:root {
    --bg: #f6f7f9;
    --surface: #ffffff;
    --text: #1d2330;
    --muted: #5b6475;
    --line: #dde1e8;
    --accent: #1f5fbf;
    --good: #1c7c43;
    --bad: #b42318;
    --warn: #9a6700;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

.topbar {
    background: var(--surface);
    border-bottom: 1px solid var(--line);
    padding: 12px 16px;
}

.brand { color: var(--accent); font-weight: 600; text-decoration: none; }

.page { max-width: 960px; margin: 0 auto; padding: 24px 16px 48px; }

h1 { font-size: 1.6rem; margin: 0 0 8px; }
h2 { font-size: 1.1rem; margin: 0 0 8px; }

.lead { font-weight: 600; }
.good { color: var(--good); }
.bad { color: var(--bad); }
.warn { color: var(--warn); }
.mono { font-family: ui-monospace, Consolas, monospace; word-break: break-all; }

.checks {
    width: 100%;
    border-collapse: collapse;
    background: var(--surface);
    border: 1px solid var(--line);
    margin: 16px 0 24px;
}
.checks th, .checks td { padding: 8px 10px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.checks th { background: #eef1f5; font-size: .9rem; }
.checks td:last-child { color: var(--muted); font-size: .9rem; word-break: break-word; }

.cards { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 8px; padding: 16px; }
.qr svg { width: 200px; height: auto; }

@media (max-width: 600px) {
    .checks th:nth-child(3), .checks td:nth-child(3) { display: none; }
}

/* navigation */
.topbar { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
.nav { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; font-size: .95rem; }
.nav a { color: var(--accent); text-decoration: none; }
.nav .who { color: var(--muted); }
.inline { display: inline; margin: 0; }
button.link { background: none; border: 0; padding: 0; color: var(--accent); font: inherit; cursor: pointer; }

/* forms and messages */
.narrow { max-width: 420px; }
.form { display: grid; gap: 12px; margin: 16px 0; }
.form label { display: grid; gap: 4px; font-weight: 600; font-size: .95rem; }
.form input { font: inherit; padding: 9px 10px; border: 1px solid var(--line); border-radius: 6px; background: var(--surface); }
.form fieldset { border: 1px solid var(--line); border-radius: 8px; padding: 12px; display: grid; gap: 10px; background: var(--surface); }
.form legend { font-weight: 600; padding: 0 4px; }
.two-col { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); align-items: start; }
.two-col > button { grid-column: 1 / -1; justify-self: start; }
button.primary { font: inherit; font-weight: 600; background: var(--accent); color: #fff; border: 0; border-radius: 6px; padding: 10px 16px; cursor: pointer; }
.flash { border: 1px solid currentColor; border-radius: 6px; padding: 10px 12px; margin: 12px 0; background: var(--surface); }
.muted { color: var(--muted); font-weight: normal; }

/* setup steps */
.steps { list-style: none; padding: 0; display: grid; gap: 12px; }
.steps li { background: var(--surface); border: 1px solid var(--line); border-left: 4px solid var(--line); border-radius: 8px; padding: 12px 16px; }
.steps li.done { border-left-color: var(--good); }

/* subject page */
table.plain { width: 100%; border-collapse: collapse; }
table.plain td { padding: 4px 0; border-bottom: 1px solid var(--line); vertical-align: top; }
td.num { text-align: right; white-space: nowrap; padding-left: 12px; }
.tag { display: inline-block; font-size: .8rem; padding: 1px 6px; border-radius: 10px; background: #eef1f5; color: var(--muted); margin-left: 4px; }
.tag.bad { background: #fde8e7; color: var(--bad); }
details { margin: 12px 0; }
details.tree { background: var(--surface); border: 1px solid var(--line); border-radius: 8px; padding: 8px 14px; }
.chapter h3 { font-size: 1rem; margin: 12px 0 4px; }
.chapter ul { margin: 0 0 8px; padding-left: 20px; }
.constants { columns: 2 260px; }

/* wide tables scroll sideways on small screens instead of widening the page */
@media (max-width: 760px) {
    table.checks { display: block; overflow-x: auto; white-space: nowrap; }
    .mono { font-size: .85rem; }
}

/* question bank */
.question { margin: 16px 0; }
.qhead { display: flex; flex-wrap: wrap; gap: 4px; margin-bottom: 8px; }
.qhead .tag { margin-left: 0; }
.stem { margin: 6px 0; }
.options { list-style: none; padding: 0; margin: 8px 0; display: grid; gap: 4px; }
.options li { padding: 4px 8px; border: 1px solid var(--line); border-radius: 6px; }
.options li.correct { border-color: var(--good); background: #eaf6ee; }
.opt { font-weight: 600; margin-right: 6px; }
table.points { width: 100%; border-collapse: collapse; margin: 8px 0; font-size: .95rem; }
table.points th, table.points td { border: 1px solid var(--line); padding: 6px 8px; vertical-align: top; text-align: left; }
table.points th { background: #eef1f5; }
.alt { margin-top: 4px; font-size: .9rem; }
.part { border-left: 3px solid var(--line); padding-left: 10px; margin: 10px 0; }
.qmeta { border-top: 1px solid var(--line); margin-top: 10px; padding-top: 8px; font-size: .9rem; }
.qmeta .tag { margin: 2px 4px 2px 0; }
.pager { display: flex; gap: 16px; justify-content: center; margin: 20px 0; }

/* review screen */
.page:has(.review-grid) { max-width: 1500px; }
.review-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 12px; flex-wrap: wrap; }
.review-actions { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
button.small { font: inherit; font-size: .9rem; padding: 6px 10px; border: 1px solid var(--line); background: var(--surface); border-radius: 6px; cursor: pointer; }
button.danger { color: var(--bad); border-color: var(--bad); }
button.primary:disabled { opacity: .5; cursor: not-allowed; }
.review-grid { display: grid; gap: 16px; grid-template-columns: 1fr; }
@media (min-width: 1100px) {
    .review-grid { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); align-items: start; }
    .viewer { position: sticky; top: 8px; max-height: calc(100vh - 16px); overflow: auto; }
}
.viewer-bar { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-bottom: 8px; }
.page-no { width: 4em; }
.page-wrap { position: relative; border: 1px solid var(--line); line-height: 0; }
.page-wrap canvas { display: block; }
.page-wrap.cropping { cursor: crosshair; touch-action: none; }
.crop-box { position: absolute; border: 2px solid var(--accent); background: rgba(31, 95, 191, .12); pointer-events: none; }
.crop-panel { display: grid; gap: 8px; margin-bottom: 8px; padding: 8px; border: 1px dashed var(--accent); border-radius: 6px; }
.crop-panel label { display: grid; gap: 4px; font-size: .9rem; }
.figure-note { border-left: 3px solid var(--warn); padding: 4px 10px; margin: 8px 0; }
.figure-note.done { border-left-color: var(--good); opacity: .75; }
.media-list { display: flex; flex-wrap: wrap; gap: 12px; }
.media-list figure { margin: 0; max-width: 240px; }
.media-list img, .qfig img { max-width: 100%; border: 1px solid var(--line); background: #fff; }
.notes p { margin: 4px 0; font-size: .92rem; }
.review-form .row { display: flex; flex-wrap: wrap; gap: 12px; align-items: end; }
.review-form select, .review-form input[type=number] { font: inherit; padding: 6px; }
.review-form input[type=number] { width: 6em; }
.review-form textarea { font: 14px/1.4 ui-monospace, Consolas, monospace; width: 100%; padding: 6px; border: 1px solid var(--line); border-radius: 6px; }
.review-form fieldset { border: 1px solid var(--line); border-radius: 8px; padding: 10px; }
label.radio { display: inline-flex; gap: 4px; align-items: center; font-weight: normal; }
.opts { display: grid; gap: 6px; }
.opt-row { display: grid; grid-template-columns: 48px 1fr; gap: 6px; align-items: start; }
.point-row { border: 1px solid var(--line); border-radius: 6px; padding: 8px; margin: 6px 0; display: grid; gap: 6px; background: #fbfcfd; }
.point-meta { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.part-edit { margin: 10px 0; background: #fbfcfd; }
.part-edit h4 { margin: 8px 0 0; }
.preview { border-left: 3px solid var(--line); padding: 4px 8px; margin: 2px 0 6px; background: #fff; font: 15px/1.5 system-ui, sans-serif; }
.preview.has-error { border-left-color: var(--bad); }
.qfig { margin: 8px 0; max-width: 520px; }