/* =====================================================
   article.css — 記事ページ共通スタイル
   テニス革命 | https://tennis.nekonikoban.org/
   ===================================================== */

/* ----- ARTICLE HERO ----- */
.article-hero {
  background: linear-gradient(135deg, #0d5c44, #1a7a5e, #239270);
  padding: 60px 24px 70px;
  position: relative;
  overflow: hidden;
}
.article-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='80' height='80' viewBox='0 0 80 80' xmlns='http://www.w3.org/2000/svg'%3E%3Ccircle cx='40' cy='40' r='30' stroke='%23ffffff' stroke-width='1' stroke-opacity='.05' fill='none'/%3E%3C/svg%3E") center/80px;
}
.hero-inner { max-width: 860px; margin: 0 auto; position: relative; }
.article-cats { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 18px; }
.article-cat {
  display: inline-block;
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .06em;
  padding: 4px 14px;
  border-radius: 100px;
  background: rgba(255,255,255,.15);
  border: 1px solid rgba(255,255,255,.3);
  color: rgba(255,255,255,.9);
}
.article-cat.key { background: var(--primary-light); border-color: var(--primary-light); }
.article-cat.hot { background: var(--accent); border-color: var(--accent); }
.article-hero h1 {
  font-size: clamp(1.4rem, 3.5vw, 2.2rem);
  font-weight: 900;
  color: white;
  line-height: 1.4;
  letter-spacing: .02em;
  margin-bottom: 16px;
  text-shadow: 0 2px 12px rgba(0,0,0,.2);
}
.article-hero h1 em { font-style: normal; color: #ffd86e; }
.article-meta {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: .78rem;
  color: rgba(255,255,255,.65);
  flex-wrap: wrap;
}
.hero-wave {
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 50px;
}

/* ----- ARTICLE LAYOUT (2-column) ----- */
.article-layout {
  max-width: 1000px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 40px;
  padding: 48px 24px;
}
@media (max-width: 820px) {
  .article-layout { grid-template-columns: 1fr; }
  .sidebar { order: -1; }
}
.article-content { min-width: 0; }

/* ----- TOC ----- */
.toc-box {
  background: var(--bg-pale);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 40px;
}
.toc-title { font-size: .9rem; font-weight: 800; color: var(--text-dark); margin-bottom: 16px; }
.toc-list { list-style: none; }
.toc-list li { margin-bottom: 8px; }
.toc-list a {
  color: var(--primary);
  text-decoration: none;
  font-size: .85rem;
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.5;
}
.toc-list a:hover { text-decoration: underline; }
.toc-list a::before {
  content: '▶';
  font-size: .6rem;
  color: var(--primary-light);
  margin-top: 4px;
  flex-shrink: 0;
}

/* ----- ARTICLE BODY ----- */
.article-body h2 {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-dark);
  margin: 48px 0 20px;
  padding: 16px 20px;
  background: var(--bg-pale);
  border-left: 4px solid var(--primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  line-height: 1.4;
  letter-spacing: .02em;
}
.article-body h2:first-child { margin-top: 0; }
.article-body h3 {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--primary);
  margin: 36px 0 14px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--border);
  letter-spacing: .02em;
}
.article-body h4 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-dark);
  margin: 24px 0 10px;
}
.article-body p {
  font-size: .97rem;
  color: var(--text-mid);
  line-height: 2;
  margin-bottom: 18px;
}
.article-body strong { color: var(--text-dark); font-weight: 700; }
.article-body em { font-style: normal; color: var(--primary); font-weight: 700; }

/* ----- LEAD BOX ----- */
.lead-box {
  background: linear-gradient(135deg, var(--primary-pale), #d4f0e4);
  border: 1px solid #b8ddd0;
  border-radius: var(--radius);
  padding: 28px 32px;
  margin-bottom: 36px;
}
.lead-box p { font-size: 1rem; color: var(--text-dark); margin: 0; line-height: 2; }
.lead-box p + p { margin-top: 14px; }

/* ----- ALERT BOXES ----- */
.alert-box { border-radius: var(--radius); padding: 20px 24px; margin: 28px 0; }
.alert-box.warning { background: #fff9e6; border: 1px solid #ffd86e; border-left: 4px solid #f5a500; }
.alert-box.info    { background: var(--primary-pale); border: 1px solid var(--border); border-left: 4px solid var(--primary); }
.alert-box.danger  { background: #fff0f0; border: 1px solid #ffcccc; border-left: 4px solid #e84444; }
.alert-box.success { background: #f0fff4; border: 1px solid #a8e6c0; border-left: 4px solid #28a745; }
.alert-box.accent  { background: #fff8f0; border: 1px solid #ffe0c3; border-left: 4px solid var(--accent); }
.alert-title { font-size: .85rem; font-weight: 800; margin-bottom: 8px; display: flex; align-items: center; gap: 6px; }
.alert-box p { font-size: .9rem; color: var(--text-dark); margin: 0; line-height: 1.8; }

/* ----- HIGHLIGHT BOX ----- */
.highlight-box {
  background: linear-gradient(135deg, #fff8e6, #fff3d6);
  border: 2px solid #ffd86e;
  border-radius: var(--radius);
  padding: 24px 28px;
  margin: 28px 0;
  text-align: center;
}
.highlight-box .h-title { font-size: 1.1rem; font-weight: 800; color: var(--text-dark); margin-bottom: 12px; }
.highlight-box p { font-size: .92rem; color: var(--text-mid); margin: 0; line-height: 1.9; }

/* ----- BLOCKQUOTE ----- */
blockquote {
  border-left: 4px solid var(--primary-light);
  margin: 20px 0;
  padding: 14px 20px;
  background: var(--primary-pale);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
blockquote p { font-size: .9rem; color: var(--text-dark); margin: 0; font-style: italic; }
blockquote cite { font-size: .78rem; color: var(--text-light); font-style: normal; display: block; margin-top: 6px; }

/* ----- CHECK LIST ----- */
ul.check-list { list-style: none; margin: 16px 0 20px; }
ul.check-list li {
  padding: 8px 0 8px 26px;
  position: relative;
  font-size: .92rem;
  color: var(--text-mid);
  line-height: 1.7;
  border-bottom: 1px dashed var(--border);
}
ul.check-list li:last-child { border-bottom: none; }
ul.check-list li::before { content: '✓'; position: absolute; left: 0; color: var(--primary); font-weight: 800; }

/* ----- CTA BLOCK ----- */
.cta-block {
  background: linear-gradient(135deg, #fff8f0, #fff3e6);
  border: 2px solid #ffe0c3;
  border-radius: var(--radius);
  padding: 36px 32px;
  text-align: center;
  margin: 48px 0;
}
.cta-block .cta-pre { font-size: .8rem; color: var(--accent); font-weight: 700; letter-spacing: .08em; margin-bottom: 10px; }
.cta-block h3 { font-size: 1.3rem; font-weight: 900; color: var(--text-dark); line-height: 1.4; margin-bottom: 14px; letter-spacing: .02em; }
.cta-block h3 strong { color: var(--accent); }
.cta-block p { font-size: .9rem; color: var(--text-mid); line-height: 1.9; margin-bottom: 24px; }
.cta-features { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin-bottom: 28px; }
.cta-feature {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: .8rem;
  font-weight: 600;
  color: var(--text-dark);
  background: white;
  border: 1px solid #ffe0c3;
  padding: 6px 14px;
  border-radius: 100px;
}
.cta-feature::before { content: '✓'; color: var(--accent); font-weight: 800; }
.cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: white;
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 800;
  padding: 18px 40px;
  border-radius: 100px;
  box-shadow: 0 4px 20px rgba(232,118,58,.35);
  transition: all .2s;
  letter-spacing: .02em;
}
.cta-btn:hover { transform: translateY(-2px); box-shadow: 0 8px 28px rgba(232,118,58,.45); }
.cta-note { font-size: .75rem; color: var(--text-light); margin-top: 14px; }

/* ----- SIDEBAR ----- */
.sidebar-widget {
  background: var(--bg-pale);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 20px;
  margin-bottom: 24px;
}
.widget-title {
  font-size: .85rem;
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border);
}
.related-link {
  display: block;
  padding: 10px 0;
  border-bottom: 1px dashed var(--border);
  text-decoration: none;
  font-size: .83rem;
  color: var(--primary);
  line-height: 1.5;
}
.related-link:last-child { border-bottom: none; }
.related-link:hover { text-decoration: underline; }
.related-link::before { content: '→ '; }

.sidebar-cta {
  background: linear-gradient(135deg, #fff8f0, #fff3e6);
  border: 2px solid #ffe0c3;
  border-radius: var(--radius);
  padding: 22px 20px;
  text-align: center;
}
.sidebar-cta .sc-title { font-size: .9rem; font-weight: 800; color: var(--text-dark); margin-bottom: 10px; line-height: 1.5; }
.sidebar-cta .sc-price { font-size: 1.5rem; font-weight: 900; color: var(--accent); margin-bottom: 14px; }
.sidebar-cta .sc-price span { font-size: .8rem; color: var(--text-light); }
.sc-btn {
  display: block;
  background: var(--accent);
  color: white;
  text-decoration: none;
  font-size: .88rem;
  font-weight: 800;
  padding: 14px 20px;
  border-radius: 100px;
  box-shadow: 0 3px 12px rgba(232,118,58,.3);
  transition: all .2s;
  margin-bottom: 10px;
}
.sc-btn:hover { background: var(--accent-light); transform: translateY(-1px); }
.sc-note { font-size: .72rem; color: var(--text-light); line-height: 1.6; }

/* ----- RESPONSIVE ----- */
@media (max-width: 600px) {
  .article-body h2 { font-size: 1.1rem; padding: 12px 14px; }
  .cta-block { padding: 24px 18px; }
}