:root {
    --text: #3a352d;
    --muted: #7d756a;
    --bg: #f4efe5;
    --accent: #c05f42;
    --border: #ddd3c2;
    --note-bg: #ece5d6;
  }
  * { box-sizing: border-box; }
  body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.85;
    font-size: 16px;
  }
  header.site {
    border-bottom: 1px solid var(--border);
    padding: 3.2rem 1.2rem 2.4rem;
    text-align: center;
  }
  header.site img.logo { width: 96px; height: 96px; border-radius: 22px; margin-bottom: 1.1rem; }
  header.site h1 { margin: 0 0 .4rem; font-size: 1.9rem; letter-spacing: .02em; }
  header.site p { margin: 0; color: var(--muted); }
  main { max-width: 760px; margin: 0 auto; padding: 1.5rem 1.2rem 4rem; }
  nav.toc {
    background: var(--note-bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1rem 1.4rem;
    margin: 1.5rem 0 2.5rem;
  }
  nav.toc strong { display: block; margin-bottom: .3rem; }
  nav.toc ul { margin: 0; padding-left: 1.3rem; }
  nav.toc a { color: var(--accent); text-decoration: none; }
  nav.toc a:hover { text-decoration: underline; }
  section { margin-top: 3.5rem; }
  h2 {
    font-size: 1.45rem;
    border-bottom: 2px solid var(--border);
    padding-bottom: .35rem;
    margin: 0 0 1.2rem;
    scroll-margin-top: 1rem;
  }
  h3 { font-size: 1.15rem; margin: 2.2rem 0 .6rem; }
  h4 { font-size: 1rem; margin: 1.8rem 0 .5rem; }
  p { margin: .7rem 0; }
  ol, ul { padding-left: 1.5rem; }
  li { margin: .25rem 0; }
  strong { font-weight: 700; }
  blockquote {
    margin: 1rem 0;
    padding: .6rem 1rem;
    background: var(--note-bg);
    border-left: 4px solid var(--accent);
    border-radius: 0 8px 8px 0;
    color: var(--muted);
  }
  blockquote p { margin: .2rem 0; }
  table { border-collapse: collapse; width: 100%; margin: 1rem 0; }
  th, td { border: 1px solid var(--border); padding: .5rem .8rem; text-align: left; }
  th { background: var(--note-bg); }
  .video {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    margin: 1rem 0 1.6rem;
    border-radius: 10px;
    overflow: hidden;
    background: #000;
  }
  .video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
  .notice {
    background: var(--note-bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1.2rem 1.5rem;
    margin: 1rem 0;
  }
  img.section-img {
    display: block;
    max-width: 100%;
    height: auto;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: #fff;
    margin: 1rem 0 1.4rem;
  }
  img.mail-icon { width: 64px; height: 64px; display: block; margin: 0 0 .6rem; }
  hr { border: none; border-top: 1px solid var(--border); margin: 3rem 0; }
  footer {
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--muted);
    padding: 2rem 1rem;
    font-size: .9rem;
  }
  a { color: var(--accent); }
  code { background: var(--note-bg); padding: .1em .35em; border-radius: 4px; font-size: .95em; }
  @media (prefers-color-scheme: dark) {
    :root {
      --text: #e8e2d6;
      --muted: #a39a8c;
      --bg: #211e18;
      --accent: #e2916f;
      --border: #3a352b;
      --note-bg: #2b2720;
    }
  }

  nav.lang {
    text-align: right;
    max-width: 760px;
    margin: -2rem auto 1.2rem;
    font-size: .88rem;
    color: var(--muted);
  }
  nav.lang a { text-decoration: none; }
  nav.lang span { font-weight: 700; color: var(--text); }

  /* RTL (Arabic) */
  [dir="rtl"] blockquote {
    border-left: none;
    border-right: 4px solid var(--accent);
    border-radius: 8px 0 0 8px;
  }
  [dir="rtl"] nav.toc ul, [dir="rtl"] ol, [dir="rtl"] ul {
    padding-left: 0;
    padding-right: 1.5rem;
  }
  [dir="rtl"] nav.lang { text-align: left; }
  [dir="rtl"] th, [dir="rtl"] td { text-align: right; }