:root {
  --paper: #f7f4ee;
  --sheet: #fffdf9;
  --ink: #23201c;
  --ink-2: #5b554c;
  --ink-3: #8a8378;
  --rule: #e3ddd2;
  --rule-strong: #cfc7b8;
  --accent: #9c3f24;
  --accent-soft: #f3e4dc;
  --water: #e9eff1;
  --water-ink: #3d5a66;
  --ok: #3f6b45;
  --ok-soft: #e4ede2;
  --warn: #8a5a12;
  --warn-soft: #f5ead3;
  --bar: #23609f;
  --focus: #9c3f24;
  --serif: 'Noto Serif TC', 'Songti TC', 'PMingLiU', serif;
  --sans: 'Noto Sans TC', 'PingFang TC', 'Microsoft JhengHei', system-ui, sans-serif;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #1b1a18;
    --sheet: #22211e;
    --ink: #ece7de;
    --ink-2: #b9b2a6;
    --ink-3: #8c867b;
    --rule: #34322d;
    --rule-strong: #46433c;
    --accent: #e08a6a;
    --accent-soft: #3a2821;
    --water: #1f2a2e;
    --water-ink: #9fbcc7;
    --ok: #8fbf92;
    --ok-soft: #22301f;
    --warn: #e0b060;
    --warn-soft: #33291a;
    --bar: #3987e5;
    --focus: #e08a6a;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 16px/1.75 var(--sans);
  letter-spacing: 0.01em;
}
h1, h2, h3 { font-family: var(--serif); font-weight: 600; line-height: 1.35; margin: 0; }
p { margin: 0; }
button, input, select, textarea { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }
[hidden] { display: none !important; }

.wrap { max-width: 760px; margin: 0 auto; padding: 0 16px; }

/* ── 頁首 ───────────────────────── */
.masthead { padding: 40px 0 28px; border-bottom: 1px solid var(--rule-strong); }
.masthead .kicker { font-size: 13px; color: var(--ink-3); letter-spacing: 0.2em; }
.masthead h1 { font-size: clamp(28px, 6vw, 38px); margin-top: 6px; letter-spacing: 0.06em; }
.masthead .who { margin-top: 10px; color: var(--ink-2); font-size: 15px; }

/* ── 表單元件 ───────────────────── */
label.field { display: block; margin-bottom: 18px; }
label.field > span { display: block; font-size: 14px; color: var(--ink-2); margin-bottom: 6px; }
input[type=text], input[type=number], input[type=password], select {
  width: 100%;
  padding: 10px 12px;
  background: var(--sheet);
  border: 1px solid var(--rule-strong);
  border-radius: 3px;
}
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 10px 22px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--sheet);
  border-radius: 3px;
  cursor: pointer;
  font-weight: 500;
  letter-spacing: 0.05em;
}
.btn:hover { background: var(--accent); border-color: var(--accent); }
.btn:disabled { opacity: 0.45; cursor: default; background: var(--ink); border-color: var(--ink); }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--rule-strong); }
.btn.ghost:hover { border-color: var(--ink); background: transparent; }
.btn.small { padding: 5px 12px; font-size: 14px; }
.btn.danger:hover { background: #8e2a1c; border-color: #8e2a1c; color: #fff; }

.error { color: var(--accent); font-size: 14px; min-height: 1.5em; margin-top: 6px; }

/* ── 登入 ───────────────────────── */
.login { max-width: 380px; margin: 44px 0 0; }
.facts { margin: 48px 0 80px; padding: 0; border-top: 1px solid var(--rule-strong); max-width: 560px; }
.facts div { display: grid; grid-template-columns: 6em 1fr; gap: 12px; padding: 12px 0; border-bottom: 1px solid var(--rule); font-size: 14px; }
.facts dt { font-family: var(--serif); font-weight: 600; color: var(--ink); }
.facts dd { margin: 0; color: var(--ink-2); }
.login h2 { font-size: 20px; margin-bottom: 4px; }
.login .lead { color: var(--ink-2); font-size: 14px; margin-bottom: 28px; }
.login .row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.login .btn { width: 100%; margin-top: 8px; padding: 12px; }

/* ── 進度列 ─────────────────────── */
.bar-top {
  position: sticky; top: 0; z-index: 5;
  background: color-mix(in srgb, var(--paper) 92%, transparent);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--rule);
}
.bar-top .wrap { display: flex; align-items: center; gap: 16px; min-height: 52px; }
.progress { display: flex; gap: 4px; flex: 1; min-width: 0; }
.progress a {
  flex: 1; min-width: 0;
  text-decoration: none; color: var(--ink-3);
  font-size: 12px; padding-top: 8px;
  border-top: 3px solid var(--rule);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.progress a.partial { border-top-color: var(--rule-strong); color: var(--ink-2); }
.progress a.done { border-top-color: var(--ink); color: var(--ink); }
.progress .short { display: none; font-family: var(--serif); }
.save-state { font-size: 13px; color: var(--ink-3); white-space: nowrap; }
.save-state.err { color: var(--accent); }

/* ── 大題 ───────────────────────── */
.part { padding: 44px 0 12px; scroll-margin-top: 56px; }
.part-head { display: grid; grid-template-columns: auto 1fr; gap: 0 18px; align-items: baseline; margin-bottom: 8px; }
.part-no { font-family: var(--serif); font-size: 44px; line-height: 1; color: var(--accent); font-weight: 600; grid-row: span 2; }
.part-head h2 { font-size: 22px; }
.part-head .sub { color: var(--ink-2); font-size: 15px; }
.part-intro { margin: 14px 0 0; padding: 12px 16px; border-left: 3px solid var(--rule-strong); color: var(--ink-2); font-size: 15px; background: var(--sheet); }

.q { padding: 26px 0; border-bottom: 1px dashed var(--rule); }
.q:last-child { border-bottom: 0; }
.q-label { font-weight: 600; margin-bottom: 4px; }
.q-hint { font-size: 14px; color: var(--ink-3); margin-bottom: 10px; }
.q.missing .q-label::after { content: '　尚未完成'; color: var(--accent); font-size: 13px; font-weight: 500; }

/* 勾選框：做成紙本的方框 */
.opts { display: grid; gap: 2px; margin-top: 10px; }
.opt { display: flex; gap: 12px; align-items: flex-start; padding: 6px 10px; margin: 0 -10px; border-radius: 3px; cursor: pointer; }
.opt:hover { background: var(--sheet); }
.opt input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.box {
  flex: none; width: 18px; height: 18px; margin-top: 5px;
  border: 1.5px solid var(--ink-2); background: var(--sheet);
  display: grid; place-items: center;
}
.opt input[type=radio] + .box { border-radius: 50%; }
.opt input:checked + .box { border-color: var(--ink); background: var(--ink); }
.opt input:checked + .box::after { content: ''; width: 8px; height: 8px; background: var(--sheet); }
.opt input[type=radio]:checked + .box::after { border-radius: 50%; }
.opt input[type=checkbox]:checked + .box::after { width: 9px; height: 5px; background: none; border: 2px solid var(--sheet); border-top: 0; border-right: 0; transform: translate(0, -1px) rotate(-45deg); }
.opt input:focus-visible + .box { outline: 2px solid var(--focus); outline-offset: 2px; }
.opt.off { opacity: 0.4; cursor: not-allowed; }
.opt.off:hover { background: none; }
.other-input { margin: 4px 0 0 30px; }
.other-input input { padding: 6px 10px; }

/* 書寫格：像作業紙的橫線 */
textarea {
  width: 100%;
  resize: vertical;
  padding: 4px 12px;
  border: 1px solid var(--rule-strong);
  border-radius: 3px;
  line-height: 32px;
  background-color: var(--sheet);
  background-image: repeating-linear-gradient(to bottom, transparent 0 31px, var(--rule) 31px 32px);
  background-attachment: local;
  background-position: 0 4px;
}
.lined { display: grid; grid-template-columns: auto 1fr; gap: 6px 10px; align-items: start; margin-top: 8px; }
.lined .pre { font-family: var(--serif); font-weight: 600; padding-top: 5px; min-width: 3em; }
.quote { margin: 8px 0 4px; padding-left: 14px; border-left: 2px solid var(--accent); color: var(--ink-2); font-size: 15px; }

/* 冰山表 */
.ice { margin-top: 14px; border: 1px solid var(--rule-strong); border-radius: 3px; overflow: hidden; background: var(--sheet); }
.ice-head, .ice-row { display: grid; grid-template-columns: 104px 1fr 1fr 1fr; }
.ice-head > div { padding: 10px 12px; font-size: 13px; font-weight: 600; color: var(--ink-2); }
.ice-head .above { background: var(--sheet); }
.ice-head .below { background: var(--water); color: var(--water-ink); }
.ice-head .tag { display: block; font-size: 11px; font-weight: 500; letter-spacing: 0.15em; opacity: 0.8; }
.ice-row { border-top: 1px solid var(--rule); }
.ice-row > .who { padding: 12px; font-family: var(--serif); font-weight: 600; white-space: nowrap; }
.ice-row > .cell { padding: 8px; }
.ice-row > .cell.below { background: var(--water); }
.ice-row textarea { min-height: 104px; background-color: var(--sheet); }
.ice-row .cell-label { display: none; }
.waterline { border-left: 2px dashed var(--water-ink); }

/* 五步驟 */
.steps { list-style: none; padding: 0; margin: 14px 0 0; display: grid; grid-template-columns: repeat(5, 1fr); border: 1px solid var(--rule-strong); border-radius: 3px; background: var(--sheet); }
.steps li { padding: 12px 12px 14px; border-left: 1px solid var(--rule); position: relative; }
.steps li:first-child { border-left: 0; }
.steps .n { font-family: var(--serif); font-size: 13px; color: var(--accent); }
.steps b { display: block; font-family: var(--serif); font-size: 17px; margin: 2px 0 4px; }
.steps b small { display: block; font-family: var(--sans); font-weight: 400; font-size: 11px; color: var(--ink-3); letter-spacing: 0.05em; }
.steps p { font-size: 13px; color: var(--ink-2); line-height: 1.6; }

.scenario { margin: 14px 0; padding: 16px 18px; background: var(--sheet); border: 1px solid var(--rule); border-radius: 3px; }
.scenario .tag { font-size: 12px; letter-spacing: 0.2em; color: var(--ink-3); }
.scenario p { margin-top: 4px; }
.info-text { color: var(--ink-2); font-size: 15px; }

.imsg-preview { margin-top: 18px; padding: 16px 18px; border: 1px dashed var(--rule-strong); border-radius: 3px; font-family: var(--serif); font-size: 17px; line-height: 1.9; }
.imsg-preview .tag { display: block; font-family: var(--sans); font-size: 12px; letter-spacing: 0.2em; color: var(--ink-3); margin-bottom: 4px; }
.imsg-preview .blank { color: var(--ink-3); border-bottom: 1px solid var(--rule-strong); padding: 0 1.5em; }

/* 第一部分送出 */
.stage { margin: 8px 0 12px; padding: 20px 24px; background: var(--sheet); border: 1px solid var(--rule-strong); border-left: 3px solid var(--accent); border-radius: 3px; }
.stage h3 { font-size: 17px; margin-bottom: 4px; }
.stage .note { color: var(--ink-2); font-size: 14px; }
.stage .actions { margin-top: 14px; }
.stage.sent { border-left-color: var(--ok); display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.stage.sent .note { flex: 1; min-width: 200px; }
.stamp.small { margin-top: 0; font-size: 14px; padding: 4px 10px; letter-spacing: 0.1em; border-color: var(--ok); color: var(--ok); }

/* 送出區 */
.submit-area { margin: 32px 0 80px; padding: 24px; background: var(--sheet); border: 1px solid var(--rule-strong); border-radius: 3px; }
.submit-area h3 { font-size: 18px; margin-bottom: 6px; }
.submit-area .note { color: var(--ink-2); font-size: 14px; }
.submit-area .actions { display: flex; gap: 10px; margin-top: 18px; flex-wrap: wrap; }
.submit-area .actions { align-items: center; }
.save-note { font-size: 14px; color: var(--ok); }
.save-note.err { color: var(--accent); }
.missing-list { margin: 12px 0 0; padding-left: 1.2em; font-size: 14px; color: var(--accent); }
.missing-list a { color: inherit; }

.stamp {
  display: inline-block; margin-top: 14px;
  padding: 6px 14px; border: 2px solid var(--accent); color: var(--accent);
  font-family: var(--serif); font-weight: 600; letter-spacing: 0.2em;
  transform: rotate(-3deg);
}
.readonly .opt { cursor: default; }
.readonly .opt.off { opacity: 1; }
.readonly .opt:not(:has(input:checked)) { opacity: 0.45; }
.readonly .opt:hover { background: none; }
.readonly textarea, .readonly input { pointer-events: none; }

.foot { color: var(--ink-3); font-size: 13px; padding: 24px 0 40px; border-top: 1px solid var(--rule); }
.linkbtn { background: none; border: 0; padding: 0; color: var(--ink-2); text-decoration: underline; text-underline-offset: 3px; cursor: pointer; font-size: 13px; }

@media (max-width: 640px) {
  .masthead { padding: 28px 0 20px; }
  .part-no { font-size: 34px; }
  .steps { grid-template-columns: 1fr; }
  .steps li { border-left: 0; border-top: 1px solid var(--rule); display: grid; grid-template-columns: 7.5em 1fr; gap: 0 10px; }
  .steps li:first-child { border-top: 0; }
  .steps .n { grid-column: 1 / -1; }
  .ice-head { display: none; }
  .ice-row { grid-template-columns: 1fr; }
  .ice-row > .who { background: var(--paper); border-bottom: 1px solid var(--rule); }
  .ice-row .cell-label { display: block; font-size: 12px; color: var(--ink-2); margin: 2px 2px 4px; }
  .ice-row .cell.below .cell-label { color: var(--water-ink); }
  .waterline { border-left: 0; border-top: 2px dashed var(--water-ink); }
  .save-state { font-size: 12px; }
  .progress .long { display: none; }
  .progress .short { display: inline; }
  .progress a { font-size: 13px; }
  .facts div { grid-template-columns: 1fr; gap: 0; }
}