:root{
  --bg:#eef2f8;
  --surface:#ffffff;
  --surface-alt:#f8fafc;
  --border:#d9e2ec;
  --border-strong:#c2cee0;
  --ink:#16233a;
  --ink-dim:#5b6b82;
  --ink-faint:#8695ab;
  --brand:#0f62fe;
  --brand-ink:#0a3d91;
  --brand-soft:#e7f0ff;
  --header-bg:#0c2340;
  --header-bg-2:#123a63;
  --good:#16803c;
  --good-bg:#e8f7ee;
  --good-border:#bfe3cc;
  --bad:#c81e1e;
  --bad-bg:#fdeaea;
  --bad-border:#f2c1c1;
  --warn:#b45309;
  --warn-bg:#fff4e0;
  --warn-border:#f3d9a4;
  --paper:#fffdf6;
  --paper-line:#cfd9ea;
  --paper-ink:#20304a;
  --paper-ink-soft:#3c5170;
  --shadow: 0 10px 30px -12px rgba(12,35,64,.25);
  color-scheme: light;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --bg:#0a1320;
    --surface:#111c2c;
    --surface-alt:#0d1726;
    --border:#243349;
    --border-strong:#324a68;
    --ink:#e7edf7;
    --ink-dim:#9aa9c2;
    --ink-faint:#6d7d97;
    --brand:#5b9bff;
    --brand-ink:#bcd7ff;
    --brand-soft:#132745;
    --header-bg:#071322;
    --header-bg-2:#0d2036;
    --good:#3ddc97;
    --good-bg:rgba(61,220,151,.12);
    --good-border:rgba(61,220,151,.35);
    --bad:#ff8080;
    --bad-bg:rgba(255,128,128,.12);
    --bad-border:rgba(255,128,128,.35);
    --warn:#f5b955;
    --warn-bg:rgba(245,185,85,.12);
    --warn-border:rgba(245,185,85,.35);
    --shadow: 0 10px 30px -12px rgba(0,0,0,.55);
    color-scheme: dark;
  }
}
:root[data-theme="dark"]{
  --bg:#0a1320;
  --surface:#111c2c;
  --surface-alt:#0d1726;
  --border:#243349;
  --border-strong:#324a68;
  --ink:#e7edf7;
  --ink-dim:#9aa9c2;
  --ink-faint:#6d7d97;
  --brand:#5b9bff;
  --brand-ink:#bcd7ff;
  --brand-soft:#132745;
  --header-bg:#071322;
  --header-bg-2:#0d2036;
  --good:#3ddc97;
  --good-bg:rgba(61,220,151,.12);
  --good-border:rgba(61,220,151,.35);
  --bad:#ff8080;
  --bad-bg:rgba(255,128,128,.12);
  --bad-border:rgba(255,128,128,.35);
  --warn:#f5b955;
  --warn-bg:rgba(245,185,85,.12);
  --warn-border:rgba(245,185,85,.35);
  --shadow: 0 10px 30px -12px rgba(0,0,0,.55);
  color-scheme: dark;
}

*{box-sizing:border-box;}
[hidden]{display:none !important;}
html,body{margin:0; padding:0;}
body{
  background:var(--bg);
  color:var(--ink);
  font-family:'Source Sans 3', 'Segoe UI', Arial, sans-serif;
  padding-inline:0;
}
h1,h2,h3,h4{font-family:'Manrope','Segoe UI',Arial,sans-serif; margin:0; text-wrap:balance;}
.num{font-family:'JetBrains Mono', ui-monospace, Consolas, monospace; font-variant-numeric:tabular-nums;}
button{font-family:inherit;}
::selection{background:var(--brand); color:#fff;}

.app{
  max-width:1500px;
  margin:0 auto;
  padding: 0 18px 28px;
}

/* ---------- Top bar ---------- */
.topbar{
  position:sticky; top:env(safe-area-inset-top,0px);
  z-index:40;
  margin:0 -18px;
  padding:12px 22px;
  background:linear-gradient(155deg,var(--header-bg),var(--header-bg-2));
  color:#eaf1ff;
  display:flex; align-items:center; justify-content:space-between; gap:16px;
  flex-wrap:wrap;
  box-shadow: 0 6px 20px -10px rgba(0,0,0,.5);
}
.topbar-left{display:flex; align-items:center; gap:16px; min-width:0;}
.backlink{
  color:#c7d7f3; text-decoration:none; font-size:13px; font-weight:600;
  padding:6px 10px; border-radius:8px; border:1px solid rgba(255,255,255,.16);
  white-space:nowrap;
}
.backlink:hover{background:rgba(255,255,255,.08); color:#fff;}
.crumb{display:flex; align-items:baseline; gap:8px; min-width:0; flex-wrap:wrap;}
.crumb-course{font-size:12px; color:#9db6e6; font-weight:600; letter-spacing:.02em;}
.crumb-sep{color:#4d6690;}
.crumb-script{font-family:'Manrope'; font-size:17px; font-weight:800; letter-spacing:.01em;}
.crumb-script strong{color:#fff; font-family:'JetBrains Mono'; font-weight:700;}

.topbar-right{display:flex; align-items:center; gap:10px; flex-wrap:wrap;}
.timer{
  font-family:'JetBrains Mono'; font-size:13px; font-weight:600;
  background:rgba(255,255,255,.08); border:1px solid rgba(255,255,255,.14);
  padding:6px 10px; border-radius:8px; color:#dce8ff;
}
.status-badge{
  font-size:12px; font-weight:700; padding:6px 12px; border-radius:999px;
  background:var(--brand-soft); color:#1d4ed8; border:1px solid #bcd4ff;
}
.status-badge[data-state="progress"]{background:#1e3a66; color:#bfe0ff; border-color:#2d5590;}
.status-badge[data-state="submitted"]{background:#123f28; color:#8fe6b3; border-color:#1f5c3a;}
.evaluator{display:flex; align-items:center; gap:8px; padding-left:6px; border-left:1px solid rgba(255,255,255,.18);}
.avatar{
  width:28px; height:28px; border-radius:50%; background:#3b6fd6; color:#fff;
  display:flex; align-items:center; justify-content:center; font-size:11px; font-weight:800;
  font-family:'Manrope';
}
.evaluator-name{font-size:13px; font-weight:600; color:#eaf1ff;}

/* ---------- Workspace ---------- */
.workspace{
  display:grid; grid-template-columns: minmax(0,1fr) 400px; gap:16px;
  margin-top:14px;
}
@media (max-width:980px){
  .workspace{grid-template-columns: 1fr;}
}

.card{
  background:var(--surface); border:1px solid var(--border); border-radius:14px;
  box-shadow:var(--shadow);
}

/* ---------- Viewer pane ---------- */
.viewer-pane{display:flex; flex-direction:column; min-width:0;}
.toolbar{
  display:flex; align-items:center; gap:10px; flex-wrap:wrap;
  background:var(--surface); border:1px solid var(--border); border-radius:12px;
  padding:9px 10px; margin-bottom:12px; box-shadow:var(--shadow);
}
.tool-group{display:flex; align-items:center; gap:6px; padding-right:10px; border-right:1px solid var(--border);}
.tool-group:last-child{border-right:0;}
.tbtn{
  display:flex; align-items:center; gap:6px;
  border:1px solid var(--border); background:var(--surface-alt); color:var(--ink);
  border-radius:8px; padding:7px 10px; font-size:12.5px; font-weight:600; cursor:pointer;
  white-space:nowrap;
}
.tbtn:hover{border-color:var(--border-strong);}
.tbtn .kbd{
  font-family:'JetBrains Mono'; font-size:10px; color:var(--ink-faint);
  background:var(--bg); border:1px solid var(--border); border-radius:4px; padding:0 4px;
}
.tbtn.active{background:var(--brand); border-color:var(--brand); color:#fff;}
.tbtn.active .kbd{background:rgba(255,255,255,.2); border-color:rgba(255,255,255,.3); color:#fff;}
.tbtn.icon-only{padding:7px 9px;}
.swatch-label{font-size:10.5px; font-weight:700; text-transform:uppercase; letter-spacing:.03em; color:var(--ink-faint); margin-right:2px;}
.swatch{
  width:20px; height:20px; border-radius:50%; border:2px solid transparent; padding:0; cursor:pointer;
  box-shadow:0 0 0 1px var(--border);
}
.swatch.active{border-color:var(--surface); box-shadow:0 0 0 2px var(--ink);}
#colorPicker{
  width:26px; height:26px; padding:0; border:1px solid var(--border); border-radius:6px; cursor:pointer;
  background:none;
}
.zoom-label{font-family:'JetBrains Mono'; font-size:12px; color:var(--ink-dim); min-width:38px; text-align:center;}
.page-nav{display:flex; align-items:center; gap:6px; margin-left:auto;}
.page-count{font-family:'JetBrains Mono'; font-size:12.5px; color:var(--ink-dim);}

.viewer-scroll{
  position:relative; display:flex; gap:12px;
  background:var(--surface-alt); border:1px solid var(--border); border-radius:14px;
  padding:14px; height: calc(100vh - 250px); min-height:520px;
}
.viewer-scroll.drag-over{outline:3px dashed var(--brand); outline-offset:-3px; background:var(--brand-soft);}
.render-overlay{
  position:absolute; inset:0; z-index:30; border-radius:14px;
  background:rgba(10,19,32,.6); backdrop-filter:blur(1px);
  align-items:center; justify-content:center; flex-direction:column; gap:10px;
  color:#fff; font-family:'Manrope'; font-weight:700; font-size:13px; text-align:center; padding:20px;
}
.render-overlay:not([hidden]){display:flex;}
.spinner{width:32px; height:32px; border-radius:50%; border:3px solid rgba(255,255,255,.25); border-top-color:#fff; animation:spin .8s linear infinite;}
@keyframes spin{to{transform:rotate(360deg);}}
.upload-hint{font-size:11px; color:var(--ink-faint); margin:-4px 0 10px 2px;}
.thumbs{
  display:flex; flex-direction:column; gap:10px; overflow-y:auto; flex:none; width:74px;
}
.thumb{
  width:74px; height:96px; border-radius:6px; border:2px solid var(--border);
  background:var(--paper); cursor:pointer; position:relative; overflow:hidden; flex:none;
  background-image: repeating-linear-gradient(var(--paper) 0 11px, var(--paper-line) 11px 12px);
}
.thumb.active{border-color:var(--brand); box-shadow:0 0 0 3px var(--brand-soft);}
.thumb .tnum{
  position:absolute; bottom:3px; right:5px; font-family:'JetBrains Mono'; font-size:10px;
  color:var(--paper-ink-soft); background:rgba(255,255,255,.7); padding:0 3px; border-radius:3px;
}

.pages{flex:1; overflow-y:auto; padding-right:4px; scroll-behavior:smooth;}
.page-wrap{
  position:relative; background:var(--paper); margin:0 auto 22px; width: var(--page-width, 760px);
  max-width:100%; box-shadow:0 8px 26px rgba(0,0,0,.28); border-radius:3px; overflow:hidden;
}
.page-inner{position:relative; padding:26px 30px 34px; min-height:600px;
  background-image: repeating-linear-gradient(var(--paper) 0 27px, var(--paper-line) 27px 28px);
  background-position: 0 64px;
}
.page-wrap.scan-page{background:var(--paper);}
.script-page{display:block; width:100%; height:auto;}
.scan-tag{
  position:absolute; top:8px; left:8px; z-index:2; font-family:'JetBrains Mono'; font-size:10px;
  font-weight:700; letter-spacing:.03em; text-transform:uppercase; color:#0a3d91; background:#eaf1ff;
  border:1px solid #bcd4ff; border-radius:5px; padding:2px 7px; pointer-events:none;
}
.page-head{display:flex; justify-content:space-between; align-items:flex-start; margin-bottom:10px; font-family:'JetBrains Mono'; font-size:10.5px; color:var(--paper-ink-soft);}
.page-head .barcode{display:flex; gap:1.5px; align-items:flex-end; height:20px;}
.page-head .barcode span{width:2px; background:var(--paper-ink-soft); display:block;}
.stamp-layer{position:absolute; inset:0; cursor:crosshair;}
.stamp{position:absolute; transform:translate(-50%,-50%); font-weight:800; user-select:none; cursor:grab; line-height:1; touch-action:none;}
.stamp.tick{color:#0f9d58; font-size:30px; text-shadow:0 1px 1px rgba(0,0,0,.15);}
.stamp.cross{color:#d93025; font-size:30px; text-shadow:0 1px 1px rgba(0,0,0,.15);}
.stamp.marks{
  color:#0f62fe; border:2px solid #0f62fe; border-radius:50%; background:#fff;
  padding:5px 9px; font-size:14px; font-family:'JetBrains Mono'; box-shadow:0 2px 6px rgba(0,0,0,.2);
}
.stamp.text{
  color:#3d2c00; background:#fff3cd; border:1px solid #e8b923; border-radius:6px;
  padding:4px 8px; font-size:13px; font-family:'Source Sans 3'; font-weight:600; max-width:190px;
  box-shadow:0 2px 6px rgba(0,0,0,.18);
}
.stamp:hover::after{
  content:"drag · ✕ remove"; position:absolute; left:50%; top:-20px; transform:translateX(-50%);
  font-size:9px; font-weight:700; color:#fff; background:#1f2937; padding:2px 6px; border-radius:4px;
  white-space:nowrap;
}
.stamp.highlight-box, .stamp.underline-line{transform:none; touch-action:none;}
.stamp.highlight-box{
  border-radius:2px; mix-blend-mode:multiply; cursor:grab;
}
.stamp.highlight-box:hover::after{top:-20px; left:0; transform:none;}
.stamp.underline-line{
  height:4px; border-radius:2px; cursor:grab;
}
.stamp.underline-line:hover::after{top:-20px; left:0; transform:none;}
.pen-svg{position:absolute; inset:0; width:100%; height:100%; pointer-events:none; overflow:visible;}
.pen-svg path{pointer-events:stroke; cursor:grab; touch-action:none;}

.ans{font-family:'Kalam','Segoe UI',cursive; color:var(--paper-ink); font-size:19px; line-height:28px;}
.ans .strike{text-decoration:line-through; text-decoration-color:#c0392b; text-decoration-thickness:2px;}
.qtag{
  display:inline-block; font-family:'Manrope'; font-weight:800; font-size:13px;
  color:#1d4ed8; background:#e7f0ff; border-radius:5px; padding:1px 7px; margin-bottom:6px;
}
.printed{font-family:'Source Sans 3'; color:var(--paper-ink); font-size:13.5px; line-height:1.55;}
.cover-title{font-family:'Manrope'; font-weight:800; font-size:20px; color:var(--paper-ink); text-align:center; margin-bottom:4px;}
.cover-sub{font-family:'Source Sans 3'; font-size:12.5px; color:var(--paper-ink-soft); text-align:center; margin-bottom:20px;}
.cover-grid{display:grid; grid-template-columns:1fr 1fr; gap:10px 22px; font-size:13px; font-family:'Source Sans 3'; color:var(--paper-ink); max-width:520px; margin:0 auto 22px;}
.cover-grid b{font-family:'JetBrains Mono'; font-weight:700;}
.cover-box{border:1.5px solid var(--paper-ink-soft); border-radius:6px; padding:14px 18px; max-width:520px; margin:0 auto;}
.sigline{margin-top:34px; display:flex; justify-content:space-between; max-width:520px; margin-inline:auto; font-size:12px; color:var(--paper-ink-soft); font-family:'Source Sans 3';}
.sigline span{display:block; border-top:1px solid var(--paper-ink-soft); padding-top:4px; width:150px; text-align:center;}

/* ---------- Mark pane ---------- */
.mark-pane{display:flex; flex-direction:column; gap:12px; min-width:0;}
.mark-pane .card{padding:16px;}

.summary-head{display:flex; justify-content:space-between; align-items:baseline; margin-bottom:10px;}
.summary-head h3{font-size:14px; letter-spacing:.02em; color:var(--ink-dim); text-transform:uppercase;}
.autosave{font-size:11px; color:var(--ink-faint); display:flex; align-items:center; gap:5px;}
.autosave .dot{width:6px; height:6px; border-radius:50%; background:var(--good);}

.score-row{display:flex; align-items:center; gap:16px;}
.score-ring{position:relative; width:78px; height:78px; flex:none;}
.score-ring svg{transform:rotate(-90deg);}
.score-ring .ring-bg{fill:none; stroke:var(--border); stroke-width:9;}
.score-ring .ring-fg{fill:none; stroke:var(--brand); stroke-width:9; stroke-linecap:round; transition:stroke-dashoffset .3s ease;}
.score-ring .ring-txt{
  position:absolute; inset:0; display:flex; align-items:center; justify-content:center;
  flex-direction:column;
}
.score-ring .ring-txt b{font-family:'JetBrains Mono'; font-size:18px; line-height:1;}
.score-ring .ring-txt small{font-size:9.5px; color:var(--ink-faint);}
.score-detail{flex:1;}
.score-detail .big{font-family:'JetBrains Mono'; font-size:26px; font-weight:700;}
.score-detail .big span{color:var(--ink-faint); font-size:16px; font-weight:500;}
.score-detail .lbl{font-size:12px; color:var(--ink-dim); margin-top:2px;}
.score-bar{height:7px; border-radius:999px; background:var(--border); margin-top:10px; overflow:hidden;}
.score-bar > i{display:block; height:100%; background:linear-gradient(90deg,var(--brand),#57a6ff); border-radius:999px; transition:width .3s ease;}

.qtitle{display:flex; align-items:center; justify-content:between; gap:8px; margin-bottom:10px;}
.qtitle h3{font-size:14px; letter-spacing:.02em; color:var(--ink-dim); text-transform:uppercase;}
table.marks{width:100%; border-collapse:collapse; font-size:13px;}
table.marks th{
  text-align:left; font-family:'Manrope'; font-size:10.5px; letter-spacing:.04em; text-transform:uppercase;
  color:var(--ink-faint); border-bottom:1px solid var(--border); padding:0 6px 8px;
}
table.marks td{padding:7px 6px; border-bottom:1px solid var(--border); vertical-align:middle;}
table.marks tr:last-child td{border-bottom:0;}
table.marks .qno{font-family:'JetBrains Mono'; font-weight:700; color:var(--ink);}
table.marks .max{font-family:'JetBrains Mono'; color:var(--ink-faint); font-size:12.5px;}
.award-input{
  width:56px; text-align:center; font-family:'JetBrains Mono'; font-weight:700; font-size:13px;
  border:1px solid var(--border); border-radius:7px; padding:5px 4px; background:var(--surface-alt); color:var(--ink);
}
.award-input:focus{outline:2px solid var(--brand); outline-offset:1px; border-color:var(--brand);}
.award-input.exceed{border-color:var(--bad); background:var(--bad-bg); color:var(--bad);}
.remark-input{
  width:100%; border:1px solid var(--border); border-radius:7px; padding:5px 8px; font-size:12.5px;
  background:var(--surface-alt); color:var(--ink);
}
.remark-input:focus{outline:2px solid var(--brand); outline-offset:1px; border-color:var(--brand);}
.row-done{background:var(--good-bg);}
.row-pending .qno::after{
  content:"pending"; margin-left:6px; font-family:'Manrope'; font-size:9px; font-weight:700;
  color:var(--warn); background:var(--warn-bg); border:1px solid var(--warn-border);
  padding:1px 5px; border-radius:999px; text-transform:uppercase; letter-spacing:.03em; vertical-align:middle;
}

label.field-label{display:block; font-size:11.5px; font-weight:700; color:var(--ink-dim); margin:14px 0 6px; text-transform:uppercase; letter-spacing:.03em;}
textarea.remark-general{
  width:100%; border:1px solid var(--border); border-radius:9px; padding:9px 10px; font-size:13px;
  background:var(--surface-alt); color:var(--ink); resize:vertical; min-height:64px; font-family:inherit;
}
textarea.remark-general:focus{outline:2px solid var(--brand); outline-offset:1px; border-color:var(--brand);}

.btn{border:0; border-radius:9px; padding:11px 14px; font-weight:700; font-size:13.5px; cursor:pointer; width:100%;}
.btn-primary{background:var(--surface-alt); border:1px solid var(--border-strong); color:var(--ink);}
.btn-primary:hover{border-color:var(--brand); color:var(--brand-ink);}
.btn-success{background:var(--good); color:#fff;}
.btn-success:hover{filter:brightness(1.05);}
.btn-success:disabled{opacity:.5; cursor:not-allowed;}
.btn-ghost{background:transparent; border:1px solid var(--border); color:var(--ink-dim);}
.actions-row{display:flex; gap:8px;}
.shortcut-hint{
  margin-top:12px; padding-top:12px; border-top:1px dashed var(--border);
  font-size:11px; color:var(--ink-faint); display:flex; flex-wrap:wrap; gap:8px;
}
.shortcut-hint kbd{font-family:'JetBrains Mono'; background:var(--surface-alt); border:1px solid var(--border); border-radius:4px; padding:0 5px;}

/* ---------- Toasts & modal ---------- */
.toast-stack{position:fixed; right:16px; bottom:16px; display:flex; flex-direction:column; gap:8px; z-index:100;}
.toast{
  background:var(--surface); border:1px solid var(--border); color:var(--ink); box-shadow:var(--shadow);
  border-radius:10px; padding:10px 14px; font-size:13px; display:flex; align-items:center; gap:8px;
  animation: toast-in .18s ease-out; max-width:280px;
}
.toast.success{border-color:var(--good-border);}
.toast.error{border-color:var(--bad-border);}
.toast .dot{width:8px; height:8px; border-radius:50%; background:var(--good); flex:none;}
.toast.error .dot{background:var(--bad);}
@keyframes toast-in{from{opacity:0; transform:translateY(6px);} to{opacity:1; transform:translateY(0);}}

.modal-overlay{
  position:fixed; inset:0; background:rgba(6,12,24,.55); align-items:center; justify-content:center;
  z-index:200; padding:16px;
}
.modal-overlay:not([hidden]){display:flex;}
.modal{
  background:var(--surface); border:1px solid var(--border); border-radius:14px; padding:22px;
  max-width:360px; width:100%; box-shadow:var(--shadow);
}
.modal h3{font-size:16px; margin-bottom:8px;}
.modal p{font-size:13.5px; color:var(--ink-dim); line-height:1.5; margin:0 0 18px;}
.modal-actions{display:flex; gap:8px;}
.modal-actions .btn{width:auto; flex:1;}

.stamp-popover{
  position:fixed; z-index:150; background:var(--surface); border:1px solid var(--border);
  border-radius:10px; padding:8px; box-shadow:var(--shadow); gap:6px;
}
.stamp-popover:not([hidden]){display:flex;}
.stamp-popover input{
  border:1px solid var(--border); border-radius:6px; padding:6px 8px; font-size:13px;
  width:130px; background:var(--surface-alt); color:var(--ink);
}
.stamp-popover button{border:0; border-radius:6px; padding:6px 9px; font-size:12px; font-weight:700; cursor:pointer;}
.stamp-popover .pv-ok{background:var(--brand); color:#fff;}
.stamp-popover .pv-cancel{background:var(--surface-alt); color:var(--ink-dim); border:1px solid var(--border);}

@media (max-width:640px){
  .topbar{padding:10px 14px;}
  .crumb-script{font-size:15px;}
  .viewer-scroll{height:auto; flex-direction:column;}
  .thumbs{flex-direction:row; width:auto; overflow-x:auto;}
  .thumb{width:56px; height:74px;}
  .page-wrap{--page-width:100% !important;}
}