/* ============================================================
   NEON ABYSS — style.css
   ============================================================ */

:root {
  --ink: #dfe9f4;
  --dim: #8ba1b8;
  --faint: #4c6478;
  --neon: #ffb066;
  --font-display: "Shippori Mincho B1", serif;
  --font-body: "Zen Kaku Gothic New", sans-serif;
  --font-mono: "IBM Plex Mono", monospace;
}

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

html { scroll-behavior: smooth; }

body {
  background: #04182b;
  color: var(--ink);
  font-family: var(--font-body);
  font-weight: 300;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

::selection { background: rgba(255, 176, 102, 0.35); color: #fff; }

/* ---- レイヤー ---- */

#sea {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  display: block;
}

.rays {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  mix-blend-mode: screen;
  opacity: 0.65;
  overflow: hidden;
}
.rays i {
  position: absolute;
  top: -30%;
  width: 22vw;
  height: 130vh;
  background: linear-gradient(180deg, rgba(120, 190, 235, 0.16), rgba(120, 190, 235, 0) 70%);
  transform: skewX(-14deg);
  animation: swaying 11s ease-in-out infinite alternate;
}
.rays i:nth-child(1) { left: 12%; }
.rays i:nth-child(2) { left: 42%; width: 14vw; animation-duration: 14s; animation-delay: -4s; }
.rays i:nth-child(3) { left: 70%; width: 26vw; animation-duration: 17s; animation-delay: -8s; }
@keyframes swaying {
  from { transform: skewX(-16deg) translateX(-3vw); }
  to   { transform: skewX(-10deg) translateX(3vw); }
}

.vignette {
  position: fixed;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background: radial-gradient(ellipse at 50% 45%, transparent 55%, rgba(0, 3, 9, 0.55) 100%);
}

.grain {
  position: fixed;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  opacity: 0.05;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)' opacity='0.7'/%3E%3C/svg%3E");
}

/* ---- ナビ ---- */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 26px 34px;
}
.logo {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.32em;
  color: var(--ink);
  text-decoration: none;
}
.logo span {
  display: block;
  font-family: var(--font-body);
  font-size: 0.62rem;
  letter-spacing: 0.5em;
  color: var(--dim);
  margin-top: 5px;
}
.logo:focus-visible, .cue:focus-visible {
  outline: 1px solid var(--neon);
  outline-offset: 6px;
}
.expno {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.28em;
  color: var(--faint);
}

/* ---- HUD ---- */

.depth {
  position: fixed;
  left: 34px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
}
.depth .lbl { font-size: 0.55rem; letter-spacing: 0.4em; color: var(--faint); }
.depth .num { font-size: 0.95rem; letter-spacing: 0.12em; color: var(--ink); font-weight: 500; }
.depth .unit { font-size: 0.55rem; letter-spacing: 0.3em; color: var(--faint); }
.depth .gauge {
  position: relative;
  width: 1px;
  height: 160px;
  background: linear-gradient(180deg, var(--faint), rgba(76, 100, 120, 0.15));
  margin-top: 8px;
}
.depth .gauge i {
  position: absolute;
  left: -3px;
  top: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--neon);
  box-shadow: 0 0 12px var(--neon);
}

.fishtag {
  position: fixed;
  right: 34px;
  bottom: 34px;
  z-index: 10;
  text-align: right;
  transition: opacity 0.26s ease, transform 0.26s ease;
}
.fishtag.swap { opacity: 0; transform: translateY(8px); }
.fishtag .no {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.4em;
  color: var(--faint);
}
.fishtag .jp {
  display: block;
  font-family: var(--font-display);
  font-size: 1.05rem;
  letter-spacing: 0.18em;
  margin: 6px 0 4px;
}
.fishtag .la {
  display: block;
  font-family: var(--font-mono);
  font-style: italic;
  font-size: 0.6rem;
  letter-spacing: 0.14em;
  color: var(--dim);
}

/* ---- セクション ---- */

main { position: relative; z-index: 5; }

.sec {
  position: relative;
  min-height: 160vh;
  display: flex;
  align-items: center;
  padding: 12vh 8vw;
}
.sec.hero { min-height: 100vh; align-items: center; }
.sec.last { min-height: 140vh; flex-direction: column; justify-content: center; gap: 14vh; }

.inner { max-width: 560px; }
.inner.center { margin: 0 auto; text-align: center; }
.inner.left { margin-right: auto; }
.inner.right { margin-left: auto; }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.4em;
  color: var(--dim);
  margin-bottom: 26px;
}

h1, h2 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.32;
  letter-spacing: 0.06em;
  text-shadow: 0 0 40px rgba(80, 160, 220, 0.25);
}
h1 { font-size: clamp(2.4rem, 6.4vw, 4.8rem); }
h2 { font-size: clamp(1.8rem, 4.6vw, 3.4rem); }

.lead, .body {
  margin-top: 30px;
  font-size: 0.95rem;
  line-height: 2.3;
  letter-spacing: 0.06em;
  color: var(--dim);
}
.inner.center .lead { max-width: 460px; margin-left: auto; margin-right: auto; }

/* データストリップ */
.data {
  display: flex;
  gap: 44px;
  margin-top: 40px;
  border-top: 1px solid rgba(139, 161, 184, 0.2);
  padding-top: 22px;
}
.data dt {
  font-size: 0.62rem;
  letter-spacing: 0.34em;
  color: var(--faint);
  margin-bottom: 8px;
}
.data dd {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  letter-spacing: 0.1em;
}

/* 縦書きキャプション */
.vtx {
  position: absolute;
  right: 7vw;
  top: 50%;
  transform: translateY(-50%);
  writing-mode: vertical-rl;
  font-size: 0.68rem;
  letter-spacing: 0.55em;
  color: var(--faint);
}
.vtx.lft { right: auto; left: 7vw; }

/* 潜行ボタン */
.cue {
  margin-top: 54px;
  background: none;
  border: 1px solid rgba(223, 233, 244, 0.28);
  border-radius: 999px;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 0.8rem;
  letter-spacing: 0.34em;
  padding: 16px 34px 16px 40px;
  cursor: pointer;
  transition: border-color 0.4s ease, box-shadow 0.4s ease, background 0.4s ease;
}
.cue:hover {
  border-color: var(--neon);
  box-shadow: 0 0 26px rgba(255, 176, 102, 0.25), inset 0 0 18px rgba(255, 176, 102, 0.08);
}
.cue .arr {
  display: inline-block;
  margin-left: 14px;
  animation: bob 1.8s ease-in-out infinite;
}
@keyframes bob {
  0%, 100% { transform: translateY(-2px); }
  50% { transform: translateY(4px); }
}

/* 締め */
.fin {
  margin-top: 60px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.5em;
  color: var(--dim);
}
.credit {
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.26em;
  color: var(--faint);
  line-height: 2.4;
}

/* ---- リビール ---- */

.rv {
  opacity: 0;
  transform: translateY(30px);
  filter: blur(8px);
  transition: opacity 1.1s cubic-bezier(0.2, 0.7, 0.2, 1),
              transform 1.1s cubic-bezier(0.2, 0.7, 0.2, 1),
              filter 1.1s cubic-bezier(0.2, 0.7, 0.2, 1);
}
.rv.in { opacity: 1; transform: none; filter: none; }
.rv.d1 { transition-delay: 0.12s; }
.rv.d2 { transition-delay: 0.26s; }
.rv.d3 { transition-delay: 0.42s; }

body:not(.loaded) .hero .rv { transition-delay: 0.6s; }

/* ---- レスポンシブ ---- */

@media (max-width: 720px) {
  .nav { padding: 20px 22px; }
  .expno { display: none; }
  .depth { left: 18px; }
  .depth .gauge { height: 110px; }
  .fishtag { right: 20px; bottom: 22px; }
  .sec { padding: 14vh 9vw; min-height: 150vh; }
  .vtx { display: none; }
  .inner.left, .inner.right { margin: 0; }
  .lead, .body { font-size: 0.88rem; line-height: 2.1; }
  .data { gap: 28px; }
}

/* ---- reduced motion ---- */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .rv { transition: none; opacity: 1; transform: none; filter: none; }
  .rays i, .cue .arr { animation: none; }
}