:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --surface-2: #eef2f7;
  --ink: #14243a;
  --muted: #66758a;
  --line: #dce3ec;
  --navy: #10243f;
  --blue: #3567e9;
  --blue-dark: #214bb5;
  --coral: #ff795d;
  --mint: #5fd5b4;
  --yellow: #ffc857;
  --violet: #8668df;
  --green: #2da579;
  --shadow: 0 14px 42px rgba(24, 45, 74, .09);
  --radius: 18px;
  --sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { min-width: 320px; margin: 0; color: var(--ink); background: var(--bg); font: 14px/1.5 var(--sans); -webkit-font-smoothing: antialiased; }
button, input, select, textarea { font: inherit; }
button { color: inherit; }
button:not(:disabled), a { cursor: pointer; }
button:disabled { cursor: not-allowed; opacity: .5; }
a { color: inherit; text-decoration: none; }
::selection { color: #fff; background: var(--blue); }

.sr-only { position: absolute !important; width: 1px !important; height: 1px !important; padding: 0 !important; margin: -1px !important; overflow: hidden !important; clip: rect(0, 0, 0, 0) !important; white-space: nowrap !important; border: 0 !important; }
.skip-link { position: fixed; z-index: 999; top: 12px; left: 12px; padding: 10px 14px; color: #fff; background: var(--navy); border-radius: 9px; transform: translateY(-150%); }
.skip-link:focus { transform: translateY(0); }

.app-shell { min-height: 100vh; display: flex; }
.sidebar { position: fixed; z-index: 30; inset: 0 auto 0 0; width: 238px; display: flex; flex-direction: column; padding: 25px 16px 18px; color: #eef4fb; background: var(--navy); border-right: 1px solid rgba(255,255,255,.06); }
.brand { display: flex; align-items: center; gap: 11px; margin: 0 6px 31px; }
.brand-mark { position: relative; width: 40px; height: 40px; flex: 0 0 40px; display: block; background: #fff; border-radius: 12px; }
.brand-mark i { position: absolute; bottom: 9px; width: 5px; background: var(--blue); border-radius: 5px 5px 1px 1px; transform: skew(-10deg); }
.brand-mark i:nth-child(1) { left: 10px; height: 13px; background: var(--coral); }
.brand-mark i:nth-child(2) { left: 18px; height: 22px; background: var(--blue); }
.brand-mark i:nth-child(3) { left: 26px; height: 29px; background: var(--mint); }
.brand > span:last-child { display: grid; gap: 1px; }
.brand b { font-size: 16px; letter-spacing: .13em; }
.brand small { color: #91a1b5; font-size: 9px; }

.main-nav { display: grid; gap: 3px; }
.main-nav p { margin: 20px 12px 7px; color: #687b92; font-size: 9px; font-weight: 800; letter-spacing: .16em; text-transform: uppercase; }
.main-nav a, .main-nav button { width: 100%; min-height: 44px; display: grid; grid-template-columns: 24px 1fr auto; align-items: center; gap: 9px; padding: 8px 11px; color: #aebbc9; background: transparent; border: 0; border-radius: 10px; text-align: left; transition: color .18s, background .18s, transform .18s; }
.main-nav a:hover, .main-nav button:hover { color: #fff; background: rgba(255,255,255,.07); transform: translateX(2px); }
.main-nav a.active { color: #10243f; background: #fff; }
.main-nav span { font-size: 18px; text-align: center; }
.main-nav b { font-size: 12px; font-weight: 650; }
.main-nav em { min-width: 22px; padding: 3px 6px; color: #10243f; background: var(--mint); border-radius: 999px; font-size: 9px; font-style: normal; font-weight: 850; text-align: center; }
.main-nav a.active em { color: #fff; background: var(--blue); }

.streak-card { margin-top: auto; padding: 15px; background: rgba(255,255,255,.065); border: 1px solid rgba(255,255,255,.08); border-radius: 14px; }
.streak-card > span { float: left; width: 34px; height: 34px; display: grid; place-items: center; margin-right: 9px; color: #10243f; background: var(--yellow); border-radius: 10px; }
.streak-card > div:nth-child(2) { display: grid; gap: 2px; }
.streak-card b { font-size: 11px; }
.streak-card b i { font-style: normal; }
.streak-card small { color: #8fa0b4; font-size: 8px; }
.streak-week { clear: both; display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; padding-top: 13px; }
.streak-week i { aspect-ratio: 1; display: grid; place-items: center; color: #70839b; background: rgba(255,255,255,.05); border-radius: 50%; font-size: 7px; font-style: normal; }
.streak-week i.done { color: #10243f; background: var(--mint); }
.streak-week i.today { color: #fff; border: 1px solid var(--coral); }
.profile-card { display: grid; grid-template-columns: 34px 1fr auto; align-items: center; gap: 9px; margin-top: 14px; padding: 10px 5px 0; }
.avatar, .top-avatar { display: grid; place-items: center; color: #fff; background: linear-gradient(145deg, #9a78f0, #4e67de); border-radius: 50%; font-size: 9px; font-weight: 850; }
.avatar { width: 34px; height: 34px; }
.profile-card div { display: grid; gap: 1px; }
.profile-card b { font-size: 10px; }
.profile-card small { color: #8193a9; font-size: 8px; }
.profile-card button { color: #8092a6; background: none; border: 0; }

.main-shell { width: calc(100% - 238px); min-width: 0; margin-left: 238px; }
.topbar { position: sticky; z-index: 20; top: 0; height: 72px; display: grid; grid-template-columns: 1fr minmax(290px, 510px) 1fr; align-items: center; gap: 20px; padding: 0 28px; background: color-mix(in srgb, var(--bg) 93%, transparent); border-bottom: 1px solid var(--line); backdrop-filter: blur(16px); }
.page-context { display: grid; gap: 1px; }
.page-context small { color: var(--blue); font-size: 8px; font-weight: 850; letter-spacing: .13em; }
.page-context b { font-size: 12px; }
.global-search { height: 42px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 10px; padding: 0 12px; color: var(--muted); background: var(--surface); border: 1px solid var(--line); border-radius: 11px; box-shadow: 0 2px 0 rgba(19,39,66,.03); }
.global-search:focus-within { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(53,103,233,.1); }
.global-search input { min-width: 0; width: 100%; color: var(--ink); background: transparent; border: 0; outline: 0; font-size: 11px; }
kbd { padding: 3px 6px; color: var(--muted); background: var(--surface-2); border: 1px solid var(--line); border-radius: 5px; font: 700 8px/1.2 var(--sans); }
.top-actions { display: flex; align-items: center; justify-content: flex-end; gap: 8px; }
.icon-button, .top-avatar { width: 38px; height: 38px; border: 1px solid var(--line); }
.icon-button { display: grid; place-items: center; background: var(--surface); border-radius: 10px; }
.icon-button:hover { border-color: var(--blue); }
.menu-button { display: none; }
.top-avatar { border: 0; }
.notification-button { position: relative; }
.notification-button i { position: absolute; top: 8px; right: 8px; width: 7px; height: 7px; background: var(--coral); border: 2px solid var(--surface); border-radius: 50%; }

#workspace { min-height: calc(100vh - 72px); outline: 0; }
.view-page { padding: 31px 28px 62px; }
.page-shell { width: 100%; max-width: 1420px; margin: 0 auto; }
.page-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 22px; margin-bottom: 25px; }
.title-block { max-width: 740px; }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; margin-bottom: 8px; color: var(--blue); font-size: 9px; font-weight: 850; letter-spacing: .14em; text-transform: uppercase; }
.eyebrow::before { content: ""; width: 18px; height: 2px; background: currentColor; }
.title-block h1 { margin: 0; font-size: clamp(31px, 4vw, 48px); line-height: 1.05; letter-spacing: -.045em; }
.title-block p { margin: 10px 0 0; color: var(--muted); font-size: 11px; line-height: 1.6; }
.head-actions { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px; }
.primary-button, .secondary-button, .ghost-button, .complete-button { min-height: 41px; display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 0 16px; border-radius: 10px; font-size: 11px; font-weight: 800; transition: transform .18s, background .18s, box-shadow .18s; }
.primary-button { color: #fff; background: var(--blue); border: 1px solid var(--blue); box-shadow: 0 7px 18px rgba(53,103,233,.2); }
.primary-button:hover { background: var(--blue-dark); transform: translateY(-1px); }
.secondary-button { color: var(--ink); background: var(--surface); border: 1px solid var(--line); }
.secondary-button:hover { border-color: var(--blue); }
.ghost-button { padding-inline: 10px; color: var(--muted); background: transparent; border: 1px solid transparent; }
.ghost-button:hover { color: var(--ink); background: var(--surface-2); }
.complete-button { color: #fff; background: var(--green); border: 1px solid var(--green); }
.complete-button.completed { color: var(--green); background: transparent; }

.welcome-hero { position: relative; overflow: hidden; display: grid; grid-template-columns: 1.25fr .75fr; min-height: 236px; margin-bottom: 20px; padding: 34px 38px; color: #fff; background: linear-gradient(118deg, #163f78 0%, #2d60cf 58%, #7866dd 100%); border-radius: 24px; box-shadow: 0 18px 45px rgba(37,76,151,.2); }
.welcome-hero::before, .welcome-hero::after { content: ""; position: absolute; border: 1px solid rgba(255,255,255,.13); border-radius: 50%; }
.welcome-hero::before { width: 310px; height: 310px; right: -90px; top: -125px; }
.welcome-hero::after { width: 210px; height: 210px; right: 85px; bottom: -145px; }
.hero-copy { position: relative; z-index: 2; align-self: center; }
.hero-copy > span { color: #bdebdc; font-size: 9px; font-weight: 850; letter-spacing: .15em; }
.hero-copy h2 { max-width: 650px; margin: 11px 0 12px; font-size: clamp(27px, 3.4vw, 45px); line-height: 1.08; letter-spacing: -.045em; }
.hero-copy p { max-width: 570px; margin: 0 0 19px; color: #d6e3f8; font-size: 11px; line-height: 1.65; }
.hero-copy .primary-button { color: #10243f; background: #fff; border-color: #fff; box-shadow: none; }
.hero-visual { position: relative; z-index: 1; min-height: 175px; align-self: center; }
.hero-orbit { position: absolute; inset: 0; }
.hero-orbit > i { position: absolute; display: grid; place-items: center; font-style: normal; box-shadow: 0 13px 30px rgba(15,33,64,.22); }
.hero-orbit .tile-main { right: 44px; top: 21px; width: 112px; height: 122px; color: #10243f; background: var(--mint); border-radius: 24px; font-size: 42px; transform: rotate(7deg); }
.hero-orbit .tile-small { right: 145px; bottom: 4px; width: 63px; height: 63px; color: #fff; background: var(--coral); border-radius: 17px; font-size: 24px; transform: rotate(-8deg); }
.hero-orbit .tile-dot { right: 4px; bottom: 12px; width: 55px; height: 55px; color: #10243f; background: var(--yellow); border-radius: 50%; font-size: 19px; }

.quick-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-bottom: 23px; }
.quick-stat { min-height: 96px; display: grid; grid-template-columns: 44px 1fr; align-items: center; gap: 12px; padding: 16px; background: var(--surface); border: 1px solid var(--line); border-radius: 15px; }
.quick-stat > span { width: 44px; height: 44px; display: grid; place-items: center; color: var(--stat); background: color-mix(in srgb, var(--stat) 13%, transparent); border-radius: 12px; font-size: 20px; }
.quick-stat div { display: grid; gap: 2px; }
.quick-stat strong { font-size: 21px; letter-spacing: -.03em; }
.quick-stat small { color: var(--muted); font-size: 9px; }

.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 18px; margin: 26px 0 14px; }
.section-head h2 { margin: 0; font-size: 20px; letter-spacing: -.025em; }
.section-head p { margin: 4px 0 0; color: var(--muted); font-size: 9px; }
.section-head a, .section-head button { color: var(--blue); background: transparent; border: 0; font-size: 9px; font-weight: 800; }

.learning-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.learning-card { overflow: hidden; display: grid; grid-template-columns: 115px 1fr; min-height: 150px; background: var(--surface); border: 1px solid var(--line); border-radius: 17px; transition: transform .2s, box-shadow .2s; }
.learning-card:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.mini-cover { position: relative; overflow: hidden; display: grid; place-items: center; color: #fff; background: linear-gradient(145deg, var(--cover), var(--cover2)); }
.mini-cover::before { content: ""; position: absolute; width: 96px; height: 96px; border: 1px solid rgba(255,255,255,.24); border-radius: 50%; transform: translate(33px,-43px); }
.mini-cover::after { content: ""; position: absolute; width: 53px; height: 53px; background: rgba(255,255,255,.14); border-radius: 14px; transform: rotate(20deg) translate(-28px,39px); }
.mini-cover span { position: relative; z-index: 1; font-size: 33px; }
.learning-card-body { min-width: 0; padding: 15px 14px; }
.course-kicker { display: flex; align-items: center; gap: 6px; color: var(--blue); font-size: 8px; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.course-kicker i { width: 6px; height: 6px; background: currentColor; border-radius: 50%; }
.learning-card h3 { margin: 7px 0 5px; overflow: hidden; font-size: 12px; text-overflow: ellipsis; white-space: nowrap; }
.learning-card p { margin: 0; color: var(--muted); font-size: 8px; }
.progress-line { height: 5px; overflow: hidden; margin: 14px 0 7px; background: var(--surface-2); border-radius: 999px; }
.progress-line i { display: block; height: 100%; background: var(--blue); border-radius: inherit; }
.progress-meta { display: flex; justify-content: space-between; color: var(--muted); font-size: 8px; }
.progress-meta b { color: var(--ink); }

.course-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 15px; }
.course-card { position: relative; overflow: hidden; background: var(--surface); border: 1px solid var(--line); border-radius: 18px; transition: transform .2s, box-shadow .2s; }
.course-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.course-cover { position: relative; overflow: hidden; height: 148px; display: grid; place-items: center; color: #fff; background: linear-gradient(135deg, var(--cover), var(--cover2)); }
.course-cover::before { content: ""; position: absolute; width: 155px; height: 155px; border: 1px solid rgba(255,255,255,.24); border-radius: 50%; transform: translate(68px,-63px); }
.course-cover::after { content: ""; position: absolute; width: 92px; height: 92px; background: rgba(255,255,255,.13); border-radius: 25px; transform: rotate(28deg) translate(-65px,47px); }
.course-icon { position: relative; z-index: 1; width: 65px; height: 65px; display: grid; place-items: center; background: rgba(255,255,255,.18); border: 1px solid rgba(255,255,255,.32); border-radius: 20px; font-size: 31px; backdrop-filter: blur(8px); }
.bookmark-button { position: absolute; z-index: 3; top: 10px; right: 10px; width: 32px; height: 32px; display: grid; place-items: center; color: #fff; background: rgba(15,33,59,.28); border: 1px solid rgba(255,255,255,.28); border-radius: 9px; backdrop-filter: blur(8px); }
.bookmark-button.saved { color: #10243f; background: var(--yellow); border-color: var(--yellow); }
.course-card-body { padding: 15px; }
.course-card-body h3 { min-height: 36px; margin: 8px 0 7px; font-size: 13px; line-height: 1.35; letter-spacing: -.015em; }
.course-card-body > p { margin: 0; color: var(--muted); font-size: 9px; }
.course-card-meta { display: flex; align-items: center; justify-content: space-between; gap: 7px; margin-top: 12px; padding-top: 11px; border-top: 1px solid var(--line); color: var(--muted); font-size: 8px; }
.rating { color: #b4730f; font-weight: 800; }
.course-card-actions { display: flex; gap: 7px; margin-top: 12px; }
.course-card-actions button { flex: 1; min-height: 35px; padding: 0 9px; border-radius: 8px; font-size: 9px; font-weight: 800; }
.course-card-actions .view-course { color: var(--ink); background: var(--surface-2); border: 1px solid var(--line); }
.course-card-actions .enroll-course, .course-card-actions .continue-course { color: #fff; background: var(--blue); border: 1px solid var(--blue); }
.course-card-actions .enrolled-label { color: var(--green); background: color-mix(in srgb, var(--green) 11%, transparent); border: 1px solid color-mix(in srgb, var(--green) 30%, var(--line)); }

.filter-bar { display: flex; align-items: center; justify-content: space-between; gap: 13px; margin-bottom: 17px; padding: 11px; background: var(--surface); border: 1px solid var(--line); border-radius: 14px; }
.filter-group { display: flex; flex: 1; flex-wrap: wrap; gap: 8px; }
.filter-search { position: relative; min-width: min(100%, 260px); max-width: 370px; flex: 1; }
.filter-search span { position: absolute; left: 11px; top: 50%; color: var(--muted); transform: translateY(-50%); }
.filter-search input, .filter-select { height: 39px; color: var(--ink); background: var(--bg); border: 1px solid var(--line); border-radius: 9px; outline: 0; }
.filter-search input { width: 100%; padding: 0 11px 0 34px; }
.filter-select { min-width: 125px; padding: 0 29px 0 10px; }
.filter-search input:focus, .filter-select:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(53,103,233,.1); }
.result-count { color: var(--muted); font-size: 9px; white-space: nowrap; }

.empty-state { grid-column: 1 / -1; padding: 62px 24px; background: var(--surface); border: 1px solid var(--line); border-radius: 18px; text-align: center; }
.empty-state > span { width: 66px; height: 66px; display: grid; place-items: center; margin: 0 auto 17px; color: var(--blue); background: rgba(53,103,233,.1); border-radius: 20px; font-size: 28px; }
.empty-state h3 { margin: 0; font-size: 18px; }
.empty-state p { max-width: 390px; margin: 7px auto 17px; color: var(--muted); font-size: 10px; line-height: 1.6; }

.learning-page-grid { display: grid; grid-template-columns: minmax(0,1.55fr) minmax(270px,.55fr); gap: 17px; align-items: start; }
.learning-list { display: grid; gap: 12px; }
.learning-list-card { display: grid; grid-template-columns: 145px 1fr auto; align-items: center; gap: 17px; padding: 13px; background: var(--surface); border: 1px solid var(--line); border-radius: 16px; }
.learning-list-card .mini-cover { height: 105px; border-radius: 12px; }
.learning-list-card h3 { margin: 7px 0 5px; font-size: 14px; }
.learning-list-card p { margin: 0; color: var(--muted); font-size: 9px; }
.learning-list-card .list-progress { min-width: 205px; }
.learning-list-card .primary-button { min-height: 36px; margin-top: 9px; padding-inline: 12px; font-size: 9px; }
.activity-panel { background: var(--surface); border: 1px solid var(--line); border-radius: 17px; }
.activity-panel h3 { margin: 0; padding: 17px 18px; border-bottom: 1px solid var(--line); font-size: 14px; }
.activity-list { display: grid; padding: 8px 17px 16px; }
.activity-item { display: grid; grid-template-columns: 31px 1fr; gap: 10px; padding: 11px 0; border-bottom: 1px solid var(--line); }
.activity-item:last-child { border-bottom: 0; }
.activity-item > span { width: 31px; height: 31px; display: grid; place-items: center; color: var(--blue); background: rgba(53,103,233,.09); border-radius: 9px; font-size: 13px; }
.activity-item div { display: grid; gap: 3px; }
.activity-item b { font-size: 9px; line-height: 1.35; }
.activity-item small { color: var(--muted); font-size: 8px; }

.course-page { min-height: calc(100vh - 72px); }
.course-header { position: relative; overflow: hidden; padding: 28px 30px; color: #fff; background: linear-gradient(120deg, var(--course-cover), var(--course-cover2)); }
.course-header::after { content: ""; position: absolute; right: -90px; top: -145px; width: 330px; height: 330px; border: 1px solid rgba(255,255,255,.2); border-radius: 50%; }
.course-header-inner { position: relative; z-index: 1; max-width: 1420px; margin: 0 auto; }
.course-header .back-link { display: inline-flex; align-items: center; gap: 7px; margin-bottom: 18px; color: rgba(255,255,255,.8); background: transparent; border: 0; font-size: 9px; font-weight: 800; }
.course-heading { display: grid; grid-template-columns: 1fr auto; align-items: end; gap: 22px; }
.course-heading .course-kicker { color: rgba(255,255,255,.8); }
.course-heading h1 { max-width: 780px; margin: 8px 0 8px; font-size: clamp(30px,4vw,47px); line-height: 1.05; letter-spacing: -.045em; }
.course-heading p { margin: 0; color: rgba(255,255,255,.78); font-size: 10px; }
.course-progress-box { min-width: 225px; padding: 15px; background: rgba(11,25,48,.24); border: 1px solid rgba(255,255,255,.24); border-radius: 14px; backdrop-filter: blur(10px); }
.course-progress-box > div:first-child { display: flex; justify-content: space-between; gap: 15px; font-size: 9px; }
.course-progress-box strong { font-size: 16px; }
.course-progress-box .progress-line { background: rgba(255,255,255,.19); }
.course-progress-box .progress-line i { background: #fff; }

.course-layout { max-width: 1420px; display: grid; grid-template-columns: 320px minmax(0,1fr); gap: 18px; margin: 0 auto; padding: 20px 28px 62px; align-items: start; }
.curriculum-sidebar { position: sticky; top: 92px; overflow: hidden; max-height: calc(100vh - 112px); background: var(--surface); border: 1px solid var(--line); border-radius: 17px; }
.curriculum-head { display: flex; align-items: center; justify-content: space-between; padding: 17px; border-bottom: 1px solid var(--line); }
.curriculum-head h2 { margin: 0; font-size: 15px; }
.curriculum-head span { color: var(--muted); font-size: 8px; }
.curriculum-scroll { overflow: auto; max-height: calc(100vh - 177px); }
.module-block { border-bottom: 1px solid var(--line); }
.module-block:last-child { border-bottom: 0; }
.module-toggle { width: 100%; display: grid; grid-template-columns: 1fr auto; gap: 9px; padding: 14px 16px; background: var(--surface-2); border: 0; text-align: left; }
.module-toggle b { font-size: 10px; }
.module-toggle small { display: block; margin-top: 3px; color: var(--muted); font-size: 8px; }
.module-toggle span { color: var(--muted); font-size: 12px; transition: transform .2s; }
.module-block.collapsed .module-toggle span { transform: rotate(-90deg); }
.module-block.collapsed .lesson-list { display: none; }
.lesson-list { display: grid; }
.lesson-item { width: 100%; display: grid; grid-template-columns: 25px 1fr auto; align-items: center; gap: 9px; min-height: 54px; padding: 9px 13px; color: var(--muted); background: var(--surface); border: 0; border-top: 1px solid var(--line); text-align: left; }
.lesson-item:hover { background: color-mix(in srgb, var(--surface-2) 60%, transparent); }
.lesson-item.active { color: var(--blue); background: rgba(53,103,233,.07); box-shadow: inset 3px 0 0 var(--blue); }
.lesson-item.completed { color: var(--green); }
.lesson-status { width: 23px; height: 23px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 50%; font-size: 8px; }
.lesson-item.completed .lesson-status { color: #fff; background: var(--green); border-color: var(--green); }
.lesson-item b { display: block; color: var(--ink); font-size: 9px; line-height: 1.3; }
.lesson-item.active b { color: var(--blue); }
.lesson-item small { font-size: 7px; }
.lesson-item > small { color: var(--muted); }

.lesson-area { min-width: 0; }
.lesson-player { position: relative; overflow: hidden; aspect-ratio: 16/9; color: #fff; background: linear-gradient(135deg, var(--course-cover), var(--course-cover2)); border-radius: 19px; box-shadow: 0 18px 45px rgba(18,38,68,.15); }
.lesson-player video { position: absolute; z-index: 0; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: .3; mix-blend-mode: screen; }
.lesson-player::before { content: ""; position: absolute; width: 55%; aspect-ratio: 1; right: -14%; top: -48%; border: 1px solid rgba(255,255,255,.17); border-radius: 50%; }
.lesson-player::after { content: ""; position: absolute; width: 26%; aspect-ratio: 1; left: 11%; bottom: -18%; background: rgba(255,255,255,.08); border-radius: 28%; transform: rotate(24deg); }
.player-center { position: absolute; z-index: 2; inset: 0; display: grid; place-items: center; text-align: center; }
.player-center-content { max-width: 500px; padding: 25px; }
.lesson-symbol { width: 76px; height: 76px; display: grid; place-items: center; margin: 0 auto 16px; background: rgba(255,255,255,.16); border: 1px solid rgba(255,255,255,.32); border-radius: 23px; font-size: 35px; backdrop-filter: blur(10px); }
.player-center h2 { margin: 0 0 7px; font-size: clamp(20px,3vw,34px); line-height: 1.1; }
.player-center p { margin: 0; color: rgba(255,255,255,.72); font-size: 9px; }
.player-center.playing .lesson-symbol { animation: pulse 1.8s infinite; }
@keyframes pulse { 50% { transform: scale(1.06); box-shadow: 0 0 0 16px rgba(255,255,255,.06); } }
.player-controls { position: absolute; z-index: 4; right: 0; bottom: 0; left: 0; padding: 12px 14px; background: linear-gradient(transparent,rgba(5,14,30,.78)); }
.player-timeline { position: relative; height: 5px; margin-bottom: 10px; background: rgba(255,255,255,.25); border-radius: 99px; cursor: pointer; }
.player-timeline i { display: block; width: 0; height: 100%; background: #fff; border-radius: inherit; }
.control-row { display: flex; align-items: center; gap: 9px; }
.control-row button, .control-row select { color: #fff; background: transparent; border: 0; font-size: 10px; }
.control-row .play-control { width: 31px; height: 31px; display: grid; place-items: center; background: #fff; color: #10243f; border-radius: 50%; font-size: 13px; }
.control-row .time-label { color: rgba(255,255,255,.75); font-size: 8px; }
.control-spacer { flex: 1; }
.speed-select option { color: #10243f; }
.lesson-card { margin-top: 16px; padding: 23px 24px; background: var(--surface); border: 1px solid var(--line); border-radius: 17px; }
.lesson-card-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; padding-bottom: 18px; border-bottom: 1px solid var(--line); }
.lesson-card-head > div { min-width: 0; }
.lesson-card-head span { color: var(--blue); font-size: 8px; font-weight: 850; letter-spacing: .1em; text-transform: uppercase; }
.lesson-card-head h2 { margin: 6px 0 6px; font-size: 22px; letter-spacing: -.025em; }
.lesson-card-head p { margin: 0; color: var(--muted); font-size: 9px; }
.lesson-notes { max-width: 850px; padding: 20px 0 3px; color: color-mix(in srgb,var(--ink) 84%,transparent); font-size: 11px; line-height: 1.75; }
.lesson-notes h3 { margin: 1.25em 0 .45em; color: var(--ink); font-size: 15px; }
.lesson-notes ul { padding-left: 19px; }
.lesson-notes li { margin-bottom: 5px; }
.lesson-footer { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 17px; padding-top: 17px; border-top: 1px solid var(--line); }
.lesson-footer > div { display: flex; gap: 8px; }

.modal { position: fixed; z-index: 100; inset: 0; display: grid; place-items: center; padding: 20px; background: rgba(9,23,43,.58); backdrop-filter: blur(8px); }
.modal[hidden] { display: none; }
.modal-card { width: min(540px,100%); max-height: calc(100vh - 40px); overflow: auto; background: var(--surface); border: 1px solid var(--line); border-radius: 19px; box-shadow: 0 28px 80px rgba(5,19,39,.27); }
.modal-card.wide { width: min(720px,100%); }
.modal-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 14px; padding: 20px 21px 16px; border-bottom: 1px solid var(--line); }
.modal-head span { color: var(--blue); font-size: 8px; font-weight: 850; letter-spacing: .12em; text-transform: uppercase; }
.modal-head h2 { margin: 5px 0 0; font-size: 22px; letter-spacing: -.025em; }
.close-button { width: 32px; height: 32px; display: grid; place-items: center; background: var(--surface-2); border: 1px solid var(--line); border-radius: 9px; font-size: 17px; }
.modal-body { padding: 20px 21px; }
.modal-body > p { margin: 0; color: var(--muted); font-size: 10px; line-height: 1.65; }
.modal-actions { display: flex; justify-content: flex-end; gap: 8px; padding: 15px 21px 20px; }
.enroll-summary { display: grid; grid-template-columns: 98px 1fr; gap: 15px; }
.enroll-summary .mini-cover { height: 100px; border-radius: 13px; }
.enroll-summary h3 { margin: 5px 0 7px; font-size: 16px; }
.enroll-summary p { margin: 0; color: var(--muted); font-size: 9px; }
.enroll-points { display: grid; gap: 8px; margin-top: 17px; }
.enroll-points div { display: flex; align-items: center; gap: 9px; color: var(--muted); font-size: 9px; }
.enroll-points span { width: 22px; height: 22px; display: grid; place-items: center; color: var(--green); background: rgba(45,165,121,.1); border-radius: 50%; }
.achievement-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 11px; }
.achievement { padding: 16px 10px; background: var(--bg); border: 1px solid var(--line); border-radius: 13px; text-align: center; }
.achievement > span { width: 45px; height: 45px; display: grid; place-items: center; margin: 0 auto 9px; background: color-mix(in srgb,var(--badge) 15%,transparent); border-radius: 14px; font-size: 21px; }
.achievement b { display: block; font-size: 9px; }
.achievement small { display: block; margin-top: 3px; color: var(--muted); font-size: 7px; }
.achievement.locked { filter: grayscale(1); opacity: .48; }
.settings-list { display: grid; gap: 10px; }
.settings-item { display: grid; grid-template-columns: 38px 1fr auto; align-items: center; gap: 11px; padding: 12px; background: var(--bg); border: 1px solid var(--line); border-radius: 11px; }
.settings-item > span { width: 38px; height: 38px; display: grid; place-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: 10px; }
.settings-item div { display: grid; gap: 2px; }
.settings-item b { font-size: 10px; }
.settings-item small { color: var(--muted); font-size: 8px; }
.settings-item button { padding: 7px 9px; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; font-size: 8px; font-weight: 800; }
.certificate { padding: 38px; background: #fffdf7; border: 10px double #d8b965; text-align: center; color: #17304e; }
.certificate .seal { width: 67px; height: 67px; display: grid; place-items: center; margin: 0 auto 14px; color: #fff; background: #315da7; border-radius: 50%; border: 5px double #fff; font-size: 24px; }
.certificate small { color: #7b725e; font-size: 8px; letter-spacing: .18em; text-transform: uppercase; }
.certificate h2 { margin: 12px 0 5px; font-family: Georgia,serif; font-size: 30px; }
.certificate h3 { margin: 10px 0; color: #315da7; font-family: Georgia,serif; font-size: 19px; }
.certificate p { margin: 0; color: #6f6a5f; font-size: 9px; }

.toast-region { position: fixed; z-index: 200; right: 21px; bottom: 21px; display: grid; gap: 8px; pointer-events: none; }
.toast { min-width: 260px; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 13px 15px; color: #fff; background: var(--navy); border: 1px solid rgba(255,255,255,.12); border-radius: 11px; box-shadow: var(--shadow); font-size: 9px; pointer-events: auto; animation: toast-in .22s ease both; }
.toast button { color: var(--mint); background: transparent; border: 0; font-size: 8px; font-weight: 850; text-transform: uppercase; }
@keyframes toast-in { from { opacity: 0; transform: translateY(12px); } }
.sidebar-scrim { position: fixed; z-index: 29; inset: 0; background: rgba(7,20,39,.45); }
.sidebar-scrim[hidden] { display: none; }
.mobile-nav { display: none; }

body.dark { --bg:#121a26; --surface:#192434; --surface-2:#223043; --ink:#edf3fb; --muted:#9aa9bb; --line:#2d3c50; --navy:#0a1422; --shadow:0 14px 42px rgba(0,0,0,.25); }
body.dark .sidebar { background: #091320; }
body.dark .welcome-hero { box-shadow: none; }
body.dark .course-card, body.dark .learning-card, body.dark .lesson-card, body.dark .curriculum-sidebar { box-shadow: none; }
body.dark .certificate { color: #17304e; }

@media (max-width: 1200px) {
  .course-grid { grid-template-columns: repeat(3,minmax(0,1fr)); }
  .learning-grid { grid-template-columns: 1fr 1fr; }
  .quick-stats { grid-template-columns: 1fr 1fr; }
  .learning-page-grid { grid-template-columns: 1fr; }
  .activity-panel { max-width: none; }
}

@media (max-width: 930px) {
  .sidebar { transform: translateX(-105%); transition: transform .24s ease; box-shadow: 22px 0 55px rgba(6,17,34,.24); }
  body.sidebar-open .sidebar { transform: translateX(0); }
  .main-shell { width: 100%; margin-left: 0; }
  .topbar { grid-template-columns: auto 1fr auto; gap: 11px; padding: 0 15px; }
  .menu-button { display: grid; }
  .page-context { display: none; }
  .global-search { max-width: 520px; justify-self: stretch; }
  .view-page { padding: 27px 17px 88px; }
  .welcome-hero { padding: 30px; }
  .course-layout { grid-template-columns: 280px minmax(0,1fr); padding: 16px 16px 88px; }
  .curriculum-sidebar { top: 88px; }
  .mobile-nav { position: fixed; z-index: 25; right: 0; bottom: 0; left: 0; min-height: 68px; display: grid; grid-template-columns: repeat(5,1fr); padding: 7px 8px max(7px,env(safe-area-inset-bottom)); background: color-mix(in srgb,var(--surface) 94%,transparent); border-top: 1px solid var(--line); backdrop-filter: blur(16px); }
  .mobile-nav a, .mobile-nav button { height: 50px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px; color: var(--muted); background: transparent; border: 0; border-radius: 9px; font-size: 7px; }
  .mobile-nav span { font-size: 17px; }
  .mobile-nav a.active { color: var(--blue); }
  .toast-region { right: 11px; bottom: 80px; left: 11px; }
  .toast { min-width: 0; }
}

@media (max-width: 760px) {
  .topbar { height: 64px; }
  .global-search kbd { display: none; }
  .global-search { grid-template-columns: auto 1fr; }
  .top-actions .notification-button, .top-actions .top-avatar { display: none; }
  #workspace { min-height: calc(100vh - 64px); }
  .page-head { align-items: flex-start; flex-direction: column; }
  .head-actions { justify-content: flex-start; }
  .welcome-hero { grid-template-columns: 1fr; min-height: 310px; padding: 25px 23px; }
  .hero-copy { align-self: start; }
  .hero-visual { position: absolute; right: 2px; bottom: 0; width: 270px; height: 145px; opacity: .78; }
  .quick-stats { gap: 9px; }
  .learning-grid { grid-template-columns: 1fr; }
  .course-grid { grid-template-columns: repeat(2,minmax(0,1fr)); gap: 11px; }
  .course-cover { height: 130px; }
  .filter-bar { align-items: flex-start; flex-direction: column; }
  .filter-group, .filter-search { width: 100%; max-width: none; }
  .filter-select { flex: 1; min-width: 0; }
  .result-count { align-self: flex-end; }
  .learning-list-card { grid-template-columns: 105px 1fr; }
  .learning-list-card .list-progress { grid-column: 1 / -1; min-width: 0; }
  .course-header { padding: 23px 17px; }
  .course-heading { grid-template-columns: 1fr; }
  .course-progress-box { min-width: 0; width: 100%; }
  .course-layout { grid-template-columns: 1fr; padding: 12px 12px 88px; }
  .curriculum-sidebar { position: static; max-height: none; order: 2; }
  .curriculum-scroll { max-height: none; }
  .lesson-area { order: 1; }
  .lesson-player { border-radius: 15px; }
  .lesson-symbol { width: 58px; height: 58px; font-size: 26px; }
  .lesson-card { padding: 19px 17px; }
  .lesson-card-head { align-items: flex-start; flex-direction: column; }
  .lesson-footer { align-items: stretch; flex-direction: column; }
  .lesson-footer > div { justify-content: space-between; }
  .achievement-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 480px) {
  .quick-stats { grid-template-columns: 1fr; }
  .course-grid { grid-template-columns: 1fr; }
  .course-cover { height: 165px; }
  .learning-card { grid-template-columns: 100px 1fr; }
  .filter-group { flex-direction: column; }
  .filter-select { width: 100%; }
  .learning-list-card { grid-template-columns: 1fr; }
  .learning-list-card .mini-cover { height: 130px; }
  .enroll-summary { grid-template-columns: 1fr; }
  .enroll-summary .mini-cover { height: 135px; }
  .settings-item { grid-template-columns: 38px 1fr; }
  .settings-item button { grid-column: 1 / -1; }
  .control-row button:nth-last-of-type(2), .speed-select { display: none; }
  .lesson-card-head .complete-button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *,*::before,*::after { scroll-behavior: auto !important; animation-duration: .001ms !important; transition-duration: .001ms !important; }
}