/* ==========================================================================
   Course Hub — base.css (Foundation)
   Design tokens, reset, app shell layout and every shared component class.
   View CSS (lesson.css, dashboard.css, pages.css) builds on these tokens; do not
   redefine tokens there.

   TOKENS (use var(--name))
     Surfaces: --bg --surface --surface-2 --surface-3 --border --border-strong --scrim
     Text:     --text --text-2 (secondary) --text-3 (faint)
     Accent:   --accent --accent-hover --accent-soft --accent-text --on-accent --focus
     Status:   --success --success-soft --success-text | --warning --warning-soft --warning-text
               --danger --danger-soft --danger-text | --info --info-soft --info-text | --star --star-soft --star-text
     Space:    --space-1 4px  --space-2 8px  --space-3 12px  --space-4 16px  --space-5 24px  --space-6 32px  --space-7 48px
     Radius:   --radius-sm 6px  --radius 10px  --radius-lg 14px  --radius-full
     Shadow:   --shadow-sm --shadow-md --shadow-lg
     Type:     --fs-xs 12px --fs-sm 13px --fs-base 14px --fs-md 16px --fs-lg 20px --fs-xl 24px --fs-2xl 32px
               --font --font-mono --lh-tight 1.25 --lh 1.5 --lh-prose 1.7
     Motion:   --dur 150ms --ease
     Layout:   --sidebar-w 284px --topbar-h 56px --content-w 1180px --prose-w 72ch
   ========================================================================== */

:root {
  color-scheme: light;
  --bg: #f5f6f8;
  --surface: #ffffff;
  --surface-2: #f1f3f6;
  --surface-3: #e7eaef;
  --border: #e2e5eb;
  --border-strong: #cdd2db;
  --scrim: rgba(15, 18, 25, 0.45);

  --text: #1a1e26;
  --text-2: #515968;
  --text-3: #636a78;

  --accent: #6d5dfc;
  --accent-hover: #5a49f2;
  --accent-soft: #efedff;
  --accent-text: #4b3dd4;
  --on-accent: #ffffff;
  --focus: rgba(109, 93, 252, 0.45);

  --success: #16a34a;
  --success-soft: #e5f6eb;
  --success-text: #137a3a;
  --warning: #d98a06;
  --warning-soft: #fdf2df;
  --warning-text: #9a5b04;
  --danger: #dc2626;
  --danger-soft: #fdeceb;
  --danger-text: #b91c1c;
  --info: #0284c7;
  --info-soft: #e3f2fb;
  --info-text: #0369a1;
  --star: #e0a100;
  --star-soft: #fdf5da;
  --star-text: #8a6300;

  --toast-bg: #1d212b;
  --toast-text: #f2f3f7;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;

  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 14px;
  --radius-full: 999px;

  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06);
  --shadow-md: 0 4px 14px rgba(16, 24, 40, 0.08), 0 1px 3px rgba(16, 24, 40, 0.06);
  --shadow-lg: 0 18px 48px rgba(16, 24, 40, 0.18), 0 4px 12px rgba(16, 24, 40, 0.08);

  --font: "Segoe UI Variable Text", "Segoe UI Variable", "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-mono: "Cascadia Mono", Consolas, "SFMono-Regular", Menlo, monospace;
  --fs-xs: 12px;
  --fs-sm: 13px;
  --fs-base: 14px;
  --fs-md: 16px;
  --fs-lg: 20px;
  --fs-xl: 24px;
  --fs-2xl: 32px;
  --lh-tight: 1.25;
  --lh: 1.5;
  --lh-prose: 1.7;

  --dur: 150ms;
  --ease: cubic-bezier(0.2, 0, 0, 1);

  --sidebar-w: 284px;
  --topbar-h: 56px;
  --content-w: 1180px;
  --prose-w: 72ch;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #0e1015;
    --surface: #15181f;
    --surface-2: #1b1f28;
    --surface-3: #252a34;
    --border: #262b35;
    --border-strong: #363c49;
    --scrim: rgba(0, 0, 0, 0.6);
    --text: #e7e9ef;
    --text-2: #a4abb9;
    --text-3: #8a91a0;
    --accent: #8577ff;
    --accent-hover: #978bff;
    --accent-soft: rgba(133, 119, 255, 0.16);
    --accent-text: #b5acff;
    --on-accent: #ffffff;
    --focus: rgba(133, 119, 255, 0.55);
    --success: #22c55e;
    --success-soft: rgba(34, 197, 94, 0.14);
    --success-text: #4ade80;
    --warning: #f5a524;
    --warning-soft: rgba(245, 165, 36, 0.14);
    --warning-text: #fbbf4a;
    --danger: #ef4444;
    --danger-soft: rgba(239, 68, 68, 0.15);
    --danger-text: #f87171;
    --info: #38bdf8;
    --info-soft: rgba(56, 189, 248, 0.14);
    --info-text: #7dd3fc;
    --star: #fbbf24;
    --star-soft: rgba(251, 191, 36, 0.14);
    --star-text: #fcd34d;
    --toast-bg: #2a2f3b;
    --toast-text: #f2f3f7;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.45), 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.6), 0 4px 12px rgba(0, 0, 0, 0.4);
  }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0e1015;
  --surface: #15181f;
  --surface-2: #1b1f28;
  --surface-3: #252a34;
  --border: #262b35;
  --border-strong: #363c49;
  --scrim: rgba(0, 0, 0, 0.6);
  --text: #e7e9ef;
  --text-2: #a4abb9;
  --text-3: #8a91a0;
  --accent: #8577ff;
  --accent-hover: #978bff;
  --accent-soft: rgba(133, 119, 255, 0.16);
  --accent-text: #b5acff;
  --on-accent: #ffffff;
  --focus: rgba(133, 119, 255, 0.55);
  --success: #22c55e;
  --success-soft: rgba(34, 197, 94, 0.14);
  --success-text: #4ade80;
  --warning: #f5a524;
  --warning-soft: rgba(245, 165, 36, 0.14);
  --warning-text: #fbbf4a;
  --danger: #ef4444;
  --danger-soft: rgba(239, 68, 68, 0.15);
  --danger-text: #f87171;
  --info: #38bdf8;
  --info-soft: rgba(56, 189, 248, 0.14);
  --info-text: #7dd3fc;
  --star: #fbbf24;
  --star-soft: rgba(251, 191, 36, 0.14);
  --star-text: #fcd34d;
  --toast-bg: #2a2f3b;
  --toast-text: #f2f3f7;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.45), 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.6), 0 4px 12px rgba(0, 0, 0, 0.4);
}

/* ------------------------------------------------------------------ reset */

*, *::before, *::after { box-sizing: border-box; }
html, body { height: 100%; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: var(--fs-base);
  line-height: var(--lh);
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
h1, h2, h3, h4, h5, h6 { margin: 0; line-height: var(--lh-tight); font-weight: 600; }
p { margin: 0; }
ul, ol { margin: 0; padding: 0; }
img, video, svg, canvas, iframe { display: block; max-width: 100%; }
img, video { height: auto; }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
a { color: inherit; }
table { border-collapse: collapse; }
[hidden] { display: none !important; }
mark { background: var(--star-soft); color: inherit; border-radius: 3px; padding: 0 2px; box-shadow: inset 0 -2px 0 color-mix(in srgb, var(--star) 55%, transparent); }
::selection { background: color-mix(in srgb, var(--accent) 28%, transparent); }

:focus { outline: none; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

* { scrollbar-width: thin; scrollbar-color: var(--border-strong) transparent; }
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 10px; border: 2px solid transparent; background-clip: padding-box; }
::-webkit-scrollbar-thumb:hover { background-color: var(--text-3); }

.icon { flex: none; display: inline-block; vertical-align: middle; }

/* ------------------------------------------------------------------ shell */

.app {
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr);
  flex: 1;
  min-height: 0;
  transition: grid-template-columns var(--dur) var(--ease);
}
html.sidebar-collapsed .app { grid-template-columns: 0 minmax(0, 1fr); }
html.sidebar-collapsed .sidebar { visibility: hidden; }

.sidebar {
  display: flex;
  flex-direction: column;
  min-height: 0;
  min-width: 0;
  overflow: hidden;
  background: var(--surface);
  border-right: 1px solid var(--border);
}
.sidebar-top { flex: none; padding: var(--space-3) var(--space-3) var(--space-2); display: flex; flex-direction: column; gap: var(--space-2); }
.sidebar-brand { display: flex; align-items: center; gap: var(--space-2); min-height: 36px; padding-left: var(--space-1); }
.sidebar-brand-link { display: flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 650; font-size: 15px; flex: 1; min-width: 0; }
.brand-mark { width: 28px; height: 28px; border-radius: 8px; display: grid; place-items: center; background: var(--accent); color: var(--on-accent); flex: none; }
.sidebar-search {
  display: flex; align-items: center; gap: var(--space-2);
  width: 100%; height: 36px; padding: 0 var(--space-2) 0 var(--space-3);
  border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface-2);
  color: var(--text-3); text-align: left; transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.sidebar-search:hover { border-color: var(--border-strong); color: var(--text-2); }
.sidebar-search-label { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
[data-icon] { display: inline-flex; align-items: center; justify-content: center; }
.sidebar-scroll { position: relative; flex: 1; min-height: 0; overflow-y: auto; overscroll-behavior: contain; padding: var(--space-1) var(--space-3) var(--space-6); }

/* --- sidebar footer: who is signed in, with Admin / Change password / Sign out --- */
.sidebar-foot { position: relative; flex: none; padding: var(--space-2) var(--space-3) var(--space-3); border-top: 1px solid var(--border); background: var(--surface); }
.user-button {
  display: flex; align-items: center; gap: var(--space-2); width: 100%;
  padding: 6px var(--space-2); border: 1px solid transparent; border-radius: var(--radius);
  background: transparent; color: var(--text); text-align: left;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.user-button:hover, .user-button[aria-expanded="true"] { background: var(--surface-2); border-color: var(--border); }
.user-avatar {
  flex: none; width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center;
  background: var(--accent-soft); color: var(--accent-text); font-size: var(--fs-xs); font-weight: 650; letter-spacing: 0.02em;
}
.user-id { display: flex; flex-direction: column; min-width: 0; flex: 1; }
.user-name { font-weight: 600; font-size: var(--fs-sm); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.user-sub { font-size: var(--fs-xs); color: var(--text-3); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.user-caret { color: var(--text-3); transition: transform var(--dur) var(--ease); }
.user-button[aria-expanded="true"] .user-caret { transform: rotate(180deg); }

.user-menu {
  position: absolute; left: var(--space-3); right: var(--space-3); bottom: calc(100% - var(--space-2));
  z-index: 30; display: flex; flex-direction: column; gap: 1px; padding: var(--space-1);
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow-lg);
  animation: hub-pop var(--dur) var(--ease);
}
.user-menu-item {
  display: flex; align-items: center; gap: 10px; width: 100%;
  min-height: 34px; padding: 0 var(--space-2); border: 0; border-radius: var(--radius-sm);
  background: transparent; color: var(--text-2); font-weight: 500; text-align: left; text-decoration: none;
}
.user-menu-item:hover { background: var(--surface-2); color: var(--text); }
.user-menu-item .icon { color: var(--text-3); }

.sidebar-nav { display: flex; flex-direction: column; gap: 1px; padding-bottom: var(--space-3); border-bottom: 1px solid var(--border); margin-bottom: var(--space-3); }
.nav-link {
  display: flex; align-items: center; gap: 10px;
  min-height: 34px; padding: 0 var(--space-2); border-radius: var(--radius-sm);
  color: var(--text-2); text-decoration: none; font-weight: 500;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}
.nav-link:hover { background: var(--surface-2); color: var(--text); }
.nav-link.is-active { background: var(--accent-soft); color: var(--accent-text); }
.nav-link .nav-count { margin-left: auto; font-size: var(--fs-xs); color: var(--text-3); font-variant-numeric: tabular-nums; }

.sidebar-program { margin-bottom: var(--space-4); }
.sidebar-program-title {
  display: flex; align-items: center; gap: var(--space-2);
  padding: var(--space-2) var(--space-2) 6px; text-decoration: none;
  font-size: 11.5px; font-weight: 650; letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3);
  border-radius: var(--radius-sm);
}
.sidebar-program-title:hover { color: var(--text); }
.sidebar-program-title.is-active { color: var(--accent-text); }
.sidebar-program-title .program-pct { margin-left: auto; letter-spacing: 0; font-variant-numeric: tabular-nums; font-weight: 600; }

.module-list { display: flex; flex-direction: column; gap: 1px; }
.module-link {
  display: grid;
  grid-template-columns: 22px minmax(0, 1fr) auto;
  grid-template-areas: "icon title count" ". bar bar";
  align-items: center;
  column-gap: var(--space-2);
  row-gap: 5px;
  padding: 7px var(--space-2) 8px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text);
  transition: background var(--dur) var(--ease);
}
.module-link:hover { background: var(--surface-2); }
.module-link.is-active { background: var(--accent-soft); }
.module-link.is-active .module-title { color: var(--accent-text); font-weight: 600; }
.module-icon { grid-area: icon; width: 22px; height: 22px; display: grid; place-items: center; font-size: 15px; line-height: 1; color: var(--text-3); }
.module-title { grid-area: title; display: flex; align-items: center; min-width: 0; font-size: var(--fs-sm); line-height: 1.3; white-space: nowrap; }
.module-title-text { min-width: 0; overflow: hidden; text-overflow: ellipsis; }
.module-count { grid-area: count; font-size: 11.5px; color: var(--text-3); font-variant-numeric: tabular-nums; }
.module-link .progress { grid-area: bar; }
.module-link.is-complete .module-count { color: var(--success-text); }
.module-link .tag { margin-left: 6px; flex-shrink: 0; }

.sidebar-more { margin-top: var(--space-1); }
.sidebar-more > summary {
  list-style: none; display: flex; align-items: center; gap: var(--space-2);
  min-height: 32px; padding: 0 var(--space-2); border-radius: var(--radius-sm);
  font-size: var(--fs-sm); color: var(--text-2); cursor: pointer; user-select: none;
}
.sidebar-more > summary::-webkit-details-marker { display: none; }
.sidebar-more > summary:hover { background: var(--surface-2); color: var(--text); }
.sidebar-more > summary .icon { transition: transform var(--dur) var(--ease); color: var(--text-3); }
.sidebar-more[open] > summary .icon-chevron { transform: rotate(90deg); }
.sidebar-more > summary .more-count { margin-left: auto; font-size: 11.5px; color: var(--text-3); }
.sidebar-more-label { font-size: 10.5px; font-weight: 650; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-3); padding: var(--space-2) var(--space-2) 2px 38px; }

.sidebar-scrim { display: none; }

.shell-main { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.topbar {
  flex: none; height: var(--topbar-h);
  display: flex; align-items: center; gap: var(--space-3);
  padding: 0 var(--space-5) 0 var(--space-3);
  background: var(--surface); border-bottom: 1px solid var(--border);
  position: relative; z-index: 20;
}
.crumbs { display: flex; align-items: center; gap: 6px; min-width: 0; flex: 1; overflow: hidden; white-space: nowrap; }
.crumb { color: var(--text-2); text-decoration: none; overflow: hidden; text-overflow: ellipsis; max-width: 32ch; flex: 0 1 auto; min-width: 0; }
a.crumb:hover { color: var(--text); text-decoration: underline; text-underline-offset: 3px; }
.crumb.is-current { color: var(--text); font-weight: 600; }
.crumb-sep { color: var(--text-3); flex: none; }
.topbar-actions { display: flex; align-items: center; gap: var(--space-2); flex: none; margin-left: auto; }
.topbar-search { display: none; }

.main { flex: 1; min-height: 0; overflow-y: auto; overflow-x: hidden; overscroll-behavior: contain; position: relative; }
.main:focus-visible { outline: none; }
[data-route-focus]:focus, [data-route-focus]:focus-visible { outline: none; } /* heading focused by the router after navigation */
.view { min-height: 100%; }

.banner {
  display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: var(--space-3);
  padding: 10px var(--space-4); background: var(--danger-soft); color: var(--danger-text);
  font-weight: 600; font-size: var(--fs-sm); border-bottom: 1px solid color-mix(in srgb, var(--danger) 30%, transparent);
  flex: none; position: relative; z-index: 130;
}
.banner-pending { font-weight: 500; }

.boot { min-height: 60vh; display: grid; place-items: center; align-content: center; gap: var(--space-3); color: var(--text-2); text-align: center; padding: var(--space-5); }

@media (max-width: 899px) {
  .app, html.sidebar-collapsed .app { grid-template-columns: minmax(0, 1fr); }
  .sidebar {
    position: fixed; top: 0; bottom: 0; left: 0; z-index: 90;
    width: min(88vw, 320px);
    transform: translateX(-102%);
    box-shadow: var(--shadow-lg);
  }
  /* Closed drawer: visibility hidden (after the slide-out) takes its links out of the Tab order.
     The collapsed selector matches the desktop rule's specificity so a desktop-collapsed state can't override it. */
  .sidebar, html.sidebar-collapsed .sidebar {
    visibility: hidden;
    transition: transform 200ms var(--ease), visibility 0s linear 200ms;
  }
  html.sidebar-open .sidebar, html.sidebar-open.sidebar-collapsed .sidebar {
    transform: none;
    visibility: visible;
    transition-delay: 0s;
  }
  html.sidebar-open .sidebar-scrim { display: block; position: fixed; inset: 0; background: var(--scrim); z-index: 80; }
  .topbar { padding: 0 var(--space-3); gap: var(--space-2); }
  .topbar-search { display: inline-flex; }
}
@media (max-width: 599px) {
  .crumb:not(.is-current), .crumb-sep { display: none; }
  .crumb.is-current { max-width: none; }
  .hide-sm { display: none !important; }
}

/* ------------------------------------------------------------------ page scaffolding */

.page { max-width: var(--content-w); margin: 0 auto; padding: var(--space-5) var(--space-6) var(--space-7); }
.page-narrow { max-width: 840px; }
.page-wide { max-width: 1440px; }
.page-header { display: flex; flex-wrap: wrap; align-items: flex-end; justify-content: space-between; gap: var(--space-4); margin-bottom: var(--space-5); }
.page-title { font-size: var(--fs-xl); font-weight: 650; letter-spacing: -0.01em; }
.page-subtitle { color: var(--text-2); margin-top: var(--space-1); }
.section { margin-top: var(--space-6); }
.section-header { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); margin-bottom: var(--space-3); }
.section-title { font-size: var(--fs-md); font-weight: 650; }
.eyebrow { font-size: 11.5px; font-weight: 650; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-3); }
@media (max-width: 599px) {
  .page { padding: var(--space-4) var(--space-4) var(--space-7); }
  .page-title { font-size: var(--fs-lg); }
}

/* ------------------------------------------------------------------ utilities */

.muted { color: var(--text-2); }
.faint { color: var(--text-3); }
.small { font-size: var(--fs-sm); }
.xs { font-size: var(--fs-xs); }
.strong { font-weight: 600; }
.nums { font-variant-numeric: tabular-nums; }
.truncate { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; min-width: 0; }
.line-clamp-2 { display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.line-clamp-3 { display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.sr-only { position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.link { color: var(--accent-text); text-decoration: none; }
.link:hover { text-decoration: underline; text-underline-offset: 3px; }
.divider { border: 0; border-top: 1px solid var(--border); margin: var(--space-4) 0; }
.flex-1 { flex: 1; min-width: 0; }
.ml-auto { margin-left: auto; }

.stack { display: flex; flex-direction: column; gap: var(--space-3); }
.stack-xs { gap: var(--space-1); }
.stack-sm { gap: var(--space-2); }
.stack-lg { gap: var(--space-5); }
.row { display: flex; align-items: center; gap: var(--space-2); min-width: 0; }
.row-wrap { flex-wrap: wrap; }
.row-between { justify-content: space-between; }
.row-end { justify-content: flex-end; }
.row-top { align-items: flex-start; }
.row-lg { gap: var(--space-4); }

.grid { display: grid; gap: var(--space-4); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-auto { grid-template-columns: repeat(auto-fill, minmax(min(var(--min, 260px), 100%), 1fr)); }
@media (max-width: 1099px) { .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); } .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 599px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: minmax(0, 1fr); } }

/* ------------------------------------------------------------------ buttons */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  height: 36px; padding: 0 14px; border-radius: var(--radius);
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  font-size: var(--fs-base); font-weight: 550; line-height: 1; white-space: nowrap; text-decoration: none;
  user-select: none; -webkit-user-select: none;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease), color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.btn:hover { background: var(--surface-2); border-color: var(--border-strong); }
.btn:active { transform: translateY(0.5px); }
.btn[disabled], .btn[aria-disabled="true"] { opacity: 0.5; pointer-events: none; }
.btn.is-active, .btn[aria-pressed="true"] { background: var(--accent-soft); border-color: color-mix(in srgb, var(--accent) 40%, transparent); color: var(--accent-text); }

.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--on-accent); }
.btn-primary.is-active, .btn-primary[aria-pressed="true"] { background: var(--accent-hover); color: var(--on-accent); }
.btn-success { background: var(--success); border-color: var(--success); color: #fff; }
.btn-success:hover { background: color-mix(in srgb, var(--success) 88%, #000); border-color: transparent; color: #fff; }
.btn-danger { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn-danger:hover { background: color-mix(in srgb, var(--danger) 88%, #000); border-color: transparent; color: #fff; }
.btn-ghost { background: transparent; border-color: transparent; color: var(--text-2); }
.btn-ghost:hover { background: var(--surface-2); border-color: transparent; color: var(--text); }
.btn-soft { background: var(--accent-soft); border-color: transparent; color: var(--accent-text); }
.btn-soft:hover { background: color-mix(in srgb, var(--accent) 22%, transparent); border-color: transparent; }
.btn-sm { height: 30px; padding: 0 10px; font-size: var(--fs-sm); border-radius: var(--radius-sm); gap: 6px; }
.btn-lg { height: 44px; padding: 0 20px; font-size: var(--fs-md); border-radius: var(--radius); }
.btn-block { width: 100%; }

.btn-icon {
  display: inline-flex; align-items: center; justify-content: center; flex: none;
  width: 36px; height: 36px; padding: 0; border-radius: var(--radius);
  border: 1px solid transparent; background: transparent; color: var(--text-2);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}
.btn-icon:hover { background: var(--surface-2); color: var(--text); }
.btn-icon[disabled] { opacity: 0.45; pointer-events: none; }
.btn-icon.is-active, .btn-icon[aria-pressed="true"] { color: var(--accent-text); background: var(--accent-soft); }
.btn.btn-icon { width: 36px; padding: 0; border-color: var(--border); background: var(--surface); }
.btn.btn-icon:hover { background: var(--surface-2); }
.btn-icon.btn-sm, .btn.btn-icon.btn-sm { width: 30px; height: 30px; border-radius: var(--radius-sm); }
.btn-icon.btn-lg { width: 44px; height: 44px; }

/* ------------------------------------------------------------------ cards, chips, badges, tags */

.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: var(--space-4); box-shadow: var(--shadow-sm); min-width: 0;
}
.card-lg { padding: var(--space-5); }
.card-flush { padding: 0; overflow: hidden; }
.card-header { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); margin-bottom: var(--space-3); }
.card-title { font-size: var(--fs-md); font-weight: 650; }
.card-link { display: block; text-decoration: none; color: inherit; transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease), transform var(--dur) var(--ease); }
.card-link:hover, .card-hover:hover { border-color: var(--border-strong); box-shadow: var(--shadow-md); }

.chip {
  display: inline-flex; align-items: center; gap: 6px;
  height: 30px; padding: 0 12px; border-radius: var(--radius-full);
  border: 1px solid var(--border); background: var(--surface); color: var(--text-2);
  font-size: var(--fs-sm); font-weight: 500; white-space: nowrap; text-decoration: none;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
button.chip, a.chip { cursor: pointer; }
.chip:hover { border-color: var(--border-strong); color: var(--text); }
.chip.is-active, .chip[aria-pressed="true"] { background: var(--accent-soft); border-color: color-mix(in srgb, var(--accent) 45%, transparent); color: var(--accent-text); }
.chip .chip-count { font-size: 11.5px; color: inherit; opacity: 0.75; font-variant-numeric: tabular-nums; }
.chips { display: flex; flex-wrap: wrap; gap: var(--space-2); }

.badge {
  display: inline-flex; align-items: center; gap: 4px;
  height: 20px; padding: 0 7px; border-radius: var(--radius-full);
  background: var(--surface-2); color: var(--text-2);
  font-size: 11px; font-weight: 650; letter-spacing: 0.02em; line-height: 1; white-space: nowrap; flex: none;
}
.badge-star { background: var(--star-soft); color: var(--star-text); }
.badge-star .icon { color: var(--star); }
.badge-new { background: var(--accent-soft); color: var(--accent-text); }
.badge-action { background: var(--info-soft); color: var(--info-text); }
.badge-success { background: var(--success-soft); color: var(--success-text); }
.badge-warning { background: var(--warning-soft); color: var(--warning-text); }
.badge-danger { background: var(--danger-soft); color: var(--danger-text); }
.badge-dup { background: var(--surface-3); color: var(--text-2); }

.tag {
  display: inline-flex; align-items: center; height: 17px; padding: 0 5px; border-radius: 4px;
  border: 1px solid var(--border-strong); color: var(--text-3);
  font-size: 10px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.04em; line-height: 1;
}

.kbd {
  display: inline-flex; align-items: center; justify-content: center; min-width: 20px; height: 20px; padding: 0 5px;
  border: 1px solid var(--border-strong); border-bottom-width: 2px; border-radius: 5px;
  background: var(--surface); color: var(--text-2);
  font-family: var(--font-mono); font-size: 11px; line-height: 1; white-space: nowrap;
}

/* ------------------------------------------------------------------ progress, ring, status dot */

.progress { position: relative; width: 100%; height: 6px; border-radius: var(--radius-full); background: var(--surface-3); overflow: hidden; }
.progress-xs { height: 3px; }
.progress-sm { height: 6px; }
.progress-md { height: 8px; }
.progress-fill { height: 100%; width: 0; border-radius: inherit; background: var(--accent); transition: width 300ms var(--ease); }
.progress.tone-success .progress-fill { background: var(--success); }
.progress.tone-warning .progress-fill { background: var(--warning); }

.ring { position: relative; display: inline-grid; place-items: center; flex: none; }
.ring svg { position: absolute; inset: 0; }
.ring-track { stroke: var(--surface-3); }
.ring-value { stroke: var(--accent); transition: stroke-dashoffset 500ms var(--ease); }
.ring.tone-success .ring-value { stroke: var(--success); }
.ring.tone-warning .ring-value { stroke: var(--warning); }
.ring-label { position: relative; font-size: var(--ring-font, 14px); font-weight: 650; font-variant-numeric: tabular-nums; }

.status-dot {
  position: relative; flex: none; display: inline-grid; place-items: center;
  width: 22px; height: 22px; padding: 0; margin: 0;
  border-radius: 50%; border: 2px solid var(--border-strong); background: transparent; color: #fff;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  z-index: 1;
}
.status-dot-sm { width: 18px; height: 18px; }
.status-dot .icon { width: 12px; height: 12px; opacity: 0; stroke-width: 3; transition: opacity var(--dur) var(--ease); }
.status-dot-sm .icon { width: 10px; height: 10px; }
button.status-dot::before { content: ""; position: absolute; inset: -9px; border-radius: 50%; }
button.status-dot:hover { border-color: var(--success); }
button.status-dot:hover .icon { opacity: 0.55; color: var(--success); }
.status-dot[data-status="in_progress"] {
  border-color: var(--warning);
  background: conic-gradient(var(--warning) 0 50%, transparent 50% 100%);
  box-shadow: inset 0 0 0 2px var(--surface);
}
.status-dot[data-status="done"] { border-color: var(--success); background: var(--success); box-shadow: none; }
.status-dot[data-status="done"] .icon { opacity: 1; color: #fff; }
button.status-dot[data-status="done"]:hover { background: color-mix(in srgb, var(--success) 80%, #000); }
button.status-dot[data-status="done"]:hover .icon { color: #fff; opacity: 1; }
button.status-dot:focus-visible { outline-offset: 3px; border-radius: 50%; }

/* ------------------------------------------------------------------ lesson row */

.lesson-list { display: flex; flex-direction: column; gap: 1px; }
.lesson-row {
  position: relative; display: flex; align-items: center; gap: var(--space-3);
  min-height: 48px; padding: 8px var(--space-3); border-radius: var(--radius);
  transition: background var(--dur) var(--ease);
}
.lesson-row:hover { background: var(--surface-2); }
.lesson-row.is-active { background: var(--accent-soft); }
.lesson-row.is-active .lesson-row-title { color: var(--accent-text); font-weight: 600; }
.lesson-row.is-compact { min-height: 38px; padding: 6px var(--space-2); gap: var(--space-2); }
.lesson-row:has(.lesson-row-title:focus-visible) { box-shadow: 0 0 0 2px var(--accent); }
.lesson-row-num { flex: none; min-width: 2.2em; text-align: right; font-size: var(--fs-xs); color: var(--text-3); font-variant-numeric: tabular-nums; }
.lesson-row-main { flex: 1; min-width: 0; display: flex; flex-direction: column; gap: 2px; }
.lesson-row-line { display: flex; align-items: center; flex-wrap: wrap; column-gap: 6px; row-gap: 2px; min-width: 0; }
.lesson-row-title { color: var(--text); text-decoration: none; font-weight: 500; line-height: 1.35; overflow-wrap: anywhere; }
.lesson-row-title:focus-visible { outline: none; }
.lesson-row-title::after { content: ""; position: absolute; inset: 0; border-radius: inherit; }
.lesson-row.is-compact .lesson-row-title { font-size: var(--fs-sm); }
.lesson-row[data-status="done"] .lesson-row-title { color: var(--text-2); }
.lesson-row-sub { font-size: var(--fs-xs); color: var(--text-3); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.lesson-row-bar { max-width: 220px; margin-top: 4px; }
.lesson-row-meta { flex: none; display: flex; align-items: center; gap: 10px; color: var(--text-3); font-size: var(--fs-xs); font-variant-numeric: tabular-nums; }
.lesson-row-meta > span { display: inline-flex; align-items: center; gap: 3px; }
.lesson-row-note { color: var(--accent-text); }
.lesson-row-dur { min-width: 4.4em; justify-content: flex-end; }
.lesson-row .status-dot, .lesson-row .lesson-row-meta button, .lesson-row a:not(.lesson-row-title), .lesson-row button:not(.status-dot) { position: relative; z-index: 1; }
@media (max-width: 599px) {
  .lesson-row { gap: var(--space-2); padding: 8px; }
  .lesson-row-num, .lesson-row-kind, .lesson-row-attach { display: none !important; }
  .lesson-row-dur { min-width: 0; }
}

/* ------------------------------------------------------------------ tabs, segmented */

.tabs { display: flex; align-items: flex-end; gap: var(--space-1); border-bottom: 1px solid var(--border); overflow-x: auto; scrollbar-width: none; }
.tabs::-webkit-scrollbar { display: none; }
.tab {
  position: relative; display: inline-flex; align-items: center; gap: 6px;
  height: 42px; padding: 0 var(--space-3); margin-bottom: -1px;
  border: 0; border-bottom: 2px solid transparent; background: transparent;
  color: var(--text-2); font-weight: 550; white-space: nowrap; text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.tab:hover { color: var(--text); }
.tab.is-active, .tab[aria-selected="true"] { color: var(--text); border-bottom-color: var(--accent); }
.tab-count { font-size: 11px; font-weight: 650; min-width: 18px; height: 18px; padding: 0 5px; border-radius: var(--radius-full); background: var(--surface-3); color: var(--text-2); display: inline-grid; place-items: center; }
.tab.is-active .tab-count, .tab[aria-selected="true"] .tab-count { background: var(--accent-soft); color: var(--accent-text); }

.seg { display: inline-flex; padding: 3px; gap: 2px; border-radius: var(--radius); background: var(--surface-2); border: 1px solid var(--border); flex-wrap: wrap; }
.seg > button { height: 28px; padding: 0 12px; border: 0; border-radius: 7px; background: transparent; color: var(--text-2); font-size: var(--fs-sm); font-weight: 550; display: inline-flex; align-items: center; gap: 6px; }
.seg > button:hover { color: var(--text); }
.seg > button.is-active, .seg > button[aria-pressed="true"] { background: var(--surface); color: var(--text); box-shadow: var(--shadow-sm); }

/* ------------------------------------------------------------------ forms */

.field { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.label { font-size: var(--fs-sm); font-weight: 550; color: var(--text-2); }
.hint { font-size: var(--fs-xs); color: var(--text-3); }
.form-error {
  padding: var(--space-2) var(--space-3); border-radius: var(--radius-sm);
  background: var(--danger-soft); border: 1px solid color-mix(in srgb, var(--danger) 30%, transparent);
  color: var(--danger-text); font-size: var(--fs-sm);
}
.input, .select, .textarea {
  width: 100%; min-width: 0; height: 36px; padding: 0 var(--space-3);
  border: 1px solid var(--border-strong); border-radius: var(--radius); background: var(--surface); color: var(--text);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.input::placeholder, .textarea::placeholder { color: var(--text-3); }
.input:hover, .select:hover, .textarea:hover { border-color: var(--text-3); }
.input:focus, .select:focus, .textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--focus); }
.input-sm { height: 30px; font-size: var(--fs-sm); border-radius: var(--radius-sm); }
.select { appearance: none; -webkit-appearance: none; padding-right: 32px; background-image: linear-gradient(45deg, transparent 50%, var(--text-3) 50%), linear-gradient(135deg, var(--text-3) 50%, transparent 50%); background-position: calc(100% - 17px) 15px, calc(100% - 12px) 15px; background-size: 5px 5px; background-repeat: no-repeat; }
.textarea { height: auto; min-height: 140px; padding: 10px var(--space-3); line-height: var(--lh-prose); resize: vertical; }
.input-icon { position: relative; display: flex; align-items: center; min-width: 0; }
.input-icon > .icon { position: absolute; left: 11px; color: var(--text-3); pointer-events: none; }
.input-icon > .input { padding-left: 34px; }
input[type="checkbox"], input[type="radio"] { accent-color: var(--accent); width: 16px; height: 16px; margin: 0; }
.check { display: inline-flex; align-items: center; gap: var(--space-2); cursor: pointer; min-height: 32px; }

.switch {
  appearance: none; -webkit-appearance: none; position: relative; flex: none;
  width: 36px !important; height: 20px !important; border-radius: var(--radius-full);
  background: var(--border-strong); cursor: pointer; transition: background var(--dur) var(--ease);
}
.switch::after {
  content: ""; position: absolute; top: 2px; left: 2px; width: 16px; height: 16px; border-radius: 50%;
  background: #fff; box-shadow: 0 1px 2px rgba(0, 0, 0, 0.25); transition: transform var(--dur) var(--ease);
}
.switch:checked { background: var(--accent); }
.switch:checked::after { transform: translateX(16px); }
.switch:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ------------------------------------------------------------------ empty, spinner, skeleton */

.empty { display: flex; flex-direction: column; align-items: center; text-align: center; gap: var(--space-2); padding: var(--space-7) var(--space-4); color: var(--text-2); }
.empty-icon { width: 56px; height: 56px; border-radius: 50%; background: var(--surface-2); color: var(--text-3); display: grid; place-items: center; margin-bottom: var(--space-2); }
.empty-title { font-size: var(--fs-md); font-weight: 650; color: var(--text); }
.empty-text { max-width: 46ch; }
.empty-action { margin-top: var(--space-3); display: flex; gap: var(--space-2); flex-wrap: wrap; justify-content: center; }

.spinner { display: inline-block; flex: none; border-radius: 50%; border: 2px solid var(--surface-3); border-top-color: var(--accent); animation: hub-spin 700ms linear infinite; }
@keyframes hub-spin { to { transform: rotate(360deg); } }
.skeleton { border-radius: var(--radius-sm); background: linear-gradient(90deg, var(--surface-2) 25%, var(--surface-3) 50%, var(--surface-2) 75%); background-size: 200% 100%; animation: hub-shimmer 1.3s ease-in-out infinite; min-height: 12px; }
@keyframes hub-shimmer { to { background-position: -200% 0; } }

.stat { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.stat-value { font-size: var(--fs-xl); font-weight: 650; font-variant-numeric: tabular-nums; letter-spacing: -0.01em; line-height: 1.15; }
.stat-label { font-size: var(--fs-xs); color: var(--text-3); font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; }

.thumb { position: relative; aspect-ratio: 16 / 9; border-radius: var(--radius); background: var(--surface-3); overflow: hidden; }
.thumb > img { width: 100%; height: 100%; object-fit: cover; }

.callout { display: flex; gap: var(--space-3); padding: var(--space-3) var(--space-4); border-radius: var(--radius); background: var(--surface-2); border: 1px solid var(--border); }
.callout-info { background: var(--info-soft); border-color: color-mix(in srgb, var(--info) 30%, transparent); color: var(--info-text); }
.callout-action { background: var(--info-soft); border-color: color-mix(in srgb, var(--info) 30%, transparent); }
.callout-success { background: var(--success-soft); border-color: color-mix(in srgb, var(--success) 30%, transparent); }
.callout-warning { background: var(--warning-soft); border-color: color-mix(in srgb, var(--warning) 30%, transparent); }

/* ------------------------------------------------------------------ prose (lesson notes, previews) */

.prose { max-width: var(--prose-w); font-size: 15.5px; line-height: var(--lh-prose); color: var(--text); overflow-wrap: break-word; }
.prose > * + * { margin-top: 0.9em; }
.prose h1, .prose h2, .prose h3, .prose h4 { margin-top: 1.6em; margin-bottom: 0.2em; letter-spacing: -0.005em; }
.prose h1 { font-size: 1.6em; }
.prose h2 { font-size: 1.35em; }
.prose h3 { font-size: 1.15em; }
.prose h4 { font-size: 1em; }
.prose > :first-child { margin-top: 0; }
.prose p { margin: 0; }
.prose a { color: var(--accent-text); text-decoration: underline; text-decoration-color: color-mix(in srgb, var(--accent) 40%, transparent); text-underline-offset: 3px; }
.prose a:hover { text-decoration-color: currentColor; }
.prose ul, .prose ol { padding-left: 1.4em; }
.prose li + li { margin-top: 0.3em; }
.prose li > ul, .prose li > ol { margin-top: 0.3em; }
.prose blockquote { margin: 0; padding: 0.2em 0 0.2em 1em; border-left: 3px solid var(--border-strong); color: var(--text-2); }
.prose code { font-family: var(--font-mono); font-size: 0.88em; padding: 0.1em 0.35em; border-radius: 4px; background: var(--surface-2); }
.prose pre { padding: var(--space-3) var(--space-4); border-radius: var(--radius); background: var(--surface-2); overflow-x: auto; font-size: 13px; line-height: 1.55; }
.prose pre code { padding: 0; background: none; }
.prose img { border-radius: var(--radius); border: 1px solid var(--border); }
.prose hr { border: 0; border-top: 1px solid var(--border); margin: 1.6em 0; }
.prose table { width: 100%; font-size: 14px; }
.prose th, .prose td { border: 1px solid var(--border); padding: 6px 10px; text-align: left; vertical-align: top; }
.prose th { background: var(--surface-2); font-weight: 600; }
.prose strong { font-weight: 650; }
.table-wrap { overflow-x: auto; max-width: 100%; }

/* ------------------------------------------------------------------ modal */

/* minmax(0, 1fr) stops wide content (tables, slides) from growing the grid column past the viewport. */
.modal-root { position: fixed; inset: 0; z-index: 100; display: grid; grid-template-columns: minmax(0, 1fr); place-items: center; padding: var(--space-4); animation: hub-fade 140ms var(--ease); }
.modal-root.is-leaving { animation: hub-fade-out 140ms var(--ease) forwards; }
.modal-backdrop { position: absolute; inset: 0; background: var(--scrim); }
.modal {
  position: relative; display: flex; flex-direction: column;
  width: 100%; min-width: 0; max-width: 560px; max-height: calc(100dvh - 32px);
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
  animation: hub-pop 160ms var(--ease);
}
.modal:focus-visible { outline: none; }
.modal-sm { max-width: 420px; }
.modal-md { max-width: 560px; }
.modal-lg { max-width: 840px; }
.modal-xl { max-width: 1140px; height: calc(100dvh - 64px); }
.modal-full { max-width: none; width: calc(100vw - 32px); height: calc(100dvh - 32px); }
.modal-header { display: flex; align-items: center; gap: var(--space-3); padding: 12px 12px 12px var(--space-5); border-bottom: 1px solid var(--border); flex: none; min-height: 56px; }
.modal-title { flex: 1; min-width: 0; font-size: var(--fs-md); font-weight: 650; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.modal-header-actions { display: flex; align-items: center; gap: var(--space-2); flex-wrap: wrap; }
.modal-body { flex: 1; min-height: 0; overflow: auto; padding: var(--space-5); }
.modal-footer { display: flex; justify-content: flex-end; flex-wrap: wrap; gap: var(--space-2); padding: 12px var(--space-5); border-top: 1px solid var(--border); flex: none; }
.confirm-text { color: var(--text-2); white-space: pre-line; }
body.has-modal .main { overflow: hidden; }
@keyframes hub-fade { from { opacity: 0; } }
@keyframes hub-fade-out { to { opacity: 0; } }
@keyframes hub-pop { from { opacity: 0; transform: translateY(6px) scale(0.985); } }
@media (max-width: 599px) {
  .modal-root { padding: var(--space-2); }
  .modal, .modal-full, .modal-xl { max-height: calc(100dvh - 16px); }
  .modal-full, .modal-xl { width: 100%; height: calc(100dvh - 16px); }
  .modal-header { padding-left: var(--space-4); }
  .modal-body { padding: var(--space-4); }
  .modal-header-actions .btn-label { display: none; }
}

/* ------------------------------------------------------------------ toast */

.toast-stack { position: fixed; left: 50%; bottom: 20px; transform: translateX(-50%); z-index: 140; display: flex; flex-direction: column; align-items: center; gap: var(--space-2); width: max-content; max-width: calc(100vw - 24px); pointer-events: none; }
.toast {
  pointer-events: auto; display: flex; align-items: center; gap: var(--space-2);
  min-height: 42px; max-width: 100%; padding: 6px 6px 6px var(--space-4);
  border-radius: var(--radius); background: var(--toast-bg); color: var(--toast-text);
  box-shadow: var(--shadow-lg); font-size: var(--fs-sm); font-weight: 500;
  animation: hub-toast-in 180ms var(--ease);
}
.toast.is-leaving { animation: hub-fade-out 160ms var(--ease) forwards; }
.toast-msg { flex: 1; min-width: 0; }
.toast.tone-success { box-shadow: inset 3px 0 0 var(--success), var(--shadow-lg); }
.toast.tone-error { box-shadow: inset 3px 0 0 var(--danger), var(--shadow-lg); }
.toast .toast-action { color: #c9c2ff; font-weight: 650; }
.toast .toast-action:hover { background: rgba(255, 255, 255, 0.1); color: #fff; }
.toast .toast-close { color: rgba(255, 255, 255, 0.6); }
.toast .toast-close:hover { background: rgba(255, 255, 255, 0.1); color: #fff; }
@keyframes hub-toast-in { from { opacity: 0; transform: translateY(8px); } }

/* ------------------------------------------------------------------ command palette */

.palette-root { position: fixed; inset: 0; z-index: 110; display: flex; justify-content: center; align-items: flex-start; padding: 12vh var(--space-3) var(--space-3); }
.palette-backdrop { position: absolute; inset: 0; background: var(--scrim); animation: hub-fade 120ms var(--ease); }
.palette {
  position: relative; width: 100%; max-width: 660px; max-height: min(640px, 80vh);
  display: flex; flex-direction: column; overflow: hidden;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
  animation: hub-pop 140ms var(--ease);
}
.palette-input-row { display: flex; align-items: center; gap: var(--space-3); padding: 0 var(--space-4); height: 56px; border-bottom: 1px solid var(--border); flex: none; color: var(--text-3); }
.palette-input { flex: 1; min-width: 0; height: 100%; border: 0; background: transparent; font-size: var(--fs-md); color: var(--text); }
.palette-input::placeholder { color: var(--text-3); }
.palette-input:focus { outline: none; }
.palette-list { flex: 1; min-height: 0; overflow-y: auto; padding: 6px; overscroll-behavior: contain; }
.palette-group { padding: 10px 10px 4px; font-size: 11px; font-weight: 650; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-3); }
.palette-item { display: flex; align-items: center; gap: var(--space-3); min-height: 48px; padding: 6px 10px; border-radius: var(--radius); cursor: pointer; color: var(--text); text-decoration: none; }
.palette-item.is-active { background: var(--accent-soft); }
.palette-item-icon { width: 30px; height: 30px; flex: none; border-radius: 8px; background: var(--surface-2); color: var(--text-2); display: grid; place-items: center; font-size: 15px; line-height: 1; }
.palette-item.is-active .palette-item-icon { background: var(--surface); color: var(--accent-text); }
.palette-item-main { flex: 1; min-width: 0; }
.palette-item-title { font-weight: 550; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.palette-item-sub { font-size: var(--fs-xs); color: var(--text-3); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.palette-item-meta { flex: none; display: flex; align-items: center; gap: 10px; color: var(--text-3); font-size: var(--fs-xs); font-variant-numeric: tabular-nums; }
.palette-item-search .palette-item-icon { background: var(--accent-soft); color: var(--accent-text); }
.palette-empty { padding: var(--space-5) var(--space-4); text-align: center; color: var(--text-3); }
.palette-footer { flex: none; display: flex; align-items: center; gap: var(--space-4); padding: 8px var(--space-4); border-top: 1px solid var(--border); font-size: var(--fs-xs); color: var(--text-3); flex-wrap: wrap; }
.palette-footer span { display: inline-flex; align-items: center; gap: 5px; }
@media (max-width: 599px) {
  .palette-root { padding-top: var(--space-3); }
  .palette { max-height: calc(100dvh - 24px); }
  .palette-footer { display: none; }
}

/* ------------------------------------------------------------------ language switch (sidebar user menu)

   Vietnamese labels run roughly 25% longer than the English ones, so the sidebar rows that were sized
   for English get an explicit ellipsis here instead of pushing their counts out of the row. */

.user-menu-langs { display: flex; flex-direction: column; gap: 1px; padding-bottom: var(--space-1); margin-bottom: var(--space-1); border-bottom: 1px solid var(--border); }
.user-menu-label {
  display: flex; align-items: center; gap: 10px; min-height: 28px; padding: 0 var(--space-2);
  font-size: 11.5px; font-weight: 650; letter-spacing: 0.04em; text-transform: uppercase; color: var(--text-3);
}
.user-menu-label .icon { color: var(--text-3); }
.user-menu-lang { padding-left: calc(var(--space-2) + 25px); }
.user-menu-lang-name { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.user-menu-lang.is-active { color: var(--accent-text); font-weight: 600; }
.user-menu-lang .user-menu-check { flex: none; color: var(--accent-text); }

.nav-link > span:not(.nav-count) { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sidebar-more > summary > span:not(.more-count) { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sidebar-more-label { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.empty-title, .empty-text { overflow-wrap: anywhere; }
.badge { white-space: nowrap; }

/* ------------------------------------------------------------------ motion preferences */

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 1ms !important;
    scroll-behavior: auto !important;
  }
}