/* ==========================================================================
   Student cabinet + teacher admin. Same ink-on-paper system as the landing,
   but denser: this is a working surface, not a page you read once.
   ========================================================================== */

body.app{background:var(--paper-2);font-size:16px}

/* ---------------------------------------------------------------- shell --- */
.shell{display:grid;grid-template-columns:246px minmax(0,1fr);min-height:100vh}
@media (max-width:900px){.shell{grid-template-columns:1fr}}

.side{
  background:var(--white);
  border-right:1px solid var(--line);
  padding:22px 18px;
  display:flex;flex-direction:column;gap:22px;
  position:sticky;top:0;height:100vh;overflow-y:auto;
}
@media (max-width:900px){
  .side{position:static;height:auto;border-right:0;border-bottom:1px solid var(--line);
        flex-direction:row;align-items:center;gap:14px;overflow-x:auto;padding:12px 14px}
  .side .side-foot{margin-left:auto}
  .side-nav{flex-direction:row;gap:4px}
}

.side-brand{display:flex;align-items:baseline;gap:.45em;font-family:var(--display);font-size:1.2rem;color:var(--ink);white-space:nowrap}
.side-brand small{font-family:var(--sans);font-size:.6rem;font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--ink-3)}

.side-nav{display:flex;flex-direction:column;gap:2px}
.side-nav a,.side-nav button{
  display:flex;align-items:center;gap:10px;
  padding:.62em .78em;border-radius:9px;border:0;background:transparent;
  font-size:.93rem;color:var(--ink-2);cursor:pointer;text-align:left;white-space:nowrap;
  transition:background .2s,color .2s;
}
.side-nav a:hover,.side-nav button:hover{background:var(--paper-2);color:var(--ink)}
.side-nav .on{background:var(--mark-soft);color:var(--mark-deep);font-weight:500}
.side-nav svg{width:17px;height:17px;flex:none}
.side-nav .badge{
  margin-left:auto;background:var(--live);color:#fff;border-radius:999px;
  font-size:.68rem;font-weight:600;padding:.1em .45em;min-width:18px;text-align:center;
}
.side-foot{margin-top:auto;padding-top:16px;border-top:1px solid var(--line);font-size:.85rem;color:var(--ink-3)}

.main{padding:clamp(18px,3vw,34px);max-width:1180px;width:100%}
.page-head{margin-bottom:24px}
.page-head h1{font-size:clamp(1.8rem,3.4vw,2.5rem);margin-bottom:6px}
.page-head p{color:var(--ink-3);margin:0;font-size:.96rem}

.view{display:none}
.view.on{display:block;animation:fade .3s var(--ease)}
@keyframes fade{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
@media (prefers-reduced-motion:reduce){.view.on{animation:none}}

/* ---------------------------------------------------------------- stats --- */
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px;margin-bottom:24px}
.stat{background:var(--white);border:1px solid var(--line);border-radius:12px;padding:16px 18px}
.stat .k{font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--ink-3);margin-bottom:6px}
.stat .v{font-family:var(--display);font-size:2rem;line-height:1;color:var(--ink)}
.stat .v small{font-family:var(--sans);font-size:.9rem;color:var(--ink-3);margin-left:3px}
.stat--sun .v{color:#b57310}
.stat--live .v{color:var(--live)}
.stat--tick .v{color:var(--tick)}

/* ---------------------------------------------------------------- panels -- */
.panel{background:var(--white);border:1px solid var(--line);border-radius:14px;padding:20px;margin-bottom:18px}
.panel-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:16px;flex-wrap:wrap}
.panel-head h2{font-size:1.4rem}
.panel-head h3{font-size:1.15rem}

.list{display:flex;flex-direction:column}
.item{
  display:flex;align-items:center;gap:13px;
  padding:13px 2px;border-bottom:1px solid var(--line);
}
.item:last-child{border-bottom:0}
.item .t{font-weight:500;color:var(--ink);font-size:.97rem}
.item .s{font-size:.85rem;color:var(--ink-3)}
.item.clickable{cursor:pointer;border-radius:9px;padding-left:10px;padding-right:10px;transition:background .2s}
.item.clickable:hover{background:var(--paper-2)}

.avatar{
  width:38px;height:38px;border-radius:50%;flex:none;
  background:var(--mark-soft);color:var(--mark-deep);
  display:grid;place-items:center;font-weight:600;font-size:.9rem;
  overflow:hidden;
}
.avatar img{width:100%;height:100%;object-fit:cover}
.avatar--lg{width:56px;height:56px;font-size:1.2rem}

/* ---------------------------------------------------------------- lessons - */
.lesson{
  display:flex;align-items:flex-start;gap:12px;
  padding:13px;border:1px solid var(--line);border-radius:11px;margin-bottom:9px;
  background:var(--white);transition:border-color .25s,transform .25s var(--ease);
}
.lesson:hover{border-color:var(--line-strong);transform:translateX(2px)}
.lesson.done{background:var(--paper);border-color:transparent}
.lesson.done .lt{color:var(--ink-3);text-decoration:line-through;text-decoration-color:var(--tick);text-decoration-thickness:1.5px}
.tickbox{
  width:24px;height:24px;border-radius:7px;flex:none;margin-top:1px;
  border:1.5px solid var(--line-strong);background:var(--white);
  display:grid;place-items:center;cursor:pointer;color:transparent;
  transition:background .2s,border-color .2s,color .2s;
}
.tickbox:hover{border-color:var(--tick)}
.tickbox.on{background:var(--tick);border-color:var(--tick);color:#fff}
.tickbox svg{width:14px;height:14px}
.lt{font-weight:500;color:var(--ink);font-size:.98rem;display:block;margin-bottom:2px}
.ls{font-size:.87rem;color:var(--ink-3);margin:0}

.progress{height:6px;border-radius:99px;background:var(--paper-3);overflow:hidden}
.progress i{display:block;height:100%;background:var(--mark);border-radius:99px;transition:width .6s var(--ease)}
.progress.tick i{background:var(--tick)}

/* ---------------------------------------------------------------- badges -- */
.badges{display:grid;grid-template-columns:repeat(auto-fill,minmax(104px,1fr));gap:11px}
.badge-t{
  text-align:center;padding:15px 8px;border-radius:12px;
  border:1px solid var(--line);background:var(--white);
}
.badge-t .ic{
  width:40px;height:40px;margin:0 auto 8px;border-radius:50%;
  background:var(--sun-soft);color:#b57310;display:grid;place-items:center;
}
.badge-t .ic svg{width:19px;height:19px}
.badge-t b{display:block;font-size:.82rem;color:var(--ink);font-weight:600;line-height:1.25}
.badge-t small{display:block;font-size:.72rem;color:var(--ink-3);margin-top:3px;line-height:1.3}
.badge-t.locked{opacity:.45;filter:grayscale(1)}

/* ---------------------------------------------------------------- homework */
.hw{border:1px solid var(--line);border-radius:12px;padding:16px;margin-bottom:11px;background:var(--white)}
.hw.pending{border-color:var(--sun);background:linear-gradient(180deg,var(--white),var(--sun-soft))}
.hw.reviewed{border-color:var(--tick-soft)}
.hw h4{font-family:var(--sans);font-size:1rem;font-weight:600;color:var(--ink);margin:0 0 5px}
.hw .brief{font-size:.9rem;color:var(--ink-2);margin:0 0 10px}
.hw .fb{
  margin-top:11px;padding:12px 14px;border-radius:10px;
  background:var(--mark-soft);border-left:3px solid var(--mark);
}
.hw .fb .who{font-size:.7rem;letter-spacing:.1em;text-transform:uppercase;color:var(--mark);font-weight:600;margin-bottom:4px}
.hw .fb p{margin:0;font-size:.92rem;color:var(--ink-2)}
.hw .sub{background:var(--paper);border-radius:9px;padding:11px 13px;font-size:.92rem;color:var(--ink-2);white-space:pre-wrap;margin:9px 0 0}

/* ---------------------------------------------------------------- tables -- */
.tbl{width:100%;border-collapse:collapse;font-size:.92rem}
.tbl th{
  text-align:left;font-size:.7rem;letter-spacing:.1em;text-transform:uppercase;
  color:var(--ink-3);font-weight:600;padding:0 10px 9px;border-bottom:1px solid var(--line);
}
.tbl td{padding:11px 10px;border-bottom:1px solid var(--line);color:var(--ink-2);vertical-align:middle}
.tbl tr:last-child td{border-bottom:0}
.tbl tr.clickable{cursor:pointer}
.tbl tr.clickable:hover td{background:var(--paper-2)}
.tbl td b{color:var(--ink);font-weight:600}
.tbl-wrap{overflow-x:auto;margin:0 -6px;padding:0 6px}

/* ---------------------------------------------------------------- modal --- */
.modal{
  position:fixed;inset:0;z-index:120;display:none;
  align-items:center;justify-content:center;padding:18px;
  background:rgba(22,32,46,.45);backdrop-filter:blur(3px);
}
.modal.on{display:flex}
.modal-box{
  background:var(--white);border-radius:16px;width:100%;max-width:560px;
  max-height:88vh;overflow-y:auto;padding:24px;box-shadow:var(--shadow-md);
  animation:pop .28s var(--ease);
}
.modal-box.wide{max-width:840px}
@keyframes pop{from{opacity:0;transform:translateY(12px) scale(.985)}to{opacity:1;transform:none}}
@media (prefers-reduced-motion:reduce){.modal-box{animation:none}}
.modal-head{display:flex;align-items:flex-start;justify-content:space-between;gap:14px;margin-bottom:18px}
.modal-head h3{font-size:1.5rem}
.x{border:0;background:transparent;font-size:1.5rem;line-height:1;color:var(--ink-3);cursor:pointer;padding:2px 6px;border-radius:7px}
.x:hover{background:var(--paper-2);color:var(--ink)}

/* ---------------------------------------------------------------- tabs ---- */
.tabs{display:flex;gap:3px;background:var(--paper-3);padding:3px;border-radius:10px;margin-bottom:18px;overflow-x:auto}
.tabs button{
  border:0;background:transparent;cursor:pointer;white-space:nowrap;
  font-size:.88rem;color:var(--ink-3);padding:.5em .9em;border-radius:8px;
  transition:background .2s,color .2s;
}
.tabs button.on{background:var(--white);color:var(--mark);font-weight:500;box-shadow:var(--shadow-sm)}

/* ---------------------------------------------------------------- studio -- */
/* Going live: the camera preview is the whole interface. */
.studio{display:grid;grid-template-columns:minmax(0,1.7fr) minmax(0,1fr);gap:16px}
@media (max-width:940px){.studio{grid-template-columns:1fr}}
.stage{
  background:var(--ink);border-radius:14px;overflow:hidden;position:relative;
  aspect-ratio:16/9;display:grid;place-items:center;
}
.stage video{width:100%;height:100%;object-fit:cover;background:#000}
.stage .placeholder{color:rgba(255,255,255,.5);font-size:.94rem;text-align:center;padding:20px}
.stage .onair{
  position:absolute;top:12px;left:12px;z-index:3;
  display:flex;align-items:center;gap:7px;
  background:var(--live);color:#fff;border-radius:999px;
  padding:.34em .8em;font-size:.76rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase;
}
.stage .count{
  position:absolute;top:12px;right:12px;z-index:3;
  background:rgba(0,0,0,.6);color:#fff;border-radius:999px;
  padding:.34em .8em;font-size:.8rem;backdrop-filter:blur(6px);
}
.studio-controls{display:flex;gap:9px;flex-wrap:wrap;margin-top:12px}

.chat{display:flex;flex-direction:column;height:100%;min-height:320px;background:var(--white);border:1px solid var(--line);border-radius:14px;overflow:hidden}
.chat-log{flex:1;overflow-y:auto;padding:14px;display:flex;flex-direction:column;gap:11px}
.chat-msg .n{font-size:.76rem;font-weight:600;color:var(--mark);margin-bottom:2px}
.chat-msg.teacher .n{color:var(--live)}
.chat-msg p{margin:0;font-size:.92rem;color:var(--ink-2);line-height:1.45}
.chat-form{display:flex;gap:8px;padding:11px;border-top:1px solid var(--line)}
.chat-form input{flex:1}
.chat-empty{color:var(--ink-4);font-size:.9rem;text-align:center;margin:auto;padding:20px}

/* ---------------------------------------------------------------- login --- */
.login-page{
  min-height:100vh;display:grid;place-items:center;padding:24px;
  background:
    radial-gradient(60% 50% at 78% 12%, rgba(43,78,230,.08), transparent 62%),
    radial-gradient(50% 44% at 10% 90%, rgba(14,158,147,.07), transparent 60%),
    var(--paper);
}
.login-box{width:100%;max-width:400px}
.login-card{background:var(--white);border:1px solid var(--line);border-radius:16px;padding:28px;box-shadow:var(--shadow-md)}

/* ---------------------------------------------------------------- misc ---- */
.empty{
  text-align:center;padding:34px 20px;color:var(--ink-3);
  border:1px dashed var(--line-strong);border-radius:12px;font-size:.94rem;
}
.empty b{display:block;color:var(--ink);font-weight:600;margin-bottom:5px;font-size:1rem}
.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
@media (max-width:700px){.grid-2{grid-template-columns:1fr}}
.grid-3{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:14px}

.spark{display:flex;align-items:flex-end;gap:3px;height:46px}
.spark i{flex:1;background:var(--mark-soft);border-radius:3px 3px 0 0;min-height:2px;transition:background .2s}
.spark i.hot{background:var(--mark)}

.copyfield{
  display:flex;gap:8px;align-items:center;background:var(--paper);
  border:1px solid var(--line);border-radius:9px;padding:8px 11px;font-size:.9rem;
}
.copyfield code{flex:1;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--ink);overflow-x:auto;white-space:nowrap}