/* =========================================================
   バーチャル・シンクタンク NVRI — Brutalist Editorial System
   ========================================================= */

:root {
  /* ---- Palette (base: クール×ホワイト + バイオレット) ---- */
  --paper:    #E4E9F1;   /* cool gray page */
  --paper-2:  #D7DEE8;   /* slightly darker panel */
  --paper-3:  #FFFFFF;   /* pure white cards / bands */
  --ink:      #0F1320;   /* near-black navy */
  --ink-soft: #3A3F4E;
  --blue:     #5B2BE0;   /* accent — violet */
  --acid:     #C8F133;   /* acid lime */
  --red:      #FF3B16;   /* alarm accent (used sparingly) */

  /* ---- Type ---- */
  --gothic: "Zen Kaku Gothic New", "Noto Sans JP", sans-serif;
  --mincho: "Shippori Mincho B1", "Shippori Mincho", serif;
  --mono:   "Space Mono", ui-monospace, monospace;
  --body:   "Noto Sans JP", sans-serif;

  /* ---- Structure ---- */
  --line: 2px solid var(--ink);
  --line-thick: 4px solid var(--ink);
  --gutter: clamp(16px, 4vw, 56px);
  --maxw: 1500px;
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--body);
  background: var(--paper);
  color: var(--ink);
  line-height: 1.6;
  font-feature-settings: "palt" 1;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--blue); color: var(--paper); }

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }

/* ---- Reusable type ---- */
.mono {
  font-family: var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.72rem;
}
.label {
  font-family: var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.7rem;
  font-weight: 700;
}
/* keep a phrase from breaking mid-word (e.g. long katakana terms) */
.nowrap { white-space: nowrap; }

/* ---- Layout primitives ---- */
.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding-inline: var(--gutter);
}
.section { position: relative; }

/* full-bleed top border between sections */
.rule-top { border-top: var(--line-thick); }
.rule-bot { border-bottom: var(--line-thick); }

/* ---- Grid background lines for brutalist feel ---- */
.gridlines {
  position: absolute; inset: 0; pointer-events: none; z-index: 0;
  background-image:
    linear-gradient(to right, color-mix(in srgb, var(--ink) 8%, transparent) 1px, transparent 1px);
  background-size: calc(100% / 6) 100%;
}

/* ---- Scroll reveal ---- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .7s cubic-bezier(.16,.84,.34,1), transform .7s cubic-bezier(.16,.84,.34,1);
}
.reveal.in { opacity: 1; transform: none; }
.reveal.d1 { transition-delay: .08s; }
.reveal.d2 { transition-delay: .16s; }
.reveal.d3 { transition-delay: .24s; }
.reveal.d4 { transition-delay: .32s; }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex; align-items: center; gap: .6em;
  font-family: var(--mono); font-weight: 700;
  text-transform: uppercase; letter-spacing: .06em;
  font-size: .82rem;
  padding: .85em 1.4em;
  border: var(--line);
  background: var(--ink); color: var(--paper);
  cursor: pointer;
  transition: background .18s, color .18s, transform .12s;
}
.btn:hover { background: var(--blue); color: #fff; border-color: var(--blue); }
.btn:active { transform: translate(2px, 2px); }
.btn--ghost { background: transparent; color: var(--ink); }
.btn--ghost:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.btn .arr { transition: transform .18s; }
.btn:hover .arr { transform: translateX(4px); }

/* ---- Focus visibility (WCAG 2.4.7) ---- */
a:focus-visible, button:focus-visible, .btn:focus-visible,
input:focus-visible, select:focus-visible, textarea:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--blue); outline-offset: 2px;
}
/* ---- Skip link (keyboard a11y) ---- */
.skip-link {
  position: absolute; left: 8px; top: -56px; z-index: 200;
  background: var(--ink); color: var(--paper);
  font-family: var(--mono); font-size: .78rem; font-weight: 700;
  letter-spacing: .04em; padding: .6em 1em; border: var(--line);
  transition: top .15s;
}
.skip-link:focus { top: 8px; }