/* pdfhv 界面样式：纸墨朱砂的克制书卷语言
   中性底 + 单一强调色（朱砂）锁定全页；竖排只作装饰，正文一律横排 */

:root {
  --paper: #f7f4ec;
  --paper-raised: #fffdf7;
  --ink: #1b1a17;
  --ink-soft: #4a4741;
  --ink-faint: #6b675f;
  --rule: #ddd6c4;
  --rule-strong: #c9c0a8;
  --accent: #9b3b2c;
  --accent-soft: #f0e2dd;
  --ok: #2f6b46;
  --danger: #a3281c;
  --step-1: 0.82rem;
  --step0: 0.94rem;
  --step1: 1.06rem;
  --step2: 1.3rem;
  --step3: 1.75rem;
  --step4: 2.4rem;
  --font-ui: system-ui, -apple-system, "Segoe UI", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --font-book: "Songti SC", "Source Han Serif SC", "Noto Serif CJK SC", "SimSun", "STSong", serif;
  --font-mono: ui-monospace, "Cascadia Mono", Consolas, monospace;
  --shadow: 0 1px 2px rgba(27, 26, 23, 0.06), 0 8px 24px rgba(27, 26, 23, 0.06);
}

* { box-sizing: border-box; }

html { color-scheme: light; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-ui);
  font-size: var(--step0);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { font-family: var(--font-book); font-weight: 600; line-height: 1.35; margin: 0; }

a { color: var(--accent); }

.skip {
  position: absolute; left: -9999px; top: 0; background: var(--accent); color: #fff;
  padding: 0.6rem 0.9rem; z-index: 10;
}
.skip:focus { left: 0.5rem; top: 0.5rem; }

/* ---------------------------------- 报头 ---------------------------------- */

.masthead {
  max-width: 74rem;
  margin: 0 auto;
  padding: 3.2rem 1.5rem 1.6rem;
  border-bottom: 1px solid var(--rule);
  position: relative;
}

.wordmark { margin: 0 0 1.1rem; display: flex; align-items: baseline; gap: 0.6rem; }
.wordmark-cn {
  font-family: var(--font-book); font-size: var(--step1); letter-spacing: 0.3em;
  border-bottom: 2px solid var(--accent); padding-bottom: 0.15rem;
}
.wordmark-en { font-family: var(--font-mono); font-size: var(--step-1); color: var(--ink-faint); letter-spacing: 0.08em; }

.masthead h1 { font-size: var(--step4); letter-spacing: 0.02em; }

.lede { max-width: 38em; color: var(--ink-soft); margin: 1rem 0 0; }
.lede strong { color: var(--ink); font-weight: 600; }

.sample { position: absolute; right: 1.5rem; top: 3rem; }
.sample-vertical {
  writing-mode: vertical-rl;
  font-family: var(--font-book);
  font-size: var(--step1);
  letter-spacing: 0.35em;
  color: var(--ink-faint);
  margin: 0;
  height: 15rem;
  border-right: 1px solid var(--rule-strong);
  padding-right: 0.5rem;
}

/* ---------------------------------- 面板 ---------------------------------- */

main { max-width: 74rem; margin: 0 auto; padding: 2.4rem 1.5rem 4rem; }

.panel { animation: rise 0.32s ease-out; }
@keyframes rise { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@media (prefers-reduced-motion: reduce) {
  .panel { animation: none; }
  * { transition: none !important; }
}

.panel h2 { font-size: var(--step2); margin-bottom: 0.6rem; }

/* 拖放区 */

.dropzone {
  background: var(--paper-raised);
  border: 1.5px dashed var(--rule-strong);
  border-radius: 10px;
  padding: 3.4rem 1.5rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.18s ease, background 0.18s ease;
  box-shadow: var(--shadow);
}
.dropzone:hover, .dropzone:focus-visible { border-color: var(--accent); }
.dropzone.is-over { border-color: var(--accent); background: var(--accent-soft); border-style: solid; }
.dropzone:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.drop-icon { width: 2.2rem; height: 2.2rem; color: var(--accent); display: block; margin: 0 auto 0.9rem; }
.drop-title { display: block; font-family: var(--font-book); font-size: var(--step1); margin: 0 0 0.5rem; }
.linklike { color: var(--accent); border-bottom: 1px solid currentColor; margin-left: 0.3em; }
.drop-hint { display: block; margin: 0; color: var(--ink-faint); font-size: var(--step-1); }
.visually-hidden {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* 选项 */

.options {
  margin-top: 2rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1.6rem 2.4rem;
}

.opt-group { border: 0; border-top: 1px solid var(--rule); padding: 1rem 0 0; margin: 0; }
.opt-group legend {
  font-family: var(--font-book); font-size: var(--step1); padding: 0 0.6rem 0 0;
  color: var(--ink);
}
.check { display: flex; gap: 0.6rem; align-items: flex-start; padding: 0.32rem 0; cursor: pointer; }
.check input { flex: none; width: 1.05rem; height: 1.05rem; margin-top: 0.28rem; accent-color: var(--accent); }
.check span { color: var(--ink-soft); }

.range { display: flex; align-items: center; gap: 0.5rem; flex-wrap: wrap; }
.range label { color: var(--ink-faint); font-size: var(--step-1); }
.range input {
  width: 5.2rem; padding: 0.35rem 0.5rem; font: inherit;
  border: 1px solid var(--rule-strong); border-radius: 6px; background: var(--paper-raised); color: var(--ink);
}
.range input:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.hint { color: var(--ink-faint); font-size: var(--step-1); margin: 0.6rem 0 0; }
.env-hint { grid-column: 1 / -1; margin: 0; color: var(--ink-faint); font-size: var(--step-1); }
.env-hint.warn { color: var(--danger); }

/* 进度 */

.file-line { font-family: var(--font-mono); font-size: var(--step-1); color: var(--ink-faint); margin: 0.4rem 0 1.2rem; word-break: break-all; }
.bar { height: 8px; background: var(--rule); border-radius: 999px; overflow: hidden; }
.bar span { display: block; height: 100%; width: 0; background: var(--accent); transition: width 0.25s ease; }
.progress-text { margin: 0.8rem 0 1.4rem; color: var(--ink-soft); }

/* 结果 */

.stats { display: flex; flex-wrap: wrap; gap: 0.6rem 1.4rem; margin: 1.2rem 0 1.6rem; padding: 0; }
.stats div { display: flex; align-items: baseline; gap: 0.45rem; }
.stats dt { color: var(--ink-faint); font-size: var(--step-1); }
.stats dd { margin: 0; font-family: var(--font-mono); font-size: var(--step1); }

.downloads { display: flex; flex-wrap: wrap; gap: 0.8rem; margin-bottom: 2rem; }

.btn {
  font: inherit; font-family: var(--font-book); font-size: var(--step1);
  border: 1px solid var(--accent); background: var(--accent); color: #fff;
  padding: 0.6rem 1.2rem; border-radius: 6px; cursor: pointer;
  text-decoration: none; display: inline-flex; align-items: center; gap: 0.5rem;
  transition: background 0.15s ease, color 0.15s ease;
}
.btn:hover { background: #863226; }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.btn.ghost { background: transparent; color: var(--accent); }
.btn.ghost:hover { background: var(--accent-soft); }
.btn .size { font-family: var(--font-mono); font-size: var(--step-1); opacity: 0.85; }

.preview-head { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; border-top: 1px solid var(--rule); padding-top: 1.4rem; }
.preview-head h3 { font-size: var(--step1); }
.preview-head .hint { margin: 0; }

.preview {
  background: var(--paper-raised);
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 1.6rem 1.8rem;
  margin-top: 0.9rem;
  max-height: 34rem;
  overflow: auto;
  font-family: var(--font-book);
  font-size: var(--step1);
  line-height: 1.95;
}
.preview h4 { font-size: var(--step1); margin: 1.4rem 0 0.6rem; letter-spacing: 0.04em; }
.preview h4:first-child { margin-top: 0; }
.preview p { text-indent: 2em; margin: 0.35em 0; }
.preview p.note { font-size: 0.9em; color: var(--ink-soft); text-indent: 1em; }
.preview p.marginal { text-indent: 0; text-align: center; color: var(--ink-faint); font-size: 0.85em; }
.preview .ellipsis { text-indent: 0; color: var(--ink-faint); text-align: center; }

.actions { margin-top: 1.6rem; }
.err-reason { font-family: var(--font-mono); color: var(--danger); background: var(--accent-soft); border-radius: 6px; padding: 0.7rem 0.9rem; }

/* ---------------------------------- 页脚 ---------------------------------- */

.footer { border-top: 1px solid var(--rule); background: var(--paper-raised); }
.cols {
  max-width: 74rem; margin: 0 auto; padding: 2.6rem 1.5rem 4rem;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr)); gap: 2rem 2.6rem;
}
.footer h3 { font-size: var(--step1); margin-bottom: 0.7rem; }
.footer ol, .footer ul { margin: 0; padding-left: 1.2em; color: var(--ink-soft); font-size: var(--step-1); }
.footer li { margin: 0.3rem 0; }
.footer p { margin: 0.5rem 0; color: var(--ink-soft); font-size: var(--step-1); }
.mono { font-family: var(--font-mono); }
.small { font-size: 0.78rem; }

/* ---------------------------------- 窄屏 ---------------------------------- */

@media (max-width: 60rem) {
  .sample { display: none; }
  .masthead { padding-top: 2.4rem; }
  .masthead h1 { font-size: var(--step3); }
}

@media (max-width: 34rem) {
  .dropzone { padding: 2.4rem 1rem; }
  .preview { padding: 1.2rem 1.1rem; }
  .stats { gap: 0.4rem 1rem; }
}