:root{
  --paper:#F3F4F6; --card:#FFFFFF; --ink:#1A2230; --ink-2:#3F4A5A; --muted:#6E7887; --line:#D8DCE3; --line-2:#E8EBF0;
  --accent:#C8102E; --accent-soft:#FBE7EA; --navy:#1F3A5F; --navy-soft:#E4ECF6;
  --ok:#2E7D4F; --ok-soft:#E1F1E7; --warn:#B76E00; --warn-soft:#FFF1DA; --bad:#B3261E; --bad-soft:#FCE8E6;
  --answer:#F5F9FE; --answer-line:#B9C6D8; --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --shadow:0 1px 2px rgba(26,34,48,.06),0 4px 14px rgba(26,34,48,.06);
}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;background:var(--paper);color:var(--ink);font:15px/1.5 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif}
h1,h2,h3,h4{margin:0;line-height:1.2}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
a{color:var(--navy)}
[hidden]{display:none!important}
.mono{font-family:var(--mono);font-variant-numeric:tabular-nums}
.muted{color:var(--muted)}
.small{font-size:13px}
.pill{display:inline-block;padding:2px 9px;border-radius:999px;font-size:12px;font-weight:600;line-height:1.5}
.pill.ok{background:var(--ok-soft);color:var(--ok)} .pill.warn{background:var(--warn-soft);color:var(--warn)} .pill.bad{background:var(--bad-soft);color:var(--bad)} .pill.navy{background:var(--navy-soft);color:var(--navy)} .pill.grey{background:var(--line-2);color:var(--ink-2)}

.btn{display:inline-flex;align-items:center;gap:6px;padding:8px 14px;border-radius:6px;border:1px solid var(--line);background:var(--card);font-weight:600;font-size:14px;color:var(--ink)}
.btn:hover{background:var(--line-2)}
.btn.primary{background:var(--navy);border-color:var(--navy);color:#fff} .btn.primary:hover{background:#17304f}
.btn.danger{background:var(--accent);border-color:var(--accent);color:#fff}
.btn.sm{padding:5px 10px;font-size:13px}
.btn:disabled{opacity:.5;cursor:not-allowed}
.btn:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:2px solid var(--navy);outline-offset:1px}

.field{display:block;margin-bottom:12px}
.field span{display:block;font-size:13px;color:var(--ink-2);font-weight:600;margin-bottom:4px}
.field input,.field select,.field textarea{width:100%;padding:8px 10px;border:1px solid var(--line);border-radius:6px;background:#fff}

/* ---------- top bar ---------- */
.topbar{position:sticky;top:0;z-index:20;background:var(--card);border-bottom:1px solid var(--line);display:flex;align-items:center;gap:16px;padding:8px 16px;min-height:54px}
.brand{display:flex;align-items:baseline;gap:8px;font-weight:800;letter-spacing:-.01em}
.brand b{color:var(--accent);font-size:20px} .brand i{font-style:italic;font-weight:600;font-size:20px;color:var(--ink)}
.brand small{font-weight:500;color:var(--muted);font-size:12px}
.topbar .title{font-weight:600;color:var(--ink-2);flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.timer{font-family:var(--mono);font-size:20px;font-weight:600;padding:4px 12px;border-radius:6px;background:var(--navy-soft);color:var(--navy)}
.timer.warn{background:var(--warn-soft);color:var(--warn)} .timer.bad{background:var(--bad-soft);color:var(--bad)}
.savestate{font-size:12px;color:var(--muted);display:flex;align-items:center;gap:6px;white-space:nowrap}
.savestate i{width:8px;height:8px;border-radius:50%;background:var(--muted)} .savestate.ok i{background:var(--ok)} .savestate.bad i{background:var(--bad)} .savestate.pending i{background:var(--warn)}

/* ---------- layout ---------- */
.shell{display:grid;grid-template-columns:230px 1fr;min-height:calc(100vh - 54px)}
.sidebar{background:var(--card);border-right:1px solid var(--line);padding:14px 12px;position:sticky;top:54px;height:calc(100vh - 54px);overflow:auto}
.sidebar h3{font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin:0 4px 8px}
.qgrid{display:grid;grid-template-columns:repeat(4,1fr);gap:6px}
.qbtn{position:relative;border:1px solid var(--line);background:#fff;border-radius:6px;padding:8px 0;font-weight:600;font-size:14px;text-align:center}
.qbtn.partial{background:var(--warn-soft);border-color:#E9C98F} .qbtn.done{background:var(--ok-soft);border-color:#A8D5B7}
.qbtn.current{outline:2px solid var(--navy);outline-offset:-1px}
.qbtn.flag::after{content:"";position:absolute;top:3px;right:3px;width:7px;height:7px;border-radius:50%;background:var(--accent)}
.legend{margin-top:12px;font-size:12px;color:var(--muted);display:grid;gap:4px}
.legend span{display:flex;align-items:center;gap:6px}
.legend i{width:12px;height:12px;border-radius:3px;border:1px solid var(--line);display:inline-block}
.main{padding:20px 24px 80px;max-width:940px;width:100%}

/* ---------- question ---------- */
.qhead{display:flex;align-items:baseline;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:10px}
.qhead h2{font-size:22px;font-weight:800}
.qhead .marks{color:var(--muted);font-weight:500;font-size:15px}
.stem{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:16px 18px;box-shadow:var(--shadow);white-space:pre-wrap;line-height:1.55}
.stem .obs{font-family:var(--mono);font-size:13.5px;display:inline-grid;grid-template-columns:auto auto auto;column-gap:18px;row-gap:1px;background:var(--paper);padding:8px 12px;border-radius:6px;margin:4px 0}
.qimg{display:block;max-width:100%;max-height:520px;margin:12px auto 4px;border-radius:6px;background:#000}
.part{margin-top:18px}
.part .prompt{display:flex;gap:10px;font-weight:600;margin-bottom:8px;line-height:1.45}
.part .prompt b{color:var(--navy);flex:none;min-width:18px}
.part .prompt .pm{color:var(--muted);font-weight:500;white-space:nowrap}
.pre.small{font-size:13.5px;margin:10px 0 6px}
.pre{white-space:pre-wrap;margin:14px 0 8px;padding:10px 12px;border-left:3px solid var(--navy);background:var(--card);border-radius:0 6px 6px 0}
.abox{position:relative}
.abox textarea{display:block;width:100%;min-height:96px;padding:10px 12px;border:1.5px solid var(--answer-line);border-radius:6px;background:var(--answer);resize:vertical;line-height:1.5}
.abox textarea:focus{background:#fff}
.abox .count{position:absolute;right:8px;bottom:6px;font-size:11px;color:var(--muted);font-family:var(--mono);pointer-events:none;background:rgba(255,255,255,.7);padding:0 4px;border-radius:3px}
.abox .count.limit{color:var(--bad);font-weight:600}
.atable{width:100%;border-collapse:collapse;table-layout:fixed}
.atable th{background:var(--line-2);border:1px solid var(--line);padding:6px 8px;font-size:13.5px;text-align:center}
.atable td{border:1px solid var(--line);padding:4px;vertical-align:top}
.atable td.rl{background:var(--line-2);font-weight:600;font-size:13.5px;width:120px;padding:8px}
.atable td.skip{background:repeating-linear-gradient(45deg,var(--line-2),var(--line-2) 6px,#fff 6px,#fff 12px)}
.atable .abox textarea{min-height:72px;border-radius:4px}
.qnav{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-top:26px;padding-top:16px;border-top:1px solid var(--line);flex-wrap:wrap}
.flagbtn{border:1px solid var(--line);background:#fff;border-radius:6px;padding:6px 12px;font-size:13px;display:inline-flex;gap:6px;align-items:center}
.flagbtn.on{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}

/* ---------- panels ---------- */
.center{max-width:640px;margin:48px auto;padding:0 16px}
.card{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:22px 24px;box-shadow:var(--shadow)}
.card h1{font-size:22px;margin-bottom:6px}
.card ol{padding-left:20px} .card li{margin:4px 0}
.notice{padding:10px 14px;border-radius:6px;background:var(--warn-soft);color:var(--warn);font-size:14px;margin:12px 0}
.notice.bad{background:var(--bad-soft);color:var(--bad)} .notice.ok{background:var(--ok-soft);color:var(--ok)}

/* ---------- modal ---------- */
.modal{position:fixed;inset:0;background:rgba(20,26,36,.45);display:flex;align-items:center;justify-content:center;z-index:50;padding:16px}
.modal .card{max-width:460px;width:100%}
.modal .actions{display:flex;justify-content:flex-end;gap:8px;margin-top:16px}

/* ---------- marking ---------- */
.mark-shell{display:grid;grid-template-columns:260px 1fr;min-height:calc(100vh - 54px)}
.candlist{list-style:none;margin:0;padding:0}
.candlist li{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:7px 8px;border-radius:6px;font-size:14px;cursor:pointer}
.candlist li:hover{background:var(--line-2)} .candlist li.current{background:var(--navy-soft);font-weight:600}
.candlist .sc{font-family:var(--mono);font-size:12px;color:var(--muted)}
.candlist li.marked .sc{color:var(--ok);font-weight:600}
.ans{white-space:pre-wrap;background:var(--answer);border:1px solid var(--answer-line);border-radius:6px;padding:10px 12px;min-height:44px;line-height:1.5}
.ans.empty{color:var(--muted);font-style:italic}
.mtable{width:100%;border-collapse:collapse;table-layout:fixed}
.mtable th{background:var(--line-2);border:1px solid var(--line);padding:6px 8px;font-size:13px}
.mtable td{border:1px solid var(--line);padding:6px 8px;vertical-align:top;white-space:pre-wrap;font-size:14px}
.mtable td.rl{background:var(--line-2);font-weight:600;font-size:13px;width:110px}
.mtable td.skip{background:repeating-linear-gradient(45deg,var(--line-2),var(--line-2) 6px,#fff 6px,#fff 12px)}
.tick{display:inline-flex;align-items:center;gap:6px;font-size:13px;margin:4px 8px 0 0;user-select:none}
.tick input{width:18px;height:18px;accent-color:var(--ok);margin:0}
.tick.half input{accent-color:var(--accent)}
.segwrap{display:inline-flex;align-items:center;gap:6px;margin:2px 10px 2px 0}
.seglabel{font-size:12.5px;color:var(--ink-2)}
.seg{display:inline-flex;border:1px solid var(--line);border-radius:6px;overflow:hidden;background:#fff}
.seg button{border:0;background:transparent;padding:3px 9px;font-size:13px;font-weight:600;color:var(--muted);min-width:30px;border-right:1px solid var(--line)}
.seg button:last-child{border-right:0}
.seg button:hover{background:var(--line-2)}
.seg button.on{color:#fff}
.seg button.on[data-v="0"]{background:var(--muted)} .seg button.on[data-v="0.5"]{background:var(--warn)} .seg button.on[data-v="1"]{background:var(--ok)}
.markrow{display:flex;flex-wrap:wrap;align-items:center;gap:4px 12px;margin-top:8px;padding:8px 10px;background:var(--card);border:1px dashed var(--line);border-radius:6px}
.markrow .score{margin-left:auto;font-family:var(--mono);font-weight:700;font-size:15px;color:var(--navy)}
.markrow textarea{width:100%;min-height:36px;padding:6px 8px;border:1px solid var(--line);border-radius:4px;font-size:13px;margin-top:6px}
.model{margin-top:8px;padding:8px 12px;border-radius:6px;background:var(--ok-soft);border:1px solid #BFE0C9;font-size:13.5px;white-space:pre-wrap}
.model b{color:var(--ok);font-size:12px;text-transform:uppercase;letter-spacing:.04em}
.model summary{cursor:pointer;font-weight:600;color:var(--ok)}
.model-table{border-collapse:collapse;width:100%;margin-top:2px;white-space:normal;font-size:13px;background:#fff}
.model-table th,.model-table td{border:1px solid #BFE0C9;padding:5px 8px;text-align:left;vertical-align:top;white-space:pre-wrap}
.model-table th{background:var(--ok-soft);font-weight:600}
.qtotal{position:sticky;bottom:0;background:var(--card);border-top:1px solid var(--line);padding:10px 16px;display:flex;justify-content:space-between;align-items:center;gap:10px;margin:20px -24px -80px;flex-wrap:wrap}
.qtotal .big{font-family:var(--mono);font-size:22px;font-weight:800;color:var(--navy)}

/* ---------- tables (admin) ---------- */
.tbl{width:100%;border-collapse:collapse;font-size:14px;background:var(--card);border:1px solid var(--line);border-radius:8px;overflow:hidden}
.tbl th{text-align:left;background:var(--line-2);padding:8px 10px;font-size:12px;text-transform:uppercase;letter-spacing:.04em;color:var(--ink-2)}
.tbl td{padding:8px 10px;border-top:1px solid var(--line-2);vertical-align:middle}
.tbl td.num{font-family:var(--mono);text-align:right}
.tblwrap{overflow-x:auto}
.toolbar{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin:14px 0}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.editor .q{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:14px 16px;margin-bottom:12px}
.editor .q summary{cursor:pointer;font-weight:700;font-size:16px}
.editor .p{border:1px solid var(--line-2);border-radius:6px;padding:10px 12px;margin-top:10px;background:var(--paper)}
.editor .row{display:flex;flex-wrap:wrap;gap:8px;align-items:end}
.editor .row .field{flex:1;min-width:120px;margin:0}
.editor textarea{min-height:64px}
.progress{height:8px;background:var(--line-2);border-radius:4px;overflow:hidden;min-width:80px}
.progress i{display:block;height:100%;background:var(--ok)}

@media (max-width:800px){
  .shell,.mark-shell{grid-template-columns:1fr}
  .sidebar{position:static;height:auto;border-right:0;border-bottom:1px solid var(--line)}
  .qgrid{grid-template-columns:repeat(7,1fr)}
  .main{padding:16px 16px 80px}
  .grid2{grid-template-columns:1fr}
  .topbar{flex-wrap:wrap}
}
@media print{
  .topbar,.sidebar,.qnav,.btn{display:none!important}
  .shell{display:block} .main{max-width:none;padding:0}
  .abox textarea{border:1px solid #999;background:#fff}
}

/* ---------- group marking ---------- */
.candlist li.disagree{background:var(--warn-soft)} .candlist li.agreed{background:var(--navy-soft)} .candlist li.marked{background:var(--ok-soft)}
.candlist li.current{outline:2px solid var(--navy);outline-offset:-2px}
.group{margin-top:8px;border:1px solid var(--line);border-radius:6px;background:var(--card);overflow:hidden}
.ghead{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:6px 10px;background:var(--line-2);font-size:13px;flex-wrap:wrap}
.grow{display:grid;grid-template-columns:110px auto 44px 1fr auto;gap:10px;align-items:center;padding:6px 10px;border-top:1px solid var(--line-2);font-size:13px}
.grow.me{background:var(--answer)} .grow.agreed{background:var(--navy-soft);font-weight:600}
.gname{font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.gscore{text-align:right;font-weight:700}
.gcomment{font-size:12.5px;white-space:pre-wrap}
.chips{display:inline-flex;gap:3px;flex-wrap:wrap}
.chips i{font-style:normal;display:inline-block;min-width:20px;text-align:center;font-size:11px;font-weight:700;border-radius:4px;padding:1px 3px;color:#fff}
.chips .c1{background:var(--ok)} .chips .ch{background:var(--warn)} .chips .c0{background:var(--line);color:var(--muted)}
.detail{margin-top:6px;display:grid;gap:8px}
.detail .mycomment{width:100%;min-height:40px;padding:6px 8px;border:1px solid var(--line);border-radius:4px;font-size:13px}
.sidebar .tog{display:flex;gap:6px;align-items:center;margin:0;font-size:13px;color:var(--ink-2)}
.markrow .pill{max-width:100%;white-space:normal}
.notes{margin-top:0;border:1px dashed var(--line);border-radius:6px;padding:6px 10px;background:var(--card);font-size:13.5px}
.notes summary{cursor:pointer;font-weight:600;color:var(--ink-2);font-size:13px}
.note{padding:6px 0;border-top:1px solid var(--line-2)} .note.me b{color:var(--navy)} .note .del{margin-top:0}
.noteform{display:flex;gap:6px;margin-top:8px} .noteform input{flex:1;padding:6px 9px;border:1px solid var(--line);border-radius:6px;font-size:13.5px}
@media (max-width:800px){ .grow{grid-template-columns:1fr auto;} .grow .gcomment, .grow.agreedit .gcomment{grid-column:1/-1 !important} }

/* candidate-at-a-time marking */
.candpick{font:inherit;font-size:13px;padding:3px 8px;border:1px solid var(--line);border-radius:6px;background:var(--card);color:var(--ink);max-width:220px}
.qtotal .big{white-space:nowrap}
@media (max-width:800px){ .qhead .candpick{max-width:150px} }
/* reading time: questions visible, answer boxes locked */
.timer.reading{background:var(--ok-soft);color:var(--ok)}
.notice.reading-banner{background:var(--ok-soft);color:var(--ok);border-left:4px solid var(--ok)}
.abox textarea[readonly]{background:var(--line-2);border-style:dashed;cursor:not-allowed}
.abox textarea[readonly]:focus{background:var(--line-2)}
/* admin: personal links */
.linkcell{display:flex;gap:6px;align-items:center;white-space:nowrap}
.linkcell code{font-size:11px;max-width:120px;overflow:hidden;text-overflow:ellipsis;display:inline-block;vertical-align:middle}
.grow.agreedit{background:#F4F7FB;border-top:1px dashed #C9D3E0;align-items:start}
.grow.agreedit .mycomment{width:100%;min-height:38px;margin:0}
/* MCQ options */
.part.mcq{display:flex;flex-direction:column;gap:8px}
.mcqopt{display:flex;align-items:flex-start;gap:12px;width:100%;text-align:left;padding:12px 14px;border:1.5px solid var(--line);border-radius:10px;background:#fff;font:inherit;color:inherit;cursor:pointer}
.mcqopt:hover:not(:disabled){border-color:var(--navy)}
.mcqopt.on{border-color:var(--navy);background:var(--navy-soft);box-shadow:inset 0 0 0 1px var(--navy)}
.mcqopt:disabled{cursor:not-allowed;opacity:.7}
.mcqletter{flex:0 0 28px;height:28px;border-radius:50%;border:1.5px solid var(--line);display:grid;place-items:center;font-weight:700}
.mcqopt.on .mcqletter{background:var(--navy);border-color:var(--navy);color:#fff}
.mcqtext{flex:1;padding-top:3px;white-space:pre-wrap}
.mcqopt.result{cursor:default}
.mcqopt.result.key{border-color:var(--ok);background:var(--ok-soft)}
.mcqopt.result.wrong{border-color:var(--bad);background:var(--bad-soft)}
.mcqtag{font-size:12.5px;font-weight:600;padding-top:5px;color:var(--muted)}
.mcqopt.result.key .mcqtag{color:var(--ok)}