:root {
  --bg: #f4f7fb;
  --surface: #ffffff;
  --surface-2: #f0f5fb;
  --text: #17212b;
  --muted: #5b6b7c;
  --line: #e1e8f0;
  --brand: #1E6FD9;
  --brand-2: #29B5E8;
  --accent: #0ea5e9;
  --ga: #0f9d58;
  --ga-bg: #e6f6ee;
  --preview: #1E6FD9;
  --preview-bg: #e8f0fd;
  --client: #6b7280;
  --client-bg: #eef0f3;
  --jp: #d9432b;
  --jp-bg: #fdecea;
  --ok: #0f9d58;
  --ng: #d9432b;
  --shadow: 0 1px 2px rgba(16, 33, 56, .05), 0 8px 24px rgba(16, 33, 56, .06);
  --radius: 16px;
  color-scheme: light;
}
/* ダークテーマ: OS設定に従う（明示的に「明るい」を選んだ場合を除く） */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0d1520;
    --surface: #151f2d;
    --surface-2: #1b2736;
    --text: #e8eef5;
    --muted: #9fb0c2;
    --line: #26344a;
    --ga-bg: #113526;
    --preview-bg: #142a4a;
    --client-bg: #26303c;
    --jp-bg: #3d1e1a;
    --shadow: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px rgba(0,0,0,.35);
    color-scheme: dark;
  }
}
/* ダークテーマ: 表示設定で「暗い」を選んだ場合 */
:root[data-theme="dark"] {
  --bg: #0d1520;
  --surface: #151f2d;
  --surface-2: #1b2736;
  --text: #e8eef5;
  --muted: #9fb0c2;
  --line: #26344a;
  --ga-bg: #113526;
  --preview-bg: #142a4a;
  --client-bg: #26303c;
  --jp-bg: #3d1e1a;
  --shadow: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px rgba(0,0,0,.35);
  color-scheme: dark;
}
/* 文字の大きさ（表示設定） */
:root[data-size="large"] { font-size: 112.5%; }
:root[data-size="xlarge"] { font-size: 125%; }
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Inter", "Noto Sans JP", system-ui, -apple-system, "Segoe UI", "Hiragino Sans", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  color: var(--text);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(41,181,232,.18), transparent 60%),
    radial-gradient(900px 400px at 95% 0%, rgba(30,111,217,.14), transparent 60%),
    var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }
code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: .92em; background: var(--surface-2); padding: .1em .4em; border-radius: 6px; overflow-wrap: anywhere; }
.card { overflow-wrap: anywhere; }
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 20px; }
.skip { position: absolute; left: -999px; top: 0; }
.skip:focus { left: 12px; top: 12px; background: var(--surface); padding: 8px 12px; z-index: 99; }

/* header */
.site-header {
  position: sticky; top: 0; z-index: 20;
  backdrop-filter: saturate(160%) blur(12px);
  background: color-mix(in srgb, var(--surface) 82%, transparent);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 68px; padding: 8px 0; }
.nav { margin-left: auto; }
.brand { display: flex; align-items: center; gap: 12px; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand img { border-radius: 10px; box-shadow: var(--shadow); }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-title { font-weight: 800; font-size: 1.15rem; letter-spacing: .01em; }
.brand-sub { font-size: .72rem; color: var(--muted); }
.nav { display: flex; gap: 4px; }
.nav a { padding: 8px 12px; border-radius: 999px; font-size: .9rem; font-weight: 600; color: var(--muted); }
.nav a:hover { background: var(--surface-2); color: var(--text); text-decoration: none; }

/* hero */
.hero { padding: 40px 20px 8px; }
.hero-inner { max-width: 820px; }
.eyebrow { margin: 0 0 6px; font-size: .8rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--brand); }
.hero h1 { margin: 0; font-size: clamp(1.6rem, 3.4vw, 2.4rem); line-height: 1.3; font-weight: 900; letter-spacing: -.01em; }
.lead { margin: 12px 0 0; font-size: 1.02rem; color: var(--muted); }
.meta { margin: 10px 0 0; font-size: .85rem; color: var(--muted); }

/* layout */
.layout { display: grid; grid-template-columns: minmax(0, 1fr) 340px; gap: 24px; padding-top: 24px; padding-bottom: 48px; align-items: start; }
.col-main, .col-side { display: flex; flex-direction: column; gap: 24px; min-width: 0; }
/* サブ列はメイン列と一緒にスクロールする（固定しない） */
.col-side { position: static; }
@media (max-width: 960px) {
  .layout { grid-template-columns: 1fr; }
  .nav { display: none; }
}

/* cards */
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
}
@media (max-width: 600px) { .card { padding: 20px; } }
.section-head { display: flex; align-items: baseline; justify-content: space-between; flex-wrap: wrap; gap: 8px; margin-bottom: 6px; }
.section-head h2 { margin: 0; font-size: 1.35rem; font-weight: 800; display: flex; align-items: center; gap: 8px; }
.ico { font-size: 1.1em; }
.section-note { margin: 0; font-size: .82rem; color: var(--muted); }
.section-desc { margin: 4px 0 14px; color: var(--muted); font-size: .95rem; }
.sub-h { font-size: 1.05rem; margin: 26px 0 10px; font-weight: 700; }
.fineprint { font-size: .8rem; color: var(--muted); margin-top: 12px; }

/* badges */
.badge { display: inline-flex; align-items: center; font-size: .72rem; font-weight: 700; padding: 2px 9px; border-radius: 999px; letter-spacing: .02em; white-space: nowrap; }
.badge-ga { color: var(--ga); background: var(--ga-bg); }
.badge-preview { color: var(--preview); background: var(--preview-bg); }
.badge-client { color: var(--client); background: var(--client-bg); }
.badge-jp { color: var(--jp); background: var(--jp-bg); }
.badge-note { color: var(--muted); background: var(--surface-2); }
.legend { display: flex; flex-wrap: wrap; align-items: center; gap: 4px 6px; font-size: .78rem; color: var(--muted); margin-bottom: 14px; }
.legend > span:not(.badge) { margin-right: 10px; }

/* updates */
.day-group { border-top: 1px solid var(--line); padding: 14px 0 6px; }
.day-group:first-child { border-top: 0; }
.day-label { font-weight: 800; font-size: .95rem; margin: 0 0 8px; display: flex; align-items: center; gap: 8px; }
.day-label .dow { font-size: .75rem; color: var(--muted); font-weight: 600; }
.update { display: grid; grid-template-columns: auto 1fr; gap: 10px 12px; padding: 10px 12px; border-radius: 12px; margin-bottom: 6px; }
.update:hover { background: var(--surface-2); }
.update .badges { display: flex; flex-direction: column; gap: 4px; padding-top: 3px; }
.update h4 { margin: 0; font-size: 1rem; font-weight: 700; }
.update p { margin: 4px 0 0; font-size: .92rem; color: var(--muted); }
.update .area { font-size: .75rem; font-weight: 600; color: var(--brand); margin-right: 6px; }
.update .link { font-size: .82rem; }
.recap { margin-top: 14px; border-top: 1px solid var(--line); padding-top: 12px; }
.recap summary { cursor: pointer; font-weight: 700; font-size: .95rem; color: var(--muted); }
.recap ul { margin: 10px 0 0; padding-left: 20px; font-size: .9rem; color: var(--muted); }
.recap li { margin-bottom: 4px; }
.bcr { margin-top: 16px; padding: 14px 16px; border-radius: 12px; background: var(--surface-2); font-size: .9rem; }
.bcr h4 { margin: 0 0 6px; font-size: .95rem; }
.bcr p { margin: 0; color: var(--muted); }
.bcr ul { margin: 6px 0 0; padding-left: 20px; color: var(--muted); }

/* column */
.column-article h3 { font-size: 1.45rem; line-height: 1.4; margin: 6px 0 8px; font-weight: 900; }
.column-lead { font-size: 1rem; color: var(--muted); border-left: 4px solid var(--brand-2); padding-left: 12px; margin: 0 0 18px; }
.column-article h4 { font-size: 1.08rem; margin: 26px 0 8px; padding-bottom: 6px; border-bottom: 2px solid var(--line); }
.column-article p { margin: 0 0 12px; font-size: .98rem; }
.column-article ul { margin: 0 0 12px; padding-left: 22px; font-size: .96rem; }
.column-article li { margin-bottom: 4px; }
.callout { background: var(--surface-2); border-radius: 12px; padding: 12px 16px; margin: 12px 0 16px; font-size: .94rem; }
.callout strong { color: var(--brand); }
.sources { margin-top: 20px; padding-top: 12px; border-top: 1px dashed var(--line); font-size: .82rem; color: var(--muted); }
.sources ul { margin: 6px 0 0; padding-left: 18px; }
.sources li { margin-bottom: 2px; word-break: break-all; }

/* certs */
.cert-news { display: grid; gap: 10px; }
.cert-news-item { padding: 12px 14px; border-radius: 12px; border: 1px solid var(--line); }
.cert-news-item .date { font-size: .78rem; color: var(--muted); font-weight: 600; }
.cert-news-item h4 { margin: 2px 0 4px; font-size: 1rem; }
.cert-news-item p { margin: 0; font-size: .92rem; color: var(--muted); }
.empty-note { padding: 14px 16px; border-radius: 12px; background: var(--surface-2); font-size: .93rem; }
.table-scroll { overflow-x: auto; }
.cert-table { width: 100%; border-collapse: collapse; font-size: .9rem; min-width: 560px; }
.cert-table th, .cert-table td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
.cert-table th { font-size: .78rem; color: var(--muted); font-weight: 700; letter-spacing: .04em; }
.cert-table .tier { font-weight: 700; white-space: nowrap; }
.cert-table code { white-space: nowrap; }

/* quiz */
.q { border: 1px solid var(--line); border-radius: 14px; padding: 18px; margin-bottom: 14px; }
.q-head { display: flex; align-items: center; gap: 8px; margin-bottom: 6px; flex-wrap: wrap; }
.q-num { font-weight: 900; color: var(--brand); }
.q-cat { font-size: .74rem; font-weight: 700; color: var(--muted); background: var(--surface-2); padding: 2px 8px; border-radius: 999px; }
.q-text { margin: 0 0 12px; font-weight: 600; font-size: 1rem; }
.choices { display: grid; gap: 8px; }
.choice {
  text-align: left; width: 100%; font: inherit; font-size: .95rem; color: var(--text);
  background: var(--surface-2); border: 1px solid var(--line); border-radius: 10px;
  padding: 10px 12px; cursor: pointer; display: flex; gap: 10px; align-items: flex-start;
}
.choice:hover:not(:disabled) { border-color: var(--brand); }
.choice:disabled { cursor: default; opacity: .9; }
.choice .key { font-weight: 800; color: var(--brand); min-width: 1.4em; }
.choice.correct { border-color: var(--ok); background: var(--ga-bg); }
.choice.wrong { border-color: var(--ng); background: var(--jp-bg); }
.verdict { margin: 12px 0 6px; font-weight: 800; }
.verdict.ok { color: var(--ok); }
.verdict.ng { color: var(--ng); }
.explain { background: var(--surface-2); border-radius: 12px; padding: 14px 16px; font-size: .93rem; }
.explain p { margin: 0 0 8px; }
.explain p:last-child { margin-bottom: 0; }
.explain ul { margin: 4px 0 8px; padding-left: 20px; }
.quiz-result { margin-top: 8px; padding: 14px 16px; border-radius: 12px; background: var(--preview-bg); font-weight: 700; }

/* sidebar */
.side-card { padding: 22px; }
.side-h { margin: 0 0 12px; font-size: .8rem; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; color: var(--brand); }
.profile { display: flex; gap: 12px; align-items: flex-start; }
.avatar { width: 52px; height: 52px; border-radius: 50%; flex: none; box-shadow: 0 0 0 2px var(--surface), 0 0 0 4px var(--brand-2); }
.profile-name { margin: 0; font-weight: 800; }
.profile-text { margin: 4px 0 0; font-size: .88rem; color: var(--muted); }
.side-column-no { margin: 0; font-size: .76rem; font-weight: 700; color: var(--muted); }
.side-column-title { margin: 4px 0 6px; font-weight: 800; line-height: 1.45; }
.side-column-lead { margin: 0 0 12px; font-size: .88rem; color: var(--muted); }
.btn { display: inline-block; padding: 8px 14px; border-radius: 999px; background: var(--brand); color: #fff; font-size: .85rem; font-weight: 700; }
.btn:hover { text-decoration: none; filter: brightness(1.08); }
.related-list, .archive-list { list-style: none; margin: 0; padding: 0; font-size: .9rem; }
.related-list li, .archive-list li { padding: 6px 0; border-top: 1px solid var(--line); }
.related-list li:first-child, .archive-list li:first-child { border-top: 0; padding-top: 0; }
.archive-list .cur { font-weight: 700; }
.archive-list .d { font-size: .78rem; color: var(--muted); margin-right: 6px; }
.related-empty { color: var(--muted); font-size: .88rem; }

/* footer */
.site-footer { border-top: 1px solid var(--line); padding: 24px 0 40px; font-size: .8rem; color: var(--muted); }
.site-footer p { margin: 0 0 6px; }
.error { padding: 16px; border-radius: 12px; background: var(--jp-bg); color: var(--jp); }

/* clients */
.clients { margin-top: 18px; border-top: 1px solid var(--line); padding-top: 6px; }
.clients .section-head { margin-bottom: 4px; }
.clients-h { margin: 12px 0 8px; }
.client-table { width: 100%; border-collapse: collapse; font-size: .9rem; min-width: 560px; }
.client-table th, .client-table td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
.client-table th { font-size: .78rem; color: var(--muted); font-weight: 700; letter-spacing: .04em; }
.client-table .name { font-weight: 700; }
.client-table .new td:first-child::before { content: "NEW"; display: inline-block; font-size: .62rem; font-weight: 800; color: var(--ga); background: var(--ga-bg); padding: 1px 6px; border-radius: 999px; margin-right: 6px; vertical-align: middle; }
.client-table .pre { color: var(--muted); font-size: .8rem; }

/* events */
.event { display: grid; grid-template-columns: 84px 1fr; gap: 14px; padding: 14px 0; border-top: 1px solid var(--line); }
.event:first-child { border-top: 0; padding-top: 4px; }
.event-date { text-align: center; background: var(--surface-2); border-radius: 12px; padding: 8px 4px; align-self: start; }
.event-date .m { display: block; font-size: .7rem; font-weight: 700; color: var(--muted); letter-spacing: .06em; }
.event-date .d { display: block; font-size: 1.35rem; font-weight: 900; line-height: 1.1; color: var(--brand); }
.event-date .r { display: block; font-size: .7rem; color: var(--muted); }
.event h4 { margin: 0; font-size: 1rem; }
.event .kind { font-size: .72rem; font-weight: 700; padding: 2px 8px; border-radius: 999px; background: var(--preview-bg); color: var(--preview); margin-right: 6px; vertical-align: middle; }
.event .kind.community { background: var(--ga-bg); color: var(--ga); }
.event .kind.online { background: var(--client-bg); color: var(--client); }
.event p { margin: 4px 0 0; font-size: .92rem; color: var(--muted); }
.event .place { font-size: .82rem; color: var(--muted); }
.event .link { font-size: .84rem; }
.event-sources { margin-top: 12px; padding: 12px 14px; border-radius: 12px; background: var(--surface-2); font-size: .85rem; color: var(--muted); }
.event-sources ul { margin: 6px 0 0; padding-left: 18px; }

/* tips */
.tips { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
@media (max-width: 720px) { .tips { grid-template-columns: 1fr; } }
.tip { min-width: 0; border: 1px solid var(--line); border-radius: 14px; padding: 16px 18px; background: linear-gradient(180deg, var(--surface-2), transparent 60%); }
.tip .tip-kind { font-size: .72rem; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; color: var(--brand); }
.tip h4 { margin: 4px 0 8px; font-size: 1.02rem; line-height: 1.45; }
.tip p { margin: 0 0 8px; font-size: .92rem; }
.tip pre { margin: 8px 0; padding: 10px 12px; background: var(--text); color: var(--bg); border-radius: 10px; font-size: .8rem; line-height: 1.5; overflow-x: auto; }
.tip pre code { background: transparent; color: inherit; padding: 0; overflow-wrap: normal; }
.tip .takeaway { font-size: .88rem; color: var(--muted); border-top: 1px dashed var(--line); padding-top: 8px; margin-top: 6px; }
.client-table td:nth-child(2), .client-table td:nth-child(3) { white-space: nowrap; overflow-wrap: normal; }
.client-table .name { overflow-wrap: normal; }
.client-table td:nth-child(2) code { overflow-wrap: normal; }
.client-table td:nth-child(4) { min-width: 220px; }

/* brand + AI notice */
.brand-owner { font-size: .8rem; font-weight: 700; color: var(--muted); display: block; line-height: 1.1; }
.brand-fan { color: var(--brand); }
.ai-notice { margin-top: 14px; padding: 10px 12px; border-radius: 12px; background: var(--surface-2); font-size: .8rem; color: var(--muted); }
.ai-notice p { margin: 0; }

/* 表示設定ポップオーバー */
.prefs { position: relative; flex: none; }
.prefs summary { list-style: none; cursor: pointer; display: inline-flex; align-items: center; gap: 6px; padding: 7px 12px; border-radius: 999px; border: 1px solid var(--line); background: var(--surface); font-size: .82rem; font-weight: 700; color: var(--muted); user-select: none; }
.prefs summary::-webkit-details-marker { display: none; }
.prefs summary:hover, .prefs[open] summary { color: var(--text); border-color: var(--brand); }
.prefs summary:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; }
.prefs-ico { font-weight: 800; letter-spacing: -.02em; font-family: "Inter", sans-serif; }
.prefs-panel { position: absolute; right: 0; top: calc(100% + 8px); width: 290px; max-width: calc(100vw - 32px); background: var(--surface); border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow); padding: 14px; z-index: 30; }
.pref-row + .pref-row { margin-top: 12px; }
.pref-label { font-size: .7rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: 6px; }
.seg { display: grid; grid-auto-flow: column; grid-auto-columns: 1fr; gap: 4px; background: var(--surface-2); padding: 4px; border-radius: 10px; }
.seg button { font: inherit; font-size: .85rem; font-weight: 600; padding: 7px 4px; border: 0; border-radius: 8px; background: transparent; color: var(--muted); cursor: pointer; white-space: nowrap; }
.seg button:hover { color: var(--text); }
.seg button[aria-pressed="true"] { background: var(--surface); color: var(--text); box-shadow: 0 1px 2px rgba(16,33,56,.12); }
.seg button:focus-visible { outline: 2px solid var(--brand); outline-offset: 1px; }
.pref-note { margin: 12px 0 0; font-size: .74rem; color: var(--muted); }
@media (max-width: 600px) { .prefs-text { display: none; } .prefs summary { padding: 7px 10px; } }