/* ── kami 风格参考：纸张质感、留白、墨蓝强调色 ─────────────────── */
:root {
  --bg: #faf8f5;
  --surface: #ffffff;
  --ink: #1a1a2e;
  --ink-light: #4a4a6a;
  --accent: #2d5f8a;
  --accent-hover: #1d4a6f;
  --border: #e8e4df;
  --shadow: rgba(0, 0, 0, 0.06);
  --radius: 8px;
  --font-body: "Noto Serif SC", "Georgia", serif;
  --font-sans: "Inter", "Noto Sans SC", system-ui, sans-serif;
  --max-width: 960px;
}

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

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); text-decoration: underline; }

/* ── Header ─────────────────────────────────────────────────────── */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-bar {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-brand {
  font-family: var(--font-body);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--ink);
}

.nav-links { display: flex; gap: 16px; margin-left: auto; }
.nav-links a { font-size: 0.9rem; color: var(--ink-light); }
.nav-links a:hover { color: var(--accent); }

/* ── Container ──────────────────────────────────────────────────── */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px;
}

/* ── Date Navigation ────────────────────────────────────────────── */
.date-nav {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.date-title {
  font-family: var(--font-body);
  font-size: 1.5rem;
  font-weight: 700;
}

.date-nav-btn {
  display: inline-block;
  padding: 6px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.85rem;
  color: var(--ink-light);
  transition: all 0.2s;
}
.date-nav-btn:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

/* ── Date Chips ─────────────────────────────────────────────────── */
.date-quick-nav {
  margin-top: 32px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--ink-light);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.date-chip {
  padding: 4px 10px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 0.8rem;
  color: var(--ink-light);
}
.date-chip:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.date-chip.active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* ── Paper Card ─────────────────────────────────────────────────── */
.paper-list { display: flex; flex-direction: column; gap: 16px; }

.paper-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  transition: box-shadow 0.2s;
}
.paper-card:hover { box-shadow: 0 2px 12px var(--shadow); }

.paper-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}

.paper-title {
  font-family: var(--font-body);
  font-size: 1.1rem;
  font-weight: 600;
  line-height: 1.5;
  flex: 1;
}
.paper-title a { color: var(--ink); }
.paper-title a:hover { color: var(--accent); }

.paper-upvotes {
  font-size: 0.85rem;
  color: var(--ink-light);
  white-space: nowrap;
}

.paper-one-line, .paper-abstract-preview {
  margin-top: 8px;
  color: var(--ink-light);
  font-size: 0.92rem;
  line-height: 1.6;
}

.paper-meta {
  margin-top: 8px;
  font-size: 0.82rem;
  color: var(--ink-light);
}

.paper-tags {
  margin-top: 8px;
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.tag {
  display: inline-block;
  padding: 2px 8px;
  background: #eef3f8;
  color: var(--accent);
  border-radius: 3px;
  font-size: 0.75rem;
  font-weight: 500;
}

.paper-footer {
  margin-top: 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.summary-badge {
  font-size: 0.8rem;
  padding: 2px 8px;
  border-radius: 3px;
}
.summary-none { background: #f0f0f0; color: #888; }
.summary-pending { background: #fff3e0; color: #e67e22; }
.summary-processing { background: #e3f2fd; color: #1976d2; }
.summary-done { background: #e8f5e9; color: #388e3c; }
.summary-failed, .summary-permanent_failure { background: #fce4ec; color: #c62828; }

.btn-detail {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
}

/* ── Empty State ────────────────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--ink-light);
}
.empty-state p:first-child { font-size: 1.2rem; }
.hint { font-size: 0.85rem; margin-top: 8px; }

/* ── Paper Detail ───────────────────────────────────────────────── */
.paper-detail { max-width: 780px; margin: 0 auto; }

.back-link {
  display: inline-block;
  margin-bottom: 16px;
  font-size: 0.85rem;
  color: var(--ink-light);
}

.detail-title {
  font-family: var(--font-body);
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 12px;
}
.detail-title .title-en {
  display: block;
  font-size: 1rem;
  font-weight: 400;
  color: var(--ink-light);
  margin-top: 4px;
}

.detail-meta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 0.88rem;
  color: var(--ink-light);
  margin-bottom: 12px;
}

.detail-tags { margin-bottom: 12px; display: flex; gap: 6px; flex-wrap: wrap; }

.detail-links {
  display: flex;
  gap: 12px;
  margin-bottom: 24px;
}
.ext-link {
  padding: 6px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.85rem;
  color: var(--ink-light);
}
.ext-link:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

/* ── Summary Sections ───────────────────────────────────────────── */
.summary-section {
  margin-bottom: 24px;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.summary-section h2 {
  font-family: var(--font-body);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--accent);
}

.summary-section p {
  font-size: 0.92rem;
  line-height: 1.8;
}

.one-line {
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.6;
}

.abstract-section { background: #faf8f5; }
.abstract-en { font-size: 0.9rem; color: var(--ink-light); font-style: italic; }

/* ── Summary Placeholders ───────────────────────────────────────── */
.summary-placeholder {
  padding: 24px;
  text-align: center;
  border-radius: var(--radius);
  margin-bottom: 24px;
}
.summary-placeholder.processing { background: #e3f2fd; }
.summary-placeholder.failed { background: #fce4ec; }
.summary-placeholder.none { background: #f5f5f5; }
.error-detail { font-size: 0.85rem; color: #c62828; margin-top: 8px; }

.quality-warning {
  padding: 10px 16px;
  background: #fff8e1;
  border: 1px solid #ffe082;
  border-radius: var(--radius);
  font-size: 0.85rem;
  color: #f57f17;
  margin-bottom: 16px;
}

/* ── Footer ─────────────────────────────────────────────────────── */
.site-footer {
  margin-top: 48px;
  padding: 20px;
  text-align: center;
  font-size: 0.8rem;
  color: var(--ink-light);
  border-top: 1px solid var(--border);
}

/* ── Responsive ─────────────────────────────────────────────────── */
@media (max-width: 640px) {
  .container { padding: 16px; }
  .nav-bar { padding: 10px 16px; }
  .date-nav { gap: 8px; }
  .date-title { font-size: 1.2rem; }
  .paper-card { padding: 14px 16px; }
  .detail-title { font-size: 1.3rem; }
  .detail-meta { flex-direction: column; gap: 4px; }
}