:root {
  --ink: #123f49;
  --muted: #55727a;
  --sea: #08a9bd;
  --sea-deep: #07889b;
  --cream: #fff9e9;
  --sun: #ffd655;
  --coral: #ff7764;
  --shadow: 0 18px 55px rgba(19, 96, 108, .18);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: #eefbfa; font-family: "Noto Sans SC", system-ui, sans-serif; }
button, input, select { font: inherit; }
button { cursor: pointer; }
[hidden] { display: none !important; }
.modal-open { overflow: hidden; }
.eyebrow { margin: 0 0 8px; color: #088a9a; font-family: "Fredoka", sans-serif; font-weight: 700; letter-spacing: .17em; font-size: .78rem; }

.intro-splash { position: fixed; z-index: 100; inset: 0; display: grid; place-content: center; justify-items: center; overflow: hidden; background: radial-gradient(circle at 50% 42%, rgba(255,255,255,.96), rgba(255,240,248,.9) 32%, #dff8f5 74%); color: #314b59; transition: opacity .42s ease, transform .42s ease; }
.intro-splash.is-leaving { opacity: 0; transform: scale(1.035); pointer-events: none; }
.intro-splash > p { margin: 22px 0 5px; color: #e44f85; font-family: "Fredoka", sans-serif; font-size: .75rem; font-weight: 700; letter-spacing: .2em; animation: introRise .55s .34s both; }
.intro-splash > h1 { margin: 0; font-family: "Fredoka", sans-serif; font-size: clamp(2rem, 6vw, 4rem); letter-spacing: -.04em; animation: introRise .6s .43s both; }
.intro-compass { position: relative; display: grid; place-items: center; width: 116px; height: 116px; border: 3px solid rgba(255,255,255,.88); border-radius: 50%; background: linear-gradient(145deg, #fff, #ffe4ee); box-shadow: 0 18px 45px rgba(214,104,142,.18); animation: introPop .72s cubic-bezier(.2,.9,.25,1.25) both; }
.intro-compass span { font-size: 3.5rem; transform-origin: 50% 90%; animation: sailWave .9s .55s ease-in-out both; }
.intro-compass i { position: absolute; width: 12px; height: 12px; border-radius: 50%; background: #ff75a4; animation: orbitDot 1.1s ease-in-out infinite alternate; }
.intro-compass i:nth-of-type(1) { transform: translate(-65px,-12px); }
.intro-compass i:nth-of-type(2) { transform: translate(55px,-42px); background: #67cdbc; animation-delay: .16s; }
.intro-compass i:nth-of-type(3) { transform: translate(47px,53px); background: #ffd265; animation-delay: .3s; }
.intro-dot { position: absolute; width: 18px; height: 18px; border-radius: 50%; background: #ef76a2; opacity: .65; animation: introFloat 2.1s ease-in-out infinite alternate; }
.dot-one { left: 18%; top: 24%; width: 28px; height: 28px; }
.dot-two { right: 17%; top: 19%; background: #69cfc0; animation-delay: -.7s; }
.dot-three { right: 25%; bottom: 20%; width: 12px; height: 12px; background: #ffd05b; animation-delay: -1.2s; }
.intro-steps { display: flex; align-items: center; gap: 10px; margin-top: 24px; animation: introRise .6s .52s both; }
.intro-steps b { width: 10px; height: 10px; border-radius: 50%; background: #dce7e7; }
.intro-steps b:first-child { width: 34px; border-radius: 999px; background: #ee4f86; }

.topbar { position: sticky; z-index: 20; top: 0; display: flex; align-items: center; justify-content: space-between; padding: 10px clamp(18px, 5vw, 76px); background: rgba(245, 255, 251, .76); border-bottom: 1px solid rgba(255,255,255,.62); backdrop-filter: blur(20px); }
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; }
.brand-mark { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 50%; background: #d9f5f4; font-size: 1.5rem; }
.brand b, .brand small { display: block; }
.brand b { font-size: 1rem; }
.brand small { margin-top: 1px; color: var(--muted); font-family: "Fredoka"; font-size: .72rem; letter-spacing: .06em; }
.top-actions { display: flex; gap: 8px; }
.sound-pill, .teacher-link { border: 1px solid rgba(255,255,255,.78); border-radius: 999px; padding: 10px 15px; color: var(--ink); background: rgba(255,255,255,.48); box-shadow: 0 8px 22px rgba(17,93,107,.08); font-weight: 800; font-size: .82rem; }
.teacher-link { background: rgba(255,237,173,.66); }

.hero { position: relative; min-height: 620px; overflow: hidden; display: grid; align-items: end; padding: 72px clamp(20px, 7vw, 110px) 58px; background: #1ab6c8; isolation: isolate; }
.hero::after { content: ""; position: absolute; inset: 0; z-index: -1; background: linear-gradient(90deg, rgba(3, 78, 96, .9) 0%, rgba(3, 84, 100, .72) 38%, rgba(4, 80, 92, .14) 72%, rgba(4, 80, 92, .06)); }
.hero-art { position: absolute; z-index: -2; inset: 0; background: url("assets/adventure-archipelago.png") center / cover no-repeat; filter: saturate(.96); }
.hero-copy { max-width: 680px; color: white; }
.hero .eyebrow { color: #baf7ed; }
.hero h1 { max-width: 650px; margin: 0; font-size: clamp(3rem, 7vw, 6.4rem); line-height: .95; letter-spacing: -.05em; text-shadow: 0 5px 22px rgba(0,0,0,.16); }
.hero h1 span { display: block; color: var(--sun); }
.hero-lead { max-width: 570px; margin: 24px 0 30px; font-size: 1.08rem; line-height: 1.8; font-weight: 700; text-shadow: 0 2px 8px rgba(0,0,0,.15); }
.identity-strip { display: grid; grid-template-columns: 1.3fr .8fr auto; gap: 8px; padding: 8px; border: 1px solid rgba(255,255,255,.72); border-radius: 999px; background: rgba(255,255,255,.78); box-shadow: 0 18px 46px rgba(3,74,88,.2); backdrop-filter: blur(16px); color: var(--ink); }
.identity-strip label { padding: 0 10px; }
.identity-strip label + label { border-left: 1px dashed #b9dcda; }
.identity-strip label span { display: block; margin: 2px 0 -2px; color: #5f7d82; font-size: .7rem; font-weight: 900; }
.identity-strip input, .identity-strip select { width: 100%; min-height: 42px; border: 0; outline: 0; background: transparent; color: var(--ink); font-weight: 900; }
.primary-button, .secondary-button { border: 0; border-radius: 999px; padding: 15px 22px; background: var(--coral); color: white; font-weight: 900; box-shadow: 0 8px 18px rgba(255,119,100,.3); }
.primary-button span { margin-left: 10px; }
.identity-hint { min-height: 22px; margin: 11px 14px 0; color: rgba(255,255,255,.85); font-size: .75rem; font-weight: 700; }
.identity-hint.is-error { color: #fff1a7; }

.map-section { padding: 76px clamp(16px, 5vw, 72px) 110px; background: radial-gradient(ellipse at 10% 8%, rgba(255,246,205,.92) 0 5%, transparent 17%), radial-gradient(ellipse at 90% 32%, rgba(255,255,255,.5), transparent 19%), linear-gradient(180deg, #d9f6ef, #8adbd7 48%, #52c2ca); }
.section-heading { max-width: 1180px; margin: 0 auto 30px; display: flex; align-items: flex-end; justify-content: space-between; gap: 20px; }
.section-heading h2 { margin: 0; font-size: clamp(2rem, 4vw, 3.6rem); letter-spacing: -.05em; }
.legend { padding: 10px 14px; border-radius: 999px; background: rgba(255,255,255,.75); color: var(--muted); font-size: .78rem; font-weight: 800; }
.legend span { display: inline-block; width: 8px; height: 8px; margin-right: 7px; border-radius: 50%; background: #36b89b; }
.route-shell { position: relative; max-width: 1180px; margin: auto; overflow: hidden; padding: 35px 30px; background: radial-gradient(circle at 20% 20%, rgba(255,255,255,.34) 0 2px, transparent 3px); background-size: 44px 44px; }
.route-line { position: absolute; inset: 30px; width: calc(100% - 60px); height: calc(100% - 60px); pointer-events: none; }
.route-line path { fill: none; stroke: rgba(255,255,255,.9); stroke-width: 7; stroke-linecap: round; stroke-dasharray: 2 18; filter: drop-shadow(0 3px 0 rgba(7,136,155,.15)); }
.island-grid { position: relative; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 54px 36px; }
.island-node { transform: translateY(var(--bob)); position: relative; min-height: 190px; border: 0; background: transparent; color: var(--ink); text-align: center; transition: transform .22s ease; }
.island-node:hover, .island-node:focus-visible { transform: translateY(calc(var(--bob) - 8px)) scale(1.04); outline: none; }
.node-land { position: relative; display: grid; place-items: center; width: 124px; height: 92px; margin: 23px auto 10px; border-radius: 50% 48% 42% 50%; background: linear-gradient(#98e167 0 55%, #e6c272 56% 74%, #927456 75%); border: 6px solid rgba(255,255,255,.92); box-shadow: 0 14px 0 -4px rgba(11,113,131,.19), 0 20px 28px rgba(17,93,107,.18); }
.node-land::after { content: ""; position: absolute; width: 150%; height: 27px; left: -25%; bottom: -19px; border-radius: 50%; background: rgba(255,255,255,.42); }
.node-land i { position: relative; z-index: 1; font-size: 3.3rem; font-style: normal; filter: drop-shadow(0 4px 1px rgba(0,0,0,.08)); }
.node-land em { display: none; position: absolute; z-index: 3; right: -7px; top: -9px; width: 33px; height: 33px; place-items: center; border-radius: 50%; background: #20b678; color: white; border: 4px solid white; font-style: normal; }
.is-complete .node-land em { display: grid; }
.node-number { position: absolute; z-index: 2; left: calc(50% - 74px); top: 12px; display: grid; place-items: center; width: 42px; height: 42px; border-radius: 50%; background: var(--island); color: white; border: 4px solid white; font-family: "Fredoka"; font-weight: 700; box-shadow: 0 6px 12px rgba(0,0,0,.12); }
.island-node b, .island-node small { display: block; }
.island-node b { font-size: .96rem; }
.island-node small { color: var(--muted); font-family: "Fredoka"; font-size: .72rem; }

.overlay { position: fixed; z-index: 50; inset: 0; display: grid; place-items: center; padding: 18px; background: rgba(10,54,62,.65); backdrop-filter: blur(13px); }
.challenge, .result-sheet, .teacher-panel { width: min(1060px, 100%); max-height: calc(100vh - 24px); overflow-y: auto; overflow-x: hidden; border-radius: 44px; background: #fffdf7; box-shadow: 0 30px 90px rgba(0,0,0,.28); }
.challenge { position: relative; isolation: isolate; min-height: min(720px, calc(100vh - 24px)); padding: 22px clamp(18px, 5vw, 48px) 30px; background: #79dce5; }
.challenge::before { content: ""; position: absolute; z-index: -1; inset: 0; background: radial-gradient(circle at 9% 22%, rgba(255,255,255,.24) 0 12px, transparent 13px), radial-gradient(circle at 92% 31%, rgba(255,255,255,.2) 0 20px, transparent 21px), radial-gradient(circle at 12% 82%, rgba(255,255,255,.16) 0 8px, transparent 9px), radial-gradient(circle at 87% 78%, rgba(255,255,255,.18) 0 10px, transparent 11px); pointer-events: none; }
.challenge-top { display: grid; grid-template-columns: 52px 1fr 72px; align-items: center; gap: 15px; }
.back-button, .result-close { border: 0; width: 48px; height: 48px; border-radius: 50%; background: #e6f7f5; color: var(--ink); font-size: 1.7rem; }
.challenge-heading p { margin: 0; color: #168a98; font-family: "Fredoka"; font-size: .75rem; font-weight: 700; }
.challenge-heading h2 { margin: 2px 0 0; font-size: clamp(1.4rem, 4vw, 2rem); }
.challenge-heading { min-width: 0; }
.score-orb { display: grid; place-items: center; width: 68px; height: 68px; border-radius: 50%; background: #fff0ae; box-shadow: inset 0 0 0 5px white, 0 6px 16px rgba(0,0,0,.08); }
.score-orb small, .score-orb b { display: block; line-height: 1; }
.score-orb small { color: #80691c; font-size: .58rem; font-weight: 900; }
.score-orb b { margin-top: 3px; font-family: "Fredoka"; font-size: 1.45rem; }
.progress-track { height: 10px; margin: 18px 0 22px; overflow: hidden; border-radius: 999px; background: rgba(255,255,255,.62); }
.progress-track span { display: block; width: 0; height: 100%; background: linear-gradient(90deg, #29bba7, #ffd25c); transition: width .3s; }
.listen-stage { position: relative; display: grid; place-items: center; min-height: 210px; }
.listen-button { position: relative; z-index: 2; display: grid; place-items: center; width: 142px; height: 142px; border: 7px solid white; border-radius: 50%; background: #ff8b72; color: #5e332b; box-shadow: 0 9px 0 #d96655, 0 18px 30px rgba(31,104,115,.18); }
.listen-button:active { transform: scale(.96); }
.listen-button span { font-size: 2.8rem; }
.listen-button b { font-size: .92rem; }
.sound-ripple { position: absolute; width: 176px; height: 176px; border: 3px solid rgba(255,255,255,.34); border-radius: 50%; }
.ripple-two { width: 210px; height: 210px; }
.listen-button.is-speaking + .sound-ripple, .listen-button.is-speaking { animation: pulse 1s infinite; }
.question-instruction { width: max-content; max-width: 90%; margin: 0 auto 14px; padding: 9px 18px; border-radius: 999px; color: #225963; background: #fff; box-shadow: 0 5px 0 rgba(33,122,134,.14); text-align: center; font-weight: 900; }
.answers { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(16px, 4vw, 48px); padding: 5px 5% 8px; }
.answer-button { position: relative; place-self: center; width: min(100%, 210px); min-width: 0; aspect-ratio: 1; border: 8px solid #ffd45b; border-radius: 50%; background: #fff; box-shadow: 0 10px 0 #d9b43d, 0 16px 28px rgba(33,110,122,.18); transition: transform .18s, filter .18s; }
.answer-button:nth-child(2) { border-color: #ff8aa8; box-shadow: 0 10px 0 #d46683, 0 16px 28px rgba(33,110,122,.18); }
.answer-button:nth-child(3) { border-color: #5bbff3; box-shadow: 0 10px 0 #3597c9, 0 16px 28px rgba(33,110,122,.18); }
.answer-button:hover:not(:disabled) { transform: translateY(-9px) scale(1.08); filter: brightness(1.08); }
.answer-button span { font-size: clamp(4.8rem, 9vw, 7rem); filter: drop-shadow(0 5px 2px rgba(0,0,0,.12)); }
.answer-button.is-correct { border-color: #31bd79; background: #edfff5; box-shadow: 0 10px 0 #15945a; }
.answer-button.is-wrong { border-color: #f06f64; background: #fff0ed; box-shadow: 0 10px 0 #c84f46; }
.answer-button i { position: absolute; right: 13px; top: 13px; width: 30px; height: 30px; border-radius: 50%; }
.is-correct i::after { content: "✓"; color: #18a667; font-size: 1.5rem; font-style: normal; font-weight: 900; }
.is-wrong i::after { content: "×"; color: #e65d4c; font-size: 1.6rem; font-style: normal; font-weight: 900; }
.feedback { min-height: 75px; margin-top: 8px; }
.feedback:empty { display: grid; place-items: center; color: rgba(23,92,102,.72); font-size: .8rem; font-weight: 800; }
.feedback:empty::before { content: "选一张图，马上知道对不对"; }
.feedback-message { display: flex; align-items: center; gap: 12px; padding: 11px 14px; border: 3px solid white; border-radius: 999px; background: #e9fff4; box-shadow: 0 7px 0 rgba(33,122,134,.15); }
.feedback-message.wrong { background: #fff3df; }
.feedback-message > span { font-size: 2rem; }
.feedback-message div { flex: 1; }
.feedback-message b, .feedback-message small { display: block; }
.feedback-message small { color: var(--muted); }
.feedback-message button { border: 0; border-radius: 15px; padding: 13px 17px; background: #16a7b7; color: white; font-weight: 900; }
.auto-next-dots { display: flex; gap: 5px; padding: 8px; }
.auto-next-dots i { width: 7px; height: 7px; border-radius: 50%; background: #1aa899; animation: nextDot .62s ease-in-out infinite alternate; }
.auto-next-dots i:nth-child(2) { animation-delay: .13s; }
.auto-next-dots i:nth-child(3) { animation-delay: .26s; }

.result-sheet { position: relative; max-width: 620px; padding: 42px clamp(20px, 5vw, 58px); border: 7px solid rgba(255,255,255,.75); border-radius: 48% 52% 44% 56% / 42% 48% 52% 58%; background: radial-gradient(circle at 25% 12%, #fff9c9, transparent 22%), linear-gradient(150deg,#fffdf1,#dff9ee); text-align: center; }
.result-close { position: absolute; right: 20px; top: 20px; }
.result-burst { font-size: 5.4rem; }
.result-sheet h2 { margin: 0; font-size: clamp(2rem, 6vw, 3rem); }
.result-copy { color: var(--muted); line-height: 1.7; }
.result-score { display: flex; align-items: baseline; justify-content: center; gap: 7px; margin: 17px 0; }
.result-score span { color: var(--muted); font-weight: 700; }
.result-score strong { color: var(--sea-deep); font-family: "Fredoka"; font-size: 4.8rem; line-height: 1; }
.result-score small { font-weight: 900; }
.draw-zone { min-height: 170px; display: grid; place-items: center; }
.draw-button { border: 0; border-radius: 999px; padding: 18px 30px; background: linear-gradient(135deg, #ffd85b, #ff8f65); color: #593e13; font-weight: 900; box-shadow: 0 10px 0 #e77350; }
.reward-card { width: 280px; min-height: 160px; padding: 19px; display: grid; place-items: center; border-radius: 26px; background: radial-gradient(circle at 20% 20%, #fff7b3, transparent 18%), linear-gradient(135deg,#ffca4b,#ff7b70); color: white; border: 5px solid white; box-shadow: 0 15px 35px rgba(226,101,74,.3); transform: rotate(-2deg); }
.reward-card span, .reward-card small { font-family: "Fredoka"; letter-spacing: .12em; font-size: .67rem; }
.reward-card b { font-family: "Fredoka"; font-size: 4.4rem; line-height: .9; }
.reward-card strong { font-size: 1.1rem; }
.result-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 18px; }
.secondary-button { background: #e7f3f1; color: var(--ink); box-shadow: none; }
.primary-button:disabled { opacity: .45; cursor: not-allowed; }
.screenshot-tip { color: #789096; font-size: .75rem; }

.teacher-panel { max-width: 980px; padding: 34px; }
.teacher-head { display: flex; justify-content: space-between; gap: 20px; }
.teacher-head h2 { margin: 0; font-size: 2rem; }
.teacher-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 24px 0; }
.teacher-stats div { padding: 18px; border-radius: 22px; background: #eaf8f6; }
.teacher-stats span, .teacher-stats b { display: block; }
.teacher-stats span { color: var(--muted); font-size: .78rem; font-weight: 800; }
.teacher-stats b { margin-top: 4px; font-family: "Fredoka"; font-size: 2.2rem; }
.teacher-tools { display: flex; align-items: end; justify-content: space-between; gap: 15px; margin-bottom: 14px; }
.teacher-tools label { color: var(--muted); font-size: .75rem; font-weight: 800; }
.teacher-tools select { display: block; min-width: 150px; margin-top: 5px; padding: 10px; border: 2px solid #d5e9e6; border-radius: 12px; background: white; }
.danger-button { border: 0; border-radius: 12px; padding: 12px 16px; background: #fff0ed; color: #c34f42; font-weight: 900; }
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 14px 12px; border-bottom: 1px solid #e4efed; text-align: left; white-space: nowrap; }
th { color: var(--muted); font-size: .75rem; }
td strong { color: #ec6f4f; }
.empty-row { padding: 40px; color: #88a0a4; text-align: center; }
.teacher-note { color: #789096; font-size: .76rem; }
.teacher-login { position: relative; width: min(420px, calc(100% - 28px)); padding: 38px 34px 32px; border-radius: 34px; background: #fffdf7; text-align: center; box-shadow: 0 30px 90px rgba(0,0,0,.28); }
.teacher-login-icon { display: grid; place-items: center; width: 74px; height: 74px; margin: 0 auto 12px; border-radius: 50%; background: #e9f8f5; font-size: 2rem; }
.teacher-login h2 { margin: 4px 0 8px; font-size: 1.75rem; }
.teacher-login > p:not(.eyebrow) { margin: 0 0 22px; color: var(--muted); }
.teacher-login form { display: grid; gap: 10px; text-align: left; }
.teacher-login label { color: var(--muted); font-size: .78rem; font-weight: 800; }
.teacher-login input { width: 100%; padding: 14px 16px; border: 2px solid #cde5e2; border-radius: 16px; background: white; color: var(--ink); font: inherit; outline: none; }
.teacher-login input:focus { border-color: #18a9b4; box-shadow: 0 0 0 4px rgba(24,169,180,.12); }
.teacher-login .primary-button { justify-content: center; margin-top: 4px; }
.login-error { min-height: 20px; margin: 0; color: #d34f49; font-size: .78rem; font-weight: 800; }

@keyframes pulse { 50% { transform: scale(1.05); } }
@keyframes introPop { from { opacity: 0; transform: translateY(16px) scale(.65) rotate(-7deg); } to { opacity: 1; transform: translateY(0) scale(1) rotate(0); } }
@keyframes introRise { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
@keyframes introFloat { to { transform: translateY(-18px) scale(1.1); } }
@keyframes orbitDot { to { margin-top: -8px; } }
@keyframes sailWave { 40% { transform: rotate(-6deg); } 75% { transform: rotate(5deg); } }
@keyframes nextDot { to { transform: translateY(-5px); opacity: .42; } }

@media (max-width: 760px) {
  .topbar { padding: 10px 14px; }
  .brand > span:last-child { display: none; }
  .teacher-link, .sound-pill { display: block; padding: 9px 10px; font-size: .68rem; }
  .hero { min-height: 680px; align-items: end; padding: 52px 18px 30px; }
  .hero::after { background: linear-gradient(0deg, rgba(3,73,88,.95) 0%, rgba(3,73,88,.7) 54%, rgba(3,73,88,.08) 100%); }
  .hero-art { background-position: 62% center; }
  .hero h1 { font-size: 3.2rem; }
  .hero-lead { margin: 18px 0; font-size: .94rem; }
  .identity-strip { grid-template-columns: 1fr 1fr; border-radius: 22px; }
  .identity-strip .primary-button { grid-column: 1 / -1; }
  .section-heading { align-items: flex-start; flex-direction: column; }
  .route-shell { padding: 25px 8px; border-radius: 34px; }
  .route-line { display: none; }
  .island-grid { grid-template-columns: repeat(2, 1fr); gap: 36px 5px; }
  .island-node { min-height: 165px; transform: translateY(0); }
  .island-node:hover { transform: translateY(-5px); }
  .node-land { width: 106px; height: 78px; }
  .node-land i { font-size: 2.7rem; }
  .node-number { left: calc(50% - 62px); }
  .overlay { padding: 7px; }
  .challenge { min-height: 0; padding: 17px 10px 24px; border-radius: 25px; background: #79dce5; }
  .challenge-top { grid-template-columns: 42px minmax(0, 1fr) 54px; gap: 8px; }
  .back-button { width: 42px; height: 42px; }
  .score-orb { width: 52px; height: 52px; }
  .score-orb b { font-size: 1.15rem; }
  .challenge-heading h2 { font-size: 1.35rem; line-height: 1.15; }
  .listen-stage { min-height: 150px; }
  .listen-button { width: 118px; height: 118px; }
  .ripple-one { width: 150px; height: 150px; }
  .ripple-two { width: 174px; height: 174px; }
  .answers { gap: 9px; padding-inline: 3px; }
  .answer-button { width: 100%; min-height: 0; border-width: 6px; border-radius: 50%; box-shadow: 0 7px 0 #d9b43d, 0 12px 20px rgba(33,110,122,.14); }
  .answer-button:nth-child(2) { box-shadow: 0 7px 0 #d46683, 0 12px 20px rgba(33,110,122,.14); }
  .answer-button:nth-child(3) { box-shadow: 0 7px 0 #3597c9, 0 12px 20px rgba(33,110,122,.14); }
  .answer-button.is-correct { box-shadow: 0 7px 0 #15945a; }
  .answer-button.is-wrong { box-shadow: 0 7px 0 #c84f46; }
  .answer-button span { font-size: clamp(3.2rem, 14vw, 4.8rem); }
  .feedback-message { align-items: center; }
  .feedback-message > span { display: none; }
  .feedback-message button { padding: 11px; }
  .teacher-panel { padding: 22px 16px; border-radius: 28px; }
  .teacher-stats { grid-template-columns: 1fr 1fr 1fr; }
  .teacher-stats div { padding: 12px; }
  .teacher-stats b { font-size: 1.6rem; }
}

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