:root {
  --k12-shell-navy: #111b2e;
  --k12-shell-ink: #172033;
  --k12-shell-muted: #66758c;
  --k12-shell-blue: #216af4;
  --k12-shell-cyan: #45d6d0;
  --k12-shell-line: #d8e1ec;
  --k12-shell-surface: #ffffff;
  --k12-shell-bg: #f2f6fb;
  --k12-shell-sidebar: 262px;
}

body.cast-shell-mounted {
  background: var(--k12-shell-bg);
}

.cast-shell-mounted > [data-legacy-workspace-header],
.cast-shell-mounted [data-legacy-workspace-footer] {
  display: none !important;
}

.k12-classroom-shell {
  display: grid;
  grid-template-columns: var(--k12-shell-sidebar) minmax(0, 1fr);
  min-height: 100vh;
  color: var(--k12-shell-ink);
  background: var(--k12-shell-bg);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.k12-workspace-nav-toggle {
  position: fixed;
  left: -10000px;
  width: 1px;
  height: 1px;
  opacity: 0;
}

.k12-workspace-sidebar {
  position: sticky;
  z-index: 80;
  top: 0;
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow-x: hidden;
  overflow-y: auto;
  padding: 18px 14px;
  color: #d2dbea;
  background:
    radial-gradient(circle at 20% -5%, rgba(55, 118, 255, .21), transparent 16rem),
    linear-gradient(180deg, #101a2d 0%, #111827 62%);
  border-right: 1px solid rgba(255, 255, 255, .06);
  box-shadow: 8px 0 26px rgba(10, 20, 40, .08);
  scrollbar-color: #33405a transparent;
  scrollbar-width: thin;
}

.k12-workspace-sidebar > header {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 83px;
  margin-bottom: 12px;
  padding: 2px 7px 17px;
  border-bottom: 1px solid rgba(255, 255, 255, .11);
}

.k12-workspace-sidebar > header > a {
  min-width: 0;
  flex: 1;
}

.k12-workspace-sidebar img {
  display: block;
  width: 100%;
  max-height: 66px;
  object-fit: contain;
  object-position: left center;
}

.k12-workspace-sidebar button,
.k12-workspace-nav-close {
  display: grid;
  flex: 0 0 34px;
  width: 34px;
  height: 34px;
  place-items: center;
  padding: 0;
  color: #9fb0ca;
  border: 1px solid rgba(255, 255, 255, .11);
  border-radius: 9px;
  background: rgba(255, 255, 255, .055);
  cursor: pointer;
}

.k12-workspace-nav-close { display: none; }
.k12-workspace-sidebar button:hover { color: #fff; background: rgba(255, 255, 255, .11); }
.k12-workspace-sidebar button .material-symbols-outlined { font-size: 19px; }

.k12-workspace-sidebar > nav {
  display: grid;
  gap: 4px;
}

.k12-shell-nav-group {
  display: grid;
  gap: 4px;
}

.k12-shell-nav-group + .k12-shell-nav-group {
  margin-top: 9px;
  padding-top: 11px;
  border-top: 1px solid rgba(255, 255, 255, .075);
}

.k12-shell-nav-group > p {
  margin: 0;
  padding: 0 11px 3px;
  color: #71829d;
  font-size: 9px;
  font-weight: 800;
  letter-spacing: .105em;
  text-transform: uppercase;
}

.k12-shell-nav-group > a {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 42px;
  gap: 11px;
  padding: 9px 11px;
  color: #c5cee0;
  border: 1px solid transparent;
  border-radius: 9px;
  font-size: 13px;
  font-weight: 560;
  text-decoration: none;
  transition: .16s ease;
}

.k12-shell-nav-group > a > span:nth-child(2) {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.k12-shell-nav-group > a .material-symbols-outlined {
  flex: 0 0 auto;
  color: #8796ae;
  font-size: 21px;
}

.k12-shell-nav-group > a .external {
  margin-left: auto;
  font-size: 14px;
}

.k12-shell-nav-group > a:hover {
  color: #fff;
  background: rgba(255, 255, 255, .065);
  border-color: rgba(255, 255, 255, .07);
  transform: translateX(2px);
}

.k12-shell-nav-group > a.active {
  color: #fff;
  font-weight: 700;
  background: linear-gradient(135deg, rgba(41, 105, 244, .30), rgba(41, 105, 244, .16));
  border-color: rgba(104, 151, 255, .26);
  box-shadow: inset 3px 0 0 #6c9aff, 0 5px 14px rgba(0, 0, 0, .11);
}

.k12-shell-nav-group > a.active .material-symbols-outlined { color: #8fb2ff; font-variation-settings: "FILL" 1; }

.k12-shell-nav-loading { display: grid; gap: 9px; padding: 10px; }
.k12-shell-nav-loading span { height: 38px; border-radius: 9px; background: rgba(255, 255, 255, .06); animation: k12-shell-pulse 1.2s ease-in-out infinite; }
.k12-shell-nav-loading span:nth-child(2) { animation-delay: .12s; }
.k12-shell-nav-loading span:nth-child(3) { animation-delay: .24s; }

.k12-workspace-help {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: auto;
  padding: 11px;
  color: #c5cee0;
  border: 1px solid rgba(255, 255, 255, .08);
  border-radius: 11px;
  text-decoration: none;
}

.k12-workspace-help > .material-symbols-outlined { color: #7ca5ff; font-size: 22px; }
.k12-workspace-help strong, .k12-workspace-help small { display: block; }
.k12-workspace-help strong { font-size: 11px; }
.k12-workspace-help small { margin-top: 2px; color: #8290a7; font-size: 9px; }

.k12-workspace-column { min-width: 0; }

.k12-workspace-topbar {
  position: sticky;
  z-index: 70;
  top: 0;
  display: grid;
  grid-template-columns: minmax(176px, auto) minmax(220px, 420px) auto;
  align-items: center;
  min-height: 76px;
  gap: 22px;
  padding: 12px 30px;
  background: rgba(244, 247, 251, .92);
  border-bottom: 1px solid rgba(203, 211, 225, .78);
  backdrop-filter: blur(16px) saturate(140%);
}

.k12-workspace-title { display: grid; gap: 2px; }
.k12-workspace-title small { color: #5f6f86; font-size: 10px; font-weight: 800; letter-spacing: .095em; text-transform: uppercase; }
.k12-workspace-title strong { color: #111827; font-size: 23px; font-weight: 730; letter-spacing: -.035em; }

.k12-workspace-search { position: relative; display: flex; align-items: center; }
.k12-workspace-search > .material-symbols-outlined { position: absolute; z-index: 1; left: 13px; color: #718197; font-size: 19px; pointer-events: none; }
.k12-workspace-search input {
  width: 100%;
  min-height: 42px;
  padding: 0 18px 0 41px;
  color: #172033;
  border: 1px solid #d6deea;
  border-radius: 999px;
  outline: none;
  background: rgba(255, 255, 255, .96);
  box-shadow: 0 2px 6px rgba(17, 32, 54, .04);
}
.k12-workspace-search input:focus { border-color: #7aa8f8; box-shadow: 0 0 0 4px rgba(33, 106, 244, .12); }
.k12-workspace-search [data-shell-search-results] {
  position: absolute;
  z-index: 100;
  top: calc(100% + 9px);
  right: 0;
  left: 0;
  overflow: hidden;
  padding: 7px;
  background: #fff;
  border: 1px solid #d7e0ec;
  border-radius: 14px;
  box-shadow: 0 22px 55px rgba(20, 38, 64, .18);
}
.k12-workspace-search [data-shell-search-results] a { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 10px; padding: 10px; color: #26374d; border-radius: 9px; text-decoration: none; }
.k12-workspace-search [data-shell-search-results] a:hover { background: #edf4ff; }
.k12-workspace-search [data-shell-search-results] strong, .k12-workspace-search [data-shell-search-results] small { display: block; }
.k12-workspace-search [data-shell-search-results] strong { font-size: 12px; }
.k12-workspace-search [data-shell-search-results] small { margin-top: 2px; color: #58677c; font-size: 9px; }
.k12-workspace-search [data-shell-search-results] p { margin: 0; padding: 18px; color: #718197; font-size: 12px; text-align: center; }

.k12-workspace-actions { display: flex; align-items: center; justify-content: flex-end; gap: 9px; min-width: 0; }
.k12-workspace-status { display: inline-flex; align-items: center; gap: 7px; min-height: 28px; padding: 5px 10px; color: #8a5b0a; background: #fff7e8; border: 1px solid #efd69f; border-radius: 999px; font-size: 10px; font-weight: 800; white-space: nowrap; }
.k12-workspace-status i { width: 7px; height: 7px; border-radius: 50%; background: #d39826; }
.k12-workspace-status.online { color: #08745b; background: #eafaf4; border-color: #b7ead7; }
.k12-workspace-status.online i { background: #17b989; }
.k12-workspace-status.live { color: #9e2536; background: #fff0f2; border-color: #ffc7ce; }
.k12-workspace-status.live i { background: #e53950; box-shadow: 0 0 0 4px rgba(229, 57, 80, .12); }
.k12-workspace-actions select { max-width: 230px; min-height: 39px; padding: 0 34px 0 12px; color: #4a586d; border: 1px solid #d6deea; border-radius: 9px; background: #fff; }
.k12-workspace-icon, .k12-workspace-avatar { display: grid; flex: 0 0 38px; width: 38px; height: 38px; place-items: center; color: #43526a; border: 1px solid #d6deea; border-radius: 50%; background: #fff; text-decoration: none; }
.k12-workspace-avatar { color: #fff; font-size: 12px; font-weight: 850; background: linear-gradient(135deg, #216af4, #103eab); border: 2px solid #fff; box-shadow: 0 0 0 1px #cad3e2; }
.k12-workspace-return { display: inline-flex; align-items: center; min-height: 39px; gap: 6px; padding: 0 12px; color: #26364d; border: 1px solid #ccd7e5; border-radius: 9px; background: #fff; font-size: 12px; font-weight: 750; text-decoration: none; white-space: nowrap; }
.k12-workspace-return .material-symbols-outlined { font-size: 17px; }
.k12-workspace-menu { display: none; }

.k12-workspace-contextbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin: 22px 30px 0;
  padding: 15px 18px;
  background: #fff;
  border: 1px solid var(--k12-shell-line);
  border-radius: 14px;
  box-shadow: 0 7px 22px rgba(23, 42, 70, .045);
}
.k12-workspace-contextbar > div { display: flex; align-items: center; gap: 12px; }
.k12-workspace-contextbar > div > .material-symbols-outlined { display: grid; width: 40px; height: 40px; place-items: center; color: #1767e9; background: #e9f2ff; border-radius: 11px; }
.k12-workspace-contextbar small, .k12-workspace-contextbar strong { display: block; }
.k12-workspace-contextbar small { margin-bottom: 2px; color: #617188; font-size: 9px; font-weight: 800; letter-spacing: .075em; text-transform: uppercase; }
.k12-workspace-contextbar strong { color: #1b293e; font-size: 16px; }
.k12-focus-hint { display: inline-flex; align-items: center; gap: 5px; color: #66758c; font-size: 10px; }
.k12-focus-hint .material-symbols-outlined { font-size: 17px; }

.k12-workspace-stage { min-width: 0; padding: 20px 30px 38px; }
.k12-workspace-stage > main { min-width: 0; }

.k12-workspace-backdrop { display: none; }

/* Screen Share adopts the Cast workspace density while preserving the WebRTC surface. */
.cast-shell-mounted[data-cast-workspace="screen-share"] .sender-shell { overflow: visible; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .sender-intro {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(420px, .8fr);
  align-items: center;
  gap: clamp(30px, 5vw, 72px);
  max-width: none;
  padding: clamp(28px, 3.2vw, 44px);
  border-radius: 22px;
  background:
    radial-gradient(circle at 88% 12%, rgba(44, 127, 255, .24), transparent 31%),
    linear-gradient(125deg, #102743 0%, #0d3150 62%, #0d5768 100%);
  box-shadow: 0 16px 42px rgba(18, 44, 75, .11);
}
.cast-shell-mounted[data-cast-workspace="screen-share"] .sender-intro::after { border-radius: inherit; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .intro-copy h1 {
  max-width: 720px;
  font-family: inherit;
  font-size: clamp(38px, 4.2vw, 60px);
  font-weight: 760;
  line-height: 1.02;
  letter-spacing: -.05em;
}
.cast-shell-mounted[data-cast-workspace="screen-share"] .intro-copy > p:last-child { margin-top: 18px; font-size: 15px; line-height: 1.58; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; padding: 0; border: 0; background: transparent; box-shadow: none; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip > div { display: grid; min-height: 124px; grid-template-columns: 1fr; align-content: center; gap: 9px; padding: 16px; background: rgba(3, 18, 34, .28); border: 1px solid rgba(255, 255, 255, .1); border-radius: 14px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip > div + div { border-top: 1px solid rgba(255, 255, 255, .1); }
.cast-shell-mounted[data-cast-workspace="screen-share"] .trust-icon.material-symbols-outlined { display: grid; width: 38px; height: 38px; place-items: center; font-size: 21px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .share-workspace {
  width: 100%;
  margin: 18px auto 0;
  padding: clamp(24px, 3vw, 38px);
  border-radius: 20px;
  box-shadow: 0 12px 35px rgba(21, 45, 75, .08);
}
.cast-shell-mounted[data-cast-workspace="screen-share"] .workspace-topline { margin-bottom: 25px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .workspace-topline h2 { font-size: clamp(25px, 2.7vw, 32px); }
.cast-shell-mounted[data-cast-workspace="screen-share"] .workspace-grid { grid-template-columns: minmax(330px, .9fr) minmax(410px, 1.1fr); gap: clamp(28px, 4vw, 55px); }
.cast-shell-mounted[data-cast-workspace="screen-share"] .before-you-share { width: 100%; margin: 18px auto 0; padding: 23px 25px; background: #fff; border: 1px solid #dbe4ef; border-radius: 18px; box-shadow: 0 8px 25px rgba(21, 45, 75, .055); }
.cast-shell-mounted[data-cast-workspace="screen-share"] .before-you-share > div:first-child { margin-bottom: 16px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .before-you-share h2 { font-size: 22px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .tip-grid { gap: 12px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .tip-grid article { min-height: 108px; grid-template-columns: 38px 1fr; padding: 16px; box-shadow: none; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .tip-grid article > .material-symbols-outlined { display: grid; width: 36px; height: 36px; place-items: center; color: #1767e9; background: #e8f2ff; border-radius: 10px; font-size: 20px; }
.cast-shell-mounted[data-cast-workspace="screen-share"] .network-note { margin-top: 13px; }

.connection-options { margin: 0 0 17px; border: 1px solid #dce6f0; border-radius: 13px; background: #f7fafd; }
.connection-options > summary { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 10px; min-height: 58px; padding: 10px 13px; color: #263d55; cursor: pointer; list-style: none; }
.connection-options > summary::-webkit-details-marker { display: none; }
.connection-options > summary > .material-symbols-outlined:first-child { display: grid; width: 34px; height: 34px; place-items: center; color: #1767e9; background: #e7f1ff; border-radius: 9px; font-size: 19px; }
.connection-options > summary > .material-symbols-outlined:last-child { color: #63768b; font-size: 19px; transition: transform .17s ease; }
.connection-options[open] > summary > .material-symbols-outlined:last-child { transform: rotate(180deg); }
.connection-options > summary strong, .connection-options > summary small { display: block; }
.connection-options > summary strong { font-size: 12px; }
.connection-options > summary small { margin-top: 2px; color: #536477; font-size: 9px; font-weight: 600; }
.connection-options .stream-quality { margin: 0; padding: 0 13px 13px; border: 0; }
.connection-options .stream-quality legend { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }

body.cast-workspace-focus[data-cast-workspace="screen-share"] .k12-workspace-stage > main { display: block !important; padding-top: 76px; }
body.cast-workspace-focus[data-cast-workspace="screen-share"] .sender-intro,
body.cast-workspace-focus[data-cast-workspace="screen-share"] .before-you-share { display: none; }
body.cast-workspace-focus[data-cast-workspace="screen-share"] .share-workspace { width: min(1160px, calc(100% - 32px)); margin-top: 0; }

/* Live Canvas library is a first-class Cast workspace; the editor becomes focus mode. */
.cast-shell-mounted[data-cast-workspace="live-canvas"] .library-hero {
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 28px;
  padding: clamp(28px, 3.4vw, 46px);
  border-radius: 22px;
  background:
    radial-gradient(circle at 86% 12%, rgba(45, 130, 255, .24), transparent 28%),
    linear-gradient(125deg, #102743, #0d3150 62%, #0d5768);
  box-shadow: 0 16px 42px rgba(18, 44, 75, .11);
}
.cast-shell-mounted[data-cast-workspace="live-canvas"] .library-hero h1 { max-width: 760px; font-size: clamp(35px, 4vw, 56px); }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .library-hero p:not(.eyebrow) { margin-top: 17px; font-size: 15px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .hero-actions { min-width: 205px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .hero-actions button { display: flex; align-items: center; justify-content: center; gap: 8px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .hero-actions .material-symbols-outlined { font-size: 19px; }
.canvas-workspace-tabs { display: flex; align-items: center; gap: 4px; margin: 16px 0 0; padding: 4px; overflow-x: auto; background: #e8edf4; border: 1px solid #d7e0eb; border-radius: 12px; }
.canvas-workspace-tabs button { display: inline-flex; align-items: center; justify-content: center; min-height: 40px; flex: 1 0 auto; gap: 7px; padding: 0 15px; color: #52637a; background: transparent; border-radius: 9px; font-size: 11px; font-weight: 760; }
.canvas-workspace-tabs button:hover { color: #1e60cf; background: rgba(255, 255, 255, .7); }
.canvas-workspace-tabs button.active { color: #135ecf; background: #fff; box-shadow: 0 3px 9px rgba(28, 54, 88, .08); }
.canvas-workspace-tabs .material-symbols-outlined { font-size: 18px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .library-panel { max-width: none; min-height: 360px; padding: 25px 0 22px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .trust-row { max-width: none; gap: 12px; padding: 0 0 12px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .trust-row article { background: #fff; box-shadow: 0 7px 22px rgba(23, 42, 70, .045); }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .trust-row article > .material-symbols-outlined { display: grid; place-items: center; font-size: 20px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .primary-button,
.cast-shell-mounted[data-cast-workspace="live-canvas"] .secondary-button { display: inline-flex; align-items: center; justify-content: center; gap: 7px; }

body.cast-shell-mounted[data-cast-workspace="live-canvas"] .editor-view { top: 62px; height: calc(100dvh - 62px); }
body.cast-workspace-focus[data-cast-workspace="live-canvas"] .k12-workspace-stage > main { display: block !important; }
body.cast-workspace-focus[data-cast-workspace="live-canvas"] .editor-view { z-index: 100; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .editor-topbar { min-height: 60px; padding: 8px 14px; background: #16243a; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .editor-back { display: grid; place-items: center; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .editor-back .material-symbols-outlined { font-size: 20px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .editor-actions button { display: inline-flex; align-items: center; justify-content: center; gap: 6px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .editor-actions .material-symbols-outlined { font-size: 18px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .toolrail { width: 82px; gap: 4px; padding: 9px 8px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .toolrail > p { width: 100%; margin: 8px 0 2px; padding: 0 4px; color: #8997a8; font-size: 8px; font-weight: 850; letter-spacing: .09em; text-align: center; text-transform: uppercase; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .toolrail > p:first-child { margin-top: 0; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .toolrail button { width: 62px; min-height: 50px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .toolrail button .material-symbols-outlined { font-size: 21px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .toolrail button .line-tool-icon { transform: rotate(-28deg); }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .canvas-controls button,
.cast-shell-mounted[data-cast-workspace="live-canvas"] .add-page { display: inline-flex; align-items: center; justify-content: center; gap: 4px; }
.cast-shell-mounted[data-cast-workspace="live-canvas"] .canvas-controls button .material-symbols-outlined,
.cast-shell-mounted[data-cast-workspace="live-canvas"] .add-page .material-symbols-outlined { font-size: 16px; }

@media (min-width: 901px) {
  .k12-classroom-shell.navigation-collapsed { grid-template-columns: 76px minmax(0, 1fr); }
  .navigation-collapsed .k12-workspace-sidebar { padding-inline: 10px; }
  .navigation-collapsed .k12-workspace-sidebar > header { justify-content: center; }
  .navigation-collapsed .k12-workspace-sidebar > header > a,
  .navigation-collapsed .k12-shell-nav-group > p,
  .navigation-collapsed .k12-shell-nav-group > a > span:not(:first-child),
  .navigation-collapsed .k12-workspace-help > span:last-child { display: none; }
  .navigation-collapsed .k12-shell-nav-group > a,
  .navigation-collapsed .k12-workspace-help { justify-content: center; padding-inline: 8px; }
}

body.cast-workspace-focus .k12-classroom-shell { display: block; }
body.cast-workspace-focus .k12-workspace-sidebar,
body.cast-workspace-focus .k12-workspace-backdrop,
body.cast-workspace-focus .k12-workspace-contextbar,
body.cast-workspace-focus .k12-workspace-stage > main:not(:has(.editor-view:not([hidden]))) { display: none; }
body.cast-workspace-focus .k12-workspace-topbar { position: fixed; top: 0; right: 0; left: 0; min-height: 62px; grid-template-columns: minmax(180px, 1fr) auto; padding: 9px 16px; color: #fff; background: #101b2e; border-color: rgba(255, 255, 255, .09); }
body.cast-workspace-focus .k12-workspace-title small { color: #8194af; }
body.cast-workspace-focus .k12-workspace-title strong { color: #fff; font-size: 18px; }
body.cast-workspace-focus .k12-workspace-search,
body.cast-workspace-focus .k12-workspace-actions select,
body.cast-workspace-focus .k12-workspace-icon,
body.cast-workspace-focus .k12-workspace-avatar { display: none; }
body.cast-workspace-focus .k12-workspace-actions { grid-column: 2; }
body.cast-workspace-focus .k12-workspace-return { color: #dbe7f5; border-color: rgba(255, 255, 255, .15); background: rgba(255, 255, 255, .08); }
body.cast-workspace-focus .k12-workspace-stage { padding: 0; }

.k12-shell-announcements { position: fixed; z-index: 3000; right: 20px; bottom: 20px; display: grid; width: min(370px, calc(100vw - 40px)); gap: 9px; }
.k12-shell-notice { display: grid; gap: 4px; padding: 14px 16px; color: #115f4c; background: #edfaf6; border: 1px solid #b9e8d8; border-radius: 12px; box-shadow: 0 15px 40px rgba(16, 35, 60, .18); }
.k12-shell-notice.error { color: #a52b3c; background: #fff1f3; border-color: #f2c5cd; }
.k12-shell-notice strong { font-size: 13px; }
.k12-shell-notice span { font-size: 11px; line-height: 1.45; }

@media (max-width: 1180px) {
  .k12-workspace-topbar { grid-template-columns: minmax(160px, auto) minmax(180px, 1fr) auto; gap: 12px; padding-inline: 20px; }
  .k12-workspace-actions select { display: none; }
  .k12-workspace-contextbar { margin-inline: 20px; }
  .k12-workspace-stage { padding-inline: 20px; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .sender-intro { grid-template-columns: 1fr; gap: 24px; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip > div { min-height: 105px; }
}

@media (max-width: 900px) {
  .k12-classroom-shell { display: block; }
  .k12-workspace-sidebar { position: fixed; left: 0; width: min(310px, 88vw); transform: translateX(-105%); transition: transform .2s ease; }
  .k12-workspace-nav-toggle:checked ~ .k12-workspace-sidebar { transform: translateX(0); }
  .k12-workspace-nav-toggle:checked ~ .k12-workspace-backdrop { position: fixed; z-index: 75; inset: 0; display: block; background: rgba(7, 17, 31, .48); backdrop-filter: blur(2px); }
  .k12-workspace-sidebar button { display: none; }
  .k12-workspace-nav-close { display: grid; }
  .k12-workspace-topbar { grid-template-columns: auto minmax(0, 1fr) auto; }
  .k12-workspace-menu { display: grid; width: 38px; height: 38px; place-items: center; color: #3b4c63; border: 1px solid #d6deea; border-radius: 9px; background: #fff; cursor: pointer; }
  .k12-workspace-search { display: none; }
  .k12-workspace-actions { grid-column: 3; }
  .k12-workspace-status, .k12-workspace-icon, .k12-workspace-avatar { display: none; }
  .k12-workspace-contextbar { margin-top: 14px; }
  .k12-focus-hint { display: none; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .display-panel { display: block; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .selected-display,
  .cast-shell-mounted[data-cast-workspace="screen-share"] .presenter-actions { margin-top: 17px; }
  .cast-shell-mounted[data-cast-workspace="live-canvas"] .library-hero { grid-template-columns: 1fr; }
  .cast-shell-mounted[data-cast-workspace="live-canvas"] .hero-actions { display: flex; min-width: 0; flex-wrap: wrap; }
}

@media (max-width: 620px) {
  .k12-workspace-topbar { min-height: 66px; padding: 9px 12px; }
  .k12-workspace-title small { font-size: 8px; }
  .k12-workspace-title strong { font-size: 18px; }
  .k12-workspace-return { width: 38px; padding: 0; justify-content: center; }
  .k12-workspace-return > span:last-child { display: none; }
  .k12-workspace-contextbar { margin: 12px 12px 0; padding: 12px; }
  .k12-workspace-stage { padding: 12px 12px 28px; }
  body.cast-workspace-focus .k12-workspace-topbar { grid-template-columns: minmax(0, 1fr) auto; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .sender-intro { padding: 24px 20px; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .intro-copy h1 { font-size: 36px; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .workspace-grid { grid-template-columns: 1fr; gap: 24px; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip { grid-template-columns: 1fr; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip > div { min-height: 82px; grid-template-columns: 38px minmax(0, 1fr); }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .trust-strip > div + div { border-left: 1px solid rgba(255, 255, 255, .1); }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .share-workspace { padding: 21px 16px; }
  .cast-shell-mounted[data-cast-workspace="screen-share"] .before-you-share { padding: 20px 16px; }
  .cast-shell-mounted[data-cast-workspace="live-canvas"] .library-hero { padding: 25px 20px; }
  .cast-shell-mounted[data-cast-workspace="live-canvas"] .library-hero h1 { font-size: 36px; }
  .cast-shell-mounted[data-cast-workspace="live-canvas"] .hero-actions { display: grid; width: 100%; }
  .canvas-workspace-tabs button { flex-basis: auto; }
}

@media (prefers-reduced-motion: reduce) {
  .k12-workspace-sidebar, .k12-shell-nav-loading span { animation: none; transition: none; }
}

@keyframes k12-shell-pulse { 50% { opacity: .45; } }