-lab-card h3{max-width:250px;margin:35px 0 14px}.v2-lab-card h3 a{text-decoration:none;color:#102b47}.v2-lab-card p:not(.v2-kicker){font-size:.91rem}.v2-lab-number{position:absolute;right:20px;top:38px;font-size:2.5rem;color:#dae6f3;font-weight:700;letter-spacing:-.06em}.v2-card-action{display:inline-block;margin-top:18px;font-size:13px;font-weight:650}.v2-discovery,.v2-purpose{display:grid;grid-template-columns:1fr 1fr;gap:65px;background:#f5f8fc;border-radius:18px;margin-top:32px;margin-bottom:20px}.v2-search label{display:block;font-size:13px;margin:20px 0 8px}.v2-search>div{display:flex;gap:8px}.v2-search input{background:white;border:1px solid #9aaec4;border-radius:6px;width:100%;min-width:0;min-height:48px;padding:10px;font:inherit}.v2-search button{background:#1454a2;color:#fff;border:0;border-radius:6px;padding:12px 18px;font-weight:650;cursor:pointer;min-height:48px}.student-surface .topic-shortcuts{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}.student-surface .topic-shortcuts a{font-size:12px;padding:6px 8px;background:#fff;border:1px solid #dce5ee;border-radius:5px;text-decoration:none}.v2-inline{display:block;margin-top:18px;font-size:14px}.v2-recent{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.v2-recent>a{padding:18px;border:1px solid #dce5ee;border-radius:8px;text-decoration:none;font-size:.92rem;overflow-wrap:anywhere}.v2-recent>a>span{display:block;font-size:12px;margin-top:10px}.v2-text-button{border:0;background:none;padding:12px 0;color:#1454a2;min-height:44px;font:inherit;text-decoration:underline;cursor:pointer}.v2-purpose h3{margin-top:0}.v2-page-intro{padding-bottom:25px}.v2-page-intro h1{font-size:clamp(2.3rem,4vw,3.6rem)}.v2-page-intro p{max-width:850px}.v2-path-links{display:flex;gap:10px;flex-wrap:wrap;margin:24px 0}.v2-path-links a{padding:9px 13px;border:1px solid #c3d2e1;border-radius:8px;font-size:14px;text-decoration:none}.v2-path-links a[aria-current]{background:#1454a2;color:#fff}.v2-navigator{display:flex;gap:15px;flex-wrap:wrap;align-items:end;margin:24px 0}.v2-navigator label{display:flex;flex-direction:column;gap:6px;font-size:13px;font-weight:600}.v2-navigator select{min-height:46px;padding:10px 36px 10px 12px;background:#fff;border:1px solid #93aac0;border-radius:6px;max-width:100%;font:inherit;color:#173553}.v2-chapter-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;align-items:start}.v2-chapter{border:1px solid #dce5ee;border-radius:8px;padding:18px}.v2-chapter summary{cursor:pointer;min-height:44px;font-weight:650;color:#173553}.v2-chapter small{display:block;margin-top:5px;font-weight:400;font-size:12px;color:#465b70}.v2-chapter ul{padding-left:18px;margin-bottom:0}.v2-chapter li{margin-bottom:16px;overflow-wrap:anywhere}.v2-glossary{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.v2-glossary article{padding:24px;background:#f5f8fc;border-radius:10px}.v2-glossary h2{font-size:1.5rem}.v2-glossary h2 span{display:block;margin-top:8px;font-size:1.2rem}.v2-formula{font:600 1.05rem/1.7 ui-monospace,monospace;color:#102b47!important}.student-surface .site-footer{margin-top:60px;background:#102b47;color:#fff}.student-surface .site-footer a,.student-surface .site-footer p{color:#e6edf6}.student-surface .footer-brand,.student-surface .footer-logo>span{color:#fff}.student-surface .site-footer strong{color:#fff}.student-surface .site-footer .footer-bottom{color:#c8d9ea}
@media(max-width:1000px){.v2-hero{gap:30px}.v2-path-grid,.v2-subject-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.v2-lab-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.v2-discovery,.v2-purpose{gap:30px}.student-surface .topbar{gap:16px}.student-surface .topbar nav{order:3;width:100%;justify-content:center;gap:20px}.student-surface .nav-search{margin-left:auto}}
@media(max-width:650px){.v2-hero,.v2-section,.v2-page-intro{padding:34px 20px}.v2-hero{grid-template-columns:1fr;gap:24px}.v2-hero h1{font-size:2.75rem}.v2-science-note{padding:22px}.v2-science-note svg{max-height:180px}.v2-counts{grid-template-columns:repeat(2,1fr);padding:12px 16px}.v2-counts>div{padding:12px 14px}.v2-counts>div:nth-child(2){border-right:0}.v2-counts strong{font-size:1.7rem}.v2-path-grid,.v2-subject-grid,.v2-lab-grid,.v2-chapter-grid,.v2-glossary,.v2-recent{grid-template-columns:1fr}.v2-discovery,.v2-purpose{grid-template-columns:1fr;border-radius:0;gap:35px}.v2-section-title h2{font-size:1.8rem}.v2-path-card{padding:20px}.v2-path-card span span{margin:8px 0 15px}.v2-lab-card h3{margin-top:26px}.v2-navigator{display:grid;grid-template-columns:1fr;gap:14px}.v2-navigator label,.v2-navigator select{width:100%}.student-surface .topbar{padding:12px 16px;gap:10px}.student-surface .brand-type{font-size:14px}.student-surface .brand-type small{font-size:7px}.student-surface .brand-emblem{width:38px;height:38px}.student-surface .nav-search{font-size:12px;padding:9px}.student-surface .nav-search kbd{display:none}.student-surface .topbar nav{justify-content:flex-start;overflow-x:auto;gap:18px;padding-block:6px}.student-surface .topbar nav a{white-space:nowrap;min-height:44px;display:flex;align-items:center}.learning-language{margin-left:auto}.learning-language>span{display:none}.student-surface .v2-actions{flex-direction:column;align-items:stretch}.student-surface .v2-primary,.student-surface .v2-secondary{font-size:14px}.v2-glossary article{padding:20px}}
@media(prefers-reduced-motion:reduce){.student-surface *{scroll-behavior:auto!important;transition:none!important;animation:none!important}}

.v2-chapter-results{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;align-items:start}.v2-navigator button[type=reset]{min-height:46px;border:1px solid #93aac0;border-radius:6px;background:white;color:#1454a2;padding:10px 18px;font:600 14px system-ui;cursor:pointer}@media(max-width:650px){.v2-chapter-results{grid-template-columns:1fr}}
.v2-breadcrumbs{max-width:1240px;margin:0 auto;padding:24px 36px 0;font-size:13px}.v2-breadcrumbs ol{display:flex;gap:12px;flex-wrap:wrap;list-style:none;margin:0;padding:0}.v2-breadcrumbs li+li::before{content:'›';margin-right:12px;color:#465b70}.v2-breadcrumbs a{display:inline-flex;align-items:center;min-height:44px}.v2-breadcrumbs li>span{display:inline-flex;align-items:center;min-height:44px}.v2-subject>div>span{font-size:13px;font-weight:600}@media(max-width:650px){.v2-breadcrumbs{padding:16px 20px 0}}