:root {
  --primary: #dc2626;
  --primary-dark: #991b1b;
  --accent: #ea580c;
  --bg: #f6f7fb;
  --card-bg: #ffffff;
  --text: #1f2430;
  --muted: #667085;
  --border: #e4e7ee;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(16,24,40,.06), 0 6px 16px rgba(16,24,40,.05);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif;
  line-height: 1.6;
}

header.site {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  padding: 28px 16px 22px;
  text-align: center;
}
header.site h1 { font-size: 1.5rem; font-weight: 700; }
header.site h1 a { color: #fff; text-decoration: none; }
header.site p { margin-top: 6px; color: rgba(255,255,255,.85); font-size: .9rem; }

.wrap { max-width: 880px; margin: 0 auto; padding: 24px 16px 40px; }

.back-link {
  display: inline-block; margin-bottom: 16px;
  color: var(--primary); text-decoration: none; font-size: .9rem;
}
.back-link:hover { text-decoration: underline; }

/* 首頁工具卡片 */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 20px;
}
.tool-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px 20px;
  text-decoration: none;
  color: var(--text);
  transition: transform .15s ease, box-shadow .15s ease;
}
.tool-card:hover { transform: translateY(-3px); box-shadow: 0 4px 10px rgba(16,24,40,.1), 0 12px 24px rgba(16,24,40,.08); }
.tool-card .icon { font-size: 2rem; margin-bottom: 10px; display: block; }
.tool-card h3 { font-size: 1.05rem; margin-bottom: 6px; }
.tool-card p { color: var(--muted); font-size: .85rem; }

.intro { margin: 18px 0 4px; color: var(--muted); font-size: .95rem; max-width: 640px; }

.privacy-badge {
  display: inline-flex; align-items: center; gap: 6px;
  background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0;
  padding: 6px 12px; border-radius: 999px; font-size: .8rem; font-weight: 600;
  margin-top: 10px;
}

/* 卡片式工具容器 */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px;
  margin-bottom: 20px;
}
.card h2 { font-size: 1.15rem; margin-bottom: 14px; }

/* 檔案拖曳上傳區 */
.drop-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 36px 20px;
  text-align: center;
  cursor: pointer;
  transition: border-color .15s ease, background .15s ease;
  background: var(--bg);
}
.drop-zone:hover, .drop-zone.dragover {
  border-color: var(--primary);
  background: #fef2f2;
}
.drop-zone .icon { font-size: 2.2rem; display: block; margin-bottom: 8px; }
.drop-zone .main-text { font-weight: 600; }
.drop-zone .sub-text { color: var(--muted); font-size: .85rem; margin-top: 4px; }
.drop-zone input[type="file"] { display: none; }

.file-list { margin-top: 16px; }
.file-item {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 12px; border: 1px solid var(--border); border-radius: 10px;
  margin-bottom: 8px; background: var(--bg);
}
.file-item .name { flex: 1; font-size: .92rem; word-break: break-all; }
.file-item .size { color: var(--muted); font-size: .8rem; white-space: nowrap; }
.file-item button {
  background: none; border: none; cursor: pointer; font-size: 1rem; color: var(--muted); padding: 2px 6px;
}
.file-item button:hover { color: var(--primary); }

.field-row {
  display: flex; gap: 10px; flex-wrap: wrap; align-items: center; margin-bottom: 14px;
}
input[type="text"], input[type="number"], select {
  font-size: 1rem;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  color: var(--text);
  font-family: inherit;
}
input[type="text"] { flex: 1; min-width: 200px; }
select { min-width: 140px; }
button.primary-btn, button {
  font-size: .95rem;
  padding: 10px 18px;
  border: none;
  border-radius: 8px;
  background: var(--primary);
  color: #fff;
  cursor: pointer;
  font-weight: 600;
}
button:disabled { opacity: .5; cursor: not-allowed; }
button:hover:not(:disabled) { background: var(--primary-dark); }
button.secondary {
  background: #fff; color: var(--primary); border: 1px solid var(--primary);
}
button.icon-btn {
  background: none; color: var(--muted); padding: 4px 8px; font-weight: normal;
}
button.icon-btn:hover:not(:disabled) { background: var(--border); color: var(--text); }

.result-card {
  display: flex; align-items: center; gap: 12px;
  padding: 14px 16px; border: 1px solid var(--border); border-radius: 10px;
  margin-bottom: 10px; background: var(--bg);
}
.result-card .label { flex: 1; }
.result-card .label .title { font-weight: 600; }
.result-card .label .meta { color: var(--muted); font-size: .82rem; }
.result-card a.download-link {
  display: inline-block; text-decoration: none; background: var(--accent); color: #fff;
  padding: 8px 16px; border-radius: 8px; font-size: .9rem; font-weight: 600;
}
.result-card a.download-link:hover { background: #c2410c; }

.progress-bar-outer {
  background: var(--border); border-radius: 999px; height: 8px; overflow: hidden; margin: 12px 0;
}
.progress-bar-inner { background: var(--primary); height: 100%; width: 0%; transition: width .2s ease; }

.hint { color: var(--muted); font-size: .82rem; margin-top: 4px; }
.error-box { background: #fef2f2; border: 1px solid #fecaca; color: #b91c1c; padding: 12px 14px; border-radius: 8px; font-size: .9rem; margin-top: 10px; }
.success-box { background: #ecfdf5; border: 1px solid #a7f3d0; color: #065f46; padding: 12px 14px; border-radius: 8px; font-size: .9rem; margin-top: 10px; }
.loading { color: var(--muted); font-size: .9rem; padding: 6px 0; }

article h2 { margin: 20px 0 8px; font-size: 1.15rem; }
article h2:first-child { margin-top: 0; }
article h3 { margin: 14px 0 6px; font-size: 1rem; }
article p, article li { color: var(--text); font-size: .95rem; margin-bottom: 8px; }
article ul { padding-left: 20px; }

footer.site {
  text-align: center; color: var(--muted); font-size: .82rem; padding: 24px 16px 40px;
}
footer.site nav { margin-bottom: 8px; }
footer.site nav a { color: var(--muted); text-decoration: none; margin: 0 8px; }
footer.site nav a:hover { text-decoration: underline; color: var(--primary); }

@media (max-width: 480px) {
  .field-row { flex-direction: column; align-items: stretch; }
  .result-card { flex-direction: column; align-items: stretch; }
}