/* ============================================================
   MUKIAI Blog — note的リーディングUI × ブランド
   読み心地（可読性）とSEO見出し階層を最優先に設計
   ============================================================ */
:root{
  --navy:#0f2742; --navy-2:#13315c; --navy-deep:#091b30;
  --teal:#1f6f78; --teal-2:#2b8a94; --teal-soft:#e3f0f1;
  --gold:#c8a24a; --gold-soft:#f1e6c9;
  --ink:#1a2b3c; --muted:#5a6b7b; --line:#e6e0d4;
  --bg:#faf8f3; --card:#ffffff;
  --shadow:0 18px 40px -18px rgba(15,39,66,.16);
  --shadow-lg:0 30px 70px -24px rgba(15,39,66,.28);
  --ease:cubic-bezier(.22,.61,.36,1);
  --read:720px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:"Noto Sans JP",system-ui,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.85;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
}
.serif{font-family:"Noto Serif JP",serif}
a{color:var(--teal);text-decoration:none}
img{max-width:100%;display:block}
.wrap{max-width:1140px;margin:0 auto;padding:0 24px}

/* ===== 読書進捗バー ===== */
.progress{position:fixed;top:0;left:0;height:3px;width:0;z-index:80;
  background:linear-gradient(90deg,var(--teal),var(--gold));transition:width .1s linear}

/* ===== ヘッダー ===== */
.site-header{position:sticky;top:0;z-index:60;background:rgba(250,248,243,.9);
  backdrop-filter:blur(14px);border-bottom:1px solid rgba(15,39,66,.07)}
.site-header .nav{display:flex;align-items:center;justify-content:space-between;height:66px}
.brand-logo{height:30px;width:auto}
.menu{display:flex;align-items:center;gap:24px}
.menu .link{font-size:14px;font-weight:700;color:var(--navy);position:relative;white-space:nowrap}
.menu .link:hover{color:var(--teal)}
.menu .link-cc{color:var(--teal)}
.menu .link.current{color:var(--teal)}
.btn{display:inline-flex;align-items:center;gap:8px;border-radius:999px;font-weight:700;
  font-size:14px;padding:11px 20px;text-decoration:none;border:none;cursor:pointer;transition:.25s var(--ease)}
.btn-line{background:linear-gradient(120deg,#06c755,#04a847);color:#fff;
  box-shadow:0 8px 22px -8px rgba(6,199,85,.6);animation:lineGlow 2.6s ease-in-out infinite}
.btn-line:hover{transform:translateY(-2px);box-shadow:0 14px 30px -8px rgba(6,199,85,.7)}
.linelogo{height:18px;width:18px;filter:brightness(0) invert(1)}
@keyframes lineGlow{0%,100%{box-shadow:0 8px 22px -8px rgba(6,199,85,.55)}
  50%{box-shadow:0 8px 30px -4px rgba(6,199,85,.85)}}
.burger{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:6px}
.burger span{width:24px;height:2px;background:var(--navy);border-radius:2px;transition:.3s}
.mobile-menu{display:none;position:fixed;inset:0 0 auto 0;z-index:59;background:var(--bg);
  box-shadow:var(--shadow-lg);padding:84px 24px 30px;transform:translateY(-110%);transition:transform .4s var(--ease)}
.mobile-menu.open{transform:none}
.mobile-menu a{display:block;padding:15px 4px;font-size:17px;font-weight:700;color:var(--navy);border-bottom:1px solid var(--line)}
.mobile-menu .btn-line{margin-top:20px;width:100%;justify-content:center;color:#fff}
@media(max-width:920px){.menu{display:none}.burger{display:flex}.mobile-menu{display:block}}

/* ===== パンくず ===== */
.crumb{font-size:12.5px;color:var(--muted);padding:18px 0 0}
.crumb a{color:var(--muted)}.crumb a:hover{color:var(--teal)}
.crumb span{margin:0 7px;opacity:.6}

/* ============================================================
   記事ページ
   ============================================================ */
.article{padding:10px 0 60px}
.article-grid{display:grid;grid-template-columns:minmax(0,1fr) 296px;gap:54px;align-items:start}
.article-main{min-width:0;max-width:var(--read);justify-self:center;width:100%}

/* 記事ヘッダー */
.a-head{margin:14px 0 26px}
.chip{display:inline-block;background:var(--teal-soft);color:var(--teal);font-size:12px;
  font-weight:700;padding:5px 13px;border-radius:999px;letter-spacing:.02em}
.a-title{font-family:"Noto Serif JP",serif;font-weight:900;color:var(--navy);
  font-size:clamp(26px,3.4vw,40px);line-height:1.42;margin:16px 0 14px;letter-spacing:.01em}
.a-meta{display:flex;flex-wrap:wrap;align-items:center;gap:14px;font-size:13px;color:var(--muted)}
.a-meta .who{display:flex;align-items:center;gap:8px;font-weight:700;color:var(--navy)}
.a-meta .who img{height:26px;width:26px;border-radius:50%;object-fit:cover}
.a-meta .dot{width:3px;height:3px;border-radius:50%;background:var(--line)}
.a-cover{margin:24px 0 6px;border-radius:16px;overflow:hidden;box-shadow:var(--shadow);aspect-ratio:16/9;background:linear-gradient(135deg,var(--navy),var(--teal))}
.a-cover img{width:100%;height:100%;object-fit:cover}

/* 目次（モバイル：本文上のカード） */
.toc-inline{background:var(--card);border:1px solid var(--line);border-radius:14px;
  padding:18px 20px;margin:24px 0 30px}
.toc-inline .toc-ttl{font-size:13px;font-weight:900;color:var(--navy);letter-spacing:.06em;
  margin-bottom:10px;display:flex;align-items:center;gap:8px}
.toc-inline .toc-ttl::before{content:"";width:14px;height:2px;background:var(--gold)}
.toc-list{list-style:none}
.toc-list a{display:block;color:var(--muted);font-size:13.5px;padding:5px 0;line-height:1.6;border-left:2px solid transparent;padding-left:12px;margin-left:-12px;transition:.2s}
.toc-list a:hover{color:var(--teal)}
.toc-list .lv3 a{padding-left:26px;font-size:13px;opacity:.92}
.toc-list a.active{color:var(--teal);border-left-color:var(--teal);font-weight:700}

/* ===== 本文プロース（note的） ===== */
.prose{font-size:17px;line-height:1.98;color:#243441;word-break:break-word}
.prose>*+*{margin-top:1.5em}
.prose h2{font-family:"Noto Serif JP",serif;font-weight:800;color:var(--navy);
  font-size:clamp(21px,2.5vw,27px);line-height:1.5;margin:2.2em 0 .2em;padding-bottom:.5em;
  border-bottom:2px solid var(--line);scroll-margin-top:84px;position:relative}
.prose h2::after{content:"";position:absolute;left:0;bottom:-2px;width:56px;height:2px;background:var(--gold)}
.prose h3{font-weight:800;color:var(--navy);font-size:clamp(18px,2vw,21px);line-height:1.55;
  margin:1.9em 0 .1em;padding-left:14px;border-left:4px solid var(--teal);scroll-margin-top:84px}
.prose h4{font-weight:800;color:var(--teal);font-size:16.5px;margin:1.6em 0 .1em;scroll-margin-top:84px}
.prose p{margin-top:1.25em}
.prose a{color:var(--teal);text-decoration:underline;text-underline-offset:3px;text-decoration-thickness:1px;font-weight:500}
.prose a:hover{color:var(--teal-2)}
.prose strong{font-weight:800;color:var(--navy);background:linear-gradient(transparent 62%,var(--gold-soft) 62%);padding:0 1px}
.prose em{font-style:normal;color:var(--teal);font-weight:700}
.prose u{text-decoration:none;border-bottom:2.5px solid var(--teal-2);padding-bottom:1px;font-weight:600}
.prose .point{display:block;background:#fff;border:1px solid var(--line);border-left:4px solid var(--gold);
  border-radius:0 12px 12px 0;padding:14px 18px;font-size:15.5px;box-shadow:0 8px 22px -16px rgba(15,39,66,.25)}
.prose ul,.prose ol{padding-left:1.4em;margin-top:1.2em}
.prose li{margin:.5em 0;padding-left:.2em}
.prose ul>li::marker{color:var(--teal)}
.prose ol>li::marker{color:var(--teal);font-weight:700}
.prose blockquote{border-left:4px solid var(--teal);background:var(--teal-soft);
  border-radius:0 12px 12px 0;padding:16px 20px;color:#2b4350;font-size:16px}
.prose blockquote p{margin:0}
.prose img{border-radius:12px;box-shadow:var(--shadow);margin:1.6em auto}
.prose figure{margin:1.8em 0}
.prose figcaption{text-align:center;font-size:12.5px;color:var(--muted);margin-top:8px}
.prose hr{border:none;height:1px;background:var(--line);margin:2.4em 0}
.prose code{font-family:"JetBrains Mono",ui-monospace,monospace;font-size:.88em;
  background:#eef2f4;color:var(--navy);padding:2px 6px;border-radius:6px}
.prose pre{background:var(--navy-deep);color:#e7eef5;border-radius:12px;padding:18px 20px;overflow-x:auto;font-size:14px;line-height:1.7}
.prose pre code{background:none;color:inherit;padding:0}
.prose table{width:100%;border-collapse:collapse;font-size:15px;margin-top:1.2em;overflow:hidden;border-radius:10px}
.prose th,.prose td{border:1px solid var(--line);padding:11px 14px;text-align:left}
.prose th{background:var(--navy);color:#fff;font-weight:700}
.prose tr:nth-child(even) td{background:#fbfaf6}

/* ===== 記事内CTA（中間） ===== */
.cta-mid{background:linear-gradient(135deg,var(--navy),var(--navy-2));color:#fff;border-radius:18px;
  padding:28px 30px;margin:2.6em 0;box-shadow:var(--shadow)}
.cta-mid h4{font-family:"Noto Serif JP",serif;font-size:19px;font-weight:800;color:#fff;margin-bottom:8px}
.cta-mid p{font-size:14px;color:rgba(255,255,255,.82);margin-bottom:16px}
.cta-mid .btn-line{color:#fff}
.cta-mid .sub-cta{display:block;margin-top:14px;color:rgba(255,255,255,.85);font-size:13px;
  text-decoration:underline;text-underline-offset:3px}
.cta-mid .sub-cta:hover{color:#fff}

/* ===== 記事末CTA（強）＋3択 ===== */
.a-cta{margin:48px 0 0}
.cta-line-box{background:linear-gradient(135deg,#06c755,#04a847);border-radius:22px;padding:34px 30px;
  text-align:center;color:#fff;box-shadow:0 24px 50px -20px rgba(6,199,85,.6)}
.cta-line-box .lead{font-family:"Noto Serif JP",serif;font-size:clamp(20px,2.6vw,26px);font-weight:800;line-height:1.5}
.cta-line-box p{font-size:14px;opacity:.92;margin:12px 0 22px}
.cta-line-box .btn{background:#fff;color:#04a847;font-size:16px;padding:15px 34px;box-shadow:0 10px 26px -8px rgba(0,0,0,.3);animation:none}
.cta-line-box .btn:hover{transform:translateY(-2px)}
.cta-line-box .btn .linelogo{filter:none}
.cta-line-box .cta-sub{display:block;margin-top:16px;color:rgba(255,255,255,.92);font-size:13.5px;
  text-decoration:underline;text-underline-offset:3px}
.cta-line-box .cta-sub:hover{color:#fff}
.cta-3{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:18px}
.cta-3 a{display:flex;flex-direction:column;gap:6px;background:var(--card);border:1px solid var(--line);
  border-radius:14px;padding:18px 18px;transition:.25s var(--ease)}
.cta-3 a:hover{transform:translateY(-3px);box-shadow:var(--shadow);border-color:var(--teal)}
.cta-3 .ic{display:inline-flex;width:34px;height:34px;align-items:center;justify-content:center;
  background:var(--teal-soft);color:var(--teal);border-radius:10px}
.cta-3 .ic svg{width:19px;height:19px}
.cta-3 a:hover .ic{background:var(--teal);color:#fff}
.cta-3 .t{font-weight:800;color:var(--navy);font-size:14.5px}
.cta-3 .d{font-size:12px;color:var(--muted);line-height:1.6}

/* ===== 執筆者ボックス ===== */
.author-box{display:flex;gap:16px;align-items:flex-start;background:var(--card);border:1px solid var(--line);
  border-radius:16px;padding:22px 24px;margin-top:30px}
.author-box img{height:56px;width:56px;border-radius:50%;object-fit:cover;flex:none}
.author-box .nm{font-weight:800;color:var(--navy);font-size:15px}
.author-box .bio{font-size:13px;color:var(--muted);margin-top:5px;line-height:1.75}
.author-box .bio a{color:var(--teal);font-weight:700}

/* ===== 関連記事 ===== */
.related{margin-top:54px}
.related h3{font-family:"Noto Serif JP",serif;font-size:20px;color:var(--navy);margin-bottom:18px}
.rel-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}

/* ===== 右サイドレール（PC固定） ===== */
.rail{position:sticky;top:88px;display:flex;flex-direction:column;gap:20px}
.rail .toc-card,.rail .line-card{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:20px}
.rail .toc-ttl{font-size:12px;font-weight:900;color:var(--navy);letter-spacing:.08em;margin-bottom:10px;display:flex;align-items:center;gap:8px}
.rail .toc-ttl::before{content:"";width:14px;height:2px;background:var(--gold)}
.rail .toc-list{max-height:60vh;overflow:auto}
.line-card{background:linear-gradient(135deg,var(--navy),var(--navy-2));border:none;color:#fff;text-align:center}
.line-card .t{font-weight:800;font-size:15px;margin-bottom:6px}
.line-card .d{font-size:12px;color:rgba(255,255,255,.78);margin-bottom:14px;line-height:1.7}
.line-card .btn-line{width:100%;justify-content:center;color:#fff}

/* ============================================================
   一覧ページ
   ============================================================ */
.blog-hero{padding:54px 0 30px;text-align:center}
.blog-hero .eyebrow{font-size:12px;font-weight:800;letter-spacing:.18em;color:var(--teal);text-transform:uppercase}
.blog-hero h1{font-family:"Noto Serif JP",serif;font-weight:900;color:var(--navy);font-size:clamp(28px,4vw,44px);margin:12px 0 10px}
.blog-hero p{color:var(--muted);font-size:15px;max-width:620px;margin:0 auto}
.post-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:26px;padding:24px 0 60px}
.post-card{display:flex;flex-direction:column;background:var(--card);border:1px solid var(--line);
  border-radius:18px;overflow:hidden;transition:.3s var(--ease);box-shadow:0 10px 30px -22px rgba(15,39,66,.3)}
.post-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);border-color:var(--teal-2)}
.post-thumb{aspect-ratio:16/9;overflow:hidden;background:linear-gradient(135deg,var(--navy),var(--teal));position:relative}
.post-thumb img{width:100%;height:100%;object-fit:cover;transition:.4s var(--ease)}
.post-card:hover .post-thumb img{transform:scale(1.05)}
.post-thumb .ph-cat{position:absolute;left:14px;bottom:14px;background:rgba(255,255,255,.92);color:var(--navy);font-size:11.5px;font-weight:800;padding:5px 12px;border-radius:999px}
.post-body{padding:18px 20px 22px;display:flex;flex-direction:column;flex:1}
.post-body .chip{margin-bottom:10px;align-self:flex-start}
.post-body h2{font-family:"Noto Serif JP",serif;font-size:18px;font-weight:800;color:var(--navy);line-height:1.5;margin-bottom:8px}
.post-body .ex{font-size:13px;color:var(--muted);line-height:1.8;flex:1}
.post-body .pm{display:flex;gap:10px;align-items:center;font-size:12px;color:var(--muted);margin-top:14px}
.blog-empty{text-align:center;color:var(--muted);padding:60px 0;font-size:15px}

/* ============================================================
   フッター
   ============================================================ */
footer{background:var(--navy-deep);color:rgba(255,255,255,.66);margin-top:40px}
footer .wrap{padding:46px 24px 26px}
.foot-top{display:flex;justify-content:space-between;gap:40px;flex-wrap:wrap;padding-bottom:30px;border-bottom:1px solid rgba(255,255,255,.1)}
.foot-brand{max-width:300px}
.foot-logo{height:30px;margin-bottom:14px}
.foot-brand p{font-size:12.5px;line-height:1.9}
.foot-nav{display:flex;gap:48px;flex-wrap:wrap}
.foot-nav h5{color:#fff;font-size:13px;margin-bottom:12px}
.foot-nav .col a{display:block;color:rgba(255,255,255,.66);font-size:12.5px;padding:4px 0}
.foot-nav .col a:hover{color:#fff}
.foot-bottom{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;padding-top:20px;font-size:12px}

/* ============================================================
   レスポンシブ
   ============================================================ */
@media(max-width:980px){
  .article-grid{grid-template-columns:1fr;gap:0}
  .rail{display:none}
  .post-grid,.rel-grid{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:680px){
  .post-grid,.rel-grid,.cta-3{grid-template-columns:1fr}
  .foot-top{flex-direction:column;gap:24px}
  .prose{font-size:16px}
}
@media(min-width:981px){.toc-inline{display:none}}

@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto!important}}