:root{
  --ink:#14202C; --ink-2:#1B2B3A; --blue:#0079A6; --sky:#38B6E8; --sky-bg:#E6F4FA;
  --paper:#EEF1F4; --card:#fff; --steel:#5A6473; --line:#D8DCE6; --soft:#F6F8FA;
  --ok:#127A4B; --ok-bg:#E7F3ED; --mid:#9A5B00; --mid-bg:#FFF4DC; --bad:#C62828; --bad-bg:#FBE9E9;
  --body:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
  --display:'Poppins',var(--body);
  --mono:'IBM Plex Mono',ui-monospace,Menlo,monospace;
}
*{box-sizing:border-box}
html,body{margin:0}
body{background:var(--paper);color:var(--ink);font-family:var(--body);font-size:15px;line-height:1.55;-webkit-font-smoothing:antialiased}
h1,h2,h3{font-family:var(--display);letter-spacing:-.02em;margin:0;line-height:1.2}
h1{font-size:1.7rem}
h2{font-size:1.2rem}
h3{font-size:1rem}
a{color:var(--blue)}
:focus-visible{outline:3px solid var(--sky);outline-offset:2px;border-radius:6px}
.wrap{width:min(1180px,100% - 32px);margin-inline:auto}
.muted{color:var(--steel)}
.small{font-size:.85rem}
.mono{font-family:var(--mono);font-size:.85em}
[hidden]{display:none!important}

/* top bar */
header.top{position:sticky;top:0;z-index:30;background:#fff;border-bottom:1px solid var(--line)}
header.top .wrap{display:flex;align-items:center;gap:18px;min-height:64px;flex-wrap:wrap}
header.top .logo img{height:30px;display:block}
nav.tabs{display:flex;gap:4px}
nav.tabs a{padding:8px 12px;border-radius:8px;text-decoration:none;color:var(--steel);font-weight:500;font-size:.92rem}
nav.tabs a.on{background:var(--soft);color:var(--ink)}
.me{margin-left:auto;display:flex;align-items:center;gap:10px;font-size:.85rem}
.me select{font:inherit;font-size:.85rem;padding:6px 8px;border:1px solid var(--line);border-radius:8px;background:#fff;max-width:220px}
.av{width:32px;height:32px;border-radius:50%;background:var(--ink);color:#fff;display:grid;place-items:center;font-weight:600;font-size:.75rem;flex:0 0 auto}
.linkbtn{background:none;border:0;font:inherit;color:var(--steel);text-decoration:underline;cursor:pointer;padding:0}
@media(max-width:760px){nav.tabs{order:3;width:100%;overflow-x:auto}.me .nm{display:none}}

main{padding:28px 0 60px}
.head{display:flex;align-items:flex-end;gap:16px;flex-wrap:wrap;margin-bottom:20px}
.head .grow{flex:1;min-width:240px}
.crumb{font-size:.82rem;color:var(--steel);margin-bottom:6px}
.crumb a{color:var(--steel)}

.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:22px}
.card + .card{margin-top:16px}
.grid > .card{margin-top:0}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(270px,1fr));gap:16px}
.cls{display:block;text-decoration:none;color:inherit;background:#fff;border:1px solid var(--line);border-radius:14px;padding:18px;transition:border-color .15s,box-shadow .15s}
.cls:hover{border-color:#A9BFD0;box-shadow:0 8px 24px -16px rgba(20,32,44,.4)}
.cls h3{margin-bottom:4px}
.cls .meta{font-size:.84rem;color:var(--steel)}
.cls .stats{display:flex;gap:16px;margin-top:12px;font-size:.84rem}
.cls .stats b{font-size:1.1rem;display:block}
.cls.archived{opacity:.6}

.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:40px;padding:0 16px;border-radius:10px;border:1px solid var(--ink);background:var(--ink);color:#fff;font:inherit;font-weight:600;font-size:.9rem;cursor:pointer;text-decoration:none;white-space:nowrap}
.btn:hover{background:#26384A}
.btn.ghost{background:#fff;color:var(--ink);border-color:var(--line)}
.btn.ghost:hover{border-color:var(--ink)}
.btn.blue{background:var(--blue);border-color:var(--blue)}
.btn.danger{background:#fff;color:var(--bad);border-color:#F2C9C9}
.btn.sm{min-height:32px;padding:0 10px;font-size:.82rem}
.btn[disabled]{opacity:.55;cursor:default}

form.stack{display:grid;gap:14px}
label{display:block;font-weight:600;font-size:.85rem;margin-bottom:5px}
.hint{font-weight:400;color:var(--steel);font-size:.8rem}
input[type=text],input[type=email],input[type=date],select,textarea{width:100%;font:inherit;padding:9px 11px;border:1px solid #C5CED8;border-radius:9px;background:#fff;color:var(--ink)}
textarea{min-height:120px;font-family:var(--mono);font-size:.85rem}
.checks{display:flex;flex-wrap:wrap;gap:8px}
.checks label{display:inline-flex;align-items:center;gap:7px;font-weight:500;font-size:.86rem;border:1px solid var(--line);border-radius:999px;padding:5px 12px 5px 9px;margin:0;cursor:pointer;background:#fff}
.checks input{margin:0}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
@media(max-width:640px){.row2{grid-template-columns:1fr}}

.tabbar{display:flex;gap:4px;border-bottom:1px solid var(--line);margin:0 0 18px;overflow-x:auto}
.tabbar button{background:none;border:0;border-bottom:2px solid transparent;padding:10px 14px;font:inherit;font-weight:600;color:var(--steel);cursor:pointer;white-space:nowrap}
.tabbar button.on{color:var(--ink);border-bottom-color:var(--blue)}

.tablewrap{overflow-x:auto;border:1px solid var(--line);border-radius:12px;background:#fff}
table{width:100%;border-collapse:collapse;font-size:.88rem}
th{text-align:left;font-weight:600;font-size:.76rem;color:var(--steel);padding:10px 12px;border-bottom:1px solid var(--line);white-space:nowrap;background:var(--soft)}
td{padding:10px 12px;border-bottom:1px solid #EDF0F3;vertical-align:middle}
tr:last-child td{border-bottom:0}
td.num,th.num{text-align:center}
.score{display:inline-block;min-width:44px;padding:2px 8px;border-radius:6px;font-weight:600;font-variant-numeric:tabular-nums}
.score small{font-weight:400;color:var(--steel)}
.s-hi{background:var(--ok-bg);color:var(--ok)}
.s-mid{background:var(--mid-bg);color:var(--mid)}
.s-lo{background:var(--bad-bg);color:var(--bad)}
.s-none{color:#A8B2BC}

.pill{display:inline-block;font-size:.74rem;font-weight:600;padding:2px 9px;border-radius:999px;background:var(--soft);border:1px solid var(--line)}
.pill.admin{background:#E3EEF7;border-color:#C5DCEC}
.pill.tutor{background:var(--sky-bg);border-color:#BFE1EF}
.pill.learner{background:#FFF8DD;border-color:#F2E2A6}
.pill.invited{background:#fff;border-style:dashed}

.code{font-family:var(--mono);font-size:1.5rem;letter-spacing:.18em;font-weight:600;background:var(--soft);border:1px dashed #B9C6D2;border-radius:10px;padding:6px 14px;display:inline-block}
.bar{height:8px;border-radius:4px;background:#EDF0F3;overflow:hidden;min-width:80px}
.bar i{display:block;height:100%;background:var(--bad)}
.empty{text-align:center;padding:40px 20px;color:var(--steel)}
.empty h3{color:var(--ink);margin-bottom:6px}
.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%);background:var(--ink);color:#fff;padding:12px 18px;border-radius:10px;font-size:.9rem;z-index:50;box-shadow:0 10px 30px -10px rgba(0,0,0,.5)}
.toast.err{background:var(--bad)}
.err{color:var(--bad)}
.mod{display:flex;align-items:center;gap:14px;padding:14px 0;border-bottom:1px solid #EDF0F3}
.mod:last-child{border-bottom:0}
.mod .t{flex:1}
.mod .t b{display:block}
.loading{padding:60px 0;text-align:center;color:var(--steel)}
.stats3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-bottom:16px;max-width:720px}
.stats3 .card{padding:14px 16px;margin:0}
.stats3 .v{font-family:var(--display);font-size:1.45rem;font-weight:700;line-height:1.2}
@media(max-width:560px){.stats3 .card{padding:10px 12px}.stats3 .v{font-size:1.1rem}.stats3 .small{font-size:.74rem}}

/* AI insights */
.ins-bar{display:flex;gap:18px;align-items:flex-start;flex-wrap:wrap;margin:14px 0 16px}
.ins-bar .grow{flex:1;min-width:240px;display:grid;gap:6px}
.ins-act{display:grid;gap:8px;justify-items:start}
.chk{display:flex;gap:8px;align-items:center;font-weight:400;margin:0}
.chk input{width:auto;margin:0}
.ins h3{font-size:1.15rem;margin:8px 0 12px;line-height:1.3}
.ins.latest{border-color:#9ED8EE;box-shadow:0 0 0 3px #E6F4FA}
.ins.pending{background:var(--soft)}
.ins-meta{font-size:.8rem;color:var(--steel)}
.ins-meta .ai{display:inline-block;font-weight:700;font-size:.7rem;padding:1px 7px;border-radius:999px;background:linear-gradient(90deg,#7EE3FF,#1FB4EC);color:#00142C}
.ins-note{border-top:1px solid var(--line);padding:12px 0}
.ins-note p{margin:4px 0 8px}
.reteach{background:#EEF8FC;border-radius:8px;padding:9px 12px;font-size:.92rem}
.reteach b{color:#006F96}
.ins-sub{border-top:1px solid var(--line);padding-top:10px}
.ins-sub ul{margin:6px 0 0;padding-left:20px}
.ins-good{border-top:1px solid var(--line);padding-top:10px;margin:10px 0 0}

/* demo mode */
.demobar{background:linear-gradient(90deg,#00142C,#0B3A52);color:#E6F7FD;font-size:.86rem;position:relative;z-index:31}
.demobar .wrap{display:flex;align-items:center;gap:12px;flex-wrap:wrap;padding-top:8px;padding-bottom:8px}
.demobar .dl b{display:inline-block;background:linear-gradient(90deg,#7EE3FF,#1FB4EC);color:#00142C;border-radius:999px;padding:1px 9px;margin-right:6px;font-size:.75rem}
.demobar .seg{display:inline-flex;background:rgba(255,255,255,.08);border:1px solid rgba(126,227,255,.35);border-radius:999px;padding:3px}
.demobar .seg button{background:none;border:0;color:#CFEAF6;font:600 .82rem/1 inherit;font-family:inherit;padding:7px 13px;border-radius:999px;cursor:pointer}
.demobar .seg button.on{background:#7EE3FF;color:#00142C}
.demobar .exit{margin-left:auto;background:none;border:1px solid rgba(255,255,255,.35);color:#fff;border-radius:999px;padding:6px 13px;font:600 .8rem inherit;font-family:inherit;cursor:pointer}
.demo-card{display:flex;gap:18px;align-items:center;flex-wrap:wrap}
.demo-card .grow{flex:1;min-width:260px}
.demo-btns{display:flex;gap:8px;flex-wrap:wrap}
@media(max-width:560px){.demobar .exit{margin-left:0}.demobar .seg button{padding:7px 10px}}

/* ---------- course colours ---------- */
.ctop{position:relative;overflow:hidden}
.ctop::before{content:"";position:absolute;inset:0 0 auto 0;height:6px;background:var(--c,var(--blue))}
.cls.ctop{padding-top:22px}
.card.ctop{padding-top:26px}
.ctag{display:inline-flex;align-items:center;gap:6px;font-size:.72rem;font-weight:600;color:var(--steel);text-transform:uppercase;letter-spacing:.06em;margin-bottom:6px}
.ctag::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--c,var(--blue))}
.prog{height:6px;border-radius:999px;background:#EDF0F3;overflow:hidden;margin:0 0 6px}
.prog i{display:block;height:100%;border-radius:999px;background:var(--c,var(--blue));transition:width .4s}
.av{border:0;font-family:inherit;cursor:pointer;padding:0}
.av.lg{width:46px;height:46px;font-size:.95rem;cursor:default}
#view.enter{animation:lvIn .22s ease-out}
@keyframes lvIn{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
@media(prefers-reduced-motion:reduce){#view.enter{animation:none}.sheet-panel{transition:none!important}}

/* ---------- bottom bar and account sheet (phones) ---------- */
.bnav{display:none}
.sheet{position:fixed;inset:0;z-index:60}
.sheet-bg{position:absolute;inset:0;background:rgba(13,22,31,.45);opacity:0;transition:opacity .2s}
.sheet-panel{position:absolute;left:0;right:0;bottom:0;background:#fff;border-radius:20px 20px 0 0;padding:10px 18px calc(18px + env(safe-area-inset-bottom));max-height:86vh;overflow:auto;transform:translateY(100%);transition:transform .22s ease-out;box-shadow:0 -10px 40px -10px rgba(0,0,0,.35)}
.sheet.open .sheet-bg{opacity:1}
.sheet.open .sheet-panel{transform:none}
.grab{width:40px;height:5px;border-radius:999px;background:#D3DAE2;margin:2px auto 14px}
.sh-me{display:flex;gap:12px;align-items:center;padding:4px 2px 14px;border-bottom:1px solid var(--line)}
.sh-lb{margin:14px 0 6px}
.sh-list{display:grid;margin:10px 0;border:1px solid var(--line);border-radius:14px;overflow:hidden}
.sh-list a{display:flex;align-items:center;gap:14px;min-height:52px;padding:0 16px;color:var(--ink);text-decoration:none;font-weight:500;border-bottom:1px solid #EDF0F3}
.sh-list a:last-child{border-bottom:0}
.sh-list a.on{color:var(--blue)}
.sh-list svg,.bnav svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;flex:0 0 auto}
.btn.wide{width:100%;min-height:48px;margin-top:4px}
.sh-co{text-align:center;margin:14px 0 2px}
@media(min-width:761px){
  .sheet-panel{left:auto;right:24px;bottom:auto;top:76px;width:360px;border-radius:16px;transform:translateY(-8px);opacity:0;transition:transform .18s,opacity .18s}
  .sheet.open .sheet-panel{opacity:1}
  .sheet-bg{background:transparent}
  .grab{display:none}
}

@media(max-width:760px){
  html{-webkit-text-size-adjust:100%}
  body{font-size:15.5px;-webkit-tap-highlight-color:transparent;overscroll-behavior-y:none}
  header.top{padding-top:env(safe-area-inset-top);background:rgba(255,255,255,.92);backdrop-filter:saturate(1.6) blur(12px);-webkit-backdrop-filter:saturate(1.6) blur(12px)}
  header.top .wrap{min-height:56px;flex-wrap:nowrap}
  header.top .logo img{height:26px}
  nav.tabs,.me .nm,.me #out,.me #centrePick{display:none}
  .me{margin-left:auto}
  .av{width:36px;height:36px}
  main{padding:18px 0 calc(96px + env(safe-area-inset-bottom))}
  .wrap{width:calc(100% - 28px)}
  footer.lvf{display:none}
  h1{font-size:1.45rem}
  .head{margin-bottom:14px;gap:10px}
  .head .grow{min-width:0;flex-basis:100%}
  .head > .btn,.head > select{width:100%;min-height:46px}
  .card{border-radius:16px;padding:18px}
  .card.ctop{padding-top:22px}
  .grid{grid-template-columns:1fr;gap:12px}
  .cls{border-radius:16px;padding:16px 16px 14px;transition:transform .12s}
  .cls.ctop{padding-top:20px}
  .cls:active,.card.course:active{transform:scale(.985)}
  .btn{min-height:44px}
  .btn.sm{min-height:38px;padding:0 14px}
  input[type=text],input[type=email],input[type=date],select,textarea{font-size:16px;padding:11px 12px}
  .mod{gap:10px;flex-wrap:wrap}
  .mod .t{min-width:60%}
  .tabbar{position:sticky;top:calc(57px + env(safe-area-inset-top));z-index:20;background:var(--paper);margin:0 -14px 14px;padding:8px 14px;border-bottom:0;gap:8px;scrollbar-width:none}
  .tabbar::-webkit-scrollbar{display:none}
  .tabbar button{border:1px solid var(--line);border-radius:999px;background:#fff;padding:8px 14px;font-size:.88rem}
  .tabbar button.on{background:var(--ink);color:#fff;border-color:var(--ink)}
  .tablewrap{border-radius:14px}
  .tablewrap th:first-child,.tablewrap td:first-child{position:sticky;left:0;background:#fff;z-index:1;box-shadow:1px 0 0 #EDF0F3}
  .tablewrap th:first-child{background:var(--soft)}
  .toast{bottom:calc(84px + env(safe-area-inset-bottom));width:max-content;max-width:calc(100% - 32px);text-align:center}
  .demobar{font-size:.8rem}
  .demobar .wrap{padding-top:6px;padding-bottom:6px;gap:8px}
  .demobar .dl{flex-basis:100%}

  .bnav{display:grid;grid-template-columns:repeat(var(--bcount,5),1fr);position:fixed;left:0;right:0;bottom:0;z-index:40;background:rgba(255,255,255,.94);backdrop-filter:saturate(1.6) blur(14px);-webkit-backdrop-filter:saturate(1.6) blur(14px);border-top:1px solid var(--line);padding:6px 6px calc(6px + env(safe-area-inset-bottom))}
  .bnav a,.bnav button{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;min-height:52px;border-radius:12px;color:#7A8694;text-decoration:none;font:600 .68rem/1.1 var(--body);background:none;border:0;cursor:pointer;padding:0}
  .bnav .on{color:var(--ink)}
  .bnav .on svg{stroke:var(--blue);stroke-width:2.1}
  .bnav .on span{position:relative}
  .bnav a:active,.bnav button:active{background:var(--soft)}
}

/* ---------- phones: tables become tap-to-open rows; sideways menus show there is more ---------- */
.acc-t{display:none}
.tabscroll{position:relative}
@media(max-width:760px){
  .tabscroll{position:sticky;top:calc(57px + env(safe-area-inset-top));z-index:20;margin:0 -14px 14px}
  .tabscroll .tabbar{position:static;margin:0;scroll-snap-type:x proximity;scroll-padding-left:48px}
  .tabscroll .tabbar button{scroll-snap-align:start}
  .tabscroll::before,.tabscroll::after{content:"";position:absolute;top:0;bottom:0;width:44px;pointer-events:none;opacity:0;transition:opacity .2s;z-index:1}
  .tabscroll::before{left:0;background:linear-gradient(90deg,var(--paper) 30%,rgba(238,241,244,0))}
  .tabscroll::after{right:0;background:linear-gradient(270deg,var(--paper) 30%,rgba(238,241,244,0))}
  .tabscroll.more-l::before,.tabscroll.more-r::after{opacity:1}
  .tabscroll.more-r .tabbar{padding-right:44px}
  .tabscroll.more-r::after{background:linear-gradient(270deg,var(--paper) 30%,rgba(238,241,244,0)),no-repeat right 12px center/9px 14px url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 9 14'%3E%3Cpath d='M1.5 1.5L7 7l-5.5 5.5' fill='none' stroke='%2314202C' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");background-blend-mode:normal}
  .tabscroll.more-l::before{background:linear-gradient(90deg,var(--paper) 30%,rgba(238,241,244,0)),no-repeat left 12px center/9px 14px url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 9 14'%3E%3Cpath d='M7.5 1.5L2 7l5.5 5.5' fill='none' stroke='%2314202C' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E")}

  .tablewrap:has(table.acc){overflow:visible;background:#fff}
  table.acc,table.acc tbody{display:block;width:100%}
  table.acc thead{display:none}
  table.acc tr{display:grid;grid-template-columns:minmax(0,1fr) auto;column-gap:12px;align-items:center;position:relative;padding:14px 48px 14px 16px;border-bottom:1px solid #EDF0F3;cursor:pointer}
  table.acc tr:last-child{border-bottom:0}
  table.acc tr.acc-one{display:block;padding:14px 16px;cursor:default}
  table.acc td{display:none;border:0;padding:0;position:static!important;box-shadow:none!important;background:none!important;text-align:left}
  table.acc tr.acc-one td{display:block}
  table.acc td.acc-h{display:block;grid-column:1;grid-row:1;min-width:0;overflow-wrap:anywhere}
  table.acc td.peek{display:block;grid-column:2;grid-row:1;text-align:right;white-space:nowrap}
  table.acc tr.open{background:#FAFBFC}
  table.acc tr.open td:not(.acc-h):not(.peek){display:flex;justify-content:space-between;align-items:center;gap:14px;grid-column:1/-1;padding:9px 0;border-top:1px solid #EDF0F3;font-size:.9rem;text-align:right;overflow-wrap:anywhere}
  table.acc tr.open td:not(.acc-h):not(.peek)::before{content:attr(data-label);color:var(--steel);font-size:.8rem;font-weight:600;text-align:left;flex:0 0 auto;max-width:45%}
  table.acc tr.open td.acc-act{justify-content:flex-start;flex-wrap:wrap;gap:8px;padding-top:12px}
  table.acc tr.open td.acc-act::before{display:none}
  table.acc tr.open td:nth-child(2){margin-top:10px}
  table.acc .acc-t{display:block;position:absolute;right:8px;top:12px;width:36px;height:36px;border:0;border-radius:10px;background:none;cursor:pointer}
  table.acc .acc-t::after{content:"";position:absolute;left:13px;top:11px;width:8px;height:8px;border-right:2px solid var(--steel);border-bottom:2px solid var(--steel);transform:rotate(45deg);transition:transform .18s}
  table.acc tr.open .acc-t::after{transform:rotate(-135deg);top:15px}
  table.acc tr:active{background:var(--soft)}
}