.graph-entry { display: flex; align-items: center; gap: 14px; margin: 18px 0 0; padding: 14px 18px 14px 14px; border: 1px solid #cfe3de; border-radius: 18px; background: linear-gradient(100deg, #eef8f5 0%, var(--paper) 62%); box-shadow: 0 18px 40px -32px rgba(20, 60, 55, .35); transition: border-color .2s, box-shadow .2s; }
.graph-entry + .graph-entry { margin-top: 10px; }
.graph-entry:hover { border-color: #9fd0c6; box-shadow: 0 18px 36px -24px rgba(8, 127, 121, .45); }
.graph-entry:focus-visible { outline: 3px solid #82cfc7; outline-offset: 2px; }
.graph-icon { display: grid; flex: none; place-items: center; width: 52px; height: 52px; border: 1px solid #cfe3de; border-radius: 14px; background: var(--paper); color: var(--teal); }
.graph-text { display: grid; gap: 2px; min-width: 0; }
.graph-title { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; color: var(--ink); font-size: 17px; font-weight: 750; }
.graph-tag { padding: 1px 8px; border-radius: 999px; background: var(--teal-soft); color: var(--teal-dark); font-size: 12px; font-weight: 600; }
.graph-desc { color: var(--muted); font-size: 13.5px; }
.graph-desc b { margin: 0 1px; color: var(--teal); font-weight: 750; font-variant-numeric: tabular-nums; }
.graph-go { display: inline-flex; flex: none; align-items: center; gap: 4px; margin-left: auto; padding: 7px 12px 7px 14px; border: 1px solid var(--teal); border-radius: 999px; color: var(--teal-dark); font-size: 13.5px; font-weight: 600; transition: background .15s, color .15s, transform .15s; }
.graph-entry:hover .graph-go { background: var(--teal); color: #fff; transform: translateX(2px); }

.chapter-heading { margin-bottom: 16px; }
.chapter-book { margin: 0 0 2px; color: var(--muted); font-size: 13px; letter-spacing: .04em; }

.topic-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.topic-card { display: flex; flex-direction: column; padding: 20px 22px 18px; border: 1px solid var(--line); border-radius: 18px; background: var(--paper); box-shadow: 0 18px 40px -32px rgba(20, 60, 55, .35); transition: border-color .2s, box-shadow .2s; }
.topic-card:hover { border-color: #9fd0c6; box-shadow: 0 18px 36px -24px rgba(8, 127, 121, .45); }
.topic-top { display: flex; align-items: center; gap: 8px; }
.topic-no { padding: 4px 8px; border-radius: 8px; background: var(--teal-soft); color: var(--teal); font: 600 12px/1 ui-monospace, "SF Mono", Menlo, Consolas, monospace; letter-spacing: .04em; }
.topic-sec { color: var(--faint); font-size: 12px; font-variant-numeric: tabular-nums; }
.topic-new { margin-left: auto; padding: 1px 8px; border-radius: 999px; background: #fdf1dc; color: #b06f05; font-size: 12px; font-weight: 700; }
.topic-card h3 { margin: 12px 0 0; font-size: 20px; line-height: 1.4; font-weight: 750; }
.topic-card h3 a:hover { color: var(--teal); }
.topic-desc { margin: 4px 0 0; color: var(--muted); font-size: 14px; }
.topic-formula { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 8px; margin: 14px 0 0; padding: 8px 12px; border-radius: 12px; background: #f7faf9; color: var(--ink); }
.topic-formula math { font-family: var(--math); font-size: 17px; math-style: normal; }
.topic-label { margin: 14px 0 6px; color: var(--muted); font-size: 12px; font-weight: 600; letter-spacing: .06em; }
.topic-methods { display: flex; flex-wrap: wrap; gap: 6px; margin: 0; padding: 0; list-style: none; }
.topic-methods a { display: inline-block; padding: 4px 10px; border: 1px solid #cfe3de; border-radius: 999px; color: var(--teal-dark); font-size: 13px; font-weight: 600; transition: background .15s, color .15s, border-color .15s; }
.topic-methods a:hover { border-color: var(--teal); background: var(--teal); color: #fff; }
.topic-methods .soon a { border-style: dashed; border-color: #cfdcd7; color: var(--faint); font-weight: 500; }
.topic-methods .soon a::after { content: " · 准备中"; font-size: 11px; }
.topic-foot { display: flex; align-items: center; gap: 10px; margin-top: auto; padding-top: 16px; }
.topic-count { color: var(--muted); font-size: 13px; }
.topic-count b { margin-right: 2px; color: var(--teal); font-size: 20px; font-weight: 750; font-variant-numeric: tabular-nums; }
.topic-ai { padding: 2px 8px; border-radius: 999px; background: var(--teal-soft); color: var(--teal-dark); font-size: 12px; font-weight: 600; }
.topic-go { display: inline-flex; align-items: center; gap: 4px; margin-left: auto; padding: 7px 12px 7px 14px; border-radius: 999px; background: var(--teal); color: #fff; font-size: 13.5px; font-weight: 600; transition: background .15s, transform .15s; }
.topic-go:hover { background: var(--teal-dark); transform: translateX(2px); }


.topic-more { margin: 16px 0 0; padding: 14px 18px; border: 1px dashed #cfdcd7; border-radius: 16px; background: #fafcfb; color: var(--faint); font-size: 13px; text-align: center; }

@media (max-width: 720px) {
  .topic-grid { grid-template-columns: 1fr; }
  .topic-card { padding: 16px 16px 14px; border-radius: 16px; }
  .topic-card h3 { font-size: 18px; }
  .graph-entry { gap: 12px; padding: 12px 14px 12px 12px; border-radius: 16px; }
  .graph-icon { width: 44px; height: 44px; border-radius: 12px; }
  .graph-icon svg { width: 28px; height: 28px; }
  .graph-go { padding: 7px; font-size: 0; }
}
@media (prefers-reduced-motion: reduce) {
  .topic-go, .graph-go { transition: none; }
  .topic-go:hover, .graph-entry:hover .graph-go { transform: none; }
}