:root {
      --bg: #f8f6f2;
      --card-bg: #ffffff;
      --text: #333333;
      --text-sub: #888888;
      --accent: #c8946a;
      --border: #e8e0d8;
      --radius: 12px;
    }
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      background: var(--bg);
      color: var(--text);
      font-family: "Hiragino Sans", "Noto Sans JP", sans-serif;
      line-height: 1.9;
      padding: 40px 20px;
    }
    body::before {
      content: "肩の症状を解消する体操";
      display: block;
      text-align: center;
      color: var(--accent);
      font-weight: normal;
      font-size: 2rem;
      margin-bottom: 32px;
    }
    .article {
      max-width: 820px;
      margin: 0 auto;
      background: var(--card-bg);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 32px;
      white-space: pre-line;
    }
    h1 {
      font-size: 1.3rem;
      color: var(--accent);
      margin-bottom: 24px;
      white-space: normal;
    }
    h2, h3 {
      font-size: 1.1rem;
      color: #181818;
      margin: 8px 0 0;
      padding-bottom: 3px;
      border-bottom: 1px solid var(--border);
      white-space: normal;
    }
    .article img { max-width: 100%; border-radius: 8px; margin: 12px 0; }
    .article iframe { max-width: 100%; margin: 16px 0; }
    .nav {
      max-width: 820px;
      margin: 24px auto 0;
      display: flex;
      justify-content: space-between;
      font-size: 0.9rem;
    }
    .nav a { color: var(--accent); text-decoration: none; }