/* =========================================================
   悠遠書房 YUEN SHOBO — design system
   白基調・余白主体のモノクロ。明朝見出し + サンセリフ本文。
   ========================================================= */
:root{
  --paper:#FBFAF6;      /* warm white */
  --paper-2:#F4F1EA;    /* soft band */
  --ink:#16140F;        /* warm near-black */
  --ink-2:#2A2620;
  --muted:#7B756A;      /* warm gray */
  --muted-2:#A39C8F;
  --line:#E6E1D6;       /* hairline */
  --line-strong:#D6CFC1;

  --mincho:"Shippori Mincho", serif;
  --sans:"Noto Sans JP", system-ui, -apple-system, sans-serif;

  --maxw:1140px;
  --narrow:720px;

  --ease:cubic-bezier(.16,.84,.32,1);
  --ease-out:cubic-bezier(.22,1,.36,1);
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:var(--sans);
  color:var(--ink);
  background:var(--paper);
  line-height:1.95;
  font-weight:300;
  letter-spacing:.02em;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
::selection{background:var(--ink);color:var(--paper)}

/* ---------- layout primitives ---------- */
.container{max-width:var(--maxw);margin:0 auto;padding:0 32px}
.container.narrow{max-width:var(--narrow)}
.section{padding:clamp(90px,13vw,170px) 0;position:relative}

.eyebrow{
  font-family:var(--sans);
  font-size:.7rem;font-weight:500;
  letter-spacing:.4em;color:var(--muted);
  text-transform:uppercase;
  display:flex;align-items:center;gap:16px;
}
.eyebrow::before{
  content:"";width:34px;height:1px;background:var(--line-strong);
}
.eyebrow.center{justify-content:center}

.section-title{
  font-family:var(--mincho);
  font-weight:600;
  font-size:clamp(1.7rem,3.6vw,2.7rem);
  line-height:1.55;letter-spacing:.06em;
  margin:26px 0 0;
}

/* =========================================================
   Header
   ========================================================= */
.site-header{
  position:fixed;top:0;left:0;width:100%;z-index:200;
  background:rgba(251,250,246,0);
  backdrop-filter:blur(0px);
  border-bottom:1px solid transparent;
  transition:background .5s var(--ease),border-color .5s var(--ease),backdrop-filter .5s var(--ease);
}
.site-header.scrolled{
  background:rgba(251,250,246,.82);
  backdrop-filter:blur(14px) saturate(120%);
  border-bottom:1px solid var(--line);
}
.header-inner{
  max-width:1280px;margin:0 auto;
  padding:22px 32px;
  display:flex;align-items:center;justify-content:space-between;
}
.brand{display:flex;flex-direction:column;line-height:1.05}
.brand-mark{
  font-family:var(--mincho);font-size:1.32rem;font-weight:700;
  letter-spacing:.18em;
}
.brand-sub{
  font-size:.54rem;letter-spacing:.4em;color:var(--muted);
  margin-top:5px;padding-left:.2em;
}
.site-nav{display:flex;gap:38px;align-items:center}
.site-nav a{
  font-size:.78rem;letter-spacing:.14em;font-weight:400;
  position:relative;padding:6px 0;color:var(--ink-2);
  transition:color .3s;
}
.site-nav a::after{
  content:"";position:absolute;left:0;bottom:0;width:0;height:1px;
  background:var(--ink);transition:width .4s var(--ease);
}
.site-nav a:hover{color:var(--ink)}
.site-nav a:hover::after,.site-nav a.active::after{width:100%}

.nav-toggle{
  display:none;flex-direction:column;gap:6px;
  background:none;border:none;cursor:pointer;padding:6px;z-index:210;
}
.nav-toggle span{width:26px;height:1.5px;background:var(--ink);transition:.4s var(--ease)}
.nav-toggle.open span:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
.nav-toggle.open span:nth-child(2){opacity:0}
.nav-toggle.open span:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}

/* =========================================================
   Buttons
   ========================================================= */
.btn{
  display:inline-flex;align-items:center;gap:12px;
  padding:16px 32px;font-size:.78rem;letter-spacing:.14em;font-weight:500;
  border:1px solid var(--ink);cursor:pointer;
  position:relative;overflow:hidden;
  transition:color .45s var(--ease);
  font-family:var(--sans);
}
.btn::before{
  content:"";position:absolute;inset:0;background:var(--ink);
  transform:scaleX(0);transform-origin:left;
  transition:transform .5s var(--ease);z-index:-1;
}
.btn-dark{background:var(--ink);color:var(--paper)}
.btn-dark::before{background:var(--paper);transform:scaleX(0)}
.btn-dark:hover{color:var(--ink)}
.btn-dark:hover::before{transform:scaleX(1)}
.btn-ghost{background:transparent;color:var(--ink)}
.btn-ghost:hover{color:var(--paper)}
.btn-ghost:hover::before{transform:scaleX(1)}
.btn .arrow{font-size:.9rem;transition:transform .4s var(--ease)}
.btn:hover .arrow{transform:translateX(5px)}

/* dark band variants */
.on-dark .btn-dark{background:var(--paper);color:var(--ink);border-color:var(--paper)}
.on-dark .btn-dark::before{background:var(--ink)}
.on-dark .btn-dark:hover{color:var(--paper)}

/* =========================================================
   Hero
   ========================================================= */
.hero{
  position:relative;min-height:100svh;
  display:flex;align-items:center;
  padding:120px 0 80px;overflow:hidden;
}
.hero .container{width:100%}
.hero-grid{
  display:grid;grid-template-columns:1fr;gap:0;
  max-width:960px;
}
.hero-eyebrow{
  font-size:.68rem;letter-spacing:.42em;color:var(--muted);
  margin-bottom:38px;font-weight:500;
}
.hero-title{
  font-family:var(--mincho);font-weight:600;
  font-size:clamp(2.6rem,7.2vw,5.2rem);
  line-height:1.42;letter-spacing:.05em;
}
.hero-title .ln{display:block;overflow:hidden}
.hero-title .ln > span{display:block}
.hero-lead{
  font-size:clamp(.95rem,1.4vw,1.08rem);font-weight:300;
  color:var(--ink-2);line-height:2.1;max-width:40em;
  margin:42px 0 50px;
}
.hero-actions{display:flex;gap:18px;flex-wrap:wrap}

/* vertical side label */
.hero-side{
  position:absolute;right:48px;top:50%;transform:translateY(-50%);
  writing-mode:vertical-rl;font-feature-settings:"vpal";
  font-family:var(--mincho);letter-spacing:.5em;
  font-size:.72rem;color:var(--muted-2);
  display:flex;gap:30px;align-items:flex-start;
}
.hero-side .yr{font-family:var(--sans);letter-spacing:.3em;font-size:.62rem}

/* faint giant background character */
.hero-ghost{
  position:absolute;right:-2%;bottom:-8%;
  font-family:var(--mincho);font-weight:700;
  font-size:clamp(22rem,46vw,46rem);line-height:.8;
  color:var(--ink);opacity:.028;
  pointer-events:none;user-select:none;z-index:0;
}
.hero .container,.hero-side{position:relative;z-index:2}

.scroll-hint{
  position:absolute;bottom:34px;left:32px;
  display:flex;align-items:center;gap:14px;
  font-size:.6rem;letter-spacing:.34em;color:var(--muted);z-index:3;
}
.scroll-hint .bar{position:relative;width:54px;height:1px;background:var(--line-strong);overflow:hidden}
.scroll-hint .bar::after{content:"";position:absolute;inset:0;background:var(--ink);transform:translateX(-100%);animation:slide 2.6s var(--ease) infinite}
@keyframes slide{0%{transform:translateX(-100%)}55%{transform:translateX(0)}100%{transform:translateX(101%)}}

/* =========================================================
   Vision
   ========================================================= */
.vision .quote{
  font-family:var(--mincho);font-weight:600;
  font-size:clamp(1.9rem,4.6vw,3.4rem);
  line-height:1.6;letter-spacing:.06em;
  margin:30px 0 64px;max-width:18em;
}
.vision-body{max-width:42em;margin-left:auto}
.vision-body p{margin-bottom:26px;font-size:1rem;color:var(--ink-2)}
.vision-body p:last-child{margin-bottom:0}
.vision-body em{font-style:normal;font-weight:500;color:var(--ink);
  box-shadow:inset 0 -1px 0 var(--ink)}

/* =========================================================
   Approach — editorial rows
   ========================================================= */
.approach-list{margin-top:64px;border-top:1px solid var(--line)}
.approach-row{
  display:grid;grid-template-columns:120px 1fr 1.2fr;
  gap:40px;align-items:baseline;
  padding:48px 0;border-bottom:1px solid var(--line);
  transition:padding-left .5s var(--ease);
}
.approach-row:hover{padding-left:14px}
.approach-no{
  font-family:var(--mincho);font-size:1.3rem;color:var(--muted-2);
  letter-spacing:.1em;
}
.approach-row h3{
  font-family:var(--mincho);font-size:1.3rem;font-weight:600;
  letter-spacing:.05em;line-height:1.6;
}
.approach-row p{font-size:.92rem;color:var(--muted);line-height:2}

/* =========================================================
   Books — 刊行物
   ========================================================= */
.books-head{
  display:flex;justify-content:space-between;align-items:flex-end;
  flex-wrap:wrap;gap:24px;margin-bottom:56px;
}
.books-note{
  font-size:.74rem;letter-spacing:.2em;color:var(--muted);
  border:1px solid var(--line-strong);padding:8px 16px;
}
.book-grid{
  display:grid;grid-template-columns:repeat(4,1fr);gap:36px;
}
.book{display:flex;flex-direction:column;gap:18px}
.book-cover{
  position:relative;aspect-ratio:3/4.3;
  background:var(--paper-2);
  border:1px solid var(--line-strong);
  box-shadow:0 1px 0 var(--line) inset, 24px 24px 48px -28px rgba(22,20,15,.4);
  display:flex;align-items:center;justify-content:center;
  overflow:hidden;transition:transform .6s var(--ease),box-shadow .6s var(--ease);
}
.book:hover .book-cover{transform:translateY(-8px);box-shadow:0 1px 0 var(--line) inset,30px 34px 56px -26px rgba(22,20,15,.5)}
.book-cover::before{/* spine line */
  content:"";position:absolute;left:11px;top:0;bottom:0;width:1px;
  background:var(--line-strong);
}
.book-cover .cv-inner{
  writing-mode:vertical-rl;text-align:start;
  font-family:var(--mincho);font-weight:600;
  font-size:clamp(1rem,1.5vw,1.25rem);letter-spacing:.16em;line-height:1.5;
  color:var(--ink);height:74%;padding-left:8px;
}
.book-cover .cv-pub{
  position:absolute;bottom:14px;right:14px;
  writing-mode:vertical-rl;font-size:.5rem;letter-spacing:.32em;
  color:var(--muted-2);font-family:var(--mincho);
}
.book-cover .cv-tag{
  position:absolute;top:0;left:0;
  font-size:.5rem;letter-spacing:.24em;
  background:var(--ink);color:var(--paper);
  padding:4px 9px;
}
.book-meta .genre{font-size:.64rem;letter-spacing:.28em;color:var(--muted);text-transform:uppercase}
.book-meta .ttl{font-family:var(--mincho);font-size:.95rem;font-weight:600;margin-top:7px;letter-spacing:.04em;line-height:1.6}
.book-meta .stat{font-size:.72rem;color:var(--muted-2);margin-top:6px;letter-spacing:.1em}

/* =========================================================
   CTA band (dark)
   ========================================================= */
.band-dark{background:var(--ink);color:var(--paper)}
.band-dark .eyebrow{color:var(--muted-2)}
.band-dark .eyebrow::before{background:#4a443a}
.cta{text-align:center;position:relative;overflow:hidden}
.cta .cta-title{
  font-family:var(--mincho);font-weight:600;
  font-size:clamp(1.7rem,4vw,2.8rem);line-height:1.55;letter-spacing:.06em;
  margin:28px 0 0;
}
.cta .cta-lead{color:#c7c1b5;margin:30px auto 46px;max-width:34em;font-size:.96rem;line-height:2.05}
.cta-ghost{
  position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);
  font-family:var(--mincho);font-weight:700;
  font-size:clamp(16rem,40vw,40rem);line-height:.8;
  color:var(--paper);opacity:.025;pointer-events:none;z-index:0;
}
.cta .container{position:relative;z-index:2}

/* =========================================================
   Sub-page hero
   ========================================================= */
.page-hero{padding:200px 0 70px}
.page-hero .page-title{
  font-family:var(--mincho);font-weight:600;
  font-size:clamp(2.2rem,5vw,3.4rem);letter-spacing:.06em;
  margin-top:18px;line-height:1.4;
}
.page-hero .page-lead{color:var(--muted);margin-top:24px;max-width:34em;font-size:.96rem}
.page-hero .ja-sub{font-family:var(--mincho);color:var(--muted-2);font-size:.8rem;letter-spacing:.3em;margin-top:8px}

/* =========================================================
   Prose / Info tables
   ========================================================= */
.prose p{margin-bottom:26px;font-size:1rem;color:var(--ink-2);line-height:2.05}
.prose p:last-child{margin-bottom:0}
.prose h3{font-family:var(--mincho);font-size:1.05rem;font-weight:600;margin:34px 0 12px;letter-spacing:.04em}
.prose.small p,.prose.small h3{font-size:.9rem;line-height:1.95}

.block-title{
  font-family:var(--mincho);font-size:1.5rem;font-weight:600;
  letter-spacing:.05em;margin:0 0 32px;padding-bottom:18px;
  border-bottom:1px solid var(--line-strong);
  display:flex;align-items:baseline;gap:16px;
}
.block-title .en{font-family:var(--sans);font-size:.62rem;letter-spacing:.34em;color:var(--muted);text-transform:uppercase;font-weight:500}

.info-table dl{display:flex;flex-direction:column}
.info-table dl>div{display:flex;gap:24px;border-bottom:1px solid var(--line);padding:18px 0}
.info-table dt{flex:0 0 34%;font-weight:500;font-size:.88rem;color:var(--ink)}
.info-table dd{flex:1;color:var(--muted);font-size:.88rem;line-height:1.8}
.info-table.small dt,.info-table.small dd{font-size:.84rem}
.info-table a{box-shadow:inset 0 -1px 0 var(--line-strong)}
.note{font-size:.78rem;color:var(--muted-2);margin-top:22px;line-height:1.9}

/* =========================================================
   Form
   ========================================================= */
.form{display:flex;flex-direction:column;gap:30px;margin-bottom:40px}
.field{display:flex;flex-direction:column;gap:12px;position:relative}
.field label.lab{font-size:.84rem;font-weight:500;letter-spacing:.05em;display:flex;align-items:center;gap:10px}
.req{font-size:.58rem;background:var(--ink);color:var(--paper);padding:3px 9px;letter-spacing:.16em;font-weight:500}
.opt{font-size:.62rem;color:var(--muted-2);letter-spacing:.16em;border:1px solid var(--line-strong);padding:2px 9px}
.field input,.field select,.field textarea{
  font-family:inherit;font-size:.96rem;font-weight:300;color:var(--ink);
  padding:16px 4px;border:none;border-bottom:1px solid var(--line-strong);
  background:transparent;transition:border-color .4s var(--ease);
}
.field input:focus,.field select:focus,.field textarea:focus{outline:none;border-color:var(--ink)}
.field textarea{resize:vertical;min-height:140px;line-height:1.9}
.field select{appearance:none;cursor:pointer;background-image:linear-gradient(45deg,transparent 50%,var(--ink) 50%),linear-gradient(135deg,var(--ink) 50%,transparent 50%);background-position:calc(100% - 14px) calc(50% - 3px),calc(100% - 9px) calc(50% - 3px);background-size:5px 5px,5px 5px;background-repeat:no-repeat}
.field .err-msg{font-size:.74rem;color:#9a3b2e;letter-spacing:.04em;min-height:0;opacity:0;transform:translateY(-4px);transition:.3s}
.field.invalid input,.field.invalid textarea,.field.invalid select{border-color:#9a3b2e}
.field.invalid .err-msg{opacity:1;transform:none}
.field.check label{display:flex;align-items:flex-start;gap:12px;font-weight:300;font-size:.86rem;cursor:pointer;line-height:1.7}
.field.check input{width:17px;height:17px;margin-top:5px;accent-color:var(--ink);flex:none}
.field.check a{box-shadow:inset 0 -1px 0 var(--ink)}
.hp{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}
.form .btn{align-self:flex-start;margin-top:8px}
.form-foot{font-size:.76rem;color:var(--muted-2);margin-top:-12px;letter-spacing:.04em}

.alert{padding:22px 26px;margin-bottom:36px;font-size:.9rem;border:1px solid var(--ink);display:flex;gap:14px;align-items:flex-start}
.alert[hidden]{display:none}
.alert .ic{font-family:var(--mincho);flex:none}
.alert.success{background:var(--paper-2)}
.alert.error{background:#fbf3f3;border-color:#b23b3b;color:#7a2222}
.alert.error .ic{color:#b23b3b}

/* =========================================================
   Legal
   ========================================================= */
.legal{background:var(--paper-2);border-top:1px solid var(--line)}
.legal-block{margin-bottom:80px;scroll-margin-top:120px}
.legal-block:last-child{margin-bottom:0}

/* =========================================================
   Footer
   ========================================================= */
.site-footer{background:var(--ink);color:var(--paper);padding:90px 0 40px}
.footer-top{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:48px;padding-bottom:56px;border-bottom:1px solid #322d25}
.footer-brand .brand-mark{font-size:1.7rem;letter-spacing:.18em;color:var(--paper)}
.footer-brand .brand-sub{color:var(--muted-2);margin-top:8px;font-size:.56rem;letter-spacing:.4em}
.footer-tagline{font-family:var(--mincho);color:#c7c1b5;margin-top:28px;letter-spacing:.1em;font-size:1rem}
.footer-col h4{font-size:.62rem;letter-spacing:.3em;color:var(--muted-2);text-transform:uppercase;margin-bottom:22px;font-weight:500}
.footer-col a{display:block;font-size:.86rem;color:#d8d3c8;padding:7px 0;transition:color .3s,padding-left .3s var(--ease)}
.footer-col a:hover{color:var(--paper);padding-left:6px}
.footer-bottom{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:14px;padding-top:32px}
.copyright{font-size:.7rem;color:var(--muted-2);letter-spacing:.08em}
.footer-bottom .legalsmall{display:flex;gap:22px}
.footer-bottom .legalsmall a{font-size:.7rem;color:var(--muted-2);letter-spacing:.06em;transition:color .3s}
.footer-bottom .legalsmall a:hover{color:var(--paper)}

/* =========================================================
   Reveal / motion
   ========================================================= */
.reveal{opacity:0;transform:translateY(34px);transition:opacity 1s var(--ease-out),transform 1s var(--ease-out)}
.reveal.visible{opacity:1;transform:none}
.reveal.d1{transition-delay:.08s}
.reveal.d2{transition-delay:.16s}
.reveal.d3{transition-delay:.24s}
.reveal.d4{transition-delay:.32s}

/* line-mask reveal for hero */
.line-up{transform:translateY(115%);transition:transform 1.1s var(--ease-out)}
.hero.loaded .line-up{transform:none}
.fade-in{opacity:0;transform:translateY(20px);transition:opacity 1s var(--ease-out),transform 1s var(--ease-out)}
.hero.loaded .fade-in{opacity:1;transform:none}
.dly-1{transition-delay:.5s}.dly-2{transition-delay:.62s}.dly-3{transition-delay:.74s}.dly-4{transition-delay:.86s}.dly-5{transition-delay:.98s}

@media (prefers-reduced-motion:reduce){
  *{animation:none!important;transition-duration:.01ms!important}
  .reveal,.line-up,.fade-in{opacity:1;transform:none}
}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width:960px){
  .footer-top{grid-template-columns:1fr 1fr;gap:36px}
  .hero-side{display:none}
  .book-grid{grid-template-columns:repeat(2,1fr);gap:28px}
}
@media (max-width:768px){
  .container{padding:0 22px}
  .nav-toggle{display:flex}
  .site-nav{
    position:fixed;inset:0;background:var(--paper);
    flex-direction:column;align-items:center;justify-content:center;gap:34px;
    transform:translateX(100%);transition:transform .55s var(--ease);
  }
  .site-nav.open{transform:none}
  .site-nav a{font-size:1.15rem;letter-spacing:.12em}
  .approach-row{grid-template-columns:1fr;gap:14px;padding:36px 0}
  .approach-no{font-size:1.1rem}
  .vision-body{margin-left:0}
  .footer-top{grid-template-columns:1fr;gap:40px}
  .footer-bottom{flex-direction:column;align-items:flex-start}
  .info-table dl>div{flex-direction:column;gap:6px}
  .info-table dt{flex:none}
}
@media (max-width:520px){
  .book-grid{grid-template-columns:1fr;gap:34px;max-width:300px;margin:0 auto}
}