:root {
  --ground:      #F4F5F1;
  --panel:       #FBFBF9;
  --ink:         #171A1D;
  --muted:       #5C646E;
  --rule:        #D8DAD3;
  --rule-soft:   #E7E8E2;
  --accent:      #B8480A;
  --accent-soft: #FBEADF;
  --mark:        #A9432A;
  --ok:          #2F6B3A;
  --ok-soft:     #E5F0E6;
  --shadow:      0 1px 0 rgba(23,26,29,.04);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font-family: "Source Serif 4", Georgia, "Times New Roman", "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", serif;
  font-size: 16.5px;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
}

.wrap { max-width: 60rem; margin: 0 auto; padding: 4.2rem 1.5rem 5rem; }

.t[lang="zh"], .t[lang="ja"], .t[lang="id"] { display: none; }
:root[data-lang="zh"] .t[lang="en"] { display: none; }
:root[data-lang="zh"] .t[lang="zh"] { display: inline; }
:root[data-lang="ja"] .t[lang="en"] { display: none; }
:root[data-lang="ja"] .t[lang="ja"] { display: inline; }
:root[data-lang="id"] .t[lang="en"] { display: none; }
:root[data-lang="id"] .t[lang="id"] { display: inline; }
:root[data-lang="zh"] body, :root[data-lang="ja"] body { line-height: 1.78; }
:root[data-lang="ja"] body { font-family: "Hiragino Sans", "Noto Sans JP", "Yu Gothic UI", "Meiryo", sans-serif; }
:root[data-lang="zh"] body { font-family: "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", sans-serif; }

.sans { font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif; }
.mono { font-family: "JetBrains Mono", ui-monospace, Consolas, monospace; }

/* ---------- fixed chrome ---------- */

.langbar {
  position: fixed; top: .7rem; right: .7rem; z-index: 50;
  display: flex; gap: 1px; padding: 2px;
  background: var(--panel); border: 1px solid var(--rule); border-radius: 3px;
  box-shadow: 0 1px 5px rgba(0,0,0,.13);
}

.langbtn {
  appearance: none; border: 0; border-radius: 2px; background: transparent;
  color: var(--muted);
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-weight: 600; font-size: .72rem; line-height: 1.35; padding: .3rem .55rem; cursor: pointer;
}
.langbtn:hover { color: var(--ink); }
.langbtn[aria-pressed="true"] { background: var(--accent); color: var(--ground); }

.countdown {
  position: fixed; top: .7rem; left: .7rem; z-index: 50;
  display: flex; align-items: baseline; gap: .4rem;
  padding: .35rem .7rem .35rem .6rem;
  background: var(--panel); border: 1px solid var(--rule); border-left: 3px solid var(--ok);
  border-radius: 3px; box-shadow: 0 1px 5px rgba(0,0,0,.13);
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-size: .78rem; color: var(--muted); line-height: 1.3;
}
.countdown b {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-weight: 500; font-size: 1.25rem; color: var(--ink); font-variant-numeric: tabular-nums;
}
.countdown .cd-date {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: .66rem; letter-spacing: .06em; text-transform: uppercase;
  padding-left: .5rem; border-left: 1px solid var(--rule-soft);
}
.countdown.soon { border-left-color: var(--accent); }
.countdown.soon b { color: var(--accent); }
.countdown.closed { border-left-color: var(--mark); }
.countdown.closed b, .countdown.closed .cd-label { color: var(--mark); }

@media (max-width: 40rem) {
  .countdown .cd-date { display: none; }
  .wrap { padding-top: 3.6rem; }
}

/* ---------- page ---------- */

.back {
  display: inline-block;
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: .7rem; letter-spacing: .12em; text-transform: uppercase;
  color: var(--muted); text-decoration: none; margin-bottom: 1.6rem;
}
.back:hover { color: var(--accent); }

.eyebrow {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: .705rem; letter-spacing: .14em; text-transform: uppercase;
  color: var(--muted); margin: 0 0 .8rem;
}

h1 {
  font-family: Archivo, "Helvetica Neue", Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-weight: 700; font-size: clamp(1.9rem, 4.8vw, 2.6rem);
  letter-spacing: -.024em; line-height: 1.05; margin: 0 0 .7rem;
}

.lede { max-width: 38em; color: var(--muted); font-size: 1.02rem; margin: 0 0 1.8rem; }
.lede b { color: var(--ink); font-weight: 600; }

.cards { display: grid; gap: 1.2rem; grid-template-columns: repeat(auto-fit, minmax(19rem, 1fr)); max-width: 60rem; }

.card {
  background: var(--panel); border: 1px solid var(--rule);
  padding: 1.5rem 1.6rem; box-shadow: var(--shadow); min-width: 0;
}
.card h2 {
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-weight: 600; font-size: 1.2rem; margin: 0 0 .35rem;
}
.card > p { color: var(--muted); font-size: .95rem; margin: 0 0 1.2rem; }
.card.wide { max-width: none; }

.field { display: grid; gap: .3rem; margin-bottom: .9rem; }
.field > span {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-size: .65rem; letter-spacing: .12em; text-transform: uppercase; color: var(--muted);
}
.field input {
  font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .88rem;
  padding: .5rem .6rem; border: 1px solid var(--rule); border-radius: 2px;
  background: var(--ground); color: var(--ink); width: 100%;
}
.field input:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.field .hint { font-size: .84rem; color: var(--muted); }

.btn {
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-weight: 600; font-size: .85rem; padding: .52rem 1.05rem;
  border: 1px solid var(--accent); border-radius: 2px;
  background: var(--accent); color: var(--ground); cursor: pointer; text-decoration: none; display: inline-block;
}
.btn:hover { filter: brightness(1.08); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--rule); }
.btn-row { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; }

.msg { font-size: .92rem; margin: 0 0 1rem; padding: .6rem .8rem; border-left: 3px solid var(--rule); background: var(--ground); }
.msg.err { color: var(--mark); border-left-color: var(--mark); }
.msg.ok  { color: var(--ok); border-left-color: var(--ok); background: var(--ok-soft); }

/* ---------- homework form ---------- */

.who {
  display: flex; flex-wrap: wrap; gap: .4rem 1.2rem; align-items: baseline;
  font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .78rem; color: var(--muted);
  margin: 0 0 1.4rem;
}
.who b { color: var(--ink); font-weight: 500; }
.who form { display: inline; }
.who button {
  appearance: none; border: 0; background: none; padding: 0; cursor: pointer;
  font: inherit; color: var(--accent); text-decoration: underline; text-underline-offset: .15em;
}

.tasklist { list-style: none; margin: 0 0 1.2rem; padding: 0; }
.tasklist li {
  display: grid; grid-template-columns: 2.6rem 1fr; gap: .2rem .9rem; align-items: start;
  padding: .85rem 0; border-top: 1px solid var(--rule-soft);
}
.tasklist li:last-child { border-bottom: 1px solid var(--rule-soft); }
.tasklist .n {
  font-family: "JetBrains Mono", ui-monospace, monospace; font-size: 1.3rem; font-weight: 500;
  color: var(--accent); line-height: 1.1; padding-top: .1rem;
}
.tasklist .title {
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-weight: 600; font-size: .98rem; margin: 0 0 .35rem;
}
.tasklist .field { margin: 0; }
.tasklist .last {
  font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .7rem; color: var(--muted);
  margin-top: .3rem; overflow-wrap: anywhere;
}
.tasklist .last a { color: var(--muted); }
.tasklist .last a:hover { color: var(--accent); }
.tasklist .missing { color: var(--mark); }
.tasklist .late { color: var(--mark); font-weight: 500; }

/* ---------- history ---------- */

.history { width: 100%; border-collapse: collapse; font-size: .9rem; }
.history th, .history td { text-align: left; padding: .5rem .6rem .5rem 0; border-bottom: 1px solid var(--rule-soft); vertical-align: top; }
.history th {
  font-family: "JetBrains Mono", ui-monospace, monospace; font-weight: 500;
  font-size: .65rem; letter-spacing: .12em; text-transform: uppercase; color: var(--muted);
}
.history td.ts, .history td.n { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .8rem; white-space: nowrap; }
.history td.url { overflow-wrap: anywhere; }
.history td.url a { color: var(--ink); text-decoration-color: var(--rule); }
.history td.url a:hover { color: var(--accent); }
.history .late { color: var(--mark); font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .66rem; letter-spacing: .1em; text-transform: uppercase; margin-left: .4rem; }
.history-wrap { overflow-x: auto; }

/* Narrow screens: the columns squeeze down to a character a line, so stack
   each record into its own block and label the cells from their headers. */
@media (max-width: 40rem) {
  .history, .history tbody, .history tr, .history td { display: block; width: 100%; }
  .history thead { display: none; }
  .history tr { border-bottom: 1px solid var(--rule); padding: .55rem 0 .6rem; }
  .history tr:last-child { border-bottom: 0; }
  .history td, .history th { border: 0; padding: .1rem 0; }
  .history td[data-label]::before {
    content: attr(data-label); display: block;
    font-family: "JetBrains Mono", ui-monospace, monospace; font-weight: 500;
    font-size: .62rem; letter-spacing: .12em; text-transform: uppercase; color: var(--muted);
  }
  :root[data-lang="zh"] .history td[data-label-zh]::before { content: attr(data-label-zh); }
  :root[data-lang="ja"] .history td[data-label-ja]::before { content: attr(data-label-ja); }
  :root[data-lang="id"] .history td[data-label-id]::before { content: attr(data-label-id); }
  .history td.ts, .history td.n { white-space: normal; }
  .history td.n { text-align: left; }
}
.empty { color: var(--muted); font-size: .92rem; margin: 0; }

/* ---------- manager console ---------- */

.release-list { list-style: none; padding: 0; margin: 0 0 1.1rem; }
.release-list li { border-top: 1px solid var(--rule-soft); }
.release-list li:last-child { border-bottom: 1px solid var(--rule-soft); }
.release-row { display: flex; align-items: center; gap: .85rem; padding: .65rem .1rem; cursor: pointer; }
.release-row input {
  appearance: none; -webkit-appearance: none; position: relative; flex: 0 0 auto;
  width: 2.25rem; height: 1.2rem; margin: 0; border: 1.5px solid var(--muted); border-radius: 999px;
  background: transparent; cursor: pointer;
}
.release-row input::after {
  content: ""; position: absolute; top: .14rem; left: .16rem; width: .78rem; height: .78rem;
  border-radius: 50%; background: var(--muted); transition: transform .14s ease-out, background .14s;
}
.release-row input:checked { border-color: var(--accent); background: var(--accent-soft); }
.release-row input:checked::after { transform: translateX(1rem); background: var(--accent); }
.release-row input:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.rr-name { flex: 1 1 auto; font-size: .96rem; }
.rr-num { font-family: "JetBrains Mono", monospace; color: var(--muted); font-size: .8rem; margin-right: .45rem; }

.stack > .card + .card { margin-top: 1.4rem; }

.overview { width: 100%; border-collapse: collapse; font-size: .86rem; }
.overview th, .overview td { text-align: left; padding: .5rem .55rem .5rem 0; border-bottom: 1px solid var(--rule-soft); vertical-align: top; }
.overview th { font-family: "JetBrains Mono", ui-monospace, monospace; font-weight: 500; font-size: .63rem; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); white-space: nowrap; }
.overview td.id { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .8rem; overflow-wrap: anywhere; }
.overview td.id a { color: var(--ink); text-decoration-color: var(--rule); }
.overview td.id a:hover { color: var(--accent); }
.overview td.ts { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .76rem; white-space: nowrap; color: var(--muted); }
.overview td.days { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .8rem; white-space: nowrap; }
.overview td.days.soon { color: var(--accent); }
.overview td.days.closed { color: var(--mark); }
.overview td.t { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .72rem; white-space: nowrap; }
.overview td.t a { color: var(--ok); text-decoration: none; border-bottom: 1px dotted var(--ok); }
.overview td.t a.late { color: var(--mark); border-bottom-color: var(--mark); }
.overview td.t .none { color: var(--rule); }
.overview td.n { text-align: center; font-family: "JetBrains Mono", ui-monospace, monospace; }

.toolbar { display: flex; flex-wrap: wrap; gap: .6rem 1rem; align-items: center; margin: 0 0 1rem; font-size: .9rem; }
.toolbar form { display: flex; gap: .4rem; align-items: center; }
.toolbar input {
  font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .82rem; padding: .35rem .5rem;
  border: 1px solid var(--rule); border-radius: 2px; background: var(--ground); color: var(--ink); min-width: 14rem;
}
.toolbar .btn { padding: .36rem .8rem; font-size: .8rem; }
.toolbar a.plain { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.toolbar a.plain:hover { color: var(--accent); }
.count { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .74rem; color: var(--muted); }
.fineprint { color: var(--muted); font-size: .9rem; max-width: 60ch; margin: 1.2rem 0 0; }

/* ---------- uploaded images ---------- */

.field input[type="file"] {
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-size: .82rem; padding: .4rem .5rem; cursor: pointer;
}
.field input[type="file"]::file-selector-button {
  font: inherit; font-weight: 600; padding: .25rem .7rem; margin-right: .7rem;
  border: 1px solid var(--rule); border-radius: 2px; background: var(--panel); color: var(--ink); cursor: pointer;
}
.field input[type="file"]::file-selector-button:hover { border-color: var(--accent); color: var(--accent); }

.pair { display: grid; gap: .6rem .9rem; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
@media (max-width: 40rem) { .pair { grid-template-columns: 1fr; } }

.thumb {
  display: block; max-height: 6.5rem; max-width: 100%; width: auto; height: auto;
  border: 1px solid var(--rule); background: var(--ground); cursor: zoom-in; margin: .35rem 0 .1rem;
}
.thumb.zoom { max-height: none; cursor: zoom-out; }
.history td.img { min-width: 8rem; }
.history td.img .thumb { margin: 0; max-height: 5rem; }
.history td.img .thumb.zoom { max-height: none; max-width: 40rem; }
.imgnote { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .7rem; color: var(--muted); margin: 0; }

.thumbs { display: flex; flex-wrap: wrap; gap: .5rem .8rem; margin-top: .35rem; }
.thumbs figure { margin: 0; max-width: 100%; }
.thumbs .thumb { margin: 0 0 .1rem; }
.thumbs figure:has(.thumb.zoom) { flex: 1 1 100%; }

.imggroup { border-top: 1px solid var(--rule); padding: .9rem 0 .4rem; }
.imggroup:first-of-type { border-top: 0; padding-top: 0; }
.imgwho { margin: 0 0 .5rem; font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .86rem; }
.imgwho a { color: var(--ink); text-decoration-color: var(--rule); }
.imgwho a:hover { color: var(--accent); }
.imgtask { padding: .35rem 0 .7rem 1rem; border-left: 2px solid var(--rule-soft); margin: 0 0 .5rem; }
.imgtask-head {
  margin: 0 0 .2rem;
  font-family: Archivo, Arial, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", "Hiragino Sans", "Yu Gothic UI", "Meiryo", sans-serif;
  font-weight: 600; font-size: .92rem;
}
.imgtask-head .count { margin-left: .5rem; }