@font-face {
  font-family: "ExpletusSans";
  src: url("../font/ExpletusSans-Regular.ttf") format("truetype");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "Inter18";
  src: url("../font/Inter-18pt-Regular.ttf") format("truetype");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

:root {
  --navy: #19233B;
  --cyan: #4BB9E8;
  --cyan-d: #4A90E2;
  --violet: #80309F;
  --green: #2E8B68;
  --muted: #6A768D;
  --card: #F7F8FB;
  --card-2: #F3F6FA;
  --tint-c: #E9F6FD;
  --tint-v: #F3EAF8;
  --tint-g: #EAF7F1;
  --line: #D7DDEA;
  --white: #FFFFFF;
  --dark: #2B2B2B;
  --dark-2: #333333;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Inter18", "Segoe UI", system-ui, sans-serif;
  color: var(--navy);
  background: var(--white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--cyan-d); text-decoration: none; }
a:hover { color: var(--violet); }
:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}
.skip:focus-visible { outline-offset: 0; }
.wrap { width: min(1100px, 90%); margin: 0 auto; }
h1, h2, h3, .brand, .splash-title {
  font-family: "ExpletusSans", "Palatino Linotype", Georgia, serif;
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--navy);
}
code, pre { font-family: "Cascadia Code", Consolas, ui-monospace, monospace; }
code { font-size: .9em; background: var(--tint-c); padding: .05em .35em; border-radius: 4px; color: var(--navy); }
pre {
  background: var(--navy); color: #E8E0D2;
  padding: 1rem 1.1rem; overflow: auto; border-radius: 8px;
  font-size: .82rem; line-height: 1.45; margin: 1rem 0 1.4rem;
}
pre code { background: none; color: inherit; padding: 0; }
table { width: 100%; border-collapse: collapse; font-size: .92rem; margin: 1rem 0 1.5rem; }
th, td { border-bottom: 1px solid var(--line); padding: .55rem .65rem; text-align: left; vertical-align: top; }
th { background: var(--card); color: var(--navy); }
.skip {
  position: absolute; left: -999px; top: 0;
}
.skip:focus { left: 8px; top: 8px; background: var(--white); padding: .4rem .8rem; z-index: 99; }

/* top bar — 00.png / 01.png split cyan | violet */
.topbar {
  height: 5px;
  background: linear-gradient(90deg, var(--cyan) 0 50%, var(--violet) 50% 100%);
}

/* splash / home dark */
body.theme-dark {
  background: var(--dark);
  color: #f4f4f4;
}
body.theme-dark h1, body.theme-dark h2, body.theme-dark h3, body.theme-dark .brand { color: #fff; }
body.theme-dark a { color: var(--cyan); }
body.theme-dark a:hover { color: #fff; }
body.theme-dark a.pill,
body.theme-dark a.lang-btn { color: #fff; }
body.theme-dark a.pill:hover,
body.theme-dark a.lang-btn:hover { color: #fff; }
body.theme-dark a.pill span,
body.theme-dark a.lang-btn .s { color: #cfcfcf; }

.splash {
  min-height: 100vh;
  position: relative;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--dark) url("../image/back.png") center / cover no-repeat;
}
.splash::before {
  content: "";
  position: absolute; inset: 0;
  background: rgba(30,30,30,.55);
}
.splash-inner, .home-hero {
  position: relative; z-index: 2;
  width: min(1100px, 90%);
  margin: 0 auto;
  padding: 2.2rem 0 8rem;
}
.hdr-dark {
  position: relative; z-index: 3;
  display: flex; align-items: center; gap: 1rem;
  padding: 1.4rem 0 2rem;
}
.logo-h { width: 56px; height: 56px; }
.kicker {
  color: var(--cyan); font-size: .82rem; letter-spacing: .12em;
  text-transform: uppercase; font-family: "Inter18", sans-serif;
}
.splash-title {
  font-size: clamp(3rem, 9vw, 5.1rem);
  color: #fff; margin: .35rem 0 1.1rem;
  letter-spacing: -0.03em;
}
.tagline {
  font-family: "ExpletusSans", serif;
  font-style: italic;
  color: var(--cyan);
  font-size: clamp(1.2rem, 2.7vw, 1.65rem);
  max-width: 38rem;
  margin-bottom: .85rem;
  line-height: 1.35;
  overflow-wrap: anywhere;
}
.subline { color: #eee; margin-bottom: 1.8rem; font-size: 1.08rem; }
.home-note { color: #b8b8b8; font-size: .92rem; margin-top: 1.4rem; }
.pills {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: .85rem;
  max-width: 46rem;
}
.pill {
  background: rgba(255,255,255,.08);
  border: 0;
  color: #fff;
  padding: 1rem 1.1rem;
  text-align: center;
  border-radius: 2px;
  display: flex; flex-direction: column; gap: .25rem; justify-content: center;
  min-height: 3.4rem;
  transition: background .2s, transform .2s;
}
.pill:hover { background: rgba(75,185,232,.22); color: #fff; transform: translateY(-2px); }
.pill strong { font-size: 1.02rem; font-weight: 600; }
.pill span { font-size: .76rem; color: #cfcfcf; }
.lang-row { display: flex; flex-wrap: wrap; gap: .8rem; }
.lang-btn {
  background: rgba(255,255,255,.07);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: 10px;
  padding: 1rem 1.2rem;
  min-width: 128px;
  color: #fff;
  display: flex; flex-direction: column; align-items: center; gap: .35rem;
  transition: .2s;
}
.lang-btn:hover { border-color: var(--cyan); background: rgba(75,185,232,.15); color: #fff; }
.lang-btn .f { font-size: 1.6rem; font-family: "Segoe UI Emoji", "Apple Color Emoji", "Noto Color Emoji", sans-serif; line-height: 1.2; }
.lang-btn .n { font-weight: 600; }
.lang-btn .s { font-size: .72rem; color: #bbb; }

.wave {
  position: absolute; left: 0; right: 0; bottom: 0;
  width: 100%; height: 150px; object-fit: cover; object-position: bottom;
  pointer-events: none; z-index: 1;
}
.logo-f {
  position: absolute; right: 5%; bottom: 22px; z-index: 2;
  width: 110px; height: auto;
}

/* light header */
.hdr {
  position: sticky; top: 0; z-index: 40;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.hdr-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; padding: .7rem 0;
}
.brand-lock { display: flex; align-items: center; gap: .7rem; color: var(--violet); }
.brand-lock img { width: 42px; height: 42px; }
.brand-lock .name { font-family: "ExpletusSans", serif; font-size: 1.15rem; color: var(--violet); }
.nav { display: flex; gap: 1.2rem; align-items: center; flex-wrap: wrap; }
.nav a { color: var(--navy); font-size: .92rem; }
.nav a.on, .nav a:hover { color: var(--violet); }
.burger { display: none; background: none; border: 0; font-size: 1.4rem; cursor: pointer; color: var(--navy); }

main.page { padding: 2.2rem 0 4rem; }
.page-kicker { color: var(--cyan-d); font-size: .8rem; letter-spacing: .14em; text-transform: uppercase; margin-bottom: .4rem; }
h1 { font-size: clamp(1.7rem, 4vw, 2.4rem); margin-bottom: .8rem; }
.page h2 { font-size: 1.32rem; margin: 1.85rem 0 .65rem; }
.page h3 { font-size: 1.08rem; margin: 1.25rem 0 .45rem; }
.page p { margin-bottom: .85rem; }
.page ul, .page ol { margin: 0 0 1.15rem 1.2rem; }
.page li { margin-bottom: .32rem; }
.lead { font-size: 1.12rem; color: var(--muted); margin-bottom: 1.6rem; max-width: 46rem; }
.phrase {
  font-family: "ExpletusSans", serif;
  font-size: clamp(1.25rem, 2.4vw, 1.7rem);
  line-height: 1.4;
  margin: 0 0 1.4rem;
}

.layout { display: grid; grid-template-columns: 230px 1fr; gap: 2.2rem; align-items: start; }
.side {
  position: sticky; top: 72px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: .8rem;
  max-height: calc(100vh - 90px);
  overflow: auto;
}
.side a { display: block; padding: .28rem .4rem; color: var(--navy); font-size: .82rem; border-radius: 4px; }
.side a.on { background: var(--tint-v); color: var(--violet); }
.side a:hover { background: var(--tint-c); }
.side .lab { font-size: .68rem; letter-spacing: .12em; text-transform: uppercase; color: var(--violet); padding: .5rem .4rem .2rem; }

.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin: 1.2rem 0 1.6rem; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 1.2rem 1.15rem 1.3rem;
}
.card .num { font-family: "ExpletusSans", serif; font-size: 1.7rem; color: var(--cyan-d); }
.card h3 { margin: .2rem 0 .45rem; font-size: 1.05rem; }
.card p { color: var(--muted); font-size: .92rem; }
.card .u {
  text-decoration: underline;
  text-underline-offset: 5px;
  text-decoration-thickness: 1.5px;
  text-decoration-color: var(--cyan);
  color: var(--navy);
}

.band {
  background: var(--navy);
  color: #fff;
  padding: 1.15rem 1.4rem;
  margin: 1.6rem 0;
  border-radius: 0;
}
.band strong { color: var(--cyan); }
.call {
  border-left: 4px solid var(--cyan);
  background: var(--tint-c);
  padding: .9rem 1rem;
  margin: 1.1rem 0;
}
.call.violet { border-color: var(--violet); background: var(--tint-v); }
.call.green { border-color: var(--green); background: var(--tint-g); }
.call.trap { border-color: #BC5A4B; background: #FCEDE9; }

.hl-c { color: var(--cyan-d); }
.hl-v { color: var(--violet); }
.hl-g { color: var(--green); }

.pager { display: flex; justify-content: space-between; gap: 1rem; margin-top: 2.2rem; flex-wrap: wrap; }
.pager a { background: var(--card); border: 1px solid var(--line); padding: .7rem 1rem; border-radius: 6px; color: var(--navy); }
.pager a:hover { border-color: var(--violet); }

.ftr {
  position: relative;
  background: #2A2A2A;
  color: #d7ddea;
  padding: 5.2rem 0 1.6rem;
  overflow: visible;
  margin-top: 4.5rem;
}
.ftr .wrap { position: relative; z-index: 2; display: grid; grid-template-columns: 1fr auto; gap: 1.5rem; align-items: end; }
.ftr a { color: var(--cyan); }
.ftr-copy { margin-top: 1.2rem; font-size: .82rem; color: #9aa3b5; }
.ftr-logo { width: 88px; }
.ftr-wave {
  position: absolute; left: 0; right: 0; top: -110px; width: 100%; height: 160px;
  object-fit: cover; object-position: bottom; pointer-events: none;
}

.hub-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: .65rem; }
.hub-grid a {
  display: block; background: var(--card); border: 1px solid var(--line);
  padding: .85rem 1rem; border-radius: 6px; color: var(--navy);
}
.hub-grid a:hover { border-color: var(--violet); color: var(--violet); }
.hub-grid small { display: block; color: var(--muted); font-size: .78rem; }

.pre-wrap { position: relative; }
.pre-wrap pre { padding-top: 2.2rem; }
.copy-json {
  position: absolute; top: 8px; right: 8px;
  background: rgba(255,255,255,.12); color: #fff;
  border: 0; border-radius: 4px; padding: .25rem .55rem;
  font: inherit; font-size: .72rem; cursor: pointer;
}
.copy-json:hover { background: rgba(75,185,232,.35); }

.checks { display: flex; flex-wrap: wrap; gap: .6rem 1.1rem; margin: .4rem 0 1.2rem; color: var(--muted); }
.checks span::before { content: "✓ "; color: var(--green); font-weight: 700; }

@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; }
  .side { position: static; max-height: 220px; }
  .cards { grid-template-columns: 1fr; }
  .hub-grid { grid-template-columns: 1fr; }
  .pills { grid-template-columns: 1fr; max-width: 22rem; }
  .tagline { font-size: clamp(1rem, 4.8vw, 1.28rem); max-width: 100%; }
  .splash-title { font-size: clamp(2.2rem, 12vw, 3.2rem); }
  .home-note { font-size: .86rem; }
  .burger { display: block; }
  .nav { display: none; }
  .nav.open { display: flex; flex-direction: column; position: absolute; right: 5%; top: 58px; background: #fff; border: 1px solid var(--line); padding: 1rem; z-index: 50; }
  .ftr .wrap { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}