/* =========================================================
   yoshidayasutaka.com — 深海の静けさ
   dark deep-sea / amber accent / quiet typography
   ========================================================= */

:root {
  --sea-deepest: #04090f;
  --sea-deep: #071219;
  --sea-mid: #0b1d29;
  --ink: #e9e4d8;
  --ink-soft: rgba(233, 228, 216, 0.78);
  --ink-faint: rgba(233, 228, 216, 0.55);
  --amber: #c9a15a;
  --amber-soft: rgba(201, 161, 90, 0.65);
  --line: rgba(201, 161, 90, 0.28);
  --maxw: 42rem;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  background: var(--sea-deepest);
  color: var(--ink);
  font-family: "Shippori Mincho", "Hiragino Mincho ProN", "Yu Mincho", serif;
  font-weight: 400;
  line-height: 2.1;
  letter-spacing: 0.06em;
  font-feature-settings: "palt";
  -webkit-font-smoothing: antialiased;
}

a { color: var(--amber); text-decoration: none; transition: opacity 0.3s; }
a:hover { opacity: 0.7; }

/* ---------- nav ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 20;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  padding: 1.1rem 1.4rem;
  background: linear-gradient(to bottom, rgba(4, 9, 15, 0.92), rgba(4, 9, 15, 0));
}
.nav-name {
  font-size: 0.82rem;
  letter-spacing: 0.28em;
  color: var(--ink-soft);
}
.nav-name a { color: inherit; }
.nav-links { display: flex; gap: 1.3rem; list-style: none; }
.nav-links a {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--ink-faint);
}
.nav-links a.current { color: var(--amber); }
.nav-links .en { font-family: "EB Garamond", serif; letter-spacing: 0.12em; }

/* ---------- hero ---------- */
.hero {
  min-height: 92svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 6rem 1.5rem 4rem;
  position: relative;
  background:
    radial-gradient(ellipse 120% 65% at 50% -10%, rgba(28, 62, 84, 0.55), transparent 60%),
    radial-gradient(ellipse 90% 50% at 50% 115%, rgba(13, 34, 46, 0.8), transparent 65%),
    linear-gradient(to bottom, #0a1a26 0%, var(--sea-deep) 45%, var(--sea-deepest) 100%);
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle 1px at 20% 30%, rgba(233,228,216,0.18) 1px, transparent 1px),
    radial-gradient(circle 1px at 70% 60%, rgba(233,228,216,0.12) 1px, transparent 1px),
    radial-gradient(circle 1px at 45% 80%, rgba(201,161,90,0.15) 1px, transparent 1px),
    radial-gradient(circle 1px at 85% 25%, rgba(233,228,216,0.1) 1px, transparent 1px);
  background-size: 340px 340px, 260px 260px, 300px 300px, 380px 380px;
  pointer-events: none;
}
.hero h1 {
  font-size: clamp(1.5rem, 4.2vw, 2.3rem);
  font-weight: 500;
  line-height: 2.4;
  letter-spacing: 0.22em;
}
.hero .sub {
  margin-top: 2.4rem;
  font-family: "EB Garamond", serif;
  font-size: 0.8rem;
  letter-spacing: 0.34em;
  color: var(--amber-soft);
}
.scroll-hint {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  width: 1px;
  height: 3.2rem;
  background: linear-gradient(to bottom, transparent, var(--amber-soft));
  animation: drift 2.6s ease-in-out infinite;
}
@keyframes drift {
  0%, 100% { opacity: 0.25; transform: translateY(-4px); }
  50% { opacity: 0.9; transform: translateY(4px); }
}

/* ---------- sections ---------- */
main { display: block; }
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 5.5rem 1.5rem 0;
}
.section:last-of-type { padding-bottom: 6rem; }

.sec-label {
  font-family: "EB Garamond", serif;
  font-size: 0.74rem;
  letter-spacing: 0.3em;
  color: var(--amber-soft);
  margin-bottom: 1.2rem;
}
h2 {
  font-size: clamp(1.15rem, 3vw, 1.45rem);
  font-weight: 500;
  letter-spacing: 0.14em;
  line-height: 1.9;
  margin-bottom: 1.8rem;
}
h3 {
  font-size: 1.02rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  margin: 3.2rem 0 1.1rem;
  color: var(--ink);
}
h3 .num {
  font-family: "EB Garamond", serif;
  color: var(--amber);
  margin-right: 0.9rem;
  font-size: 1.05rem;
}
p { margin-bottom: 1.4rem; color: var(--ink-soft); font-size: 0.95rem; }
.lead { color: var(--ink); }

.divider {
  width: 2.4rem;
  height: 1px;
  background: var(--line);
  margin: 4.5rem auto 0;
  border: 0;
}

/* poem block */
.poem {
  text-align: center;
  padding: 6rem 1.5rem;
  line-height: 2.8;
  letter-spacing: 0.18em;
  font-size: clamp(1rem, 2.6vw, 1.2rem);
}
.poem .en {
  display: block;
  margin-top: 2.2rem;
  font-family: "EB Garamond", serif;
  font-size: 0.86rem;
  letter-spacing: 0.3em;
  color: var(--amber-soft);
}

/* research notes */
.refs {
  margin-top: 0.6rem;
  font-size: 0.72rem;
  line-height: 1.9;
  color: var(--ink-faint);
}
.refs a { color: var(--amber-soft); border-bottom: 1px solid transparent; }
.refs a:hover { border-bottom-color: var(--amber-soft); opacity: 1; }

/* link cards */
.links {
  margin: 1.2rem 0 0;
  padding: 0;
  list-style: none;
  font-size: 0.82rem;
}
.links li { margin-bottom: 0.35rem; color: var(--ink-faint); }
.links a { letter-spacing: 0.04em; }

/* people / encounter blocks */
.encounter {
  border-left: 1px solid var(--line);
  padding-left: 1.6rem;
  margin: 3rem 0;
}
.encounter .role {
  font-size: 0.74rem;
  letter-spacing: 0.22em;
  color: var(--amber-soft);
  margin-bottom: 0.2rem;
}
.encounter h3 { margin: 0 0 1rem; }

/* interlude — chapter closing verse */
.interlude {
  text-align: center;
  padding: 4.5rem 1.5rem;
  color: var(--ink-soft);
  line-height: 2.6;
  font-size: 0.92rem;
  letter-spacing: 0.12em;
}

/* ---------- CTA ---------- */
.cta-wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 4rem 1.5rem 7rem;
  display: grid;
  gap: 1.4rem;
}
.cta {
  display: block;
  border: 1px solid var(--line);
  padding: 1.9rem 1.7rem;
  color: var(--ink);
  background: linear-gradient(to bottom, rgba(11, 29, 41, 0.35), rgba(11, 29, 41, 0.05));
  transition: border-color 0.35s, background 0.35s;
}
.cta:hover { border-color: var(--amber-soft); opacity: 1; background: rgba(11, 29, 41, 0.5); }
.cta .t {
  font-size: 1rem;
  letter-spacing: 0.14em;
  margin-bottom: 0.5rem;
  color: var(--ink);
}
.cta .d {
  font-size: 0.8rem;
  line-height: 1.9;
  color: var(--ink-faint);
  margin: 0;
}
.cta .go {
  display: inline-block;
  margin-top: 0.9rem;
  font-size: 0.78rem;
  letter-spacing: 0.2em;
  color: var(--amber);
}

/* ---------- footer ---------- */
footer {
  border-top: 1px solid rgba(201, 161, 90, 0.15);
  padding: 3rem 1.5rem 3.5rem;
  text-align: center;
}
footer .fnav { margin-bottom: 1.6rem; font-size: 0.78rem; }
footer .fnav a { margin: 0 0.9rem; color: var(--ink-faint); }
footer small {
  display: block;
  font-family: "EB Garamond", serif;
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: rgba(233, 228, 216, 0.35);
}

/* ---------- reveal（JS有効時のみ非表示から入る） ---------- */
body.js .reveal { opacity: 0; transform: translateY(14px); transition: opacity 1.1s ease, transform 1.1s ease; }
body.js .reveal.on { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  body.js .reveal { opacity: 1; transform: none; transition: none; }
  .scroll-hint { animation: none; }
}

@media (max-width: 600px) {
  .nav-links { gap: 0.9rem; }
  .nav-links a { font-size: 0.66rem; }
  .encounter { padding-left: 1.1rem; }
}