/* 轻量中文排版与主题微调 */
html { font-size: 16px; }
body { line-height: 1.75; color: #222; }

.site-hero {
  background: linear-gradient(135deg, #f8f9fa, #ffffff);
  border-bottom: 1px solid #eee;
}

.book-card p { min-height: 3.5em; }

.content-max { max-width: 960px; }

.section-title { font-weight: 700; letter-spacing: .02em; }

/* 题目与答案展示 */
.question-card { border-left: 4px solid #0d6efd; }
details.answer { background: #f8f9fa; border-radius: .5rem; padding: .5rem .75rem; }
details.answer[open] { border: 1px solid #e9ecef; }

/* 小屏优化 */
@media (max-width: 576px) {
  .book-card p { min-height: initial; }
}

/* 导读页美化（简约大气） */
.guide-content { --accent: #0d6efd; }
.guide-kicker { color: var(--accent); text-transform: uppercase; letter-spacing: .08em; font-weight: 600; font-size: .8rem; }
.guide-content h2, .guide-content h3, .guide-content h4 { scroll-margin-top: 90px; }
.guide-content h4 { border-bottom: 1px solid #eef2f6; padding-bottom: .25rem; margin-top: 1.5rem; }
.guide-toc .nav-link { border-radius: 999px; }
.soft-card { background: #fff; border: 1px solid #f1f3f5; border-radius: .75rem; padding: 1rem; box-shadow: 0 1px 2px rgba(16,24,40,.04); }
.table thead th { background: #f8fafc; }