/* Layout: the tool fills the first screen (projector view); a plain reading column follows for teachers and search. Dark board look on purpose. */
:root{
  --board:#0f2a2e;
  --panel:#163940;
  --line:#2b5359;
  --chalk:#f4f1e3;
  --muted:#a6c0bc;
  --calm:#59d2b0;
  --near:#f4b942;
  --loud:#ff6a5c;
  --display:ui-rounded,"SF Pro Rounded","Arial Rounded MT Bold","Trebuchet MS",system-ui,sans-serif;
  --body:system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  color-scheme:dark;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--board);color:var(--chalk);font-family:var(--body);font-size:16px;line-height:1.55}
[hidden]{display:none!important}
a{color:var(--calm)}
a:focus-visible,button:focus-visible,summary:focus-visible,.chip input:focus-visible+span,select:focus-visible,input[type=range]:focus-visible{outline:3px solid var(--near);outline-offset:2px}

/* Tool */
.app{height:100vh;height:100svh;min-height:560px;max-height:1000px;max-width:1440px;margin:0 auto;display:grid;grid-template-rows:auto auto 1fr auto;gap:12px;padding-top:max(14px,env(safe-area-inset-top,0px));padding-bottom:14px;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px));background:var(--board)}
.app:fullscreen{max-width:none;max-height:none;height:100%}
.app:fullscreen .rail,.app:fullscreen .note{display:none}
header.top{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 16px}
.brand{display:flex;align-items:baseline;gap:10px;min-width:0}
.brand h1{font-family:var(--display);font-weight:800;font-size:clamp(24px,3vw,34px);margin:0;letter-spacing:.01em}
.brand span{color:var(--muted);font-size:14px}
.actions{display:flex;flex-wrap:wrap;gap:8px}
button,select{font:inherit;color:inherit}
.btn{display:inline-flex;align-items:center;gap:8px;border:1.5px solid var(--line);background:var(--panel);color:var(--chalk);border-radius:999px;padding:8px 14px;font-size:15px;font-weight:500;cursor:pointer;transition:border-color .15s}
.btn:hover{border-color:var(--muted)}
.btn.primary{background:var(--calm);border-color:var(--calm);color:var(--board);font-weight:600}
.btn.live{background:transparent;border-color:var(--calm);color:var(--calm)}
.dot{width:9px;height:9px;border-radius:50%;background:currentColor}
.btn.live .dot{animation:blink 1.4s infinite}
@keyframes blink{50%{opacity:.25}}
.rail{display:flex;flex-wrap:wrap;gap:10px 22px;align-items:center;background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:10px 14px}
.group{display:flex;flex-wrap:wrap;align-items:center;gap:6px;border:0;margin:0;padding:0;min-width:0}
.group legend{float:left;margin-right:6px;font-size:11px;text-transform:uppercase;letter-spacing:.09em;color:var(--muted);padding:0}
.chip{position:relative}
.chip input{position:absolute;opacity:0;inset:0;margin:0;cursor:pointer}
.chip span{display:inline-flex;align-items:center;gap:6px;border:1.5px solid var(--line);border-radius:10px;padding:5px 10px;font-size:14px;cursor:pointer;white-space:nowrap}
.chip b{font-family:var(--display);font-size:16px;line-height:1}
.chip input:checked+span{background:var(--chalk);color:var(--board);border-color:var(--chalk)}
.chip .tag{font-style:normal;font-size:10px;font-weight:600;text-transform:uppercase;letter-spacing:.08em;background:#ff9a3c;color:#1b1030;border-radius:6px;padding:1px 6px}
.setting{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--muted)}
.setting select{background:var(--board);border:1.5px solid var(--line);border-radius:8px;padding:4px 6px;color:var(--chalk)}
input[type=range]{accent-color:var(--calm);width:110px}
.stage{position:relative;min-height:240px;border-radius:22px;background:radial-gradient(120% 90% at 50% 0%,#1a4249 0%,var(--panel) 55%,#123237 100%);border:2px solid var(--line);overflow:hidden;transition:border-color .3s,box-shadow .3s}
.stage canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.stage.near{border-color:var(--near)}
.stage.alarm{border-color:var(--loud);box-shadow:0 0 0 4px rgba(255,106,92,.35) inset}
.status{position:absolute;top:14px;left:50%;transform:translateX(-50%);font-family:var(--display);font-weight:800;font-size:clamp(20px,3.2vw,40px);padding:6px 22px;border-radius:999px;background:rgba(15,42,46,.7);color:var(--calm);white-space:nowrap;pointer-events:none;transition:color .2s}
.stage.near .status{color:var(--near)}
.stage.alarm .status{color:var(--loud)}
.mic-info{position:absolute;left:12px;bottom:10px;font-size:11px;color:var(--muted);background:rgba(15,42,46,.7);border-radius:8px;padding:3px 8px;font-variant-numeric:tabular-nums;pointer-events:none}
.app:fullscreen .mic-info{display:none}
.demo{position:absolute;left:50%;bottom:12px;transform:translateX(-50%);display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:6px 12px;background:rgba(15,42,46,.82);border:1px dashed var(--line);border-radius:14px;padding:8px 14px;font-size:13px;color:var(--muted);width:min(600px,calc(100% - 24px))}
.demo input{width:min(220px,60vw)}
.link-btn{background:none;border:0;padding:0;color:var(--calm);text-decoration:underline;text-underline-offset:3px;cursor:pointer;font:inherit}
#micSelect{max-width:220px;text-overflow:ellipsis}
.manual{position:absolute;left:50%;bottom:12px;transform:translateX(-50%);display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:8px;background:rgba(15,42,46,.86);border:1px solid var(--line);border-radius:16px;padding:8px 12px;width:max-content;max-width:calc(100% - 24px)}
.manual .m-label{font-size:11px;text-transform:uppercase;letter-spacing:.09em;color:var(--muted);margin-right:4px}
.manual [data-m]{font:inherit;font-size:15px;font-weight:600;border-radius:12px;padding:8px 14px;cursor:pointer;border:2px solid var(--line);background:var(--panel);color:var(--chalk)}
.manual [data-m] kbd{font:inherit;font-size:11px;opacity:.65;margin-left:4px}
.manual [data-m="quiet"][aria-pressed="true"]{background:var(--calm);border-color:var(--calm);color:var(--board)}
.manual [data-m="near"][aria-pressed="true"]{background:var(--near);border-color:var(--near);color:var(--board)}
.manual [data-m="loud"][aria-pressed="true"]{background:var(--loud);border-color:var(--loud);color:var(--board)}
.manual button:focus-visible,.link-btn:focus-visible{outline:3px solid var(--near);outline-offset:2px}
.strip{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:8px 20px;align-items:center}
.quiet{display:grid;gap:6px;min-width:0}
.quiet .row{display:flex;justify-content:space-between;gap:12px;font-size:13px;color:var(--muted)}
.quiet .row strong{color:var(--chalk);font-weight:600;font-variant-numeric:tabular-nums}
.bar{height:14px;border-radius:999px;background:var(--panel);border:1px solid var(--line);overflow:hidden}
.bar i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--calm),#9be8d2);border-radius:999px}
.stars{display:flex;align-items:center;gap:10px}
.stars .count{font-family:var(--display);font-weight:800;font-size:32px;color:var(--near);font-variant-numeric:tabular-nums;min-width:2ch;text-align:right}
.stars .star{font-size:28px;color:var(--near);display:inline-block}
.stars .star.pop{animation:pop .7s ease-out}
@keyframes pop{0%{transform:scale(1)}40%{transform:scale(1.6) rotate(-12deg)}100%{transform:scale(1)}}
.stars .btn{padding:5px 10px;font-size:12px}
.note{grid-column:1/-1;font-size:12px;color:var(--muted);margin:0}
.notice{grid-column:1/-1;font-size:13px;color:var(--near);margin:0}
.scroll-hint{grid-column:1/-1;font-size:12px;color:var(--muted);margin:0}

/* Reading column */
.content{max-width:720px;margin:0 auto;padding-block:56px 40px;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px));display:grid;gap:44px}
.content section{display:grid;gap:12px}
.content h2{font-family:var(--display);font-weight:800;font-size:clamp(24px,3.4vw,30px);line-height:1.2;margin:0;text-wrap:balance}
.content p,.content ol{margin:0;color:#dfe8e4}
.content ol{padding-left:1.3em;display:grid;gap:6px}
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:14px}
table{border-collapse:collapse;width:100%;min-width:520px;font-size:15px}
th,td{text-align:left;padding:10px 14px;border-bottom:1px solid var(--line);vertical-align:top}
tr:last-child td{border-bottom:0}
th{font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted);font-weight:600;background:var(--panel)}
td.lv{font-family:var(--display);font-weight:800;font-size:20px;color:var(--calm);white-space:nowrap}
details{border:1px solid var(--line);border-radius:12px;background:var(--panel)}
summary{cursor:pointer;padding:12px 16px;font-weight:600;list-style:none}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";float:right;color:var(--muted);font-weight:400}
details[open] summary::after{content:"–"}
details p{padding:0 16px 14px}
.faq{display:grid;gap:8px}
footer.site{border-top:1px solid var(--line);padding-block:24px 32px;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px));font-size:13px;color:var(--muted)}
footer.site .in{max-width:720px;margin:0 auto;display:flex;flex-wrap:wrap;gap:8px 18px;justify-content:space-between}
footer.site nav{display:flex;gap:16px;flex-wrap:wrap}

@media (max-width:640px){
  .app{height:auto;min-height:0;max-height:none}
  .stage{min-height:440px}
  .demo{font-size:12px;padding:6px 10px}
  .strip{grid-template-columns:1fr}
  .stars{justify-content:space-between}
  .brand span{display:none}
}
@media (prefers-reduced-motion:reduce){
  .btn.live .dot,.stars .star.pop{animation:none}
}

/* Timer: a card in the stage's top-left corner; presets live in the rail */
.tchip{font:inherit;font-size:14px;border:1.5px solid var(--line);background:transparent;color:var(--chalk);border-radius:10px;padding:5px 10px;cursor:pointer;white-space:nowrap}
.tchip[aria-pressed="true"]{background:var(--chalk);color:var(--board);border-color:var(--chalk)}
.check{display:inline-flex;align-items:center;gap:6px;font-size:14px;color:var(--chalk);margin-left:6px;cursor:pointer;white-space:nowrap}
.check input{accent-color:var(--near);width:16px;height:16px}
.tchip:focus-visible,.check input:focus-visible,.t-btn:focus-visible,.t-x:focus-visible{outline:3px solid var(--near);outline-offset:2px}
.timer{position:absolute;top:14px;left:14px;z-index:2;display:grid;gap:8px;min-width:210px;background:rgba(15,42,46,.86);border:1.5px solid var(--line);border-radius:18px;padding:12px 14px}
.t-time{font-family:var(--display);font-weight:800;font-size:clamp(40px,5.4vw,72px);line-height:1;font-variant-numeric:tabular-nums;color:var(--chalk);letter-spacing:.01em}
.timer.running .t-time{color:var(--calm)}
.timer.low .t-time{color:var(--near)}
.timer.done .t-time{color:var(--near);animation:tflash .8s 4}
@keyframes tflash{50%{opacity:.25}}
.t-bar{height:8px;border-radius:999px;background:var(--panel);overflow:hidden}
.t-bar i{display:block;height:100%;width:100%;background:var(--calm);border-radius:999px}
.timer.low .t-bar i,.timer.done .t-bar i{background:var(--near)}
.t-chal{font-size:12px;color:var(--muted);letter-spacing:.06em;text-transform:uppercase;display:flex;align-items:center;gap:8px}
.t-lives{font-size:18px;letter-spacing:.2em;color:var(--near)}
.t-row{display:flex;flex-wrap:wrap;gap:6px;align-items:center}
.t-btn{font:inherit;font-size:14px;font-weight:600;border:1.5px solid var(--line);background:var(--panel);color:var(--chalk);border-radius:10px;padding:6px 10px;cursor:pointer}
.t-btn.go{background:var(--calm);border-color:var(--calm);color:var(--board);min-width:72px}
.t-x{margin-left:auto;font:inherit;font-size:20px;line-height:1;border:0;background:none;color:var(--muted);cursor:pointer;padding:2px 6px}
.stage.has-timer .status{left:auto;right:14px;transform:none}
.app:fullscreen .t-row .t-btn:not(.go),.app:fullscreen .t-x{display:none}
.app:fullscreen .timer{transform-origin:top left;transform:scale(1.25)}
.big-timer .t-time{font-size:clamp(56px,8vw,110px)}
@media (max-width:640px){
  .timer{left:10px;right:10px;top:64px;min-width:0}
  .stage.has-timer .status{left:50%;right:auto;transform:translateX(-50%)}
}
@media (prefers-reduced-motion:reduce){.timer.done .t-time{animation:none}}