/* Оболочка Mois.Air. Без внешних библиотек интерфейса. */
:root{
  --g900:#053626;--g800:#075138;--g700:#0a6b4a;--g600:#0f8a5f;--g500:#16a874;--g400:#35c790;
  --g200:#b9edd6;--g100:#e2f7ee;--g50:#f2fbf7;
  --ink:#0c1a14;--muted:#5c7a6c;--line:#cfe9dd;
  font-family:"Segoe UI Variable Display","Segoe UI",system-ui,-apple-system,Roboto,Arial,sans-serif;
  color:var(--ink);background:var(--g900);font-synthesis:none;
}
*{box-sizing:border-box}
body{margin:0}
button,input{font:inherit;color:inherit}
h1,h2{letter-spacing:-.4px;line-height:1.15}

/* ---------- базовые элементы ---------- */
.btn{border:0;background:linear-gradient(160deg,var(--g500),var(--g700));color:#fff;font-weight:600;font-size:17px;
  padding:13px 22px;border-radius:12px;cursor:pointer;box-shadow:0 6px 18px rgba(7,81,56,.28);transition:filter .15s}
.btn:hover:not(:disabled){filter:brightness(1.07)}
.btn:disabled{opacity:.5;cursor:default;box-shadow:none}
.btn.ghost{background:#fff;color:var(--g700);border:1px solid var(--line);box-shadow:none}
.btn.ghost:hover:not(:disabled){background:var(--g50)}
.btn.block{display:block;width:100%}
.btn+.btn{margin-top:8px}
.field{display:block;width:100%;padding:13px 16px;border:1px solid var(--line);border-radius:12px;background:#fff;
  font-size:17px;margin-bottom:12px}
.field:focus{outline:0;border-color:var(--g400);box-shadow:0 0 0 3px rgba(22,168,116,.18)}
.field.code{text-align:center;letter-spacing:6px;font-size:26px;font-weight:700;text-transform:uppercase}
.field.code::placeholder{letter-spacing:4px;font-weight:400;color:#a9c4b5}
.link-button{background:none;border:0;padding:6px 10px;color:var(--g700);font-size:15px;cursor:pointer;border-radius:8px}
.link-button:hover{background:var(--g100)}
.muted{color:var(--muted);font-size:14px;margin:12px 0 0}
.checkbox{display:flex;gap:10px;align-items:center;font-size:16px;cursor:pointer;margin-top:10px}
.checkbox input{width:18px;height:18px;accent-color:var(--g600)}
.spinner{width:44px;height:44px;border:4px solid var(--g200);border-top-color:var(--g600);border-radius:50%;
  animation:spin .9s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.loading{min-height:100dvh;display:grid;place-items:center;background:var(--g50)}
.notice{display:flex;gap:10px;align-items:flex-start;margin-top:14px;padding:12px 14px;border-radius:12px;
  background:#fdecea;border:1px solid #f0b8b0;color:#8a2b1f;font-size:15px;text-align:left}
.notice-close{background:none;border:0;font-size:20px;line-height:1;cursor:pointer;color:inherit;margin-left:auto}

/* ---------- вход ---------- */
/* Фон входа — градиент в фирменных зелёных, без картинки и без надписей:
   не грузится вовсе и не перерисовывается при прокрутке на телефоне. */
.entry-scene{min-height:100dvh;display:grid;place-items:center;padding:32px 20px;
  background:
    radial-gradient(90% 70% at 18% 0%,rgba(22,168,116,.55),transparent 60%),
    radial-gradient(70% 60% at 100% 100%,rgba(15,138,95,.45),transparent 62%),
    linear-gradient(150deg,var(--g900) 0%,var(--g800) 48%,#04281c 100%)}
.entry-card{background:rgba(255,255,255,.94);backdrop-filter:blur(18px);border:1px solid rgba(255,255,255,.6);
  border-radius:26px;padding:clamp(28px,4vw,44px);width:min(100%,440px);box-shadow:0 28px 80px rgba(0,43,41,.4);
  text-align:center}
.entry-logo{width:76px;height:76px;border-radius:22px;margin:0 auto 20px;display:block}
.entry-card h1{font-size:28px;margin:0 0 14px}
.entry-card p{font-size:16px;line-height:1.5;color:var(--muted);margin:0 0 22px}

/* ---------- сцена преподавателя ---------- */
.teacher-scene{min-height:100dvh;padding:18px;
  background:radial-gradient(ellipse at 92% 0,rgba(22,178,100,.42),transparent 52%),
             linear-gradient(125deg,#033f31,#075738 50%,#063c2c)}

/* выбор лекции */
.picker-scene{display:grid;place-items:center}
.picker{width:min(100%,720px);background:#fff;border-radius:26px;padding:clamp(26px,4vw,40px);
  box-shadow:0 26px 70px rgba(0,40,30,.45);text-align:center}
.picker-logo{width:70px;border-radius:20px;margin:0 auto 18px;display:block}
.picker h1{font-size:27px;margin:0 0 22px;color:var(--g800)}
.lecture-list{display:grid;gap:12px}
.lecture-card{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:16px;text-align:left;
  padding:18px 20px;border:1px solid var(--line);border-radius:16px;background:var(--g50);cursor:pointer;
  transition:border-color .15s,transform .15s,box-shadow .15s}
.lecture-card:hover:not(:disabled){border-color:var(--g400);transform:translateY(-1px);box-shadow:0 10px 26px rgba(7,81,56,.14)}
.lecture-card:disabled{opacity:.6;cursor:default}
.lecture-number{width:44px;height:44px;border-radius:12px;display:grid;place-items:center;font-size:19px;font-weight:700;
  color:#fff;background:linear-gradient(160deg,var(--g500),var(--g700))}
.lecture-title{font-size:18px;font-weight:600;color:var(--g800);line-height:1.3}
.lecture-go{font-size:15px;color:var(--g600);font-weight:600;white-space:nowrap}
.picker-foot{display:flex;justify-content:center;gap:6px;margin-top:22px}
.history{margin-top:14px;display:flex;flex-direction:column;gap:4px;font-size:13px;color:var(--muted)}

/* эфир */
.teacher-layout{display:grid;grid-template-columns:minmax(0,1fr) 312px;gap:16px;align-items:start;
  max-width:1920px;margin:0 auto}
.presentation-pane{min-width:0;border-radius:18px;overflow:hidden;background:#fff;border:1px solid rgba(255,255,255,.35);
  box-shadow:0 14px 44px rgba(0,40,36,.42)}
.presentation-pane iframe{display:block;width:100%;height:calc(100dvh - 36px);min-height:540px;border:0}
.invite-panel{background:#fff;border-radius:18px;padding:20px 18px;text-align:center;display:flex;flex-direction:column;
  gap:12px;box-shadow:0 14px 44px rgba(0,40,36,.42)}
.qr{display:block;width:100%;height:auto;max-width:248px;margin:0 auto;border-radius:10px}
.invite-panel h2{font-size:19px;font-weight:600;margin:0;color:var(--g800)}
.invite-code{font-size:32px;font-weight:800;letter-spacing:5px;line-height:1;color:var(--g800);
  background:var(--g50);border:1px dashed var(--g200);border-radius:12px;padding:12px 6px}
.audience-count{font-size:13px;color:var(--muted);margin:0}
.slide-controls{display:flex;align-items:center;justify-content:space-between;gap:10px;
  border-top:1px solid var(--line);padding-top:14px}
.nav{flex:1;border:0;background:linear-gradient(160deg,var(--g500),var(--g700));color:#fff;font-size:22px;font-weight:700;
  height:52px;border-radius:14px;cursor:pointer;box-shadow:0 6px 18px rgba(7,81,56,.3)}
.nav:hover:not(:disabled){filter:brightness(1.08)}
.nav:disabled{opacity:.45;cursor:default;box-shadow:none}
.slide-counter{font-size:15px;font-weight:700;color:var(--g700);font-variant-numeric:tabular-nums;min-width:62px}
.slide-name{font-size:13px;color:var(--muted);margin:-4px 0 0;line-height:1.35}
/* Свободная навигация: галочка живёт рядом с управлением слайдами. */
.checkbox.roam{justify-content:center;margin-top:12px;font-size:15px;font-weight:600;color:var(--g800)}
.roam-note{margin-top:4px;font-size:12px;text-align:center;line-height:1.35}
.question-list{border-top:1px solid var(--line);padding-top:12px;text-align:left}
.question-list h3{margin:0 0 8px;font-size:14px;font-weight:700;color:var(--g700);
  text-transform:uppercase;letter-spacing:.8px}
.question-row{display:flex;align-items:center;gap:8px;margin-bottom:6px}
.question-num{width:22px;height:22px;flex:0 0 22px;border-radius:50%;background:var(--g100);color:var(--g700);
  font-size:12px;font-weight:700;display:grid;place-items:center}
.question-label{flex:1;min-width:0;font-size:13px;color:var(--muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.question-count{font-size:15px;font-weight:700;color:var(--g800);font-variant-numeric:tabular-nums}
.question-list .muted{margin-top:4px;font-size:12px}
.finish{margin-top:auto;color:var(--muted)}
.waiting-panel{min-height:540px;display:flex;flex-direction:column;justify-content:center;align-items:center;
  text-align:center;padding:40px;color:var(--g800)}

/* ---------- студент ---------- */
.student-scene{min-height:100dvh;background:var(--g50);display:grid;place-items:center}
.student-scene>iframe{display:block;width:100%;height:100dvh;border:0}
.connection-note{position:fixed;bottom:18px;left:50%;transform:translateX(-50%);padding:12px 18px;border-radius:12px;
  background:#fff7df;box-shadow:0 3px 22px rgba(41,70,38,.18);font-size:15px}

/* ---------- диалог ---------- */
.backdrop{position:fixed;inset:0;background:rgba(4,21,15,.55);display:grid;place-items:center;padding:20px;z-index:50}
.dialog{background:#fff;border-radius:20px;padding:26px;width:min(100%,440px);box-shadow:0 30px 80px rgba(0,0,0,.4)}
.dialog h2{margin:0 0 12px;font-size:22px;color:var(--g800)}
.dialog p{font-size:16px;color:var(--muted);margin:0}
.dialog-actions{display:flex;gap:10px;justify-content:flex-end;margin-top:22px}
.dialog-actions .btn+.btn{margin-top:0}

@media (max-width:980px){
  .teacher-layout{grid-template-columns:1fr}
  .presentation-pane iframe{height:64dvh;min-height:380px}
  .invite-panel{max-width:420px;width:100%;margin:0 auto}
  .qr{max-width:200px}
}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}