/* ============================================================
   site-chrome.css — 刷新4ページ専用 header/footer chrome
   出典: learn.html のインラインCSSから抽出（.site-header/.site-footer系）
   対象: privacy.html / terms.html / public_notice.html / 404.html のみ
   注意: 既存18ページはインライン<style>を使い続けるため本ファイルは参照しない
============================================================ */

:root{
  --blue:#3F66C0;
  --blue-deep:#123C86;
  --blue-deep-2:#0B2C66;
  --ink:#16233F;
  --sky-accent:#81BAEB;
  --line:#E4E9F2;

  --container:1120px;
  --gutter:clamp(20px,5vw,64px);
  --r-xs:8px;

  --font-en:'Montserrat', sans-serif;
  --ease:cubic-bezier(.16,.84,.44,1);
}

/* --- 土台リセット（下記chromeコンポーネントの前提） --- */
*,*::before,*::after{ box-sizing:border-box; }
a{ color:inherit; text-decoration:none; }
ul{ margin:0; padding:0; list-style:none; }
button{ font:inherit; color:inherit; background:none; border:none; cursor:pointer; }
svg{ display:block; }

/* sticky footer: コンテンツが短いページでもfooterが下端に貼り付くようにする */
body{ min-height:100vh; display:flex; flex-direction:column; }
main{ flex:1 0 auto; }

.container{ max-width:var(--container); margin-inline:auto; padding-inline:var(--gutter); }
.icon{ width:1em; height:1em; fill:none; stroke:currentColor; stroke-width:1.8; stroke-linecap:round; stroke-linejoin:round; }

/* ============================================================
   HEADER
============================================================ */
.site-header{ position:sticky; top:0; z-index:1000; background:rgba(255,255,255,.94); backdrop-filter:blur(14px); -webkit-backdrop-filter:blur(14px); border-bottom:1px solid var(--line); transition:box-shadow .3s var(--ease), padding .3s var(--ease); }
.site-header .container{ display:flex; align-items:center; justify-content:space-between; padding-block:26px; transition:padding .3s var(--ease); }
.site-header.is-scrolled{ box-shadow:0 10px 30px -20px rgba(18,60,134,.3); }
.site-header.is-scrolled .container{ padding-block:14px; }

.brand{ display:flex; align-items:center; gap:12px; }
.logo-badge{ width:40px; height:40px; flex-shrink:0; display:flex; align-items:center; justify-content:center; }
.logo-badge img{ width:40px; height:40px; display:block; }
.logo-word{ font-family:var(--font-en); font-weight:700; font-size:1.22rem; letter-spacing:.01em; white-space:nowrap; }
.logo-word .w-shift{ color:var(--blue); }

.nav-desktop{ display:flex; align-items:center; gap:clamp(22px,3vw,42px); }
.nav-desktop a{ font-weight:500; font-size:.95rem; position:relative; padding:6px 0; color:var(--ink); }
.nav-desktop a::after{ content:''; position:absolute; left:0; right:100%; bottom:0; height:2px; background:var(--blue); border-radius:2px; transition:right .3s var(--ease); }
.nav-desktop a:hover::after, .nav-desktop a:focus-visible::after, .nav-desktop a[aria-current="page"]::after{ right:0; }
.nav-desktop a[aria-current="page"]{ color:var(--blue-deep); }

.header-actions{ display:flex; align-items:center; gap:18px; }
.header-actions .btn{ border-radius:8px; }

.menu-toggle{ display:none; width:44px; height:44px; border-radius:var(--r-xs); align-items:center; justify-content:center; color:var(--ink); flex-shrink:0; }
.menu-toggle svg{ width:24px; height:24px; }
.menu-toggle .i-close{ display:none; }
.menu-toggle[aria-expanded="true"] .i-menu{ display:none; }
.menu-toggle[aria-expanded="true"] .i-close{ display:block; }

.mobile-nav{ display:grid; overflow:hidden; grid-template-rows:0fr; transition:grid-template-rows .35s var(--ease); background:#fff; border-bottom:1px solid var(--line); }
.mobile-nav.is-open{ grid-template-rows:1fr; }
.mobile-nav > div{ overflow:hidden; }
.mobile-nav-inner{ padding:8px var(--gutter) 28px; display:flex; flex-direction:column; gap:4px; }
.mobile-nav-inner a{ padding:14px 4px; font-weight:600; font-size:1.05rem; border-bottom:1px solid var(--line); }
.mobile-nav-inner a[aria-current="page"]{ color:var(--blue-deep); }
.mobile-nav-inner .btn{ margin-top:16px; justify-content:center; border-radius:8px; }

@media (min-width:861px){ .mobile-nav{ display:none; } }
@media (max-width:860px){
  .nav-desktop{ display:none; }
  .menu-toggle{ display:flex; }
}

/* ============================================================
   BUTTON / CIRCLE-ARROW（header・footer共通で使用）
============================================================ */
.circle-arrow{ width:38px; height:38px; border-radius:50%; flex-shrink:0; display:flex; align-items:center; justify-content:center; background:rgba(255,255,255,.22); color:#fff; transition:transform .3s var(--ease), background .3s var(--ease); }
.circle-arrow svg{ width:16px; height:16px; }

.btn{ display:inline-flex; align-items:center; gap:14px; font-weight:700; font-size:.95rem; white-space:nowrap; background:var(--blue); color:#fff; padding:16px 15px 16px 28px; border-radius:var(--r-xs); transition:transform .25s var(--ease), box-shadow .25s var(--ease), background .25s var(--ease); }
.btn:hover{ background:var(--blue-deep); transform:translateY(-2px); box-shadow:0 16px 30px -14px rgba(18,60,134,.45); }
.btn-sm{ padding:13px 13px 13px 22px; font-size:.88rem; }

/* .btn より後ろに置くことで、同specificity(0,1,0)のカスケード順で .hide-mobile を優先させる
   （.btn の display:inline-flex に上書きされないようにするため） */
@media (max-width:860px){ .hide-mobile{ display:none; } }

/* ============================================================
   FOOTER
============================================================ */
.site-footer{ background:var(--blue-deep-2); color:rgba(255,255,255,.86); padding-top:clamp(96px,10vw,132px); padding-bottom:36px; }
.footer-grid{ display:grid; grid-template-columns:1.4fr .9fr .9fr .9fr; gap:clamp(28px,4vw,48px); padding-bottom:56px; border-bottom:1px solid rgba(255,255,255,.15); }
.footer-brand .logo-word{ color:#fff; }
.footer-brand .logo-word .w-shift{ color:var(--sky-accent); }
.footer-tagline{ margin-top:22px; color:rgba(255,255,255,.72); font-size:.98rem; line-height:1.9; letter-spacing:.02em; max-width:32ch; }

.footer-col h4{ font-family:var(--font-en); font-weight:700; font-size:.74rem; letter-spacing:.14em; text-transform:uppercase; color:var(--sky-accent); margin-bottom:20px; }
.footer-col ul{ display:flex; flex-direction:column; gap:13px; }
.footer-col a{ font-size:.92rem; color:rgba(255,255,255,.82); transition:color .2s var(--ease); }
.footer-col a:hover{ color:#fff; }
.footer-col.company p{ font-size:.88rem; color:rgba(255,255,255,.78); line-height:1.95; }
.footer-col.company .co-name{ font-weight:700; color:#fff; margin-bottom:8px; display:block; }

.footer-bottom{ margin-top:32px; display:flex; flex-wrap:wrap; align-items:center; justify-content:space-between; gap:16px; }
.footer-legal{ display:flex; flex-wrap:wrap; gap:10px 24px; font-size:.82rem; }
.footer-legal a{ color:rgba(255,255,255,.72); }
.footer-legal a:hover{ color:#fff; }
.footer-copy{ font-size:.8rem; color:rgba(255,255,255,.55); }
.back-top{ display:inline-flex; align-items:center; gap:10px; font-size:.85rem; font-weight:700; color:#fff; }
.back-top .circle-arrow{ background:rgba(255,255,255,.14); }
.back-top:hover .circle-arrow{ background:var(--sky-accent); color:var(--blue-deep); transform:translateY(-3px); }

@media (max-width:900px){ .footer-grid{ grid-template-columns:1fr 1fr; } }
@media (max-width:560px){ .footer-grid{ grid-template-columns:1fr; } }