/* 弘道塾 AI学習コラム共通CSS | 数学・物理・化学
   style.css の後に読み込む。記事の最外側は .ai-column-article。
   旧 .ai-math-* クラスは使用しない。 */

.ai-column-article {
  --ai-accent: #2471bd;
  --ai-dark: #062852;
  --ai-heading: #173b62;
  --ai-muted: #526578;
  --ai-border: #d2dfed;
  max-width: 780px;
  min-width: 0;
  margin: 0 auto;
  color: #344454;
  overflow-wrap: break-word;
}
.ai-column-article *,
.ai-column-article *::before,
.ai-column-article *::after { box-sizing: border-box; }
.ai-column-article a { text-underline-offset: 3px; }
.ai-column-article strong { color: var(--ai-heading); font-weight: 700; }

/* タイトル・執筆者 */
.ai-column-hero { margin: 0 0 30px; }
.ai-column-kicker { display: inline-block; margin-bottom: 12px; color: var(--ai-muted); font-size: 12.5px; font-weight: 700; letter-spacing: .04em; }
.ai-column-hero .hero-title {
  margin: 0 0 18px;
  padding-left: 15px;
  border-left: 4px solid var(--ai-accent);
  color: var(--ai-dark);
  font-size: 25px;
  line-height: 1.6;
}
.ai-column-author { margin: 0; color: #65717d; font-size: 12.5px; line-height: 1.8; }
.ai-column-author strong { color: #334d66; }

/* 本文と見出し：長い区切り線を使わず、左線で階層を示す */
.ai-column-body { color: #444; font-size: 14.5px; line-height: 1.95; overflow-wrap: anywhere; }
.ai-column-body p { margin: 0 0 18px; }
.ai-column-body .ai-column-section { margin: 0 0 39px; padding: 0; border: 0; }
.ai-column-body .ai-column-section:last-child { margin-bottom: 0; }
.ai-column-body .ai-column-section > h2.section-title,
.ai-column-body .ai-column-section > h2 {
  margin: 0 0 23px;
  padding: 2px 0 2px 13px;
  border: 0;
  border-left: 3px solid var(--ai-accent);
  background: transparent;
  color: var(--ai-dark);
  font-size: 19px;
  line-height: 1.65;
  font-weight: 700;
}
.ai-column-body .ai-column-section h3,
.ai-column-body .ai-column-subheading {
  margin: 27px 0 13px;
  color: var(--ai-heading);
  font-size: 16px;
  line-height: 1.7;
  font-weight: 700;
}
.ai-column-body .ai-column-section > h3:first-child { margin-top: 0; }
.ai-column-body .ai-column-section > :last-child { margin-bottom: 0; }

/* 冒頭3ブロックの結論 */
.ai-column-keypoint {
  margin: 20px 0 22px;
  padding: 14px 18px;
  border-left: 3px solid var(--ai-accent);
  background: #f5f9fd;
}
.ai-column-keypoint p { margin: 0; color: var(--ai-heading); font-size: 14.5px; font-weight: 700; line-height: 1.8; }
.ai-column-keypoint .ai-column-keypoint-note { margin-top: 6px; color: var(--ai-muted); font-size: 13px; font-weight: 400; }

/* 補足・手順 */
.ai-column-subsection { margin: 24px 0 0; padding-top: 15px; border-top: 1px solid var(--ai-border); }
.ai-column-subsection > h3 { margin: 0 0 12px !important; font-size: 15.5px !important; }
.ai-column-subsection p { margin-bottom: 13px; }
.ai-column-note { margin: 12px 0 18px; color: #667582; font-size: 12.5px; line-height: 1.8; }
.ai-column-transition { margin: 20px 0 0; color: var(--ai-muted); font-size: 13.5px; line-height: 1.85; }
.ai-column-body ol, .ai-column-body ul { margin: 12px 0 21px; padding-left: 1.7em; }
.ai-column-body li { margin-bottom: 7px; padding-left: 2px; }
.ai-column-steps { margin: 17px 0 22px !important; padding-left: 1.8em !important; }
.ai-column-steps li { margin-bottom: 7px; line-height: 1.8; }
.ai-column-steps li::marker { color: #315e87; font-weight: 700; }

/* 例題 */
.ai-column-problem {
  margin: 19px 0;
  padding: 16px 19px;
  border: 1px solid var(--ai-border);
  border-radius: 5px;
  background: rgba(255,255,255,.68);
}
.ai-column-problem-label { margin: 0 0 9px !important; color: var(--ai-heading); font-size: 12.5px; font-weight: 700; }
.ai-column-problem p { margin-bottom: 10px; }
.ai-column-problem p:last-child { margin-bottom: 0; }

/* AIへの質問例：問題文とは違う淡い青色 */
.ai-column-prompt {
  margin: 17px 0;
  padding: 14px 18px;
  border: 0;
  border-left: 3px solid #8eafce;
  border-radius: 0 4px 4px 0;
  background: #f2f7fd;
  color: #34495e;
  font-size: 14px;
  line-height: 1.85;
  font-style: normal;
}
.ai-column-prompt-label { display: block; margin-bottom: 6px; color: #526b82; font-size: 12px; font-weight: 700; }

/* 数式 */
.ai-column-equation { max-width: 100%; margin: 12px 0 16px; overflow-x: auto; overflow-y: hidden; text-align: center; -webkit-overflow-scrolling: touch; }
.ai-column-equation mjx-container[display="true"] { margin: .55em 0 !important; }
.ai-column-problem .ai-column-equation { margin: 10px 0; }

/* 解答：初期状態はPHPのdetailsにopenを付けず閉じる */
.ai-column-solution { margin: 17px 0 22px; border: 1px solid #cad9e8; border-radius: 6px; background: rgba(255,255,255,.58); overflow: hidden; }
.ai-column-solution > summary {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 13px 17px; cursor: pointer; list-style: none;
  color: #17466f; font-size: 14px; font-weight: 700; line-height: 1.65;
}
.ai-column-solution > summary::-webkit-details-marker { display: none; }
.ai-column-solution > summary::after { content: "＋"; flex: 0 0 auto; font-size: 18px; font-weight: 400; }
.ai-column-solution[open] > summary::after { content: "－"; }
.ai-column-solution[open] > summary { border-bottom: 1px solid var(--ai-border); }
.ai-column-solution > summary:hover { background: #f2f7fd; }
.ai-column-solution > summary:focus-visible { outline: 2px solid var(--ai-accent); outline-offset: -3px; }
.ai-column-solution-body { padding: 13px 19px 17px; font-size: 13.5px; line-height: 1.75; }
.ai-column-solution-body p { margin: 0 0 9px; }
.ai-column-solution-body p:last-child { margin-bottom: 0; }
.ai-column-solution-body .ai-column-equation { margin: 8px 0 11px; }
.ai-column-solution-body .ai-column-equation mjx-container[display="true"] { margin: .4em 0 !important; }

/* 解説後の確認：結論より強い区切り */
.ai-column-checkpoint {
  margin: 26px 0 13px;
  padding: 18px 21px;
  border: 0;
  border-top: 3px solid var(--ai-accent);
  background: rgba(255,255,255,.48);
}
.ai-column-body .ai-column-checkpoint > h3 { margin: 0 0 12px; color: var(--ai-dark); font-size: 17px; }
.ai-column-checkpoint p { margin-bottom: 11px; }
.ai-column-checkpoint ul, .ai-column-checkpoint ol { margin: 10px 0 13px; padding-left: 1.6em; }
.ai-column-checkpoint li { margin-bottom: 5px; }
.ai-column-checkpoint p:last-child { margin-bottom: 0; }

/* 対処表 */
.ai-column-guide-table { width: 100%; margin: 18px 0 22px; border-collapse: collapse; font-size: 13.5px; line-height: 1.75; }
.ai-column-guide-table th, .ai-column-guide-table td { padding: 11px 13px; border-bottom: 1px solid var(--ai-border); text-align: left; vertical-align: top; }
.ai-column-guide-table thead th { color: var(--ai-heading); background: #dfeaf5; font-weight: 700; }
.ai-column-guide-table tbody td:first-child { width: 40%; color: #334d66; font-weight: 600; }

/* 最終結論 */
.ai-column-conclusion { margin: 22px 0; padding: 19px 21px; border-left: 4px solid var(--ai-accent); background: #f4f8fd; }
.ai-column-conclusion p { margin: 0; color: var(--ai-dark); font-size: 16px; line-height: 1.8; font-weight: 700; }

/* 関連ページ・末尾 */
.ai-column-related { margin: 40px 0 20px; padding-top: 23px; border-top: 1px solid var(--ai-border); }
.ai-column-related .advice-list-group { margin-top: 12px; }
.ai-column-related .advice-list-item { min-width: 0; }
.ai-column-related .advice-text-main { overflow-wrap: anywhere; }
.ai-column-related-list { margin: 0; padding-left: 1.4em; }
.ai-column-related-list li { margin-bottom: 9px; }
.ai-column-footer-note { margin-top: 27px; padding-top: 15px; border-top: 1px solid var(--ai-border); color: #65717d; font-size: 12.5px; line-height: 1.85; }
.ai-column-footer-note a { color: #315e87; text-underline-offset: 3px; }

@media (max-width: 767px) {
  .ai-column-hero { margin-bottom: 26px; }
  .ai-column-hero .hero-title { font-size: 21px; padding-left: 12px; }
  .ai-column-body { font-size: 14px; line-height: 1.9; }
  .ai-column-body p { margin-bottom: 16px; }
  .ai-column-body .ai-column-section { margin-bottom: 33px; }
  .ai-column-body .ai-column-section > h2.section-title,
  .ai-column-body .ai-column-section > h2 { font-size: 18px; margin-bottom: 19px; padding-left: 11px; }
  .ai-column-body .ai-column-section h3 { font-size: 15px; }
  .ai-column-keypoint { padding: 12px 14px; margin: 17px 0 19px; }
  .ai-column-keypoint p { font-size: 14px; }
  .ai-column-keypoint .ai-column-keypoint-note { font-size: 12.5px; }
  .ai-column-problem { padding: 14px; }
  .ai-column-prompt { padding: 12px 14px; font-size: 13.5px; }
  .ai-column-solution > summary { padding: 12px 14px; font-size: 13.5px; }
  .ai-column-solution-body { padding: 12px 14px 15px; font-size: 13px; }
  .ai-column-checkpoint { padding: 16px 14px; }
  .ai-column-body .ai-column-checkpoint > h3 { font-size: 16px; }
  .ai-column-guide-table { font-size: 12.5px; }
  .ai-column-guide-table th, .ai-column-guide-table td { padding: 10px 8px; }
  .ai-column-conclusion { padding: 16px; }
  .ai-column-conclusion p { font-size: 15px; }
}

@media print {
  .ai-column-article { color: #000; }
  .ai-column-keypoint, .ai-column-problem, .ai-column-prompt,
  .ai-column-checkpoint, .ai-column-conclusion { break-inside: avoid; }
  .ai-column-solution { break-inside: auto; }
  /* 印刷時の解答表示はdetailsのopen状態に依存する。 */
}