/* ==========================================================================
   子页面样式 - help.html / knowledge.html
   ========================================================================== */

.page-content {
  max-width: 900px;
}

.page-header {
  text-align: center;
  padding: 32px 16px 24px;
}

.page-header h1 {
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
  background: linear-gradient(135deg, var(--text), var(--accent) 50%, var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.page-sub {
  font-size: 16px;
  color: var(--muted);
  margin: 0;
}

.lang-hint {
  font-size: 12px;
  color: var(--muted);
  margin-top: 12px;
  opacity: 0.7;
}

/* 目录 TOC */
.toc {
  padding: 20px 24px;
  margin-bottom: 24px;
  border-radius: var(--radius-lg);
}

.toc h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin: 0 0 12px;
}

.toc ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 8px;
}

.toc a {
  display: block;
  padding: 8px 12px;
  border-radius: 8px;
  color: var(--text-2);
  font-size: 14px;
  transition: all 0.15s;
}

.toc a:hover {
  background: var(--glass-soft);
  color: var(--accent);
  transform: translateX(2px);
}

/* 帮助卡片 */
.help-card {
  padding: 28px 32px;
  margin-bottom: 20px;
  border-radius: var(--radius-lg);
}

.help-card h2 {
  font-size: 22px;
  margin: 0 0 12px;
  color: var(--text);
}

.help-card h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--accent);
  margin: 20px 0 10px;
}

.help-card p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-2);
  margin-bottom: 12px;
}

.help-card ul,
.help-card ol {
  font-size: 14px;
  line-height: 1.9;
  color: var(--text-2);
  padding-left: 24px;
  margin-bottom: 12px;
}

.help-card li {
  margin-bottom: 6px;
}

.help-card code {
  background: var(--glass);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'SF Mono', 'Monaco', monospace;
  font-size: 13px;
  color: var(--accent);
}

.help-card strong {
  color: var(--text);
}

/* FAQ items */
.faq-item {
  margin-bottom: 12px;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  background: var(--surface);
  overflow: hidden;
}

.faq-item summary {
  cursor: pointer;
  padding: 14px 18px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  user-select: none;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: background 0.15s;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::before {
  content: "▸";
  color: var(--accent);
  font-size: 11px;
  transition: transform 0.2s;
  flex-shrink: 0;
}

.faq-item[open] summary::before {
  transform: rotate(90deg);
}

.faq-item summary:hover {
  background: var(--glass-soft);
}

.faq-item p {
  padding: 0 18px 16px;
  margin: 0;
  color: var(--text-2);
  font-size: 13px;
  line-height: 1.8;
}

/* 术语表（Glossary） */
.glossary {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 10px 20px;
}

.glossary dt {
  font-weight: 700;
  color: var(--accent);
  font-size: 14px;
  padding: 6px 0;
}

.glossary dd {
  margin: 0;
  font-size: 13px;
  color: var(--text-2);
  line-height: 1.7;
  padding: 6px 0;
}

/* 返回首页按钮 */
.back-home {
  text-align: center;
  padding: 32px 0 16px;
}

.back-home .btn {
  display: inline-flex;
}

/* 响应式 */
@media (max-width: 768px) {
  .help-card {
    padding: 20px 16px;
  }

  .glossary {
    grid-template-columns: 1fr;
  }

  .toc ul {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .toc ul {
    grid-template-columns: 1fr;
  }

  .help-card h2 {
    font-size: 18px;
  }

  .help-card h3 {
    font-size: 14px;
  }
}