:root {
  color-scheme:light;
  --ink:#172a42;
  --muted:#52647a;
  --line:#dae3ef;
  --blue:#255acb;
  --blue-soft:#eef4ff;
  --surface:#fff;
  --green:#126b50;
  --orange:#995112;
  --purple:#6943a4;
  --radius:20px;
  font-family:Inter,"Segoe UI","Microsoft YaHei","PingFang SC",system-ui,sans-serif;
  color:var(--ink);
  background:#f4f7fb;
  font-synthesis:none
}

* {
  box-sizing:border-box
}

body {
  margin:0
}

a {
  color:inherit
}

button,input,textarea {
  font:inherit
}

button,a,input,textarea {
  -webkit-tap-highlight-color:transparent
}

button {
  cursor:pointer
}

button:disabled {
  cursor:wait;
  opacity:.55
}

button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible {
  outline:3px solid #255acb;
  outline-offset:4px
}

button,input,textarea {
  border-radius:11px
}

h1,h2,h3,p {
  margin-top:0
}

h1,h2,h3 {
  line-height:1.35;
  letter-spacing:-.025em
}

h1 {
  font-size:clamp(1.75rem,3vw,2.6rem)
}

h2 {
  font-size:1.35rem
}

h3 {
  font-size:1.06rem
}

p {
  line-height:1.75
}

ul,ol {
  line-height:1.8;
  padding-left:1.25rem
}

small,.small {
  font-size:.82rem
}

.subtle {
  color:var(--muted)
}

.center {
  text-align:center
}

.full {
  width:100%
}

.optional {
  font-size:.78rem;
  font-weight:400;
  color:var(--muted)
}

[hidden] {
  display:none!important
}

.screen-reader-only {
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  overflow:hidden;
  clip:rect(0,0,0,0);
  white-space:nowrap;
  border:0
}

.skip-link {
  position:fixed;
  top:12px;
  left:12px;
  transform:translateY(-200%);
  z-index:30;
  background:#fff;
  padding:12px 18px;
  border:2px solid var(--blue);
  border-radius:10px
}

.skip-link:focus {
  transform:none
}

.button {
  white-space:nowrap
}

.input-with-button .button {
  flex-shrink:0
}

.app-header {
  height:94px;
  max-width:1440px;
  padding:18px 48px;
  margin:auto;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
  border-bottom:1px solid var(--line)
}

.brand {
  display:flex;
  align-items:center;
  gap:10px;
  font-size:1.32rem;
  font-weight:750;
  text-decoration:none;
  white-space:nowrap
}

.brand-mark {
  display:grid;
  place-items:center;
  width:42px;
  height:42px;
  border-radius:13px;
  background:var(--blue);
  color:#fff;
  font-size:2.5rem;
  line-height:1
}

.brand-accent {
  color:var(--blue)
}

.brand small {
  display:block;
  font-size:.66rem;
  letter-spacing:.2em;
  font-weight:500;
  color:var(--muted);
  margin-top:3px
}

.app-header nav {
  display:flex;
  align-items:center;
  gap:26px;
  font-size:.87rem
}

.app-header nav a {
  text-decoration:none
}

.app-header nav a:hover {
  color:var(--blue)
}

.website-link {
  color:var(--muted);
  border-left:1px solid var(--line);
  padding-left:26px
}

.role-label {
  color:var(--blue);
  font-weight:600
}

.app-footer {
  max-width:1320px;
  padding:36px 36px 24px;
  margin:auto;
  border-top:1px solid var(--line);
  color:var(--muted);
  font-size:.76rem
}

.app-footer p {
  margin:0 0 5px
}

.eyebrow {
  display:block;
  color:var(--blue);
  font-size:.79rem;
  letter-spacing:.09em;
  font-weight:650;
  margin-bottom:12px
}

.button {
  border:1px solid transparent;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:14px;
  min-height:44px;
  padding:10px 18px;
  line-height:1.4;
  font-weight:600;
  text-decoration:none;
  font-size:.9rem;
  border-radius:11px
}

.button.large {
  min-height:54px;
  padding:14px 24px
}

.button.primary {
  background:var(--blue);
  color:#fff
}

.button.primary:hover {
  background:#1749b0
}

.button.secondary {
  background:#fff;
  border-color:#c5d2e3;
  color:var(--ink)
}

.button.secondary:hover {
  background:#edf3fb
}

.button.danger-outline {
  background:#fff;
  color:#a93737;
  border-color:#edcece
}

.button.danger {
  background:#b63c3c;
  color:#fff
}

.text-button {
  border:0;
  background:transparent;
  color:var(--blue);
  min-height:44px;
  padding:8px;
  font-size:.86rem;
  font-weight:600
}

.text-button:hover {
  text-decoration:underline
}

.card {
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:var(--radius);
  padding:28px;
  box-shadow:0 7px 28px #1b375407
}

.notice {
  padding:14px 18px;
  border:1px solid #bbd0f7;
  background:#edf4ff;
  color:#244a87;
  border-radius:12px;
  margin-bottom:20px;
  line-height:1.6;
  overflow-wrap:anywhere
}

.notice.error {
  color:#92342f;
  border-color:#eac2c0;
  background:#fff2f0
}

.notice.success {
  color:#126347;
  border-color:#b5dbc9;
  background:#eff9f4
}

.connection-state {
  font-size:.79rem;
  color:var(--muted);
  display:inline-flex;
  align-items:center;
  gap:7px;
  white-space:nowrap
}

.connection-state::before {
  content:"";
  width:7px;
  height:7px;
  display:block;
  background:#8596aa;
  border-radius:50%
}

.connection-state.online::before {
  background:#168060
}

.connection-state.offline {
  color:#995112
}

.connection-state.offline::before {
  background:#b87918
}

.status-pill {
  display:inline-flex;
  align-items:center;
  justify-content:center;
  white-space:nowrap;
  border-radius:30px;
  background:#e9f6ee;
  color:#126b50;
  font-size:.79rem;
  font-weight:650;
  padding:7px 12px
}

.status-pill.paused {
  background:#fff3dc;
  color:#995112
}

.status-pill.closed {
  background:#edf1f5;
  color:#52647a
}

.empty-state {
  color:var(--muted);
  font-size:.9rem;
  line-height:1.7;
  padding:18px 0;
  margin:0
}

.bar-track {
  background:#edf1f6;
  height:7px;
  border-radius:20px;
  overflow:hidden
}

.bar {
  display:block;
  height:100%;
  border-radius:20px;
  transition:width .3s ease
}

.green {
  --choice-color:var(--green);
  --choice-bg:#edf8f2;
  --choice-line:#a7cbbb
}

.blue {
  --choice-color:var(--blue);
  --choice-bg:#eef4ff;
  --choice-line:#aec4f1
}

.orange {
  --choice-color:var(--orange);
  --choice-bg:#fff6e8;
  --choice-line:#dec196
}

.purple {
  --choice-color:var(--purple);
  --choice-bg:#f5f0fc;
  --choice-line:#ccbbe7
}

.bar.green {
  background:var(--green)
}

.bar.blue {
  background:var(--blue)
}

.bar.orange {
  background:var(--orange)
}

.bar.purple {
  background:var(--purple)
}

.landing-main {
  max-width:1280px;
  margin:auto;
  padding:70px 36px
}

.landing-hero {
  display:grid;
  grid-template-columns:1.08fr .92fr;
  gap:75px;
  align-items:center;
  padding:25px 0 68px
}

.hero-copy h1 {
  font-size:clamp(2.3rem,4vw,3.8rem);
  line-height:1.25;
  letter-spacing:-.055em;
  margin-bottom:24px
}

.hero-copy h1 span {
  color:var(--blue)
}

.hero-description {
  max-width:530px;
  color:var(--muted);
  font-size:1.06rem;
  line-height:1.9
}

.hero-actions {
  display:flex;
  gap:14px;
  margin:32px 0 18px
}

.hero-copy>.subtle {
  font-size:.8rem
}

.example-panel {
  background:#fff;
  padding:32px;
  border:1px solid #d5e0f2;
  border-radius:25px;
  box-shadow:0 20px 80px #31598d10
}

.example-top {
  display:flex;
  align-items:center;
  justify-content:space-between;
  margin-bottom:28px;
  font-size:.76rem
}

.example-panel h2 {
  font-size:1.22rem;
  margin-bottom:6px
}

.example-row {
  display:grid;
  grid-template-columns:1fr auto;
  gap:10px;
  margin-top:24px;
  font-size:.86rem
}

.example-row strong {
  font-size:1.05rem
}

.example-row .bar-track {
  grid-column:1/-1
}

.example-note {
  margin:28px 0 0;
  padding-top:20px;
  border-top:1px solid var(--line);
  font-size:.8rem;
  color:var(--muted)
}

.how-section {
  padding:40px 0 54px;
  border-top:1px solid var(--line)
}

.section-heading h2 {
  margin-bottom:18px
}

.step-grid {
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:38px;
  list-style:none;
  padding:0;
  margin:30px 0 0
}

.step-grid p {
  font-size:.91rem;
  color:var(--muted)
}

.step-number {
  color:var(--blue);
  font-size:.8rem;
  font-weight:700;
  display:block;
  margin-bottom:20px
}

.guide-card {
  border:1px solid var(--line);
  border-radius:20px;
  background:#ecf1f8;
  padding:32px;
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:40px
}

.guide-card h2 {
  font-size:1.18rem
}

.guide-card p {
  margin:0;
  font-size:.9rem;
  color:var(--muted)
}

.guide-card ul {
  font-size:.85rem;
  color:var(--muted);
  margin:0
}

.teacher-main {
  max-width:1440px;
  margin:auto;
  padding:36px 48px 54px
}

.page-heading {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:25px;
  margin-bottom:28px
}

.page-heading h1 {
  font-size:1.8rem;
  margin-bottom:0
}

.page-heading .eyebrow {
  margin-bottom:6px
}

.workspace {
  display:grid;
  grid-template-columns:305px minmax(0,1fr);
  gap:24px;
  align-items:start
}

.teacher-sidebar {
  display:grid;
  gap:20px
}

.setup-card,.recent-card {
  padding:23px
}

.setup-card h2,.recent-card h2 {
  font-size:1.04rem;
  margin-bottom:8px
}

.setup-card>.subtle {
  font-size:.82rem
}

.setup-card form {
  display:grid;
  gap:10px
}

.setup-card form label {
  font-size:.82rem;
  font-weight:600;
  margin-top:4px
}

input,textarea {
  display:block;
  max-width:100%;
  width:100%;
  background:#fff;
  color:var(--ink);
  border:1px solid #c4d0df;
  padding:12px;
  line-height:1.5;
  outline-offset:2px
}

input::placeholder,textarea::placeholder {
  color:#78899c;
  font-size:.84rem
}

textarea {
  resize:vertical;
  min-height:85px
}

.setup-card form .button {
  margin-top:8px
}

.setup-card>.small {
  margin:16px 0 0
}

.section-heading.compact {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:10px
}

.section-heading.compact h2 {
  margin:0
}

.classroom-list {
  display:grid;
  gap:8px
}

.classroom-item {
  display:block;
  width:100%;
  border:1px solid var(--line);
  background:#fff;
  text-align:left;
  padding:12px;
  border-radius:12px;
  color:var(--ink)
}

.classroom-item:hover,.classroom-item.selected {
  border-color:#98b5e9;
  background:#f2f6ff
}

.classroom-item strong {
  display:block;
  font-size:.84rem;
  white-space:normal;
  overflow-wrap:anywhere;
  margin-bottom:7px
}

.classroom-item .room-meta {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:6px;
  color:var(--muted);
  font-size:.73rem
}

.classroom-item .status-pill {
  font-size:.65rem;
  padding:3px 6px
}

.welcome-card {
  min-height:460px;
  text-align:center;
  display:flex;
  flex-direction:column;
  justify-content:center;
  align-items:center;
  padding:48px
}

.welcome-mark {
  display:grid;
  place-items:center;
  width:80px;
  height:80px;
  background:var(--blue-soft);
  color:var(--blue);
  border-radius:25px;
  font-size:4rem;
  margin-bottom:24px
}

.welcome-card h2 {
  font-size:1.6rem
}

.welcome-card p {
  max-width:400px;
  color:var(--muted)
}

.welcome-card ol {
  text-align:left;
  color:var(--muted);
  font-size:.89rem
}

.teacher-content {
  min-width:0
}

#classroom-panel {
  display:grid;
  gap:20px
}

.room-heading {
  display:flex;
  align-items:start;
  justify-content:space-between;
  gap:24px
}

.room-heading h2 {
  font-size:1.3rem;
  overflow-wrap:anywhere;
  margin-bottom:0
}

.room-heading .eyebrow {
  font-size:.7rem;
  margin-bottom:6px
}

.room-heading-actions {
  display:flex;
  align-items:center;
  gap:10px
}

.join-display {
  display:grid;
  grid-template-columns:auto 1fr;
  gap:35px;
  border-bottom:1px solid var(--line);
  padding:26px 0 22px
}

.class-code {
  display:block;
  letter-spacing:.12em;
  color:var(--blue);
  font-size:clamp(2rem,3vw,2.8rem);
  font-variant-numeric:tabular-nums;
  line-height:1.45
}

.join-share {
  min-width:0;
  align-self:center
}

.join-share label {
  display:block;
  margin-bottom:6px
}

.input-with-button {
  display:flex;
  align-items:center;
  gap:8px
}

.input-with-button input {
  background:#f7f9fc;
  font-size:.79rem;
  min-width:0
}

.join-share p {
  margin:7px 0 0;
  overflow-wrap:anywhere
}

.round-header {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:24px;
  padding:25px 0 15px
}

.round-label {
  font-size:.8rem;
  color:var(--blue);
  display:block;
  margin-bottom:7px;
  font-weight:650
}

.round-header h3 {
  font-size:1.22rem;
  margin-bottom:0;
  white-space:pre-line;
  overflow-wrap:anywhere
}

.total-display {
  text-align:right;
  min-width:84px
}

.total-display strong {
  display:block;
  font-size:2.35rem;
  line-height:1.15;
  font-variant-numeric:tabular-nums
}

.total-display span {
  font-size:.74rem;
  color:var(--muted)
}

.stats-grid {
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:12px;
  margin-top:10px
}

.stat-card {
  border:1px solid var(--line);
  border-top:3px solid var(--choice-color);
  border-radius:13px;
  padding:16px 13px;
  background:var(--choice-bg)
}

.stat-card h4 {
  font-size:.78rem;
  font-weight:650;
  color:var(--choice-color);
  margin:0 0 17px
}

.stat-numbers {
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:5px;
  margin-bottom:14px
}

.stat-numbers strong {
  font-size:1.85rem;
  font-variant-numeric:tabular-nums;
  line-height:1
}

.stat-numbers span {
  font-size:.76rem;
  color:var(--muted)
}

.stat-card .bar {
  background:var(--choice-color)
}

.projection-note {
  margin:22px 0 0
}

.controls-card {
  padding:22px 28px
}

.controls-card h3 {
  margin-bottom:7px
}

.controls-card p {
  margin-bottom:14px
}

.action-buttons {
  display:flex;
  flex-wrap:wrap;
  gap:9px
}

.review-card {
  padding-top:14px
}

.review-tabs {
  display:flex;
  gap:25px;
  border-bottom:1px solid var(--line);
  margin-bottom:24px
}

.review-tabs button {
  background:transparent;
  border:0;
  border-radius:0;
  padding:15px 0;
  font-weight:600;
  color:var(--muted);
  border-bottom:2px solid transparent
}

.review-tabs button[aria-selected="true"] {
  color:var(--blue);
  border-bottom-color:var(--blue)
}

.history-round {
  padding:18px 0;
  border-top:1px solid var(--line)
}

.history-round:first-child {
  border-top:0
}

.history-heading {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px
}

.history-heading h3 {
  margin-bottom:6px
}

.history-heading span {
  font-size:.77rem;
  color:var(--muted);
  white-space:nowrap
}

.history-question {
  color:var(--muted);
  font-size:.87rem;
  margin:0 0 14px;
  white-space:pre-line;
  overflow-wrap:anywhere
}

.history-stats {
  display:grid;
  grid-template-columns:repeat(2,1fr);
  gap:15px 24px
}

.history-stat {
  font-size:.77rem;
  display:grid;
  grid-template-columns:1fr auto;
  gap:7px
}

.history-stat .bar-track {
  grid-column:1/-1;
  height:5px
}

.history-stat .bar {
  background:var(--choice-color)
}

.history-stat>span:first-child {
  color:var(--choice-color)
}

.summary-grid {
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:18px;
  margin-bottom:20px
}

.summary-grid>div {
  background:#f5f8fc;
  border:1px solid var(--line);
  padding:20px 16px;
  border-radius:14px
}

.summary-grid strong {
  font-size:1.9rem;
  display:block;
  margin-bottom:5px
}

.summary-grid span {
  font-size:.78rem;
  color:var(--muted)
}

.trend-legend {
  display:flex;
  gap:14px;
  flex-wrap:wrap;
  margin:18px 0 22px;
  font-size:.75rem
}

.legend-item {
  display:flex;
  align-items:center;
  gap:6px
}

.legend-dot {
  width:9px;
  height:9px;
  border-radius:50%;
  background:var(--choice-color)
}

.trend-row {
  display:grid;
  grid-template-columns:54px 1fr 56px;
  gap:12px;
  align-items:center;
  margin-bottom:16px;
  font-size:.8rem
}

.trend-track {
  display:flex;
  height:24px;
  border-radius:5px;
  overflow:hidden;
  background:#edf1f6
}

.trend-segment {
  background:var(--choice-color);
  display:grid;
  place-items:center;
  color:#fff;
  font-size:.65rem;
  font-variant-numeric:tabular-nums
}

.trend-row>span:last-child {
  text-align:right;
  color:var(--muted)
}

.action-dialog {
  width:min(92vw,480px);
  border:1px solid var(--line);
  border-radius:20px;
  padding:28px;
  color:var(--ink);
  box-shadow:0 30px 100px #14253f40
}

.action-dialog::backdrop {
  background:#162e4c80;
  backdrop-filter:blur(3px)
}

.action-dialog h2 {
  font-size:1.3rem
}

.action-dialog p {
  color:var(--muted);
  font-size:.91rem
}

.action-dialog label {
  display:block;
  margin-bottom:10px;
  font-size:.87rem;
  font-weight:600
}

.dialog-actions {
  display:flex;
  justify-content:flex-end;
  gap:10px;
  margin-top:25px
}

.projection-area:fullscreen {
  border:0;
  border-radius:0;
  padding:4vh 5vw;
  background:#fff;
  overflow:auto;
  display:flex;
  flex-direction:column;
  justify-content:center
}

.projection-area:fullscreen .room-heading h2 {
  font-size:2rem
}

.projection-area:fullscreen .class-code {
  font-size:clamp(3rem,6vw,6rem)
}

.projection-area:fullscreen .round-header h3 {
  font-size:clamp(1.5rem,3vw,2.6rem)
}

.projection-area:fullscreen .stat-card {
  padding:28px 22px
}

.projection-area:fullscreen .stat-card h4 {
  font-size:clamp(1rem,1.8vw,1.6rem)
}

.projection-area:fullscreen .stat-numbers strong {
  font-size:clamp(3rem,5vw,5rem)
}

.projection-area:fullscreen .stat-numbers span {
  font-size:1.2rem
}

.projection-area:fullscreen .total-display strong {
  font-size:3.7rem
}

.projection-area:fullscreen .join-share input {
  font-size:1.1rem
}

.projection-area:fullscreen .small,.projection-area:fullscreen .total-display span {
  font-size:1rem
}

.projection-area:fullscreen .connection-state {
  font-size:1rem
}

.student-main {
  max-width:680px;
  padding:55px 26px 65px;
  margin:auto
}

.join-card {
  max-width:480px;
  margin:20px auto;
  padding:42px;
  text-align:center
}

.join-card h1 {
  margin-bottom:12px
}

.join-card form {
  margin-top:28px
}

.code-input {
  text-align:center;
  font-size:2.25rem;
  font-weight:650;
  letter-spacing:.18em;
  min-height:80px;
  font-variant-numeric:tabular-nums
}

.code-input::placeholder {
  font-size:2.25rem;
  letter-spacing:.18em;
  color:#a9b5c4
}

.privacy-note {
  font-size:.77rem;
  line-height:1.75;
  color:var(--muted);
  border-top:1px solid var(--line);
  padding-top:20px;
  margin:25px 0 0
}

.student-room-header {
  display:flex;
  align-items:flex-start;
  justify-content:space-between;
  gap:16px;
  margin-bottom:15px
}

.student-room-header h1 {
  font-size:1.45rem;
  margin:0;
  overflow-wrap:anywhere
}

.student-room-header .eyebrow {
  font-size:.77rem;
  margin-bottom:7px
}

.student-meta {
  display:flex;
  align-items:center;
  justify-content:space-between;
  margin-bottom:20px
}

.feedback-card {
  padding:32px
}

.feedback-card h2 {
  font-size:1.45rem;
  white-space:pre-line;
  overflow-wrap:anywhere
}

.feedback-card>.subtle {
  font-size:.88rem
}

.feedback-card fieldset {
  padding:0;
  border:0;
  margin:24px 0
}

.feedback-grid {
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:14px
}

.feedback-option {
  display:grid;
  grid-template-columns:1fr auto;
  align-items:start;
  position:relative;
  padding:18px;
  border:2px solid var(--line);
  border-radius:15px;
  background:#fff;
  cursor:pointer
}

.feedback-option:has(input:checked) {
  background:var(--choice-bg);
  border-color:var(--choice-color)
}

.feedback-option:has(input:focus-visible) {
  outline:3px solid var(--blue);
  outline-offset:3px
}

.feedback-option input {
  position:absolute;
  opacity:0;
  width:1px;
  height:1px;
  margin:0
}

.choice-icon {
  font-size:1.65rem;
  color:var(--choice-color);
  grid-column:1;
  margin-bottom:12px
}

.feedback-option strong {
  font-size:.94rem;
  grid-column:1
}

.feedback-option small {
  color:var(--muted);
  font-size:.75rem;
  grid-column:1;
  margin-top:6px
}

.choice-check {
  grid-column:2;
  grid-row:1;
  border:1px solid #b9c6d8;
  border-radius:50%;
  width:22px;
  height:22px;
  text-align:center;
  color:transparent;
  font-size:.78rem;
  padding-top:2px
}

.feedback-option:has(input:checked) .choice-check {
  background:var(--choice-color);
  border-color:var(--choice-color);
  color:#fff
}

.feedback-option:has(input:disabled) {
  opacity:.65;
  cursor:wait
}

.student-state {
  text-align:center;
  padding:34px 16px;
  background:#f4f8fd;
  border-radius:16px;
  margin-top:25px
}

.state-icon {
  width:60px;
  height:60px;
  display:grid;
  place-items:center;
  background:#e1f2e9;
  color:var(--green);
  font-size:2rem;
  border-radius:50%;
  margin:0 auto 18px
}

.student-state.paused .state-icon {
  background:#fff0d6;
  color:var(--orange)
}

.student-state.closed .state-icon {
  background:#e8eef5;
  color:var(--muted)
}

.student-state h3 {
  font-size:1.17rem;
  margin-bottom:8px
}

.student-state p {
  font-size:.88rem;
  color:var(--muted);
  margin-bottom:0;
  white-space:pre-line
}

@media(max-width:1100px) {
  .app-header {
    padding-inline:30px
  }
  .teacher-main {
    padding-inline:30px
  }
  .workspace {
    grid-template-columns:270px minmax(0,1fr);
    gap:18px
  }
  .card {
    padding:22px
  }
  .stats-grid {
    grid-template-columns:repeat(2,minmax(0,1fr))
  }
  .join-display {
    grid-template-columns:1fr;
    gap:12px
  }
  .class-code {
    font-size:2.8rem
  }
  .landing-hero {
    gap:35px
  }
  .projection-area:fullscreen .stats-grid {
    grid-template-columns:repeat(4,minmax(0,1fr))
  }
  .projection-area:fullscreen .join-display {
    grid-template-columns:auto 1fr;
    gap:50px
  }
}

@media(max-width:760px) {
  .app-header {
    height:auto;
    min-height:80px;
    padding:16px 20px;
    gap:12px
  }
  .app-header nav {
    gap:12px;
    font-size:.76rem
  }
  .app-header nav .website-link {
    padding-left:12px
  }
  .brand {
    font-size:1.06rem;
    gap:7px
  }
  .brand-mark {
    width:34px;
    height:34px;
    font-size:2rem
  }
  .brand small {
    font-size:.56rem
  }
  .role-label {
    display:none
  }
  .landing-main {
    padding:36px 24px
  }
  .landing-hero {
    grid-template-columns:1fr;
    gap:32px;
    padding:0 0 36px
  }
  .hero-copy h1 {
    font-size:2.6rem
  }
  .hero-description {
    font-size:.95rem
  }
  .hero-actions {
    margin-top:24px
  }
  .example-panel {
    padding:25px
  }
  .step-grid {
    grid-template-columns:1fr;
    gap:16px;
    margin-top:24px
  }
  .step-grid li {
    position:relative;
    padding-left:40px
  }
  .step-number {
    position:absolute;
    left:0;
    top:2px
  }
  .step-grid h3 {
    margin-bottom:9px
  }
  .step-grid p {
    margin-bottom:6px
  }
  .guide-card {
    grid-template-columns:1fr;
    gap:20px;
    padding:25px
  }
  .teacher-main {
    padding:25px 20px 36px
  }
  .page-heading {
    align-items:flex-start;
    gap:12px
  }
  .page-heading h1 {
    font-size:1.4rem
  }
  .page-heading .eyebrow {
    font-size:.7rem
  }
  .page-heading>.connection-state {
    margin-top:8px;
    font-size:.7rem
  }
  .workspace {
    display:flex;
    flex-direction:column
  }
  .teacher-sidebar,.teacher-content {
    width:100%
  }
  .teacher-sidebar {
    display:flex;
    flex-direction:column
  }
  .setup-card form {
    grid-template-columns:1fr 1fr;
    column-gap:14px
  }
  .setup-card form label,.setup-card form input,.setup-card form textarea,.setup-card form button {
    grid-column:1/-1
  }
  .recent-card {
    order:2
  }
  .classroom-list {
    grid-template-columns:repeat(2,minmax(0,1fr));
    max-height:220px;
    overflow:auto
  }
  .recent-card>.small {
    margin-bottom:10px
  }
  .welcome-card {
    min-height:330px;
    padding:28px
  }
  .room-heading {
    gap:12px
  }
  .room-heading h2 {
    font-size:1.1rem
  }
  .room-heading-actions {
    flex-direction:column;
    align-items:flex-end;
    gap:0
  }
  .room-heading-actions .text-button {
    font-size:.74rem
  }
  .class-code {
    font-size:2.9rem
  }
  .round-header h3 {
    font-size:1.13rem
  }
  .total-display strong {
    font-size:2.05rem
  }
  .stat-card h4 {
    font-size:.86rem
  }
  .stat-numbers strong {
    font-size:2rem
  }
  .stats-grid {
    gap:12px
  }
  .review-card {
    padding:18px
  }
  .summary-grid {
    gap:8px
  }
  .summary-grid>div {
    padding:16px 10px
  }
  .summary-grid strong {
    font-size:1.65rem
  }
  .summary-grid span {
    font-size:.69rem
  }
  .history-stats {
    gap:14px
  }
  .history-heading span {
    font-size:.68rem
  }
  .trend-row {
    grid-template-columns:48px 1fr 45px;
    gap:8px;
    font-size:.72rem
  }
  .student-main {
    padding:28px 18px 44px
  }
  .join-card {
    padding:30px 24px;
    margin:15px auto
  }
  .feedback-card {
    padding:26px 20px
  }
  .feedback-option {
    padding:15px 12px
  }
  .feedback-option strong {
    font-size:.87rem
  }
  .student-room-header h1 {
    font-size:1.3rem
  }
  .app-footer {
    padding:24px 22px 20px
  }
}

@media(max-width:420px) {
  .app-header nav a:not(.website-link) {
    display:none
  }
  .app-header .website-link {
    border:0;
    padding:0
  }
  .classroom-list {
    grid-template-columns:1fr
  }
  .hero-actions .button {
    padding-inline:18px
  }
  .hero-copy h1 {
    font-size:2.2rem
  }
  .room-heading-actions .status-pill {
    font-size:.69rem
  }
  .action-buttons .button {
    flex:1 1 45%;
    padding-inline:9px;
    font-size:.79rem
  }
  .feedback-option small {
    font-size:.7rem
  }
  .feedback-card h2 {
    font-size:1.27rem
  }
  .feedback-option strong {
    font-size:.8rem
  }
  .stat-card {
    padding:16px 10px
  }
  .stat-numbers span {
    font-size:.71rem
  }
}

@media(max-width:760px) {
  .workspace:has(#classroom-panel:not([hidden])) .teacher-content {
    order:1
  }
  .workspace:has(#classroom-panel:not([hidden])) .teacher-sidebar {
    order:2
  }
}

@media(prefers-reduced-motion:reduce) {
  *,*::before,*::after {
    scroll-behavior:auto!important;
    transition:none!important;
    animation:none!important
  }
}

@media print {
  .app-header,.app-footer,.teacher-sidebar,.controls-card,.notice,.page-heading,.room-heading-actions,.join-share {
    display:none!important
  }
  .teacher-main {
    padding:0
  }
  .workspace {
    display:block
  }
  .card {
    box-shadow:none;
    break-inside:avoid
  }
  .teacher-content {
    width:100%
  }
  #panel-summary {
    display:block!important
  }
  .review-tabs {
    display:none
  }
  .stats-grid {
    grid-template-columns:repeat(4,1fr)
  }
}

.feedback-option input {
  inset:0;
  width:100%;
  height:100%;
  z-index:1;
  cursor:inherit
}