/* ============================================================
   AI実装顧問 — shared design system
   White × ink × deep indigo(#3E1487). Mincho display × gothic body.
   ============================================================ */
:root{
  --pp:#3E1487;        /* primary deep indigo */
  --pp2:#5B3799;       /* secondary purple */
  --tint:#F0ECF5;      /* lavender tint */
  --soft:#FAF9FC;      /* near-white section bg */
  --ink:#15131c;       /* body text */
  --mut:#56525f;       /* muted text */
  --line:rgba(20,16,32,.10);
  --line-soft:rgba(20,16,32,.055);
  --bg:#ffffff;
  --maxw:1080px;
  --serif:'Noto Serif JP',serif;
  --sans:'Noto Sans JP',system-ui,sans-serif;
  --mono:'Roboto Mono',ui-monospace,Menlo,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font-family:var(--sans);font-weight:400;line-height:1.95;
  font-size:16px;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4{font-family:var(--serif);font-weight:600;line-height:1.42;margin:0;letter-spacing:.01em}
strong,b{font-weight:700}
.pp{color:var(--pp)}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 28px}

/* ---- eyebrow / label (mono, encodes section identity) ---- */
.eyebrow{
  font-family:var(--mono);font-size:11px;font-weight:500;letter-spacing:.22em;
  text-transform:uppercase;color:var(--pp);display:flex;align-items:center;gap:11px;margin:0 0 18px;
}
.eyebrow::before{content:"";width:26px;height:1.5px;background:var(--pp);display:inline-block}
.eyebrow .jp{font-family:var(--sans);letter-spacing:.08em;color:var(--mut);text-transform:none;font-size:11.5px}

/* ---- header / nav ---- */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.78);
  backdrop-filter:saturate(180%) blur(12px);-webkit-backdrop-filter:saturate(180%) blur(12px);
  border-bottom:1px solid var(--line-soft);transition:box-shadow .3s}
.site-header.scrolled{box-shadow:0 1px 24px rgba(20,16,32,.06)}
.nav{display:flex;align-items:center;justify-content:space-between;max-width:var(--maxw);margin:0 auto;padding:15px 28px}
.brand{font-family:var(--serif);font-weight:600;font-size:19px;letter-spacing:.04em;color:var(--ink)}
.brand .dot{color:var(--pp)}
.nav-links{display:flex;align-items:center;gap:30px}
.nav-links a{font-size:14px;color:var(--mut);font-weight:500;letter-spacing:.02em;transition:color .2s;position:relative}
.nav-links a:hover{color:var(--pp)}
.nav-links a.active{color:var(--ink)}
.nav-cta{display:inline-flex;align-items:center;gap:7px;background:var(--pp);color:#fff;font-size:14px;
  font-weight:500;padding:10px 20px;border-radius:8px;transition:transform .2s,box-shadow .2s,background .2s}
.nav-cta:hover{background:#33106f;transform:translateY(-1px);box-shadow:0 8px 22px rgba(62,20,135,.26)}
/* override .nav-links a color (higher specificity) so CTA text stays white */
.nav-links a.nav-cta,.nav-links a.nav-cta:hover{color:#fff}
.nav-toggle{display:none;background:none;border:0;cursor:pointer;padding:6px;color:var(--ink)}

/* ---- buttons ---- */
.btn{display:inline-flex;align-items:center;gap:9px;font-family:var(--sans);font-weight:500;
  font-size:15px;padding:14px 28px;border-radius:9px;cursor:pointer;border:1px solid transparent;
  transition:transform .2s,box-shadow .2s,background .2s,border-color .2s;text-decoration:none}
.btn-primary{background:var(--pp);color:#fff}
.btn-primary:hover{background:#33106f;transform:translateY(-2px);box-shadow:0 12px 30px rgba(62,20,135,.28)}
.btn-ghost{background:transparent;color:var(--pp);border-color:var(--line)}
.btn-ghost:hover{border-color:var(--pp);background:var(--tint)}
.btn .arrow{transition:transform .25s}
.btn:hover .arrow{transform:translateX(4px)}

/* ---- sections ---- */
.section{padding:108px 0;position:relative}
.section.soft{background:var(--soft)}
.section.tint{background:var(--tint)}
.section-head{max-width:680px;margin:0 0 52px}
.section-head h2{font-size:clamp(26px,3.4vw,38px);margin-bottom:18px}
.section-head p{color:var(--mut);font-size:16px;margin:0}
.lead{font-size:17px;line-height:2;color:var(--mut)}

/* ---- reveal on scroll ---- */
.reveal{opacity:0;transform:translateY(22px);transition:opacity .8s cubic-bezier(.2,.7,.2,1),transform .8s cubic-bezier(.2,.7,.2,1)}
.reveal.in{opacity:1;transform:none}

/* ---- footer ---- */
.site-footer{background:#0f0d16;color:#cfc9da;padding:64px 0 40px}
.foot-top{display:flex;justify-content:space-between;gap:40px;flex-wrap:wrap;align-items:flex-start}
.foot-brand{font-family:var(--serif);font-size:22px;color:#fff;letter-spacing:.04em}
.foot-brand .dot{color:var(--pp2)}
.foot-tag{font-size:13.5px;color:#8d869c;margin-top:12px;max-width:30em;line-height:1.85}
.foot-nav{display:flex;gap:48px;flex-wrap:wrap}
.foot-col h4{font-family:var(--mono);font-size:10.5px;letter-spacing:.18em;text-transform:uppercase;color:#7c7590;font-weight:500;margin:0 0 16px}
.foot-col a{display:block;font-size:14px;color:#cfc9da;margin-bottom:11px;transition:color .2s}
.foot-col a:hover{color:#fff}
.foot-bottom{margin-top:48px;padding-top:24px;border-top:1px solid rgba(255,255,255,.1);
  display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;font-size:12px;color:#79728c}

/* ---- responsive ---- */
@media(max-width:760px){
  .section{padding:72px 0}
  .nav-links{position:fixed;inset:62px 0 auto 0;background:#fff;flex-direction:column;gap:0;
    border-bottom:1px solid var(--line);padding:8px 0;transform:translateY(-12px);opacity:0;
    pointer-events:none;transition:.25s;box-shadow:0 20px 40px rgba(20,16,32,.1)}
  .nav-links.open{transform:none;opacity:1;pointer-events:auto}
  .nav-links a{padding:14px 28px;width:100%;font-size:15px}
  .nav-links .nav-cta{margin:8px 28px;width:calc(100% - 56px);justify-content:center}
  .nav-toggle{display:block}
}
@media(prefers-reduced-motion:reduce){
  *{scroll-behavior:auto!important}
  .reveal{transition:none;opacity:1;transform:none}
  .btn,.nav-cta{transition:none}
}
:focus-visible{outline:2.5px solid var(--pp);outline-offset:3px;border-radius:3px}

/* ---- inner page hero ---- */
.page-hero{padding:118px 0 56px;background:radial-gradient(110% 80% at 78% 0%,#faf9ff,#fff 60%);border-bottom:1px solid var(--line-soft)}
.page-hero h1{font-size:clamp(30px,4.6vw,52px);line-height:1.34;margin:14px 0 20px}
.page-hero .lead{max-width:34em}
.crumb{font-family:var(--mono);font-size:11px;letter-spacing:.12em;text-transform:uppercase;color:var(--mut)}
.crumb a{color:var(--pp)}
@media(max-width:760px){.page-hero{padding:92px 0 44px}}