/* Pub2MD Agent — paper-ink theme (Q1-D)
 * Paper cream background, deep ink text, cinnabar accent.
 * System fonts only: serif for the brand/hero, sans for the UI. */

:root {
  --paper: #f7f2e9;        /* page background */
  --paper-deep: #ede4d3;   /* hero band */
  --card: #fffdf8;
  --ink: #2b2620;
  --muted: #7a6f61;
  --line: #e0d6c4;
  --accent: #b3432f;       /* cinnabar */
  --accent-dark: #93341f;
  --accent-ink: #fdf9f1;
  --error: #7f1f1f;
  --serif: Georgia, "Songti SC", "STSong", "SimSun", serif;
  --sans: -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }

/* The hidden attribute must beat explicit display values below. */
[hidden] { display: none !important; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
}

/* ---------- header ---------- */

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 28px;
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.2px;
}
.logo { width: 30px; height: 30px; }

#user-box { display: flex; gap: 12px; align-items: center; color: var(--muted); font-size: 14px; }

/* ---------- hero band (Q2-B) ---------- */

#hero {
  text-align: center;
  padding: 56px 20px 88px;  /* extra bottom room for the overlapping card */
  background: linear-gradient(180deg, var(--paper) 0%, var(--paper-deep) 100%);
  border-bottom: 1px solid var(--line);
}

#hero h1 {
  margin: 0 0 14px;
  font-family: var(--serif);
  font-size: clamp(34px, 6vw, 52px);
  font-weight: 700;
  letter-spacing: 0.5px;
}

.hero-desc {
  margin: 0 auto;
  max-width: 640px;
  color: var(--muted);
  font-size: 16px;
}

/* ---------- cards ---------- */

main {
  max-width: 720px;
  margin: 0 auto 40px;
  padding: 0 16px;
  display: grid;
  gap: 20px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 26px 30px;
  box-shadow: 0 1px 3px rgba(60, 48, 30, 0.06);
}

/* The tool card floats up into the hero band. */
#tool-card {
  margin-top: -56px;
  box-shadow: 0 10px 30px rgba(60, 48, 30, 0.12);
}

.card h2 { margin: 0 0 16px; font-family: var(--serif); font-size: 19px; }
.card-head { display: flex; justify-content: space-between; align-items: baseline; }
.card-head h2 { margin-bottom: 12px; }

/* ---------- forms ---------- */

form { display: grid; gap: 14px; justify-items: start; }
label { display: grid; gap: 5px; font-size: 14px; color: var(--muted); }
input, select {
  font: inherit;
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--card);
  color: var(--ink);
  min-width: 260px;
}
input:focus, select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }

button {
  font: inherit;
  padding: 9px 22px;
  border: none;
  border-radius: 8px;
  background: var(--accent);
  color: var(--accent-ink);
  cursor: pointer;
}
button:hover:not(:disabled) { background: var(--accent-dark); }
button:disabled { opacity: 0.5; cursor: default; }
button.ghost {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--line);
  padding: 4px 14px;
}
button.ghost:hover { background: var(--paper); }

.error { color: var(--error); font-size: 14px; min-height: 1em; margin: 0; }

/* ---------- progress & results ---------- */

#progress-box { display: flex; align-items: center; gap: 10px; margin-top: 18px; color: var(--muted); }
.spinner {
  width: 16px; height: 16px;
  border: 2px solid var(--line);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

#result-box { margin-top: 20px; }
#result-box h3 { margin: 0 0 10px; font-family: var(--serif); font-size: 16px; }
#cost-note { color: var(--muted); font-weight: normal; }

#article-list, #history-list, #new-terms-list { list-style: none; padding: 0; margin: 0 0 12px; }
#article-list li, #history-list li {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 0;
  border-bottom: 1px dashed var(--line);
}
#article-list .title, #history-list .title { flex: 1; }
.meta { color: var(--muted); font-size: 13px; white-space: nowrap; }

#history-list a { color: var(--accent); }

details { margin-top: 12px; color: var(--muted); font-size: 14px; }

/* ---------- preview dialog ---------- */

dialog {
  width: min(860px, 92vw);
  max-height: 86vh;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 0;
  background: var(--card);
  color: var(--ink);
}
dialog::backdrop { background: rgba(43, 38, 32, 0.5); }
.dialog-bar {
  position: sticky; top: 0;
  display: flex; justify-content: space-between; align-items: center;
  padding: 10px 20px;
  background: var(--card);
  border-bottom: 1px solid var(--line);
  font-family: var(--serif);
  font-weight: 700;
}
#preview-body { padding: 10px 28px 28px; overflow-x: auto; }
#preview-body h1 { font-family: var(--serif); font-size: 23px; }
#preview-body h2 { font-family: var(--serif); font-size: 17px; }
#preview-body blockquote {
  margin: 10px 0; padding: 6px 14px;
  border-left: 3px solid var(--accent);
  background: var(--paper); color: var(--muted); font-size: 13px;
}
#preview-body .katex-display { overflow-x: auto; padding: 4px 0; }

/* ---------- footer (Q4-A) ---------- */

footer {
  border-top: 1px solid var(--line);
  padding: 22px 16px 26px;
  text-align: center;
  color: var(--muted);
  font-size: 14px;
}
footer nav { display: flex; justify-content: center; gap: 10px; flex-wrap: wrap; }
footer a { color: var(--accent); text-decoration: none; }
footer a:hover { text-decoration: underline; }
.copyright { margin: 8px 0 0; font-size: 12px; }

/* ---------- responsive ---------- */

@media (max-width: 520px) {
  header { padding: 10px 16px; }
  #hero { padding: 36px 16px 72px; }
  .card { padding: 20px 18px; }
  input, select { min-width: 0; width: 100%; }
  form { justify-items: stretch; }
}