/* Grading Console — quiet institutional styling.
 * Tokens first; components below. No gradients, no heavy shadows. */
:root {
  --bg: #f6f4ee;
  --surface: #fbfaf7;
  --surface-2: #f1eee6;
  --ink: #1e2124;
  --ink-2: #4a4f57;
  --ink-3: #767b83;
  --rule: #e2ded3;
  --rule-2: #cfc9ba;
  --navy: #1d3f94;        /* royal blue, from the logo wordmark */
  --navy-2: #2a52b3;
  --navy-soft: #e6ecf8;
  --band-a: #1d3f94;
  --band-b: #8ea3d4;
  --sage: #4f6f53;
  --sage-soft: #e5ece3;
  --amber: #8a5a00;        /* gold family, darkened for legible text */
  --amber-soft: #f8ebcc;
  --red: #b3202d;          /* crimson, from the logo */
  --red-soft: #f7e1e2;
  --focus: #2a52b3;
  --crimson: #b3202d;
  --gold: #e8a916;         /* logo gold — fills and accents only, never text */

  --sans: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --serif: "Source Serif 4", Georgia, "Times New Roman", serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;

  --r: 4px;
  --gutter: 16px;
  color-scheme: light;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 400 14px/1.55 var(--sans);
  font-feature-settings: "cv11", "ss01";
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
h1, h2, h3 { margin: 0; font-weight: 600; }
p { margin: 0; }
button, input, select { font: inherit; color: inherit; }
.num, table, .metric__value, input[type="number"] { font-variant-numeric: tabular-nums lining-nums; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }
[hidden] { display: none !important; }

.skip { position: absolute; left: -999px; top: 8px; background: var(--ink); color: var(--bg); padding: 6px 10px; z-index: 10; }
.skip:focus { left: 8px; }

.wrap { max-width: 1240px; margin: 0 auto; padding: 0 var(--gutter); }
@media (min-width: 720px) { :root { --gutter: 28px; } }

/* ---------- Masthead ---------- */
.masthead { border-bottom: 1px solid var(--rule); background: var(--bg); }
/* Thin three-colour rule drawn from the logo palette. */
.masthead::before { content: ""; display: block; height: 3px; background: linear-gradient(90deg, var(--navy) 0 70%, var(--crimson) 70% 88%, var(--gold) 88% 100%); }
.masthead__inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 56px; }
.brand { display: flex; align-items: center; gap: 10px; min-width: 0; }
.brand__mark { width: 18px; height: 18px; border-bottom: 1.5px solid var(--navy); background:
  linear-gradient(var(--navy), var(--navy)) 2px 100% / 4px 80% no-repeat,
  linear-gradient(var(--crimson), var(--crimson)) 7px 100% / 4px 55% no-repeat,
  linear-gradient(var(--gold), var(--gold)) 12px 100% / 4px 32% no-repeat; }
.brand__name { font: 600 15px/1 var(--sans); letter-spacing: -0.005em; color: var(--navy); }
.brand__tag { font-size: 11px; letter-spacing: .06em; text-transform: uppercase; color: var(--ink-3); border: 1px solid var(--rule-2); padding: 2px 6px; border-radius: 2px; }
.masthead__file { font-size: 13px; color: var(--ink-2); display: flex; align-items: center; gap: 10px; min-width: 0; }
@media (max-width: 600px) { .masthead__file .fname, .masthead__file .muted { display: none; } .brand__tag { display: none; } }
.masthead__file .fname { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 32ch; }

/* ---------- Steps ---------- */
.steps { border-bottom: 1px solid var(--rule); background: var(--bg); position: sticky; top: 0; z-index: 5; }
.steps__list { list-style: none; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); margin: 0 auto; }
.step { min-width: 0; }
.step button {
  all: unset; box-sizing: border-box; display: flex; align-items: baseline; gap: 10px; width: 100%;
  padding: 14px 12px 12px 0; cursor: pointer; border-bottom: 2px solid transparent; margin-bottom: -1px;
}
.step button:focus-visible { outline: 2px solid var(--focus); outline-offset: -2px; }
.step__n { font: 500 12px/1 var(--sans); color: var(--ink-3); letter-spacing: .04em; }
.step__label { font-weight: 600; color: var(--ink-2); white-space: nowrap; }
.step__state { margin-left: 4px; font-size: 12px; color: var(--ink-3); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.step[aria-current="step"] button { border-bottom-color: var(--navy); }
.step[aria-current="step"] .step__n { color: var(--crimson); }
.step[aria-current="step"] .step__label { color: var(--ink); }
.step.is-locked button { cursor: not-allowed; }
.step.is-locked .step__label, .step.is-locked .step__n { color: #aeb1b5; }
.step .state-ok { color: var(--sage); }
.step .state-warn { color: var(--amber); }
.step .state-err { color: var(--red); }
@media (max-width: 720px) {
  .step button { flex-direction: column; gap: 2px; padding: 10px 6px 8px 0; }
  .step__state { margin-left: 0; font-size: 11px; }
  .step__label { font-size: 13px; }
}

/* ---------- Layout ---------- */
.layout { display: grid; grid-template-columns: 1fr; gap: 28px; padding-top: 28px; padding-bottom: 48px; flex: 1; width: 100%; }
.layout.has-rail { grid-template-columns: 232px minmax(0, 1fr); }
.stage { min-width: 0; outline: none; }
@media (max-width: 900px) { .layout.has-rail { grid-template-columns: minmax(0, 1fr); } }

/* ---------- Course rail ---------- */
.rail { position: sticky; top: 72px; align-self: start; max-height: calc(100vh - 96px); display: flex; flex-direction: column; min-width: 0; }
.rail__head { display: flex; justify-content: space-between; align-items: baseline; padding-bottom: 8px; border-bottom: 1px solid var(--rule); }
.rail__list { list-style: none; margin: 0; padding: 0; overflow-y: auto; }
.rail__item button {
  all: unset; box-sizing: border-box; display: grid; grid-template-columns: 1fr auto; gap: 2px 8px; width: 100%;
  padding: 9px 10px; border-left: 2px solid transparent; cursor: pointer; border-bottom: 1px solid var(--rule);
}
.rail__item button:hover { background: var(--surface-2); }
.rail__item button:focus-visible { outline: 2px solid var(--focus); outline-offset: -2px; }
.rail__item[aria-current="true"] button { border-left-color: var(--navy); background: var(--surface); }
.rail__name { font-weight: 500; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.rail__count { font-size: 12px; color: var(--ink-3); }
.rail__meta { grid-column: 1 / -1; font-size: 12px; color: var(--ink-3); display: flex; gap: 8px; }
.rail__select { display: none; }
@media (max-width: 900px) {
  .rail { position: static; max-height: none; }
  .rail__list { display: none; }
  .rail__select { display: block; }
  .rail__head { border: 0; padding-bottom: 6px; }
}

/* ---------- Type ---------- */
.eyebrow { font: 500 11px/1.2 var(--sans); letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }
.head .eyebrow { color: var(--crimson); }
.display { font: 600 30px/1.15 var(--serif); letter-spacing: -0.01em; margin-top: 6px; color: var(--navy); }
.lede { color: var(--ink-2); margin-top: 8px; max-width: 64ch; }
.section-title { font: 600 18px/1.3 var(--serif); }
.muted { color: var(--ink-3); }
.small { font-size: 12.5px; }
.mono { font-family: var(--mono); font-size: 12.5px; }
.head { display: flex; justify-content: space-between; align-items: flex-end; gap: 16px; flex-wrap: wrap; margin-bottom: 24px; }

/* ---------- Surfaces ---------- */
.panel { background: var(--surface); border: 1px solid var(--rule); border-radius: var(--r); padding: 20px; min-width: 0; }
.panel + .panel { margin-top: 16px; }
.panel__head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; margin-bottom: 14px; flex-wrap: wrap; }
.grid-2 { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); gap: 16px; }
.grid-2 > .panel + .panel { margin-top: 0; }
@media (max-width: 1000px) { .grid-2 { grid-template-columns: minmax(0, 1fr); } }
.stack > * + * { margin-top: 16px; }
hr.rule { border: 0; border-top: 1px solid var(--rule); margin: 16px 0; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px; height: 36px; padding: 0 14px; border-radius: var(--r);
  border: 1px solid var(--rule-2); background: var(--surface); color: var(--ink); font-weight: 500; cursor: pointer; white-space: nowrap;
  text-decoration: none;
}
.btn:hover { background: var(--surface-2); }
.btn--primary { background: var(--navy); border-color: var(--navy); color: #fbfaf7; }
.btn--primary:hover { background: var(--navy-2); border-color: var(--navy-2); }
.btn--quiet { border-color: transparent; background: transparent; color: var(--navy); padding: 0 8px; }
.btn--quiet:hover { background: var(--navy-soft); }
.btn:disabled, .btn[aria-disabled="true"] { opacity: .45; cursor: not-allowed; }
.btn--lg { height: 44px; padding: 0 20px; font-size: 15px; }
.actions { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }

/* ---------- Form ---------- */
.field { display: grid; gap: 6px; }
.field label { font-size: 12.5px; font-weight: 500; color: var(--ink-2); }
.input, .select {
  height: 36px; padding: 0 10px; border: 1px solid var(--rule-2); border-radius: var(--r); background: #fff; min-width: 0; width: 100%;
}
.input:focus, .select:focus { outline: 2px solid var(--focus); outline-offset: -1px; border-color: var(--focus); }
.check { display: flex; gap: 10px; align-items: flex-start; cursor: pointer; }
.check input { margin: 3px 0 0; accent-color: var(--navy); width: 16px; height: 16px; flex: none; }
.switch { display: inline-flex; gap: 8px; align-items: center; font-size: 13px; color: var(--ink-2); cursor: pointer; }
.switch input { accent-color: var(--navy); width: 16px; height: 16px; margin: 0; }

/* ---------- Import ---------- */
.drop {
  display: grid; place-items: center; text-align: center; gap: 10px; min-height: 260px; padding: 28px 20px;
  border: 1.5px dashed var(--rule-2); border-radius: var(--r); background: var(--surface); cursor: pointer; transition: background .15s, border-color .15s;
}
.drop:hover, .drop.is-over { border-color: var(--navy); background: var(--navy-soft); }
.drop:focus-within { outline: 2px solid var(--focus); outline-offset: 2px; }
.drop__icon { width: 36px; height: 44px; border: 1.5px solid var(--ink-3); border-radius: 2px; position: relative; margin: 0 auto; }
.drop__icon::after { content: "XLSX"; position: absolute; left: 50%; bottom: 6px; transform: translateX(-50%); font: 600 8px/1 var(--sans); letter-spacing: .06em; color: var(--ink-3); }
.drop__title { font: 600 18px/1.3 var(--serif); }
.drop input[type="file"] { position: absolute; width: 1px; height: 1px; opacity: 0; pointer-events: none; }
.progress { height: 3px; background: var(--rule); border-radius: 2px; overflow: hidden; width: min(280px, 80%); margin: 6px auto 0; }
.progress > span { display: block; height: 100%; background: var(--navy); width: 0; transition: width .15s; }

.spec { width: 100%; border-collapse: collapse; font-size: 13px; }
.spec th, .spec td { text-align: left; padding: 7px 10px 7px 0; border-bottom: 1px solid var(--rule); }
.spec th { font-weight: 500; color: var(--ink-2); }
.spec td.num, .spec th.num { text-align: right; padding-right: 0; }
.rules { margin: 14px 0 0; padding: 0; list-style: none; display: grid; gap: 8px; font-size: 13px; color: var(--ink-2); }
.rules li { padding-left: 16px; position: relative; }
.rules li::before { content: ""; position: absolute; left: 0; top: .7em; width: 6px; height: 1px; background: var(--ink-3); }

/* ---------- Callouts ---------- */
.callout { border: 1px solid var(--rule); border-left-width: 3px; border-radius: var(--r); padding: 14px 16px; background: var(--surface); }
.callout__title { font-weight: 600; }
.callout--ok { border-left-color: var(--sage); }
.callout--ok .callout__title { color: var(--sage); }
.callout--warn { border-left-color: var(--amber); background: #fbf6ec; }
.callout--warn .callout__title { color: var(--amber); }
.callout--err { border-left-color: var(--red); background: #fbf1ef; }
.callout--err .callout__title { color: var(--red); }
.callout p + p, .callout__title + p, .callout__title + ul { margin-top: 4px; }
.callout ul { margin: 6px 0 0; padding-left: 18px; }

.result__line { font: 600 26px/1.2 var(--serif); margin-top: 4px; }
.result__line .sep { color: var(--rule-2); margin: 0 .35em; font-weight: 400; }

/* ---------- Metrics ---------- */
.metrics { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); border-top: 1px solid var(--ink); }
.metric { padding: 12px 12px 4px 0; min-width: 0; }
.metric + .metric { padding-left: 12px; border-left: 1px solid var(--rule); }
.metric__label { font-size: 12px; color: var(--ink-3); }
.metric__value { font: 500 26px/1.2 var(--sans); letter-spacing: -0.02em; margin-top: 4px; }
.metric__sub { font-size: 12px; color: var(--ink-3); }
@media (max-width: 1000px) {
  .metrics { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .metric:nth-child(4) { padding-left: 0; border-left: 0; }
  .metric:nth-child(n+4) { border-top: 1px solid var(--rule); }
}
@media (max-width: 480px) { .metric__value { font-size: 21px; } }

.quality { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 0; border: 1px solid var(--rule); border-radius: var(--r); overflow: hidden; }
.quality > div { padding: 12px 14px; background: var(--surface); min-width: 0; }
.quality > div + div { border-left: 1px solid var(--rule); }
.quality .q__n { font: 500 20px/1.2 var(--sans); }
.quality .q__l { font-size: 12px; color: var(--ink-3); }
.quality .is-bad .q__n { color: var(--amber); }
.quality .is-good .q__n { color: var(--sage); }
@media (max-width: 640px) {
  .quality { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .quality > div:nth-child(3) { border-left: 0; }
  .quality > div:nth-child(n+3) { border-top: 1px solid var(--rule); }
}

/* ---------- Tables ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--rule); border-radius: var(--r); background: var(--surface); }
.table { width: 100%; border-collapse: collapse; font-size: 13px; }
.table th, .table td { padding: 8px 12px; text-align: left; border-bottom: 1px solid var(--rule); white-space: nowrap; }
.table thead th { font-weight: 500; color: var(--ink-2); background: var(--surface-2); position: sticky; top: 0; }
.table tbody tr:last-child td { border-bottom: 0; }
.table .num { text-align: right; }
.table td.wrap-ok { white-space: normal; }
.table--scroll { max-height: 420px; overflow-y: auto; }
.tag { display: inline-block; font-size: 12px; padding: 1px 7px; border-radius: 2px; background: var(--surface-2); color: var(--ink-2); }
.tag--warn { background: var(--amber-soft); color: var(--amber); }
.tag--ok { background: var(--sage-soft); color: var(--sage); }
.tag--err { background: var(--red-soft); color: var(--red); }
.dot { width: 7px; height: 7px; border-radius: 50%; display: inline-block; background: var(--ink-3); vertical-align: middle; }
.dot--ok { background: var(--sage); }
.dot--warn { background: var(--amber); }
.dot--err { background: var(--red); }

details.disclose > summary { cursor: pointer; list-style: none; display: flex; align-items: center; gap: 8px; font-weight: 500; }
details.disclose > summary::-webkit-details-marker { display: none; }
details.disclose > summary::before { content: ""; width: 6px; height: 6px; border-right: 1.5px solid var(--ink-2); border-bottom: 1.5px solid var(--ink-2); transform: rotate(-45deg); transition: transform .15s; }
details.disclose[open] > summary::before { transform: rotate(45deg); }

/* ---------- Charts ---------- */
.chart { width: 100%; height: auto; display: block; overflow: visible; }
.chart text { font: 11px var(--sans); fill: var(--ink-3); font-variant-numeric: tabular-nums; }
.chart .axis { stroke: var(--ink); stroke-width: 1; }
.chart .grid { stroke: var(--rule); stroke-width: 1; }
.chart .bar { fill: var(--navy); }
.chart .bar:hover { fill: var(--navy-2); }
.chart .val { fill: var(--ink-2); font-weight: 500; }
.chart .marker { stroke: var(--ink); stroke-width: 1; stroke-dasharray: 3 3; }
.chart .marker-label { fill: var(--ink); font-weight: 500; }
.chart .band-bg-0 { fill: var(--surface-2); }
.chart .band-bg-1 { fill: transparent; }
.chart .band-bar-0 { fill: var(--band-a); }
.chart .band-bar-1 { fill: var(--band-b); }
.chart .cut { stroke: var(--ink); stroke-width: 1; }
.chart .grade-label { fill: var(--ink); font-weight: 600; font-size: 12px; }
.chart .bad { fill: var(--red-soft); }
.legend { display: flex; gap: 16px; flex-wrap: wrap; font-size: 12px; color: var(--ink-3); margin-top: 8px; }
.legend i { display: inline-block; width: 14px; height: 0; border-top: 1px dashed var(--ink); vertical-align: middle; margin-right: 6px; }

.insights { list-style: none; margin: 0; padding: 0; }
.insights li { padding: 10px 0; border-bottom: 1px solid var(--rule); color: var(--ink-2); }
.insights li:first-child { padding-top: 0; }
.insights li:last-child { border-bottom: 0; padding-bottom: 0; }

/* ---------- Grade editor ---------- */
.bands { width: 100%; border-collapse: collapse; }
.bands th { font-size: 12px; font-weight: 500; color: var(--ink-3); text-align: left; padding: 0 8px 8px 0; border-bottom: 1px solid var(--ink); }
.bands td { padding: 6px 8px 6px 0; border-bottom: 1px solid var(--rule); vertical-align: middle; }
.bands .g { font: 600 16px/1 var(--serif); width: 44px; }
.bands .to { color: var(--ink-3); padding: 0 6px 0 0; width: 14px; text-align: center; }
.bands input[type="number"] {
  width: 64px; height: 34px; padding: 0 8px; text-align: right; border: 1px solid var(--rule-2); border-radius: var(--r); background: #fff;
  -moz-appearance: textfield; appearance: textfield;
}
.bands input[type="number"]::-webkit-inner-spin-button { opacity: 1; }
.bands input.is-invalid { border-color: var(--red); background: #fbf1ef; color: var(--red); }
.bands input.is-fixed { background: var(--surface-2); color: var(--ink-2); }
.bands .cnt { text-align: right; width: 48px; font-weight: 500; }
.bands .pct { text-align: right; width: 48px; color: var(--ink-3); font-size: 12.5px; }
.bands .barcell { width: 36%; padding-right: 0; }
.bands .hbar { height: 10px; background: var(--navy); border-radius: 1px; min-width: 0; transition: width .2s; }
.bands .hbar.is-zero { background: transparent; border-left: 1px solid var(--rule-2); height: 10px; }
.bands tr.is-bad td.g { color: var(--red); }
@media (max-width: 560px) {
  .bands .barcell, .bands th.barcell { display: none; }
  .bands input[type="number"] { width: 60px; padding: 0 6px; }
  .bands input[type="number"]::-webkit-inner-spin-button { display: none; }
}

.status { display: flex; gap: 10px; align-items: baseline; padding: 12px 14px; border-radius: var(--r); border: 1px solid var(--rule); background: var(--surface); }
.status--ok { border-color: #c9d6c6; background: var(--sage-soft); color: var(--sage); }
.status--err { border-color: #e2c3bd; background: var(--red-soft); color: var(--red); }
.status ul { margin: 4px 0 0; padding-left: 18px; color: var(--ink); }
.status strong { font-weight: 600; }

/* ---------- Export ---------- */
.checklist { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--ink); }
.checklist li { display: grid; grid-template-columns: 22px minmax(0, 1fr) auto; gap: 10px; align-items: baseline; padding: 11px 0; border-bottom: 1px solid var(--rule); }
.checklist .k { color: var(--ink-2); }
.checklist .v { font-weight: 500; text-align: right; }
.checklist .ico { font-size: 13px; text-align: center; }
.ico-ok { color: var(--sage); }
.ico-warn { color: var(--amber); }
.ico-err { color: var(--red); }
.ico-info { color: var(--ink-3); }
.ready { font: 600 13px/1 var(--sans); letter-spacing: .08em; text-transform: uppercase; }
.ready--ok { color: var(--sage); }
.ready--no { color: var(--amber); }
.preview { font: 12px/1.6 var(--mono); background: var(--surface-2); border: 1px solid var(--rule); border-radius: var(--r); padding: 12px 14px; overflow-x: auto; white-space: pre; margin: 0; color: var(--ink-2); }

/* ---------- Toast ---------- */
.toast {
  position: fixed; left: 50%; bottom: 20px; transform: translateX(-50%); z-index: 20; max-width: calc(100vw - 32px);
  background: var(--ink); color: #f6f4ee; padding: 10px 12px 10px 16px; border-radius: var(--r); display: flex; gap: 14px; align-items: center; font-size: 13.5px;
}
.toast button { all: unset; cursor: pointer; font-weight: 600; color: #c9d7ea; padding: 4px 6px; border-radius: 2px; }
.toast button:focus-visible { outline: 2px solid #c9d7ea; }

/* ---------- Footer ---------- */
.footer { border-top: 1px solid var(--rule); padding: 16px 0 24px; font-size: 12px; color: var(--ink-3); }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}
@media print {
  .masthead, .steps, .rail, .footer, .toast, .actions { display: none !important; }
  body { background: #fff; }
}