/* Playable Pasts — shared styles.
   No framework, no build step. Light and dark from one token set. */

:root {
  --paper:      #faf8f4;
  --paper-sunk: #f2eee6;
  --card:       #ffffff;
  --ink:        #1e1b16;
  --ink-soft:   #57503f;
  /* --ink-faint is for small print. #6b6455 is 5.53:1 on --paper, 5.87:1 on
     --card, and 5.07:1 on --paper-sunk, so it meets the 4.5:1 minimum for text. */
  --ink-faint:  #6b6455;
  --rule:       #e2dbcc;
  /* Borders on things you click or type into. #8a8272 is 3.59:1 on --paper,
     3.81:1 on --card, and 3.29:1 on --paper-sunk (at least the 3:1 needed for
     a control's outline). --rule is decorative only. */
  --rule-strong:#8a8272;
  --rule-soft:  #eee9dd;
  --accent:     #8c2f24;
  --accent-soft:#f6e9e6;
  --block:      #a8321f;
  --block-bg:   #fdecea;
  --warn:       #8a5a00;
  --warn-bg:    #fbf1dc;
  --ok:         #2c6146;
  --ok-bg:      #e7f2eb;
  --manual:     #3f4f73;
  --manual-bg:  #eaeef7;

  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua",
           Georgia, "Songti TC", "Songti SC", serif;
  --sans:  system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue",
           "PingFang TC", "PingFang SC", "Microsoft JhengHei", "Hiragino Sans",
           "Noto Sans CJK TC", sans-serif;
  --mono:  ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;

  --measure: 34rem;
  --wide: 62rem;
  --radius: 4px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper:      #16150f;
    --paper-sunk: #1e1c15;
    --card:       #201e17;
    --ink:        #ece7d9;
    --ink-soft:   #b3ab98;
    /* 5.19:1 on --paper, 4.73:1 on --card, 4.84:1 on --paper-sunk. */
    --ink-faint:  #8f8878;
    --rule:       #35322a;
    /* 3.67:1 on --paper, 3.35:1 on --card, 3.42:1 on --paper-sunk. */
    --rule-strong:#737060;
    --rule-soft:  #2a2820;
    --accent:     #e8907f;
    --accent-soft:#31201c;
    --block:      #f0907f;
    --block-bg:   #33201c;
    --warn:       #e0b464;
    --warn-bg:    #2e2617;
    --ok:         #86c9a4;
    --ok-bg:      #1b2a21;
    --manual:     #9fb3dd;
    --manual-bg:  #1d2230;
  }
}

*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  /* Keep headings reached by a link or skip-link clear of the sticky masthead.
     Measured heights: about 56px on a wide screen, 87px when the menu wraps
     once, 122px on a phone. */
  scroll-padding-top: 4.5rem;
}
@media (max-width: 45rem) {
  html { scroll-padding-top: 6.5rem; }
}
@media (max-width: 35rem) {
  html { scroll-padding-top: 8.5rem; }
}

body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 17px/1.65 var(--sans);
  font-synthesis-weight: none;
}

/* ---------- layout ---------- */

.wrap {
  max-width: var(--wide);
  margin: 0 auto;
  padding-inline: 20px;
}

.prose { max-width: var(--measure); }

main { padding-block: 0 5rem; }

section { padding-block: 3rem; }
section + section { border-top: 1px solid var(--rule-soft); }

/* ---------- masthead ---------- */

.masthead {
  border-bottom: 1px solid var(--rule);
  background: var(--paper);
  position: sticky;
  top: 0;
  z-index: 20;
}

.masthead-inner {
  max-width: var(--wide);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  align-items: baseline;
}

.wordmark {
  font: 600 19px/1 var(--serif);
  letter-spacing: 0.01em;
  color: var(--ink);
  text-decoration: none;
  white-space: nowrap;
}
.wordmark span { color: var(--accent); }

.masthead nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
  margin-left: auto;
  font-size: 15px;
}
.masthead nav a {
  color: var(--ink-soft);
  text-decoration: none;
  padding: 2px 0;
  border-bottom: 2px solid transparent;
}
.masthead nav a:hover { color: var(--ink); border-bottom-color: var(--rule); }
.masthead nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--accent); }

/* ---------- type ---------- */

h1, h2, h3 { font-family: var(--serif); font-weight: 600; line-height: 1.2; }

h1 {
  font-size: clamp(2rem, 5.2vw, 3rem);
  margin: 0 0 1rem;
  letter-spacing: -0.015em;
}
h2 { font-size: 1.6rem; margin: 0 0 0.8rem; }
h3 { font-size: 1.18rem; margin: 0 0 0.4rem; font-family: var(--sans); font-weight: 650; }

.lede {
  font-size: 1.2rem;
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: var(--measure);
}

.eyebrow {
  font: 600 12px/1 var(--sans);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 1rem;
}

p { margin: 0 0 1rem; }
a { color: var(--accent); text-underline-offset: 2px; }

small, .small { font-size: 0.875rem; color: var(--ink-soft); }

code, kbd {
  font-family: var(--mono);
  font-size: 0.9em;
  background: var(--paper-sunk);
  border: 1px solid var(--rule-soft);
  border-radius: 3px;
  padding: 0.1em 0.35em;
}

kbd { font-size: 0.8em; box-shadow: 0 1px 0 var(--rule); }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font: 600 16px/1 var(--sans);
  padding: 12px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--accent);
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  cursor: pointer;
}
.btn:hover { filter: brightness(1.08); }
.btn.secondary {
  background: transparent;
  color: var(--ink);
  border-color: var(--rule-strong);
}
.btn.secondary:hover { background: var(--paper-sunk); filter: none; }
.btn.small { font-size: 14px; padding: 8px 14px; }

@media (prefers-color-scheme: dark) {
  /* Only the filled button flips to dark text; the outlined one keeps --ink,
     or it becomes dark-on-dark. */
  :root:not([data-theme="light"]) .btn:not(.secondary) { color: #201e17; }
}

.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin: 1.5rem 0; }

:where(a, button, summary, input, select, textarea, [tabindex]):focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ---------- cards & grids ---------- */

.grid { display: grid; gap: 20px; }
.grid.two   { grid-template-columns: repeat(auto-fit, minmax(min(100%, 20rem), 1fr)); }
.grid.three { grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr)); }

.card {
  background: var(--card);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: 20px;
}

.card h3 { margin-bottom: 0.35rem; }
.card p:last-child { margin-bottom: 0; }

/* numbered steps */
.steps { counter-reset: step; list-style: none; padding: 0; margin: 0; }
.steps > li {
  counter-increment: step;
  position: relative;
  padding-left: 3rem;
  padding-block: 0.6rem 1.4rem;
}
.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0.55rem;
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  font: 650 15px/1 var(--sans);
}
.steps h3 { margin-bottom: 0.25rem; }
.steps p { margin-bottom: 0.4rem; }

/* ---------- copy box ---------- */

.copybox {
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
  overflow: hidden;
}
.copybox header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  background: var(--paper-sunk);
  border-bottom: 1px solid var(--rule);
  font: 600 13px/1 var(--sans);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.copybox header button { margin-left: auto; }
.copybox pre {
  margin: 0;
  padding: 16px;
  font: 400 14px/1.6 var(--mono);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  color: var(--ink);
}

/* ---------- tables ---------- */

.table-scroll { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-size: 0.95rem; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--rule-soft); vertical-align: top; }
th { font: 650 13px/1.3 var(--sans); text-transform: uppercase; letter-spacing: 0.05em; color: var(--ink-soft); }

/* ---------- badges ---------- */

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font: 650 12px/1 var(--sans);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 5px 9px;
  border-radius: 999px;
  border: 1px solid currentColor;
}
.badge.block  { color: var(--block); background: var(--block-bg); }
.badge.warn   { color: var(--warn);  background: var(--warn-bg); }
.badge.ok     { color: var(--ok);    background: var(--ok-bg); }
.badge.manual { color: var(--manual); background: var(--manual-bg); }
.badge.quiet  { color: var(--ink-faint); background: transparent; border-color: var(--rule-strong); }

/* ---------- footer ---------- */

.site-footer {
  border-top: 1px solid var(--rule);
  padding-block: 2rem 3rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
}
.site-footer a { color: var(--ink-soft); }
.site-footer .cols {
  display: grid;
  gap: 20px;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 14rem), 1fr));
}

/* ---------- misc ---------- */

hr { border: 0; border-top: 1px solid var(--rule); margin: 2rem 0; }

.skip-link {
  position: absolute;
  left: -9999px;
}
.skip-link:focus {
  left: 20px;
  top: 8px;
  z-index: 50;
  background: var(--card);
  padding: 10px 14px;
  border: 1px solid var(--accent);
  border-radius: var(--radius);
}

.note {
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  padding: 14px 18px;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 1.5rem 0;
}
.note p:last-child { margin-bottom: 0; }
.note strong { color: var(--ink); }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* ================================================================== *
 * The checker page
 * ================================================================== */

.dropzone {
  border: 2px dashed var(--rule);
  border-radius: 8px;
  background: var(--card);
  padding: 3rem 1.5rem;
  text-align: center;
}
.dropzone.dragging { border-color: var(--accent); background: var(--accent-soft); }
.dropzone h2 { margin-bottom: 0.4rem; }
.dropzone p { color: var(--ink-soft); max-width: 30rem; margin-inline: auto; }
.dropzone input[type="file"] { position: absolute; left: -9999px; }
.dropzone label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font: 600 16px/1 var(--sans);
  padding: 12px 20px;
  border-radius: var(--radius);
  background: var(--accent);
  color: #fff;
  cursor: pointer;
  margin-top: 1.2rem;
}
.dropzone input[type="file"]:focus-visible + label {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .dropzone label { color: #201e17; }
}

.privacy-line {
  display: flex;
  gap: 8px;
  align-items: baseline;
  justify-content: center;
  margin-top: 1.5rem;
  font-size: 0.875rem;
  color: var(--ink-faint);
}

.verdict {
  border: 1px solid var(--rule);
  border-left-width: 5px;
  border-radius: var(--radius);
  background: var(--card);
  padding: 24px;
  margin-bottom: 2rem;
}
.verdict.block { border-left-color: var(--block); }
.verdict.warn  { border-left-color: var(--warn); }
.verdict.ok    { border-left-color: var(--ok); }
.verdict h2 { margin-bottom: 0.5rem; }
.verdict p { max-width: var(--measure); }
.verdict-file { color: var(--ink-faint); font-size: 0.9rem; }
.tally { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 1.2rem; }

.report-section { padding-block: 2rem; border-top: 1px solid var(--rule-soft); }
.report-section > h2 { display: flex; align-items: baseline; gap: 10px; }
.report-section .count {
  font: 650 13px/1 var(--sans);
  color: var(--ink-faint);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 5px 9px;
}

.finding {
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
  padding: 18px 20px;
  margin-bottom: 14px;
}
.finding > header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 0.6rem;
}
.finding > header h3 { margin: 0; }
.finding-body { max-width: var(--measure); }
.finding-body p { margin-bottom: 0.7rem; }
.finding .fix {
  border-left: 3px solid var(--rule);
  padding-left: 12px;
  color: var(--ink-soft);
  font-style: italic;
}

.evidence {
  list-style: none;
  margin: 0.8rem 0 0;
  padding: 12px 14px;
  background: var(--paper-sunk);
  border-radius: var(--radius);
  font-size: 0.9rem;
}
.evidence li + li { margin-top: 6px; }
.evidence code { background: transparent; border: 0; padding: 0; overflow-wrap: anywhere; }
.lineno { color: var(--ink-faint); font-variant-numeric: tabular-nums; }

.manual-list { counter-reset: mc; list-style: none; padding: 0; margin: 1.5rem 0 0; }
.manual-list > li {
  counter-increment: mc;
  border-top: 1px solid var(--rule-soft);
  padding: 1rem 0 1rem 3rem;
  position: relative;
  max-width: var(--measure);
}
.manual-list > li::before {
  content: counter(mc);
  position: absolute;
  left: 0;
  top: 1rem;
  width: 2rem; height: 2rem;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--manual-bg);
  color: var(--manual);
  font: 650 14px/1 var(--sans);
}
.manual-list h3 { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.manual-list p { margin: 0.3rem 0 0; color: var(--ink-soft); }

#live-panel { padding-block: 2rem; border-top: 1px solid var(--rule-soft); }
.live-frame {
  width: 100%;
  height: 380px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: #fff;
}
#live-stage:empty { display: none; }
#live-stage { margin-top: 1.2rem; }

/* ================================================================== *
 * The gallery
 * ================================================================== */

.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  padding-block: 1.2rem;
  border-bottom: 1px solid var(--rule-soft);
}
.filters label { font-size: 0.875rem; color: var(--ink-soft); }
.filters select, .filters input[type="search"] {
  font: 400 15px/1 var(--sans);
  padding: 9px 11px;
  border: 1px solid var(--rule-strong);
  border-radius: var(--radius);
  background: var(--card);
  color: var(--ink);
}
.filters input[type="search"] { min-width: 14rem; }

.game-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 19rem), 1fr));
  padding-block: 2rem;
  list-style: none;
  margin: 0;
  padding-inline: 0;
}

.game-card {
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.game-card .thumb {
  aspect-ratio: 16 / 9;
  background: var(--paper-sunk);
  display: grid;
  place-items: center;
  font-size: 2.6rem;
  border-bottom: 1px solid var(--rule-soft);
}
.game-card .body { padding: 16px 18px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.game-card h2 { margin: 0; font-family: var(--serif); font-size: 1.2rem; font-weight: 600; }
.game-card h2 a { color: var(--ink); text-decoration: none; }
.game-card h2 a:hover { color: var(--accent); }
.game-card .meta { font-size: 0.82rem; color: var(--ink-faint); }
.game-card .desc { font-size: 0.93rem; color: var(--ink-soft); margin: 0; }
.game-card .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: auto; padding-top: 6px; }
.tag {
  font: 500 12px/1 var(--sans);
  padding: 5px 8px;
  border-radius: 3px;
  background: var(--paper-sunk);
  color: var(--ink-soft);
  border: 1px solid var(--rule-soft);
}

.empty-state {
  border: 1px dashed var(--rule);
  border-radius: var(--radius);
  padding: 3rem 1.5rem;
  text-align: center;
  color: var(--ink-soft);
}

/* ================================================================== *
 * A single game's page
 * ================================================================== */

.game-header { padding-block: 2.5rem 1.5rem; }
.game-header h1 { margin-bottom: 0.5rem; }
.game-meta { display: flex; flex-wrap: wrap; gap: 8px 16px; font-size: 0.9rem; color: var(--ink-soft); }

.play-frame {
  width: 100%;
  height: min(76vh, 640px);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: #fff;
}

.tabs { display: flex; flex-wrap: wrap; gap: 2px; border-bottom: 1px solid var(--rule); margin-top: 2rem; }
.tabs button {
  font: 600 15px/1 var(--sans);
  padding: 12px 16px;
  border: 0;
  border-bottom: 2px solid transparent;
  background: transparent;
  color: var(--ink-soft);
  cursor: pointer;
}
.tabs button[aria-selected="true"] { color: var(--ink); border-bottom-color: var(--accent); }
.tabpanel { padding-block: 1.8rem; }
.tabpanel[hidden] { display: none; }

.ledger td:first-child { font-family: var(--mono); font-size: 0.85rem; white-space: nowrap; }

/* ================================================================== *
 * Printing
 *
 * A printed game page should carry the teacher guide, the sources, and the
 * test ledger, not a blank frame and a row of tabs.
 * ================================================================== */

@media print {
  .masthead, .skip-link, .tabs, .play-frame, .btn-row, .copybox button,
  .site-footer .cols > div:has(> a) { display: none !important; }
  .tabpanel, .tabpanel[hidden] { display: block !important; }
  body { background: #fff; color: #000; }
  section, .tabpanel { break-inside: auto; }
  .tabpanel + .tabpanel { border-top: 1px solid #999; }
}