:root {
  --navy-950: #06172d;
  --navy-900: #092543;
  --navy-800: #0d355f;
  --blue-700: #075fae;
  --blue-600: #0b72ce;
  --blue-100: #e8f4ff;
  --paper: #f6f8fb;
  --white: #ffffff;
  --ink: #182536;
  --muted: #68778a;
  --line: #dfe6ee;
  --green: #1c8b63;
  --gold: #d8a22d;
  --sidebar-width: 250px;
  --shadow: 0 22px 60px rgba(8, 33, 61, 0.11);
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
body.igcse-learning { --blue-700: #9b2f3f; --blue-600: #b33a4d; --blue-100: #f8e9ec; }
.learning-boot { position: fixed; z-index: 100; inset: 0; display: grid; place-content: center; justify-items: center; gap: 16px; background: #f6f8fb; color: var(--muted); }
.learning-boot img { width: min(190px, 56vw); }
.learning-boot span { font-size: 10px; font-weight: 750; letter-spacing: .03em; }
body:not(.is-booting) .learning-boot { display: none; }
body.is-booting .app-shell { visibility: hidden; }
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button:focus-visible, a:focus-visible, input:focus-visible { outline: 3px solid rgba(36, 147, 238, 0.35); outline-offset: 2px; }

.app-shell { min-height: 100vh; display: grid; grid-template-columns: var(--sidebar-width) minmax(0, 1fr); }
.sidebar { position: sticky; z-index: 30; top: 0; height: 100vh; display: flex; flex-direction: column; padding: 25px 17px 18px; background: var(--white); border-right: 1px solid var(--line); }
.sidebar-head { display: flex; align-items: center; justify-content: space-between; min-height: 48px; padding: 0 9px; }
.brand { width: 165px; padding: 0; border: 0; background: transparent; cursor: pointer; }
.brand img { display: block; width: 100%; }
.icon-button { display: grid; place-items: center; border: 0; background: transparent; color: var(--navy-900); cursor: pointer; }
.icon-button svg { width: 22px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; }
.mobile-close, .menu-button { display: none; }

.main-nav { display: grid; gap: 6px; margin-top: 38px; }
.nav-item { width: 100%; display: grid; grid-template-columns: 22px 1fr; gap: 12px; align-items: center; min-height: 46px; padding: 0 13px; border: 0; border-radius: 10px; background: transparent; color: #607084; text-align: left; text-decoration: none; font-size: 12px; font-weight: 750; cursor: pointer; }
.nav-item svg { width: 20px; fill: none; stroke: currentColor; stroke-width: 1.65; stroke-linecap: round; stroke-linejoin: round; }
.nav-item:hover { background: #f2f6fa; color: var(--navy-900); }
.nav-item.is-active { background: var(--blue-100); color: var(--blue-700); }
.nav-item-home { min-height: 58px; margin-bottom: 7px; border: 1px solid #cfe0ef; background: #f4f9fe; color: var(--navy-900); }
.nav-item-home strong, .nav-item-home small { display: block; }
.nav-item-home strong { font-size: 12px; }
.nav-item-home small { margin-top: 3px; color: var(--muted); font-size: 8px; font-weight: 650; }

.eyebrow { margin: 0 0 7px; color: var(--blue-700); font-size: 9px; font-weight: 900; letter-spacing: 0.13em; text-transform: uppercase; }
.sidebar-summary { margin-top: auto; padding: 18px; border: 1px solid #dfe8f1; border-radius: 15px; background: linear-gradient(145deg, #f9fbfd, #eef5fb); }
.sidebar-summary > div { display: flex; align-items: baseline; justify-content: space-between; padding: 5px 0; }
.sidebar-summary strong { color: var(--navy-900); font-family: Georgia, serif; font-size: 24px; font-weight: 500; }
.sidebar-summary span, .sidebar-summary small { color: var(--muted); font-size: 9px; }
.sidebar-summary small { display: block; margin-top: 8px; }
.help-card { width: 100%; display: grid; grid-template-columns: 31px 1fr auto; gap: 10px; align-items: center; margin-top: 12px; padding: 12px; border: 0; border-radius: 13px; background: var(--navy-950); color: #fff; text-align: left; cursor: pointer; }
.help-card strong, .help-card small { display: block; }
.help-card strong { font-size: 10px; }.help-card small { margin-top: 2px; color: #a8bfd4; font-size: 8px; }
.help-icon { width: 30px; height: 30px; display: grid; place-items: center; border-radius: 50%; background: rgba(255,255,255,.12); font-weight: 900; }

.sidebar-scrim { display: none; }
.main-stage { min-width: 0; }
.topbar { position: sticky; z-index: 20; top: 0; height: 70px; display: flex; align-items: center; justify-content: space-between; padding: 0 clamp(28px, 4vw, 62px); border-bottom: 1px solid rgba(219,228,237,.9); background: rgba(255,255,255,.91); backdrop-filter: blur(14px); }
.topbar-context { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 10px; font-weight: 700; }
.topbar-home-link { display: inline-flex; align-items: center; min-height: 34px; padding: 0 11px; border: 1px solid #cbd9e5; border-radius: 9px; background: #fff; color: var(--navy-900); text-decoration: none; font-weight: 850; }
.topbar-home-link:hover { border-color: #8db8db; background: var(--blue-100); color: var(--blue-700); }
.topbar-separator { width: 1px; height: 20px; margin-inline: 2px; background: var(--line); }
.status-dot { width: 7px; height: 7px; border-radius: 50%; background: #36ad7d; box-shadow: 0 0 0 4px #e5f7ef; }
.account-button { display: grid; grid-template-columns: 37px auto 14px; gap: 10px; align-items: center; padding: 5px 7px 5px 5px; border: 0; border-radius: 12px; background: transparent; color: var(--ink); text-align: left; cursor: pointer; }
.account-button:hover { background: #f2f5f8; }
.account-button.is-guest { grid-template-columns: auto 14px; padding-left: 11px; }
.account-button.is-guest .avatar { display: none; }
.avatar { width: 37px; height: 37px; display: grid; place-items: center; border-radius: 50%; background: linear-gradient(145deg, var(--blue-600), var(--navy-900)); color: #fff; font-size: 11px; font-weight: 850; }
.account-button strong, .account-button small { display: block; }.account-button strong { font-size: 10px; }.account-button small { margin-top: 2px; color: var(--muted); font-size: 8px; }
.account-menu { position: absolute; right: clamp(28px, 4vw, 62px); top: 61px; width: 210px; overflow: hidden; border: 1px solid var(--line); border-radius: 12px; background: #fff; box-shadow: var(--shadow); }
.account-menu button, .account-menu a { width: 100%; display: block; padding: 12px 14px; border: 0; background: #fff; color: var(--ink); text-align: left; text-decoration: none; font-size: 10px; cursor: pointer; }
.account-menu button:hover, .account-menu a:hover { background: #f4f7fa; }
.access-pill { margin-left: 10px; padding: 5px 8px; border-radius: 999px; background: #eef6ff; color: var(--blue-700); text-decoration: none; font-size: 8px; font-weight: 850; }
.topbar-legacy-link { margin-left: 2px; color: #56687a; text-decoration: none; font-size: 8px; font-weight: 800; }
.topbar-legacy-link:hover { color: var(--blue-700); text-decoration: underline; text-underline-offset: 2px; }
.access-pill.is-plus { background: #f0ebff; color: #6248b3; }

.view { display: none; padding: 48px clamp(28px, 4vw, 62px) 76px; }
.view.is-visible { display: block; }
.welcome-row, .page-intro { display: flex; align-items: flex-end; justify-content: space-between; gap: 30px; margin-bottom: 30px; }
.welcome-row h1, .page-intro h1 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: clamp(36px, 4vw, 52px); font-weight: 500; letter-spacing: -0.035em; }
.welcome-row h1 + p, .page-intro h1 + p { max-width: 720px; margin: 10px 0 0; color: var(--muted); font-size: 13px; line-height: 1.6; }
.teachable-migration-note { margin: -4px 0 24px; padding: 15px 18px; display: flex; align-items: center; justify-content: space-between; gap: 20px; border: 1px solid #d7e2ea; border-radius: 14px; background: linear-gradient(110deg, #f1f8fd, #fff 72%); }
.teachable-migration-note[hidden] { display: none; }
.teachable-migration-note > div { display: flex; align-items: center; gap: 8px; }
.teachable-migration-note > div:first-child { align-items: flex-start; flex-direction: column; }
.teachable-migration-note strong { color: var(--navy-900); font-size: 11px; }
.teachable-migration-note span { max-width: 720px; color: var(--muted); font-size: 9px; line-height: 1.5; }
.teachable-migration-note a { color: var(--blue-700); font-size: 9px; font-weight: 850; text-decoration: none; white-space: nowrap; }
.teachable-migration-note a:hover { text-decoration: underline; text-underline-offset: 2px; }
.teachable-migration-note .is-secondary { color: var(--muted); font-weight: 750; }
.library-status { display: flex; align-items: center; gap: 11px; padding: 13px 16px; border: 1px solid var(--line); border-radius: 13px; background: #fff; white-space: nowrap; }
.status-mark { width: 31px; height: 31px; display: grid; place-items: center; border-radius: 9px; background: #e6f7ef; color: var(--green); font-weight: 900; }
.library-status small, .library-status strong { display: block; }.library-status small { color: var(--muted); font-size: 8px; text-transform: uppercase; letter-spacing: .08em; }.library-status strong { margin-top: 3px; color: var(--navy-900); font-size: 10px; }

.study-paths { display: grid; grid-template-columns: minmax(210px, .7fr) repeat(2, minmax(230px, 1fr)); gap: 14px; align-items: stretch; margin-bottom: 22px; }
.study-paths.is-single-path { grid-template-columns: minmax(210px, .7fr) minmax(300px, 1.35fr); }
.study-paths-intro { display: grid; align-content: center; padding: 4px 10px 4px 0; }.study-paths-intro h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 25px; font-weight: 500; line-height: 1.12; }
.study-path-card { display: grid; grid-template-columns: 46px minmax(0, 1fr) auto; gap: 13px; align-items: center; min-height: 82px; padding: 15px 17px; border: 1px solid var(--line); border-radius: 15px; background: #fff; color: var(--navy-900); text-align: left; box-shadow: 0 8px 24px rgba(8,33,61,.045); cursor: pointer; transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease; }
.study-path-card:hover { transform: translateY(-2px); border-color: #b5ccdf; box-shadow: 0 14px 30px rgba(8,33,61,.08); }.study-path-card > span:last-child { color: var(--blue-700); font-weight: 900; }.study-path-card strong, .study-path-card small { display: block; }.study-path-card strong { font-family: Georgia, serif; font-size: 17px; font-weight: 500; }.study-path-card small { margin-top: 4px; color: var(--muted); font-size: 8px; }
.study-path-icon { width: 46px; height: 46px; display: grid; place-items: center; border-radius: 12px; background: var(--blue-100); color: var(--blue-700); }.study-path-icon svg { width: 23px; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }.paper-path .study-path-icon { background: #eef2f7; color: var(--navy-800); }.paper-path > span:last-child { color: var(--navy-800); }

.continue-card { display: grid; grid-template-columns: minmax(360px, .9fr) minmax(0, 1.35fr); min-height: 286px; overflow: hidden; border-radius: 23px; background: #fff; box-shadow: var(--shadow); }
.continue-art { align-self: center; aspect-ratio: 16 / 9; margin: 22px 0 22px 22px; overflow: hidden; border-radius: 16px; background: #3299dc; box-shadow: 0 10px 25px rgba(8,33,61,.1); }
.continue-art > img, .continue-art > .igcse-course-art { display: block; width: 100%; height: 100%; object-fit: cover; }
.continue-art > .igcse-course-art { min-height: 100%; border-radius: 0; }
.continue-body { display: grid; grid-template-columns: minmax(0, 1fr) minmax(250px, .65fr); gap: 36px; align-items: center; padding: 38px; }
.continue-body h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: clamp(25px, 3vw, 36px); font-weight: 500; line-height: 1.14; }.continue-body h2 + p { margin: 10px 0 0; color: var(--muted); font-size: 11px; }
.continue-progress > div:first-child { display: flex; justify-content: space-between; color: var(--muted); font-size: 9px; font-weight: 750; }
.progress-track { height: 6px; overflow: hidden; margin-top: 10px; border-radius: 999px; background: #e6edf4; }.progress-track span { display: block; width: 0; height: 100%; border-radius: inherit; background: linear-gradient(90deg, #0b72ce, #42a6f3); transition: width .3s ease; }
.primary-button { min-height: 42px; display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 0 17px; border: 0; border-radius: 10px; background: var(--blue-700); color: #fff; font-size: 10px; font-weight: 850; text-decoration: none; cursor: pointer; }.primary-button:hover { background: #075495; }.continue-progress .primary-button { width: 100%; margin-top: 22px; }

.section-block { margin-top: 42px; }
.section-heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 20px; margin-bottom: 18px; }.section-heading h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 29px; font-weight: 500; }.text-button { padding: 8px 0; border: 0; background: transparent; color: var(--blue-700); font-size: 10px; font-weight: 850; cursor: pointer; }
.course-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.course-grid-large { margin-top: 8px; }
.course-card { --accent-a: #0c73c9; --accent-b: #073c6c; width: 100%; display: grid; grid-template-columns: 1fr; overflow: hidden; padding: 0; border: 1px solid var(--line); border-radius: 19px; background: #fff; color: var(--ink); text-align: left; box-shadow: 0 12px 34px rgba(8,33,61,.06); cursor: pointer; transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease; }
.course-card:hover { transform: translateY(-2px); border-color: #b5ccdf; box-shadow: 0 17px 40px rgba(8,33,61,.1); }
.course-card.is-large { grid-template-columns: 1fr; }
.accent-navy { --accent-a: #123b67; --accent-b: #061a34; }.accent-teal { --accent-a: #128891; --accent-b: #07515e; }.accent-indigo { --accent-a: #4451a6; --accent-b: #202b67; }.accent-red { --accent-a: #9f2f3d; --accent-b: #4f1522; }
.course-card-art { overflow: hidden; aspect-ratio: 16 / 9; background: #3299dc; }
.course-card-art img { display: block; width: 100%; height: 100%; object-fit: cover; }
.igcse-course-art { width: 100%; height: 100%; display: grid; align-content: center; justify-items: start; padding: clamp(24px, 4vw, 48px); background: radial-gradient(circle at 88% 18%, rgba(255,255,255,.16), transparent 28%), linear-gradient(145deg, #4f1522, #a62e3d); color: #fff; }
.igcse-course-art span, .igcse-course-art strong, .igcse-course-art small { display: block; }.igcse-course-art span { font-size: clamp(35px, 5vw, 62px); font-weight: 850; letter-spacing: -.04em; }.igcse-course-art strong { margin-top: 3px; font-family: Georgia, serif; font-size: clamp(18px, 2.3vw, 29px); font-weight: 500; }.igcse-course-art small { margin-top: 18px; font-size: 9px; font-weight: 800; letter-spacing: .12em; opacity: .72; text-transform: uppercase; }
.course-card-body { display: flex; flex-direction: column; min-width: 0; padding: 23px; }.course-card-meta { display: flex; justify-content: space-between; gap: 12px; color: var(--blue-700); font-size: 8px; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }.course-card-meta span:last-child { color: var(--muted); white-space: nowrap; }.course-card h3 { margin: 13px 0 8px; color: var(--navy-900); font-family: Georgia, serif; font-size: 23px; font-weight: 500; line-height: 1.15; }.course-card p { margin: 0; color: var(--muted); font-size: 10px; line-height: 1.55; }.course-card-progress { height: 4px; margin-top: auto; overflow: hidden; border-radius: 999px; background: #e9eef3; }.course-card-progress span { display: block; height: 100%; background: var(--accent-a); }.course-card-footer { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding-top: 11px; }.course-card-footer small { color: var(--muted); font-size: 8px; }.course-card-link { color: var(--blue-700); font-size: 9px; font-weight: 850; white-space: nowrap; }

.platform-summary { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 24px; overflow: hidden; border: 1px solid var(--line); border-radius: 17px; background: #fff; }.platform-summary article { padding: 21px; border-right: 1px solid var(--line); }.platform-summary article:last-child { border-right: 0; }.platform-summary strong, .platform-summary span { display: block; }.platform-summary strong { color: var(--navy-900); font-family: Georgia, serif; font-size: 27px; font-weight: 500; }.platform-summary span { margin-top: 4px; color: var(--muted); font-size: 9px; }
.page-intro { display: block; max-width: 840px; }

.past-paper-intro { margin-bottom: 24px; }.past-paper-course-tabs { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; }.past-paper-course-tabs.is-single-course { grid-template-columns: minmax(260px, 390px); }.past-paper-course-tab { min-width: 0; padding: 17px; border: 1px solid var(--line); border-radius: 14px; background: #fff; color: var(--ink); text-align: left; }.past-paper-course-tab.is-active { border-color: #b8cadd; background: #fff; box-shadow: 0 8px 24px rgba(8,33,61,.045); }.past-paper-course-tab span, .past-paper-course-tab strong, .past-paper-course-tab small { display: block; }.past-paper-course-tab span { color: var(--blue-700); font-size: 9px; font-weight: 900; letter-spacing: .09em; }.past-paper-course-tab strong { margin-top: 7px; overflow: hidden; color: var(--navy-900); font-family: Georgia, serif; font-size: 16px; font-weight: 500; text-overflow: ellipsis; white-space: nowrap; }.past-paper-course-tab small { margin-top: 6px; color: var(--muted); font-size: 8px; }
.past-paper-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin: 18px 0; padding: 14px 17px; border: 1px solid var(--line); border-radius: 13px; background: #fff; }.past-paper-toolbar > div strong, .past-paper-toolbar > div span { display: block; }.past-paper-toolbar > div strong { color: var(--navy-900); font-family: Georgia, serif; font-size: 18px; font-weight: 500; }.past-paper-toolbar > div span { margin-top: 3px; color: var(--muted); font-size: 8px; }.past-paper-toolbar label { display: flex; align-items: center; gap: 10px; color: var(--muted); font-size: 8px; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; }.past-paper-toolbar select { min-width: 155px; height: 36px; padding: 0 32px 0 11px; border: 1px solid #ccd8e3; border-radius: 9px; background: #fff; color: var(--navy-900); font-size: 10px; }
.past-paper-browser { display: grid; grid-template-columns: minmax(285px, .55fr) minmax(0, 1.45fr); gap: 20px; align-items: start; }.paper-catalog, .paper-solution-panel { min-width: 0; border: 1px solid var(--line); border-radius: 17px; background: #fff; box-shadow: 0 12px 34px rgba(8,33,61,.055); }.paper-catalog { position: sticky; top: 89px; overflow: hidden; }.paper-catalog-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 12px; padding: 18px 17px 13px; border-bottom: 1px solid var(--line); }.paper-catalog-head h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 21px; font-weight: 500; }.paper-catalog-head > span { color: var(--muted); font-size: 8px; white-space: nowrap; }.paper-set-list { max-height: calc(100vh - 230px); overflow-y: auto; padding: 8px; }.paper-set-card { width: 100%; display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 10px; align-items: center; padding: 12px; border: 0; border-radius: 10px; background: transparent; color: var(--ink); text-align: left; cursor: pointer; }.paper-set-card:hover { background: #f3f7fa; }.paper-set-card.is-active { background: var(--blue-100); }.paper-set-card small, .paper-set-card strong, .paper-set-card em { display: block; }.paper-set-card small { color: var(--blue-700); font-size: 8px; font-weight: 900; letter-spacing: .06em; text-transform: uppercase; }.paper-set-card strong { margin-top: 4px; color: var(--navy-900); font-size: 10px; }.paper-set-card em { margin-top: 4px; color: var(--muted); font-size: 7px; font-style: normal; }.paper-set-card i { color: var(--blue-700); font-style: normal; font-weight: 900; }.paper-free-badge { display: inline-flex; margin-left: 7px; padding: 3px 6px; border-radius: 999px; background: #e3f5ec; color: #176747; font-size: 6px; font-weight: 900; letter-spacing: .06em; line-height: 1; text-transform: uppercase; vertical-align: 1px; }
.paper-year-group + .paper-year-group { margin-top: 14px; padding-top: 14px; border-top: 1px solid var(--line); }.paper-year-heading { margin: 3px 8px 8px; color: var(--navy-900); font-family: Georgia, serif; font-size: 19px; font-weight: 500; }.paper-session-group + .paper-session-group { margin-top: 10px; }.paper-session-heading { margin: 0 8px 4px; color: var(--blue-700); font-size: 8px; font-weight: 900; letter-spacing: .08em; text-transform: uppercase; }
.paper-solution-panel { overflow: hidden; }.paper-player-shell { position: relative; aspect-ratio: 16 / 9; background: var(--navy-950); }.paper-player-shell iframe { display: block; width: 100%; height: 100%; border: 0; }.paper-solution-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 20px; padding: 22px 23px 18px; }.paper-solution-heading h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 28px; font-weight: 500; }.paper-solution-heading h2 + p { margin: 7px 0 0; color: var(--muted); font-size: 9px; }.paper-badge { flex: 0 0 auto; padding: 7px 9px; border-radius: 8px; background: var(--navy-900); color: #fff; font-size: 8px; font-weight: 900; letter-spacing: .07em; }.paper-question-panel { margin: 0 16px 16px; overflow: hidden; border: 1px solid var(--line); border-radius: 13px; }.paper-question-head { display: flex; justify-content: space-between; gap: 15px; padding: 13px 14px; border-bottom: 1px solid var(--line); background: #f8fafc; }.paper-question-head strong { color: var(--navy-900); font-size: 10px; }.paper-question-head span { color: var(--muted); font-size: 8px; }.paper-question-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px; max-height: 300px; overflow-y: auto; padding: 8px; }.paper-question-button { display: grid; grid-template-columns: 25px minmax(0, 1fr) auto; gap: 8px; align-items: center; min-width: 0; padding: 9px; border: 0; border-radius: 9px; background: transparent; color: var(--ink); text-align: left; cursor: pointer; }.paper-question-button:hover { background: #f3f7fa; }.paper-question-button.is-active { background: var(--blue-100); }.paper-question-button > span { width: 25px; height: 25px; display: grid; place-items: center; border-radius: 50%; background: #eef2f6; color: var(--muted); font-size: 7px; }.paper-question-button.is-active > span { background: var(--blue-600); color: #fff; }.paper-question-button strong { overflow: hidden; font-size: 8px; text-overflow: ellipsis; white-space: nowrap; }.paper-question-button small { color: var(--muted); font-size: 7px; white-space: nowrap; }

.course-hero { --accent-a: #0c73c9; --accent-b: #073c6c; margin: -48px calc(clamp(28px, 4vw, 62px) * -1) 26px; padding: 34px clamp(28px, 4vw, 62px) 27px; background: radial-gradient(circle at 85% 5%, rgba(255,255,255,.13), transparent 26%), linear-gradient(140deg, var(--accent-b), var(--accent-a)); color: #fff; }
.back-button { margin-bottom: 27px; padding: 0; border: 0; background: transparent; color: rgba(255,255,255,.72); font-size: 10px; font-weight: 750; cursor: pointer; }.course-hero-row { display: flex; align-items: flex-end; justify-content: space-between; gap: 30px; }.course-code { float: left; margin-right: 12px; padding: 6px 9px; border: 1px solid rgba(255,255,255,.32); border-radius: 7px; font-size: 9px; font-weight: 850; letter-spacing: .08em; }.course-hero .eyebrow { padding-top: 5px; color: #9ed4ff; }.course-hero h1 { clear: both; margin: 13px 0 7px; font-family: Georgia, serif; font-size: clamp(34px, 4vw, 48px); font-weight: 500; letter-spacing: -.03em; }.course-hero h1 + p { max-width: 680px; margin: 0; color: rgba(255,255,255,.72); font-size: 11px; }.hero-stat { text-align: right; }.hero-stat strong, .hero-stat span { display: block; }.hero-stat strong { font-family: Georgia, serif; font-size: 41px; font-weight: 500; }.hero-stat span { color: rgba(255,255,255,.68); font-size: 8px; letter-spacing: .1em; text-transform: uppercase; }.course-stats { display: flex; gap: 24px; margin-top: 24px; color: rgba(255,255,255,.74); font-size: 9px; }.course-stats strong { color: #fff; font-size: 11px; }.progress-track.light { margin-top: 17px; background: rgba(255,255,255,.17); }.progress-track.light span { background: #fff; }

.topic-strip { --topic-count: 5; display: grid; grid-template-columns: repeat(var(--topic-count), minmax(0, 1fr)); gap: 9px; margin-bottom: 24px; }.topic-button { min-width: 0; padding: 14px; border: 1px solid var(--line); border-radius: 12px; background: #fff; color: var(--ink); text-align: left; cursor: pointer; }.topic-button:hover { border-color: #b8c9da; }.topic-button.is-active { border-color: var(--blue-600); box-shadow: 0 0 0 2px rgba(11,114,206,.09); background: #eef7ff; }.topic-button span, .topic-button strong, .topic-button small { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }.topic-button span { color: var(--blue-700); font-size: 8px; font-weight: 900; letter-spacing: .08em; text-transform: uppercase; }.topic-button strong { margin-top: 5px; color: var(--navy-900); font-size: 10px; }.topic-button small { margin-top: 6px; color: var(--muted); font-size: 8px; }

.learning-layout { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(330px, .72fr); gap: 25px; align-items: start; }.player-column, .curriculum-panel { min-width: 0; }.video-shell { position: relative; overflow: hidden; aspect-ratio: 16/9; border-radius: 17px; background: #06172d; box-shadow: 0 18px 40px rgba(5,28,52,.15); }.video-shell iframe { display: block; width: 100%; height: 100%; border: 0; }.video-loading { position: absolute; inset: 0; display: grid; place-content: center; justify-items: center; gap: 10px; background: linear-gradient(145deg,#06172d,#0c3763); color: #b8ccdf; font-size: 10px; pointer-events: none; transition: opacity .25s; }.video-loading.is-hidden { opacity: 0; }.video-loading span { width: 28px; height: 28px; border: 3px solid rgba(255,255,255,.17); border-top-color: #62b9ff; border-radius: 50%; animation: spin 1s linear infinite; }@keyframes spin { to { transform: rotate(360deg); } }
.lesson-toolbar { display: flex; align-items: flex-start; justify-content: space-between; gap: 20px; padding: 23px 2px 18px; }.lesson-toolbar h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 29px; font-weight: 500; line-height: 1.18; }.lesson-toolbar h2 + p { margin: 7px 0 0; color: var(--muted); font-size: 10px; }.complete-button { min-height: 42px; flex: 0 0 auto; display: inline-flex; align-items: center; gap: 8px; padding: 0 14px; border: 1px solid #ccd7e1; border-radius: 10px; background: #fff; color: var(--navy-900); font-size: 10px; font-weight: 850; cursor: pointer; }.checkmark { width: 20px; height: 20px; display: grid; place-items: center; border: 1px solid #b8c5d2; border-radius: 50%; font-size: 9px; }.complete-button.is-complete { border-color: #b7e3d2; background: #eaf8f2; color: var(--green); }.complete-button.is-complete .checkmark { border-color: var(--green); background: var(--green); color: #fff; }
.lesson-details { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); overflow: hidden; border: 1px solid var(--line); border-radius: 13px; background: #fff; }.lesson-details div { padding: 14px; border-right: 1px solid var(--line); }.lesson-details div:last-child { border: 0; }.lesson-details small, .lesson-details strong { display: block; }.lesson-details small { color: var(--muted); font-size: 7px; letter-spacing: .1em; }.lesson-details strong { margin-top: 5px; overflow: hidden; color: var(--navy-900); font-size: 9px; text-overflow: ellipsis; white-space: nowrap; }
.lesson-practice { margin-top: 20px; overflow: hidden; border: 1px solid #cbdceb; border-radius: 16px; background: #fff; box-shadow: 0 12px 32px rgba(8,33,61,.055); }
.lesson-practice[hidden] { display: none; }
.lesson-practice-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 22px; padding: 21px 22px 17px; border-bottom: 1px solid var(--line); }
.lesson-practice-head h3 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 24px; font-weight: 500; }
.lesson-practice-head h3 + p { max-width: 670px; margin: 7px 0 0; color: var(--muted); font-size: 9px; line-height: 1.6; }
.lesson-practice-actions { flex: 0 0 auto; display: flex; align-items: center; gap: 9px; }
.practice-count { flex: 0 0 auto; padding: 7px 10px; border-radius: 999px; background: var(--blue-100); color: var(--blue-700); font-size: 8px; font-weight: 900; letter-spacing: .05em; text-transform: uppercase; }
.practice-expand-button { min-height: 31px; display: inline-flex; align-items: center; gap: 7px; padding: 0 11px; border: 1px solid #a9c6df; border-radius: 9px; background: #fff; color: var(--blue-700); font-size: 9px; font-weight: 850; cursor: pointer; }
.practice-expand-button:hover { border-color: var(--blue-600); background: var(--blue-100); }
.practice-expand-button:focus-visible { outline: 3px solid rgba(11,114,206,.22); outline-offset: 2px; }
.practice-frame-wrap { height: 660px; overflow: hidden; transition: height .18s ease; }
.practice-frame-wrap iframe { display: block; width: 100%; height: 100%; border: 0; background: #f7f3eb; }
body.practice-expanded { overflow: hidden; }
body.practice-expanded::before { content: ""; position: fixed; z-index: 119; inset: 0; background: rgba(4,22,44,.58); backdrop-filter: blur(4px); }
.lesson-practice.is-expanded { position: fixed; z-index: 120; inset: clamp(10px, 3vh, 28px) clamp(10px, 3vw, 42px); display: grid; grid-template-rows: auto minmax(0, 1fr); margin: 0; overflow: hidden; border-color: #9ebed9; border-radius: 18px; background: #fff; box-shadow: 0 28px 90px rgba(4,22,44,.42); }
.lesson-practice.is-expanded .lesson-practice-head { position: relative; z-index: 2; min-height: 0; align-items: center; padding: 15px 20px; background: #fff; box-shadow: 0 8px 22px rgba(8,33,61,.08); }
.lesson-practice.is-expanded .practice-frame-wrap { min-height: 0; height: auto !important; overflow: hidden; }
.lesson-practice.is-expanded .practice-frame-wrap iframe { overscroll-behavior: contain; }
.lesson-navigation { display: flex; justify-content: space-between; margin-top: 18px; }.lesson-navigation button { padding: 10px 13px; border: 1px solid var(--line); border-radius: 9px; background: #fff; color: var(--navy-900); font-size: 9px; font-weight: 800; cursor: pointer; }.lesson-navigation button:disabled { opacity: .38; cursor: default; }

.curriculum-panel { position: sticky; top: 89px; max-height: calc(100vh - 115px); overflow: hidden; border: 1px solid var(--line); border-radius: 16px; background: #fff; box-shadow: 0 12px 32px rgba(8,33,61,.06); }.curriculum-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 18px; padding: 19px 18px 14px; }.curriculum-head h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 22px; font-weight: 500; }.curriculum-head > span { color: var(--muted); font-size: 8px; white-space: nowrap; }.lesson-search { position: relative; display: block; margin: 0 13px 11px; }.lesson-search svg { position: absolute; left: 10px; top: 10px; width: 16px; fill: none; stroke: #8493a3; stroke-width: 1.7; }.lesson-search input { width: 100%; height: 36px; padding: 0 11px 0 32px; border: 1px solid var(--line); border-radius: 9px; background: #fbfcfd; outline: none; font-size: 10px; }.lesson-search input:focus { border-color: #77b7ee; box-shadow: 0 0 0 3px #e9f5ff; }.lesson-list { max-height: calc(100vh - 246px); overflow-y: auto; padding: 0 8px 12px; }.lesson-group-label { padding: 13px 10px 6px; color: #7d8c9d; font-size: 7px; font-weight: 900; letter-spacing: .12em; text-transform: uppercase; }.lesson-item { width: 100%; display: grid; grid-template-columns: 26px minmax(0, 1fr); gap: 10px; align-items: center; padding: 9px; border: 0; border-radius: 9px; background: transparent; text-align: left; cursor: pointer; }.lesson-item:hover { background: #f4f7fa; }.lesson-item.is-active { background: var(--blue-100); }.lesson-state { width: 26px; height: 26px; display: grid; place-items: center; border: 1px solid #d1dbe5; border-radius: 50%; color: #8493a2; font-size: 7px; }.lesson-item.is-active .lesson-state { border-color: var(--blue-600); background: var(--blue-600); color: #fff; }.lesson-item.is-complete:not(.is-active) .lesson-state { border-color: var(--green); background: #e9f8f1; color: var(--green); }.lesson-item strong, .lesson-item small { display: block; }.lesson-item strong { overflow: hidden; color: var(--ink); font-size: 9px; text-overflow: ellipsis; white-space: nowrap; }.lesson-item small { margin-top: 3px; color: #8d9aa8; font-size: 7px; }.no-results { padding: 25px 14px; color: var(--muted); text-align: center; font-size: 10px; }

.progress-course-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }.progress-course-card { --accent-a: #0c73c9; --accent-b: #073c6c; padding: 25px; border: 1px solid var(--line); border-top: 4px solid var(--accent-a); border-radius: 17px; background: #fff; box-shadow: 0 10px 28px rgba(8,33,61,.05); }.progress-course-head { display: flex; align-items: flex-start; justify-content: space-between; }.progress-course-head > span { padding: 6px 8px; border-radius: 7px; background: var(--accent-a); color: #fff; font-size: 8px; font-weight: 850; }.progress-course-head div { text-align: right; }.progress-course-head strong, .progress-course-head small { display: block; }.progress-course-head strong { color: var(--navy-900); font-family: Georgia, serif; font-size: 28px; font-weight: 500; }.progress-course-head small { color: var(--muted); font-size: 7px; text-transform: uppercase; letter-spacing: .09em; }.progress-course-card h2 { margin: 13px 0 5px; color: var(--navy-900); font-family: Georgia, serif; font-size: 22px; font-weight: 500; }.progress-course-card > p { margin: 0; color: var(--muted); font-size: 9px; }.topic-progress-list { display: grid; gap: 9px; margin: 22px 0; }.topic-progress-row { display: grid; grid-template-columns: 54px 1fr 34px; gap: 9px; align-items: center; color: var(--muted); font-size: 8px; }.topic-progress-row > div { height: 4px; overflow: hidden; border-radius: 999px; background: #e7edf3; }.topic-progress-row i { display: block; height: 100%; background: var(--accent-a); }.topic-progress-row small { text-align: right; }.progress-course-card .primary-button { width: 100%; background: var(--accent-a); }

.prototype-dialog { position: relative; width: min(460px, calc(100vw - 32px)); padding: 38px; border: 0; border-radius: 20px; background: var(--paper); color: var(--ink); box-shadow: 0 30px 80px rgba(4,22,44,.25); }.prototype-dialog::backdrop { background: rgba(4,21,41,.62); backdrop-filter: blur(5px); }.prototype-dialog.small { width: min(390px, calc(100vw - 32px)); text-align: center; }.prototype-dialog > img { width: 155px; margin-bottom: 28px; }.prototype-dialog h2 { margin: 0; color: var(--navy-900); font-family: Georgia, serif; font-size: 31px; font-weight: 500; }.prototype-dialog h2 + p { margin: 10px 0 23px; color: var(--muted); font-size: 11px; line-height: 1.6; }.prototype-dialog form > label { display: grid; gap: 6px; margin-top: 13px; color: var(--navy-900); font-size: 9px; font-weight: 800; text-align: left; }.prototype-dialog input { height: 44px; padding: 0 12px; border: 1px solid #d4dee7; border-radius: 9px; background: #fff; outline: none; font-size: 11px; }.dialog-close { position: absolute; right: 13px; top: 13px; width: 33px; height: 33px; border: 0; border-radius: 50%; background: #e9eef3; color: #627184; font-size: 19px; cursor: pointer; }.primary-button.full { width: 100%; margin-top: 18px; }.dialog-note { display: block; margin-top: 14px; color: var(--muted); font-size: 8px; }.help-icon.large { width: 48px; height: 48px; margin: 0 auto 15px; background: var(--blue-100); color: var(--blue-700); font-size: 17px; }
.toast { position: fixed; z-index: 80; left: 50%; bottom: 24px; transform: translate(-50%, 18px); padding: 11px 16px; border-radius: 9px; background: var(--navy-950); color: #fff; box-shadow: var(--shadow); font-size: 10px; opacity: 0; pointer-events: none; transition: .22s ease; }.toast.is-visible { opacity: 1; transform: translate(-50%, 0); }

@media (max-width: 1120px) {
  :root { --sidebar-width: 225px; }
  .study-paths { grid-template-columns: repeat(2, minmax(0, 1fr)); }.study-paths-intro { grid-column: 1 / -1; }
  .continue-body { grid-template-columns: 1fr; gap: 24px; }
  .course-card { grid-template-columns: 125px minmax(0, 1fr); }
  .course-card.is-large { grid-template-columns: 150px minmax(0, 1fr); }
  .learning-layout { grid-template-columns: minmax(0, 1.3fr) minmax(300px, .75fr); }
}

@media (max-width: 920px) {
  .app-shell { display: block; }
  .sidebar { position: fixed; top: 0; left: 0; width: min(290px, 84vw); height: 100vh; transform: translateX(-102%); transition: transform .25s ease; box-shadow: 20px 0 60px rgba(4,25,50,.18); }
  .sidebar.is-open { transform: translateX(0); }
  .sidebar-scrim { position: fixed; z-index: 25; inset: 0; display: block; background: rgba(5,24,47,.46); opacity: 0; pointer-events: none; transition: opacity .25s; }.sidebar-scrim.is-open { opacity: 1; pointer-events: auto; }
  .mobile-close, .menu-button { display: grid; }
  .topbar { height: 64px; padding-inline: 20px; }.topbar-context { display: flex; }.topbar-context > :not(.topbar-home-link) { display: none; }.account-menu { right: 20px; top: 57px; }
  .view { padding: 34px 20px 58px; }
  .course-hero { margin: -34px -20px 24px; padding-inline: 20px; }
  .continue-card { grid-template-columns: 1fr; }.continue-art { min-height: 0; margin: 18px 18px 0; aspect-ratio: 16 / 9; }
  .learning-layout { grid-template-columns: 1fr; }.curriculum-panel { position: static; max-height: none; }.lesson-list { max-height: 520px; }
  .past-paper-course-tabs { grid-template-columns: repeat(2, minmax(0, 1fr)); }.past-paper-browser { grid-template-columns: 1fr; }.paper-catalog { position: static; }.paper-set-list { max-height: 360px; }
  .topic-strip { overflow-x: auto; grid-template-columns: repeat(var(--topic-count), minmax(150px, 1fr)); padding-bottom: 3px; }
}

@media (max-width: 680px) {
  .teachable-migration-note, .teachable-migration-note > div:last-child { align-items: flex-start; flex-direction: column; }
  .teachable-migration-note > div:last-child { gap: 6px; }
  .welcome-row { display: block; }.library-status { display: none; }.welcome-row h1, .page-intro h1 { font-size: 36px; }
  .study-paths { grid-template-columns: 1fr; }.study-paths-intro { padding-bottom: 3px; }.study-paths-intro h2 { font-size: 22px; }
  .continue-body { padding: 27px; }.course-grid, .progress-course-grid { grid-template-columns: 1fr; }.course-card, .course-card.is-large { grid-template-columns: 1fr; min-height: 0; }.course-card-body { min-height: 240px; padding: 20px; }.course-card h3 { font-size: 20px; }
  .platform-summary { grid-template-columns: 1fr; }.platform-summary article { border-right: 0; border-bottom: 1px solid var(--line); }.platform-summary article:last-child { border-bottom: 0; }
  .account-button { grid-template-columns: 37px 14px; }.account-button > span:nth-child(2) { display: none; }
  .course-hero-row { align-items: flex-start; }.hero-stat { display: none; }.course-stats { gap: 14px; flex-wrap: wrap; }
  .lesson-toolbar { display: grid; }.complete-button { width: 100%; justify-content: center; }.lesson-details { grid-template-columns: 1fr; }.lesson-details div { border-right: 0; border-bottom: 1px solid var(--line); }.lesson-details div:last-child { border-bottom: 0; }
  .lesson-practice-head { display: grid; padding: 18px; }.lesson-practice-actions { justify-self: start; flex-wrap: wrap; }.practice-frame-wrap { height: 760px; }
  .lesson-practice.is-expanded { inset: 6px; border-radius: 13px; }
  .lesson-practice.is-expanded .lesson-practice-head { padding: 13px 14px; }
  .past-paper-course-tabs { display: flex; overflow-x: auto; padding-bottom: 3px; }.past-paper-course-tabs.is-single-course { display: grid; grid-template-columns: 1fr; }.past-paper-course-tab { flex: 0 0 210px; }.past-paper-toolbar { align-items: stretch; flex-direction: column; }.past-paper-toolbar label { justify-content: space-between; }.past-paper-toolbar select { flex: 1; }.paper-question-list { grid-template-columns: 1fr; }.paper-solution-heading { padding: 18px; }.paper-solution-heading h2 { font-size: 23px; }
  .prototype-dialog { padding: 34px 23px 25px; }
}

.lesson-item.is-locked { opacity: 1; }
.lesson-item.is-locked .lesson-state { border-color: #cfc5ef; background: #f0ecff; color: #5b46ac; font-size: 12px; font-weight: 900; }
.lesson-item.is-locked small { color: #6656a5; font-weight: 800; }
.complete-button.is-plus-locked { border-color: #cfc5ef; background: #f5f2ff; color: #5944aa; }
.complete-button.is-plus-locked .checkmark { border-color: #9a89d8; background: #6550b9; color: #fff; }
.video-loading.is-plus-locked { padding: 28px; text-align: center; pointer-events: auto; }
.video-loading.is-plus-locked > span { width: 46px; height: 46px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.22); background: rgba(255,255,255,.1); color: #fff; font-size: 25px; font-weight: 700; animation: none; }
.video-loading.is-plus-locked strong { color: #fff; font-size: clamp(16px, 2vw, 22px); }
.video-loading.is-plus-locked p { max-width: 380px; margin: 0; color: #bdd3e5; font-size: 11px; line-height: 1.5; }
.plus-upgrade-dialog .eyebrow { margin: 15px 0 8px; }
.plus-mark { width: 54px; height: 54px; display: grid; place-items: center; margin: 0 auto; border-radius: 18px; background: linear-gradient(145deg, #8064dc, #523ba7); color: #fff; box-shadow: 0 12px 25px rgba(82,59,167,.23); font-size: 30px; font-weight: 700; }
.dialog-secondary-button { margin-top: 13px; padding: 8px 12px; border: 0; background: transparent; color: var(--muted); font-size: 9px; font-weight: 800; cursor: pointer; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .001ms !important; transition-duration: .001ms !important; }
}
.course-card.is-sample .course-card-art { position: relative; }
.course-card.is-sample .course-card-art::after { content: "Free samples"; position: absolute; right: 12px; top: 12px; padding: 6px 9px; border-radius: 999px; background: rgba(6,23,45,.9); color: white; font-size: 8px; font-weight: 850; letter-spacing: .05em; text-transform: uppercase; }
.video-loading .primary-button { margin-top: 10px; text-decoration: none; pointer-events: auto; }