/* ==========================================================
   素粒子物理学入門 共通スタイルシート
   東京理科大学 先進工学部 マテリアル創成工学科
   ========================================================== */
:root {
  --text: #1a202c;
  --text-muted: #4a5568;
  --bg: #fdfdfc;
  --accent: #0e6b7b;          /* 見出し・リンクの基調色(深い青緑・鉄御納戸) */
  --accent-light: #e8f3f5;
  --rule: #d5dbdb;

  --def-border: #0e6b7b;      /* 定義: 青緑 */
  --def-bg: #eaf4f6;
  --thm-border: #14684a;      /* 定理: 緑 */
  --thm-bg: #eff7f3;
  --derive-border: #1a5276;   /* 導出: 青 */
  --derive-bg: #eef4f9;
  --note-border: #b9770e;     /* 数学ノート: 琥珀 */
  --note-bg: #fdf8ee;
  --phys-border: #b03a2e;     /* 物理的意味: 赤茶 */
  --phys-bg: #fdf3f1;
  --why-border: #553c8b;      /* なぜ?/直感: 菫 */
  --why-bg: #f3f0fa;
  --warn-border: #a04000;     /* 注意・よくある誤解: 橙 */
  --warn-bg: #fdf2ec;
  --ex-border: #566573;       /* 例・演習: 灰 */
  --ex-bg: #f4f6f6;
  --code-bg: #2c3e50;
  --keyeq-bg: #fffbea;
  --keyeq-border: #f1c40f;
}

* { box-sizing: border-box; }

html { font-size: 16px; scroll-behavior: smooth; }

body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Hiragino Mincho ProN", "Yu Mincho", "YuMincho", "Noto Serif JP", serif;
  line-height: 1.9;
  text-align: justify;
}

/* ---------- ヘッダー・ナビゲーション ---------- */
header.site {
  background: var(--accent);
  color: #fff;
  padding: 0.6rem 1.2rem;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  position: sticky;
  top: 0;
  z-index: 10;
}
header.site a { color: #fff; text-decoration: none; }
header.site a:hover { text-decoration: underline; }
header.site .series { font-size: 0.9rem; opacity: 0.9; }

nav.pager {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin: 2.5rem auto 1rem;
  max-width: 900px;
  padding: 0 1.2rem;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.95rem;
}
nav.pager a {
  color: var(--accent);
  text-decoration: none;
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 0.5rem 0.9rem;
  background: #fff;
  max-width: 45%;
}
nav.pager a:hover { background: var(--accent-light); }
nav.pager .spacer { flex: 1; }

/* ---------- 本文レイアウト ---------- */
main {
  max-width: 900px;
  margin: 0 auto;
  padding: 1rem 1.2rem 4rem;
}

h1 {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 1.9rem;
  color: var(--accent);
  border-bottom: 3px solid var(--accent);
  padding-bottom: 0.4rem;
  margin: 1.8rem 0 0.6rem;
  line-height: 1.4;
}
h1 .chapter-no {
  display: block;
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: normal;
  letter-spacing: 0.08em;
}

h2 {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 1.45rem;
  color: var(--accent);
  border-left: 6px solid var(--accent);
  padding-left: 0.6rem;
  margin: 2.8rem 0 1rem;
  line-height: 1.45;
  scroll-margin-top: 4rem;
}

h3 {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 1.15rem;
  color: var(--text);
  margin: 2.2rem 0 0.8rem;
  scroll-margin-top: 4rem;
}

p { margin: 0.9rem 0; }

a { color: var(--accent); }

em.term { font-style: normal; font-weight: bold; }

ul, ol { padding-left: 1.5rem; }
li { margin: 0.3rem 0; }

/* 章の導入文 */
.lead {
  background: var(--accent-light);
  border-radius: 8px;
  padding: 1rem 1.3rem;
  margin: 1.4rem 0 2rem;
}
.lead p { margin: 0.5rem 0; }

/* この章で学ぶこと */
.goals {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.95rem;
}
.goals ul { margin: 0.4rem 0 0.2rem; padding-left: 1.4rem; }

/* 前提知識 */
.prereq {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.9rem;
  color: var(--text-muted);
  border-top: 1px dashed var(--rule);
  margin-top: 0.8rem;
  padding-top: 0.6rem;
}

/* 章内目次 */
nav.chapter-toc {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.92rem;
  border: 1px solid var(--rule);
  border-radius: 8px;
  background: #fff;
  padding: 0.8rem 1.2rem;
  margin: 1.5rem 0 2rem;
}
nav.chapter-toc strong { color: var(--accent); display: block; margin-bottom: 0.3rem; }
nav.chapter-toc ol { margin: 0.2rem 0; padding-left: 1.3rem; }
nav.chapter-toc li { margin: 0.15rem 0; }
nav.chapter-toc a { text-decoration: none; }
nav.chapter-toc a:hover { text-decoration: underline; }

/* ---------- ボックス類 ---------- */
.box {
  border-left: 5px solid;
  border-radius: 0 8px 8px 0;
  padding: 0.9rem 1.2rem;
  margin: 1.6rem 0;
}
.box > .box-title {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-weight: bold;
  font-size: 0.98rem;
  margin: 0 0 0.5rem;
}
.box p:last-child { margin-bottom: 0.2rem; }

.def    { border-color: var(--def-border);    background: var(--def-bg); }
.def    > .box-title { color: var(--def-border); }
.thm    { border-color: var(--thm-border);    background: var(--thm-bg); }
.thm    > .box-title { color: var(--thm-border); }
.derive { border-color: var(--derive-border); background: var(--derive-bg); }
.derive > .box-title { color: var(--derive-border); }
.note   { border-color: var(--note-border);   background: var(--note-bg); }
.note   > .box-title { color: var(--note-border); }
.phys   { border-color: var(--phys-border);   background: var(--phys-bg); }
.phys   > .box-title { color: var(--phys-border); }
.why    { border-color: var(--why-border);    background: var(--why-bg); }
.why    > .box-title { color: var(--why-border); }
.warn   { border-color: var(--warn-border);   background: var(--warn-bg); }
.warn   > .box-title { color: var(--warn-border); }
.ex     { border-color: var(--ex-border);     background: var(--ex-bg); }
.ex     > .box-title { color: var(--ex-border); }

/* 重要式(最重要結果)の強調 */
.keyeq {
  background: var(--keyeq-bg);
  border: 1.5px solid var(--keyeq-border);
  border-radius: 8px;
  padding: 0.6rem 1rem;
  margin: 1.6rem 0;
  overflow-x: auto;
}

/* ---------- 数式まわり ---------- */
mjx-container[jax="CHTML"][display="true"] {
  margin: 1rem 0 !important;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 2px 0;
}

/* ---------- コード ---------- */
pre {
  background: var(--code-bg);
  color: #ecf0f1;
  border-radius: 8px;
  padding: 0.9rem 1.1rem;
  overflow-x: auto;
  font-family: "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;
  font-size: 0.86rem;
  line-height: 1.6;
  margin: 1.2rem 0;
  text-align: left;
}
pre .cmt { color: #95a5a6; }
pre .prompt { color: #58d68d; }
code {
  font-family: "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;
  font-size: 0.88em;
  background: #eef1f2;
  border-radius: 4px;
  padding: 0.05em 0.35em;
}
pre code { background: none; padding: 0; font-size: 1em; color: inherit; }

.codecap {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin: -0.8rem 0 1.2rem;
  text-align: left;
}

/* ---------- 表 ---------- */
table {
  border-collapse: collapse;
  margin: 1.4rem auto;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.95rem;
}
caption {
  caption-side: top;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
  text-align: left;
}
th, td {
  border: 1px solid var(--rule);
  padding: 0.45rem 0.9rem;
}
th { background: var(--accent-light); color: var(--accent); }
td { background: #fff; }
.tablewrap { overflow-x: auto; margin: 1.4rem 0; }
.tablewrap table { margin: 0 auto; }

/* ---------- 図 ---------- */
figure {
  margin: 1.8rem auto;
  text-align: center;
}
figure svg { max-width: 100%; height: auto; }
figcaption {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
  text-align: center;
}

/* ---------- 目次ページ ---------- */
.toc-part {
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  color: var(--accent);
  font-size: 1.2rem;
  margin: 2.2rem 0 0.6rem;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 0.25rem;
}
ol.toc { list-style: none; padding: 0; margin: 0.6rem 0; }
ol.toc li {
  margin: 0.55rem 0;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
}
ol.toc li a {
  display: block;
  text-decoration: none;
  padding: 0.7rem 1rem;
  border: 1px solid var(--rule);
  border-radius: 8px;
  background: #fff;
  color: var(--text);
}
ol.toc li a:hover { background: var(--accent-light); }
ol.toc .ch-no {
  color: var(--accent);
  font-weight: bold;
  margin-right: 0.6rem;
}
ol.toc .ch-desc {
  display: block;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

/* ---------- 脚注・参考 ---------- */
.refs {
  font-size: 0.92rem;
  color: var(--text-muted);
  border-top: 1px solid var(--rule);
  margin-top: 3rem;
  padding-top: 1rem;
}
.refs ol { padding-left: 1.4rem; }

/* ---------- 印刷 ---------- */
@media print {
  header.site, nav.pager, nav.chapter-toc { display: none; }
  body { background: #fff; }
  main { max-width: 100%; }
  .box { break-inside: avoid; }
  pre { background: #f4f6f6; color: #1a202c; border: 1px solid var(--rule); }
}

@media (max-width: 640px) {
  html { font-size: 15px; }
  h1 { font-size: 1.55rem; }
  h2 { font-size: 1.25rem; }
  body { text-align: left; }
  nav.pager { flex-direction: column; }
  nav.pager a { max-width: 100%; }
}