/* AQUAPLUS — editorial visual-novel, indigo + gold, slender serif accents */
:root{
  --deep:#1a1c33; --deep2:#262a4a; --ink:#24263b; --mut:#6c6f87;
  --gold:#c9a24b; --gold2:#e7c87a; --paper:#f7f5ef; --card:#fffdf7; --line:#e4dfd0;
  --maxw:1120px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{background:var(--paper);color:var(--ink);font-family:"Noto Serif JP","Hiragino Mincho ProN","Yu Mincho",serif;line-height:1.85}
h1,h2,h3,.sans{font-family:"Noto Sans JP","Hiragino Kaku Gothic ProN","Yu Gothic UI",system-ui,sans-serif}
a{color:inherit;text-decoration:none}
img{max-width:100%;height:auto;display:block}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}

header.site{position:sticky;top:0;z-index:60;background:rgba(26,28,51,.96);color:#fff;border-bottom:1px solid rgba(201,162,75,.35)}
.top{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo{display:flex;align-items:baseline;gap:10px;font-weight:700;letter-spacing:.16em;color:var(--gold2)}
.logo b{font-size:1.2rem}
.logo small{font-size:.68rem;color:#b9bdd6;letter-spacing:.2em}
nav.menu{display:flex;gap:20px;align-items:center}
nav.menu a{font-family:"Noto Sans JP",sans-serif;font-size:.92rem;color:#ccd0e2;font-weight:600}
nav.menu a:hover,nav.menu a.active{color:var(--gold2)}
nav.menu .btn{background:var(--gold);color:#20233c;padding:9px 20px;border-radius:4px;font-weight:800}
.nav-toggle{display:none;background:none;border:1px solid rgba(201,162,75,.5);color:var(--gold2);font-size:1.5rem;border-radius:6px;width:42px;height:42px;cursor:pointer}

.hero{color:#fff;background:radial-gradient(900px 500px at 80% -10%, rgba(201,162,75,.3) 0, transparent 55%),linear-gradient(160deg,var(--deep),var(--deep2));padding:86px 0 70px}
.hero .tag{display:inline-block;letter-spacing:.3em;font-size:.78rem;color:var(--gold2);border:1px solid rgba(201,162,75,.5);padding:7px 18px;border-radius:2px;margin-bottom:26px}
.hero h1{font-family:"Noto Sans JP",sans-serif;font-size:clamp(2.1rem,5.6vw,3.7rem);font-weight:800;line-height:1.2;letter-spacing:.02em}
.hero h1 .g{color:var(--gold2)}
.hero .sub{margin-top:22px;max-width:660px;color:#c9cde0;font-size:1.06rem;line-height:1.9}
.cta-row{margin-top:34px;display:flex;gap:16px;flex-wrap:wrap}
.btn{display:inline-block;background:var(--gold);color:#20233c;padding:14px 34px;border-radius:4px;font-weight:800;font-size:.95rem;font-family:"Noto Sans JP",sans-serif;transition:transform .15s}
.btn:hover{transform:translateY(-2px)}
.btn.ghost{background:transparent;border:1px solid var(--gold);color:var(--gold2)}
.btn.ghost:hover{background:var(--gold);color:#20233c}

/* series ribbon */
.sri{margin-top:44px;display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.sri .s{background:rgba(255,255,255,.05);border:1px solid rgba(201,162,75,.3);padding:16px 18px;border-radius:2px}
.sri .s b{display:block;font-family:"Noto Sans JP",sans-serif;color:#fff;font-size:.98rem}
.sri .s span{font-size:.78rem;color:#aeb3cd}

section.blk{padding:60px 0}
section.blk.alt{background:#efece1}
h2.sec{font-family:"Noto Sans JP",sans-serif;font-size:1.55rem;font-weight:800;color:var(--deep);margin-bottom:8px;letter-spacing:.02em}
h2.sec .en{display:block;font-size:.72rem;letter-spacing:.3em;color:var(--gold);font-weight:600;margin-top:4px}
p.sec-sub{color:var(--mut);margin-bottom:30px;max-width:660px}
.grid{display:grid;gap:20px}
.g2{grid-template-columns:repeat(2,1fr)}
.g3{grid-template-columns:repeat(3,1fr)}
.g4{grid-template-columns:repeat(4,1fr)}
.wk{background:var(--card);border:1px solid var(--line);border-radius:6px;padding:28px;box-shadow:0 8px 22px rgba(38,42,74,.06)}
.wk .ic{font-size:1.8rem;margin-bottom:12px}
.wk h3{font-family:"Noto Sans JP",sans-serif;font-size:1.1rem;margin-bottom:6px;color:var(--deep)}
.wk p{color:var(--mut);font-size:.93rem}
.wk .yr{display:inline-block;margin-top:10px;font-size:.78rem;color:var(--gold);font-weight:700}

/* quote divider */
.quote{border-left:3px solid var(--gold);padding:6px 0 6px 22px;max-width:760px;margin:0 auto;color:var(--deep);font-size:1.06rem}
.quote em{font-style:normal;color:var(--gold)}

/* subpage */
.phead{padding:54px 0 30px;background:linear-gradient(160deg,var(--deep),var(--deep2));color:#fff}
.crumb{font-size:.85rem;color:#aeb3cd;margin-bottom:14px}
.crumb a{color:var(--gold2)}
.phead h1{font-family:"Noto Sans JP",sans-serif;font-size:clamp(1.8rem,4.4vw,2.9rem);font-weight:800}
.lede{margin-top:12px;max-width:720px;color:#c9cde0;font-size:1.04rem}
article.prose{max-width:880px}
article.prose h2{font-family:"Noto Sans JP",sans-serif;font-size:1.35rem;margin:34px 0 12px;color:var(--deep)}
article.prose p{margin-bottom:15px;color:#3a3d55}
article.prose ul{margin:0 0 18px 22px;color:#3a3d55}
article.prose ul li{margin-bottom:8px}
article.prose .note{background:#f3efe3;border-left:4px solid var(--gold);padding:16px 20px;color:#6c6f87;font-size:.92rem}

details.faq{background:var(--card);border:1px solid var(--line);border-radius:6px;overflow:hidden;margin-bottom:10px;max-width:880px}
details.faq summary{padding:17px 22px;cursor:pointer;font-family:"Noto Sans JP",sans-serif;font-weight:800;color:var(--deep);list-style:none}
details.faq summary::-webkit-details-marker{display:none}
details.faq[open]{border-color:var(--gold)}
details.faq .a{padding:2px 22px 18px;color:var(--mut);font-size:.95rem}

.band{background:linear-gradient(135deg,var(--deep),var(--deep2));border:1px solid rgba(201,162,75,.4);border-radius:8px;padding:46px 40px;text-align:center;color:#fff}
.band h2{font-family:"Noto Sans JP",sans-serif;font-size:1.5rem}
.band .btn{margin-top:22px}
footer.site{background:var(--deep);color:#aeb3cd;border-top:3px solid var(--gold);margin-top:58px;padding:46px 0 38px;font-size:.9rem}
.ft{display:flex;justify-content:space-between;gap:28px;flex-wrap:wrap}
.ft .logo{color:var(--gold2);margin-bottom:8px}
.ft nav{display:flex;gap:18px;flex-wrap:wrap}
.ft nav a:hover{color:var(--gold2)}

@media(max-width:880px){
  .g3,.g4{grid-template-columns:1fr}
  .g2{grid-template-columns:1fr}
  .sri{grid-template-columns:repeat(2,1fr)}
  nav.menu{display:none;flex-direction:column;background:var(--deep);position:fixed;top:68px;left:0;right:0;padding:14px;border-bottom:1px solid rgba(201,162,75,.35);gap:14px}
  nav.menu.open{display:flex}
  .nav-toggle{display:block}
  .hero{padding:56px 0 46px}
}