/* ===== 數據偵探事務所 — 檔案卷宗風 ===== */
:root {
  --bg: #101216;
  --bg-soft: #14171d;
  --panel: #171a21;
  --panel-2: #1d212a;
  --line: #2a2f3a;
  --hairline: #232833;
  --text: #e6e2d8;
  --text-dim: #97938a;
  --accent: #c9a24b;
  --accent-soft: #e0c584;
  --green: #8aa87f;
  --red: #c0776a;
  --blue: #8199b8;
  --stamp: #a85f50;
  --code-bg: #0d0f13;
  --code-text: #d3d8e0;
  --blank-bg: #262b3b;
  --blank-bg-focus: #2e3447;
  --btn-text: #17130a;
  --mask: rgba(8, 9, 12, 0.8);
  --radius: 8px;
  /* 主畫面(standalone)模式的安全區;瀏覽器內一律為 0,不影響排版 */
  --sa-top: env(safe-area-inset-top, 0px);
  --sa-right: env(safe-area-inset-right, 0px);
  --sa-bottom: env(safe-area-inset-bottom, 0px);
  --sa-left: env(safe-area-inset-left, 0px);
  --statusbar-scrim: var(--bg);
  --font-display: "Palatino", "Palatino Linotype", Georgia, "Songti TC", "Noto Serif TC", serif;
  --font-body: "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", system-ui, sans-serif;
  --font-code: ui-monospace, "SF Mono", "Cascadia Code", Menlo, Consolas, monospace;
}

/* ===== 淺色主題:紙本卷宗 ===== */
:root[data-theme="light"] {
  --bg: #efe9dc;
  --bg-soft: #e9e2d2;
  --panel: #f8f4ea;
  --panel-2: #efe9da;
  --line: #cfc5ae;
  --hairline: #ddd4c0;
  --text: #2e2a20;
  --text-dim: #6e6757;
  --accent: #8a6a20;
  --accent-soft: #6e5417;
  --green: #47703f;
  --red: #9c4f3a;
  --blue: #45618a;
  --stamp: #9c4f3a;
  --code-bg: #f3efe2;
  --code-text: #35312a;
  --blank-bg: #e6dfcc;
  --blank-bg-focus: #ded5bf;
  --btn-text: #fdf9ee;
  --mask: rgba(58, 52, 40, 0.55);
  /* iOS 狀態列文字恆為白色,淺色主題下改鋪深色底才看得清楚 */
  --statusbar-scrim: #101216;
}
:root[data-theme="light"] .code-box,
:root[data-theme="light"] textarea.code-editor,
:root[data-theme="light"] .run-output pre,
:root[data-theme="light"] .step-body pre {
  border-color: var(--line);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { -webkit-text-size-adjust: 100%; background: var(--bg); }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.75;
  min-height: 100vh;
}

/* ===== 頂欄 ===== */
#topbar {
  display: flex;
  align-items: center;
  gap: 28px;
  padding: calc(12px + var(--sa-top)) calc(28px + var(--sa-right)) 12px calc(28px + var(--sa-left));
  /* 第一層只鋪在狀態列高度內,主畫面模式下讓頁面畫到狀態列底下仍保有對比 */
  background:
    linear-gradient(var(--statusbar-scrim), var(--statusbar-scrim)) top / 100% var(--sa-top) no-repeat,
    var(--bg);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 50;
}
.brand { cursor: pointer; white-space: nowrap; line-height: 1.25; }
.brand .brand-zh {
  display: block;
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--text);
}
.brand .brand-en {
  display: block;
  font-size: 0.58rem;
  letter-spacing: 3.5px;
  text-transform: uppercase;
  color: var(--accent);
}
#topbar nav { display: flex; gap: 2px; flex: 1; }
.nav-btn {
  background: transparent;
  border: none;
  border-bottom: 1px solid transparent;
  color: var(--text-dim);
  padding: 8px 14px;
  cursor: pointer;
  font-size: 0.88rem;
  font-family: inherit;
  letter-spacing: 1px;
}
.nav-btn:hover { color: var(--text); }
.nav-btn.active { color: var(--accent-soft); border-bottom-color: var(--accent); }

.theme-toggle {
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--text-dim);
  padding: 5px 12px;
  cursor: pointer;
  font-size: 0.78rem;
  font-family: inherit;
  letter-spacing: 2px;
  white-space: nowrap;
}
.theme-toggle:hover { color: var(--accent-soft); border-color: var(--accent); }

.rank-box { display: flex; align-items: center; gap: 12px; font-size: 0.8rem; }
#rank-name { color: var(--accent-soft); letter-spacing: 2px; font-family: var(--font-display); white-space: nowrap; }
.xp-bar {
  width: 96px; height: 2px;
  background: var(--line);
  overflow: hidden;
}
#xp-fill { height: 100%; width: 0%; background: var(--accent); transition: width .5s; }
#xp-text { color: var(--text-dim); white-space: nowrap; font-variant-numeric: tabular-nums; }

/* ===== 主區 ===== */
#main {
  max-width: 1080px;
  margin: 0 auto;
  padding: 36px calc(24px + var(--sa-right)) calc(90px + var(--sa-bottom)) calc(24px + var(--sa-left));
}

.hero { text-align: center; padding: 34px 0 26px; }
.hero .kicker {
  font-size: 0.72rem;
  letter-spacing: 5px;
  color: var(--accent);
  margin-bottom: 14px;
}
.hero h1 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: 6px;
  margin-bottom: 14px;
}
.hero p { color: var(--text-dim); max-width: 560px; margin: 0 auto; font-size: 0.93rem; }
.hero::after {
  content: "";
  display: block;
  width: 56px;
  margin: 26px auto 0;
  border-top: 1px solid var(--accent);
}

.section-title {
  font-size: 0.78rem;
  letter-spacing: 4px;
  color: var(--text-dim);
  margin: 44px 0 18px;
  display: flex;
  align-items: center;
  gap: 14px;
  text-transform: uppercase;
}
.section-title::after { content: ""; flex: 1; border-top: 1px solid var(--hairline); }

/* ===== 案件卡片 ===== */
.case-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 14px; }
.case-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 22px 18px;
  cursor: pointer;
  transition: border-color .15s, transform .15s;
  position: relative;
  overflow: hidden;
}
.case-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.case-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.file-tag {
  font-size: 0.66rem;
  letter-spacing: 3px;
  color: var(--accent);
  border: 1px solid var(--line);
  padding: 2px 9px;
}
.diff-meter { display: flex; gap: 3px; }
.diff-meter i { width: 13px; height: 3px; background: var(--line); }
.diff-meter i.on { background: var(--accent); }
.case-card h3 {
  font-family: var(--font-display);
  font-size: 1.12rem;
  letter-spacing: 1px;
  margin-bottom: 2px;
}
.case-card .case-sub { color: var(--text-dim); font-size: 0.83rem; margin-bottom: 10px; }
.case-card .dataset-tag {
  font-size: 0.76rem;
  color: var(--blue);
  margin-bottom: 10px;
  padding-left: 10px;
  border-left: 2px solid var(--blue);
  line-height: 1.4;
}
.case-card .case-desc { font-size: 0.86rem; color: var(--text-dim); margin-bottom: 16px; }
.progress-track { height: 2px; background: var(--hairline); overflow: hidden; }
.progress-fill { height: 100%; background: var(--green); transition: width .4s; }
.progress-label { font-size: 0.74rem; color: var(--text-dim); margin-top: 6px; letter-spacing: 1px; }
.stamp {
  position: absolute;
  top: 16px;
  right: -6px;
  transform: rotate(8deg);
  border: 2px solid var(--stamp);
  color: var(--stamp);
  font-family: var(--font-display);
  font-size: 0.8rem;
  letter-spacing: 6px;
  padding: 2px 12px 2px 16px;
  opacity: 0.9;
}

/* ===== 徽章 ===== */
.badge-row { display: flex; gap: 10px; flex-wrap: wrap; }
.badge-chip {
  border: 1px solid var(--accent);
  color: var(--accent-soft);
  padding: 5px 18px;
  font-size: 0.83rem;
  letter-spacing: 2px;
  font-family: var(--font-display);
}
.badge-chip.locked { border: 1px dashed var(--line); color: var(--text-dim); opacity: 0.55; }

/* ===== 案件內頁 ===== */
.case-layout { display: grid; grid-template-columns: 232px 1fr; gap: 20px; align-items: start; }
.step-nav {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px;
  position: sticky;
  top: calc(76px + var(--sa-top));
  max-height: calc(100vh - 96px - var(--sa-top));
  overflow-y: auto;
}
.step-nav .back-link { display: block; color: var(--text-dim); font-size: 0.8rem; cursor: pointer; margin-bottom: 12px; letter-spacing: 1px; }
.step-nav .back-link:hover { color: var(--accent); }
.step-nav-bar { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.step-toggle {
  display: none;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--text-dim);
  font-family: inherit;
  font-size: 0.85rem;
  letter-spacing: 1px;
  padding: 6px 12px;
  cursor: pointer;
}
.step-toggle:hover { color: var(--accent-soft); border-color: var(--accent); }
.step-toggle .chev { font-size: 0.7em; transition: transform .18s; }
.step-nav.open .step-toggle .chev { transform: rotate(180deg); }

/* 階級資訊:桌機在頂欄,手機頂欄讓位後改顯示在首頁 */
.rank-line {
  display: none;
  font-family: var(--font-display);
  color: var(--accent-soft);
  letter-spacing: 2px;
  margin-bottom: 12px;
}
.step-nav h4 {
  font-family: var(--font-display);
  font-size: 0.95rem;
  letter-spacing: 2px;
  margin-bottom: 10px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--hairline);
}
.step-item {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 6px 8px;
  font-size: 0.82rem;
  color: var(--text-dim);
  cursor: pointer;
  border-left: 2px solid transparent;
}
.step-item:hover { color: var(--text); }
.step-item.current { color: var(--accent-soft); border-left-color: var(--accent); background: var(--panel-2); }
.step-item.done { color: var(--green); }
.step-item.locked { opacity: 0.4; cursor: default; }
.step-item .s-no {
  font-family: var(--font-code);
  font-size: 0.7rem;
  color: inherit;
  opacity: 0.75;
  flex-shrink: 0;
  width: 18px;
}

.step-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 34px;
  min-height: 420px;
}
.step-kind {
  font-size: 0.68rem;
  color: var(--blue);
  letter-spacing: 4px;
  margin-bottom: 6px;
}
.step-panel h2 {
  font-family: var(--font-display);
  font-size: 1.4rem;
  letter-spacing: 1px;
  margin-bottom: 18px;
  color: var(--accent-soft);
}
.step-body { font-size: 0.95rem; }
.step-body p { margin-bottom: 12px; }
.step-body ul, .step-body ol { margin: 0 0 12px 22px; }
.step-body li { margin-bottom: 5px; }
.step-body code {
  font-family: var(--font-code);
  background: var(--code-bg);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 0.85em;
  color: var(--accent-soft);
}
.step-body pre {
  background: var(--code-bg);
  border: 1px solid var(--hairline);
  border-radius: 6px;
  padding: 12px 16px;
  overflow-x: auto;
  margin-bottom: 14px;
  font-size: 0.85rem;
  line-height: 1.6;
}
.step-body pre code { background: none; padding: 0; color: var(--text); }
.step-body blockquote {
  border-left: 2px solid var(--accent);
  padding: 8px 18px;
  margin-bottom: 14px;
  color: var(--text-dim);
}
.step-body strong { color: var(--accent-soft); font-weight: 600; }
.story-frame {
  border: 1px solid var(--hairline);
  background: var(--bg-soft);
  padding: 18px 22px;
  margin-bottom: 16px;
}
.story-frame blockquote {
  border-left: 2px solid var(--line);
  font-family: var(--font-display);
  letter-spacing: 0.5px;
}

/* ===== 按鈕 ===== */
.btn {
  background: var(--accent);
  color: var(--btn-text);
  border: 1px solid var(--accent);
  padding: 9px 24px;
  border-radius: 5px;
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 2px;
  cursor: pointer;
  font-family: inherit;
}
.btn:hover { background: var(--accent-soft); border-color: var(--accent-soft); }
.btn:disabled { opacity: 0.35; cursor: not-allowed; }
.btn.ghost {
  background: transparent;
  color: var(--text-dim);
  border: 1px solid var(--line);
  font-weight: 400;
}
.btn.ghost:hover { color: var(--text); border-color: var(--text-dim); background: transparent; }
.btn.small { padding: 5px 14px; font-size: 0.8rem; }
.btn-row { display: flex; gap: 10px; margin-top: 18px; flex-wrap: wrap; align-items: center; }

/* ===== 測驗 / 決策 ===== */
.quiz-opt {
  display: block;
  width: 100%;
  text-align: left;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  border-radius: 6px;
  padding: 12px 18px;
  margin-bottom: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  font-family: inherit;
  line-height: 1.6;
}
.quiz-opt:hover { border-color: var(--accent); }
.quiz-opt.correct { border-color: var(--green); border-left-width: 3px; }
.quiz-opt.wrong { border-color: var(--red); border-left-width: 3px; opacity: 0.7; }
.quiz-opt:disabled { cursor: default; }

/* ===== 程式碼區 ===== */
.code-box {
  background: var(--code-bg);
  border: 1px solid var(--hairline);
  border-radius: 6px;
  padding: 14px 18px;
  font-family: var(--font-code);
  font-size: 0.87rem;
  line-height: 2;
  overflow-x: auto;
  white-space: pre;
  margin: 14px 0;
  color: var(--code-text);
}
.code-box input.blank {
  background: var(--blank-bg);
  border: none;
  border-bottom: 1.5px solid var(--accent);
  border-radius: 3px 3px 0 0;
  color: var(--accent-soft);
  font-family: var(--font-code);
  font-size: 0.87rem;
  padding: 1px 8px;
  outline: none;
}
.code-box input.blank:focus { background: var(--blank-bg-focus); }
.code-box input.blank.blank-ok { border-bottom-color: var(--green); color: var(--green); }

textarea.code-editor {
  width: 100%;
  min-height: 220px;
  background: var(--code-bg);
  border: 1px solid var(--hairline);
  border-radius: 6px;
  color: var(--code-text);
  font-family: var(--font-code);
  font-size: 0.87rem;
  line-height: 1.65;
  padding: 14px 16px;
  resize: vertical;
  outline: none;
  tab-size: 4;
  margin: 14px 0 0;
}
textarea.code-editor:focus { border-color: var(--accent); }

/* ===== Parsons 積木 ===== */
.parsons-zone { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 14px 0; }
.parsons-col {
  background: var(--bg-soft);
  border: 1px dashed var(--line);
  border-radius: 6px;
  padding: 10px;
  min-height: 170px;
}
.parsons-col h5 {
  font-size: 0.7rem;
  color: var(--text-dim);
  margin-bottom: 10px;
  font-weight: 400;
  letter-spacing: 2px;
}
.parsons-line {
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 7px 11px;
  font-family: var(--font-code);
  font-size: 0.78rem;
  margin-bottom: 6px;
  cursor: pointer;
  white-space: pre;
  overflow-x: auto;
}
.parsons-line:hover { border-color: var(--accent); }
.parsons-col.answer .parsons-line { border-left: 2px solid var(--accent); }

/* ===== 執行輸出 ===== */
.run-output {
  margin-top: 16px;
  border: 1px solid var(--hairline);
  border-radius: 6px;
  overflow: hidden;
}
.run-output .out-head {
  background: var(--panel-2);
  font-size: 0.68rem;
  padding: 5px 14px;
  color: var(--text-dim);
  letter-spacing: 3px;
}
.run-output pre {
  background: var(--code-bg);
  padding: 12px 16px;
  font-family: var(--font-code);
  font-size: 0.82rem;
  line-height: 1.6;
  overflow-x: auto;
  margin: 0;
  max-height: 420px;
  overflow-y: auto;
  white-space: pre-wrap;
}
.run-output pre.err { color: var(--red); }
.run-output img { display: block; max-width: 100%; background: #fff; padding: 8px; }
.err-hint {
  border: 1px solid var(--line);
  border-left: 2px solid var(--red);
  border-radius: 0 6px 6px 0;
  padding: 10px 14px;
  font-size: 0.86rem;
  margin-top: 10px;
  color: var(--text-dim);
}

/* ===== 回饋訊息 ===== */
.feedback {
  margin-top: 16px;
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 0.9rem;
}
.feedback.ok { border-left: 2px solid var(--green); }
.feedback.no { border-left: 2px solid var(--red); }
.feedback.info { border-left: 2px solid var(--blue); }
.fb-tag {
  display: inline-block;
  font-size: 0.68rem;
  letter-spacing: 3px;
  padding: 1px 9px;
  margin-right: 10px;
  vertical-align: 2px;
  border: 1px solid;
  border-radius: 3px;
}
.feedback.ok .fb-tag { color: var(--green); }
.feedback.no .fb-tag { color: var(--red); }
.feedback.info .fb-tag { color: var(--blue); }
.err-hint .fb-tag { color: var(--red); }

.hint-box {
  border: 1px solid var(--hairline);
  border-left: 2px solid var(--blue);
  padding: 10px 14px;
  font-size: 0.87rem;
  margin-top: 10px;
  color: var(--text-dim);
}
.hint-box pre { background: var(--code-bg); padding: 10px 12px; margin-top: 8px; overflow-x: auto; font-size: 0.8rem; }

/* ===== 魔王關 rubric ===== */
.rubric-list { margin: 16px 0; }
.rubric-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 11px 16px;
  margin-bottom: 8px;
  font-size: 0.89rem;
}
.rubric-item.pass { border-left: 2px solid var(--green); }
.r-box {
  width: 15px; height: 15px;
  border: 1px solid var(--text-dim);
  border-radius: 3px;
  flex-shrink: 0;
  margin-top: 6px;
  position: relative;
}
.r-box.on { border-color: var(--green); background: var(--green); }
.r-box.on::after {
  content: "✓";
  position: absolute;
  inset: 0;
  color: #10130e;
  font-size: 11px;
  line-height: 15px;
  text-align: center;
}
.rubric-item .r-label { flex: 1; }
.rubric-item .r-label strong { display: block; }
.rubric-item .r-label span { color: var(--text-dim); font-size: 0.82rem; }
.rubric-item summary { cursor: pointer; font-size: 0.78rem; color: var(--blue); letter-spacing: 1px; }

/* ===== 卡片庫 ===== */
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 12px; }
.concept-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  cursor: pointer;
}
.concept-card:hover { border-color: var(--accent); }
.concept-card .cc-cat { font-size: 0.68rem; color: var(--blue); letter-spacing: 2px; }
.concept-card h4 { font-family: var(--font-display); margin: 6px 0 6px; font-size: 1rem; letter-spacing: 0.5px; }
.concept-card .cc-preview { font-size: 0.8rem; color: var(--text-dim); }

.modal-mask {
  position: fixed; inset: 0;
  background: var(--mask);
  z-index: 100;
  display: flex; align-items: center; justify-content: center;
  padding: 28px;
}
.modal {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  max-width: 720px;
  width: 100%;
  max-height: 85vh;
  overflow-y: auto;
  padding: 28px 32px;
}
.modal h3 { font-family: var(--font-display); color: var(--accent-soft); letter-spacing: 1px; margin-bottom: 14px; }

/* ===== 沙盒 ===== */
.sandbox-bar { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; margin-bottom: 6px; }
.sandbox-bar label { font-size: 0.85rem; color: var(--text-dim); letter-spacing: 1px; }
.sandbox-bar select {
  background: var(--panel);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 8px 12px;
  font-family: inherit;
  font-size: 0.88rem;
  max-width: 100%;
}
.snippet-row { display: flex; gap: 8px; flex-wrap: wrap; margin: 12px 0; }
.snippet-btn {
  background: transparent;
  border: 1px solid var(--hairline);
  color: var(--text-dim);
  font-size: 0.76rem;
  font-family: var(--font-code);
  padding: 4px 10px;
  border-radius: 4px;
  cursor: pointer;
}
.snippet-btn:hover { color: var(--accent-soft); border-color: var(--accent); }

/* ===== Python 狀態列 ===== */
.py-status {
  position: fixed;
  left: calc(18px + var(--sa-left));
  bottom: calc(18px + var(--sa-bottom));
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 8px 16px;
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  gap: 10px;
  z-index: 60;
  max-width: min(420px, calc(100vw - 36px));
}
.py-status.hidden { display: none; }
.py-status.ready { border-color: var(--green); color: var(--green); }
.py-status.error { border-color: var(--red); color: var(--red); }
.spinner {
  width: 12px; height: 12px;
  border: 2px solid var(--line);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
  flex-shrink: 0;
}
.py-status.ready .spinner, .py-status.error .spinner { display: none; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ===== Toast ===== */
#toast-zone {
  position: fixed;
  right: calc(18px + var(--sa-right));
  bottom: calc(18px + var(--sa-bottom));
  z-index: 200;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.toast {
  background: var(--panel);
  border: 1px solid var(--accent);
  border-radius: 5px;
  padding: 10px 20px;
  font-size: 0.87rem;
  letter-spacing: 1px;
  animation: toast-in 0.3s ease;
}
@keyframes toast-in { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }

/* ===== 報告 ===== */
.report-paper {
  background: #efe8d8;
  color: #33301f;
  padding: 28px 32px;
  font-size: 0.92rem;
  margin: 16px 0;
  border-radius: 3px;
}
.report-paper h3 {
  font-family: var(--font-display);
  border-bottom: 1px solid #b3a37e;
  padding-bottom: 10px;
  margin-bottom: 16px;
  color: #4a3d20;
  letter-spacing: 2px;
}
.report-paper strong { color: #6b5316; }
.report-paper ul { margin: 0 0 10px 22px; }

textarea.report-input {
  width: 100%;
  min-height: 140px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--text);
  font-family: inherit;
  font-size: 0.92rem;
  line-height: 1.7;
  padding: 14px 16px;
  resize: vertical;
  margin-top: 10px;
}

/* ===== 響應式 ===== */
@media (max-width: 1024px) {
  #main { padding: 28px calc(20px + var(--sa-right)) calc(80px + var(--sa-bottom)) calc(20px + var(--sa-left)); }
  .case-layout { grid-template-columns: 200px 1fr; gap: 14px; }
  .step-panel { padding: 24px 24px; }
}

@media (max-width: 820px) {
  /* 頂欄壓成單行:導覽移到底部固定列,階級名與 XP 長條讓位 */
  #topbar {
    flex-wrap: nowrap;
    gap: 10px;
    padding: calc(10px + var(--sa-top)) calc(14px + var(--sa-right)) 10px calc(14px + var(--sa-left));
  }
  .rank-box { margin-left: auto; gap: 8px; }
  #rank-name, .xp-bar { display: none; }
  /* XP 進度改用頂欄底部的細線呈現,不佔任何版面高度 */
  #topbar::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -1px;
    height: 2px;
    width: var(--xp-pct, 0%);
    background: var(--accent);
    transition: width .5s;
  }

  /* 導覽:底部固定列(拇指可及,且不再推擠內容) */
  #topbar nav {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 60;
    flex: none;
    gap: 0;
    justify-content: space-around;
    background: var(--panel);
    border-top: 1px solid var(--line);
    padding: 4px var(--sa-right) calc(4px + var(--sa-bottom)) var(--sa-left);
  }
  .nav-btn {
    flex: 1;
    text-align: center;
    padding: 11px 4px;
    font-size: 0.88rem;
    letter-spacing: 1px;
    border-bottom: none;
    border-top: 2px solid transparent;
  }
  .nav-btn.active { border-bottom: none; border-top-color: var(--accent); }
  body { padding-bottom: calc(52px + var(--sa-bottom)); }

  .case-layout { grid-template-columns: 1fr; }
  .step-nav {
    position: static;
    max-height: none;
    padding: 8px 12px;
  }
  .step-nav h4 { display: none; }
  .step-nav .back-link { margin-bottom: 0; }
  /* 步驟清單預設收合,點「步驟 N / M」才展開 */
  .step-toggle { display: inline-flex; }
  #step-nav-list { display: none; }
  .step-nav.open #step-nav-list {
    display: flex;
    margin-top: 8px;
    overflow-x: auto;
    gap: 4px;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
  }
  .step-item {
    flex-shrink: 0;
    border: 1px solid var(--line);
    border-radius: 4px;
    padding: 6px 10px;
    max-width: 190px;
  }
  .step-item.current { border-color: var(--accent); }
  .step-item span:last-child { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

  .rank-line { display: block; }

  .hero { padding: 22px 0 18px; }
  .hero h1 { font-size: 1.55rem; letter-spacing: 4px; }
  .step-panel { min-height: 0; }

  /* 讓浮動元素避開底部導覽列 */
  .py-status { bottom: calc(60px + var(--sa-bottom)); }
  #toast-zone { bottom: calc(60px + var(--sa-bottom)); }
}

@media (max-width: 640px) {
  /* 底部導覽列的高度與安全區由 body 的 padding 處理,這裡不重複加 */
  #main { padding: 20px calc(14px + var(--sa-right)) 28px calc(14px + var(--sa-left)); }

  .hero h1 { font-size: 1.35rem; }
  .hero p { font-size: 0.88rem; }
  .case-grid { grid-template-columns: 1fr; }
  .card-grid { grid-template-columns: 1fr; }

  .step-panel { padding: 18px 16px; }
  .step-panel h2 { font-size: 1.18rem; }
  .step-body { font-size: 0.92rem; }
  .parsons-zone { grid-template-columns: 1fr; }
  .parsons-col { min-height: 0; }
  .code-box { font-size: 0.8rem; padding: 12px 12px; }
  textarea.code-editor { font-size: 0.8rem; }

  .btn-row .btn { flex: 1 1 auto; text-align: center; }
  .quiz-opt { padding: 12px 14px; }
  .modal-mask { padding: 14px; }
  .modal { padding: 20px 18px; }
  .report-paper { padding: 20px 18px; }
  #toast-zone { left: calc(14px + var(--sa-left)); right: calc(14px + var(--sa-right)); }
  .toast { text-align: center; }
  .py-status { left: calc(14px + var(--sa-left)); right: calc(14px + var(--sa-right)); bottom: calc(56px + var(--sa-bottom)); }
}

/* 窄機身(iPhone SE 等):只收緊字距,不縮字級 */
@media (max-width: 380px) {
  .brand .brand-zh { letter-spacing: 1px; }
  #topbar { gap: 8px; }
  .theme-toggle { padding: 5px 9px; letter-spacing: 1px; }
}