/* =========================================================
   Roblox AI Model Lab — styles
   白基調 / 青アクセント / ドキュメント風 / レスポンシブ
   ========================================================= */

:root {
  --bg:        #ffffff;
  --bg-soft:   #f6f8fc;
  --bg-tint:   #eef4ff;
  --ink:       #12161d;
  --ink-2:     #4d5765;
  --ink-3:     #8b94a3;
  --line:      #e6eaf1;
  --line-2:    #d7dde8;

  --blue:      #1f6feb;
  --blue-d:    #155bc4;
  --blue-12:   rgba(31, 111, 235, 0.12);

  --green:     #1f9d57;
  --green-bg:  #e7f6ee;
  --amber:     #b9791a;
  --amber-bg:  #fbf1de;
  --slate:     #5b6573;
  --slate-bg:  #eef1f6;

  --maxw:      1080px;
  --radius:    12px;
  --radius-sm: 8px;

  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --sans: "Noto Sans JP", system-ui, -apple-system, "Hiragino Kaku Gothic ProN",
          "Yu Gothic", Meiryo, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.85;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }

img { max-width: 100%; display: block; }

h1, h2, h3, h4 { line-height: 1.4; font-weight: 700; margin: 0; letter-spacing: .01em; }

p { margin: 0; }

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---- mono label / eyebrow ---- */
.eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--blue);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--blue);
}

/* =========================================================
   Header
   ========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  font-weight: 700;
  letter-spacing: .005em;
}
.brand .logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--blue);
  color: #fff;
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-size: 14px;
  font-weight: 700;
  flex: none;
}
.brand .brand-name { font-size: 16px; }
.brand .brand-sub {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .12em;
  color: var(--ink-3);
  text-transform: uppercase;
  display: block;
  line-height: 1;
  margin-top: 2px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 26px;
}
.nav a {
  font-size: 14px;
  color: var(--ink-2);
  transition: color .15s;
}
.nav a:hover { color: var(--blue); }
/* nav内のCTAボタンはデスクトップでは隠す（header-ctaとの重複防止） */
.nav > .btn { display: none; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  font-weight: 600;
  padding: 9px 16px;
  border-radius: 999px;
  transition: background .15s, color .15s, border-color .15s, transform .1s;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: var(--blue-d); }
.btn-ghost {
  border: 1px solid var(--line-2);
  color: var(--ink);
  background: #fff;
}
.btn-ghost:hover { border-color: var(--blue); color: var(--blue); }

.nav-toggle { display: none; }

/* =========================================================
   Hero
   ========================================================= */
.hero {
  padding: 84px 0 72px;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(900px 380px at 85% -10%, var(--bg-tint), transparent 70%);
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 56px;
  align-items: center;
}
.hero h1 {
  font-size: clamp(28px, 4.6vw, 46px);
  line-height: 1.32;
  letter-spacing: .005em;
  margin: 20px 0 22px;
  text-wrap: balance;
}
.hero h1 .hl {
  color: var(--blue);
  background: linear-gradient(transparent 62%, var(--blue-12) 62%);
  padding: 0 2px;
}
.hero-lead {
  font-size: 17px;
  color: var(--ink-2);
  max-width: 36em;
}
.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}
.hero-cta .btn { padding: 12px 22px; font-size: 15px; }
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 8px;
  margin-top: 30px;
}
.chip {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--ink-2);
  background: var(--bg-soft);
  border: 1px solid var(--line);
  padding: 5px 11px;
  border-radius: 999px;
}

/* placeholder visual */
.ph {
  position: relative;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background-color: var(--bg-soft);
  background-image:
    repeating-linear-gradient(135deg, #eef2f8 0 10px, #f7f9fc 10px 20px);
  display: grid;
  place-items: center;
  overflow: hidden;
}
.ph .ph-tag {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-3);
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid var(--line);
  padding: 6px 12px;
  border-radius: 6px;
  letter-spacing: .02em;
}
.hero-visual {
  aspect-ratio: 4 / 3.4;
  box-shadow: 0 20px 50px -28px rgba(20, 40, 90, 0.35);
}
.hero-visual .badge {
  position: absolute;
  top: 14px;
  left: 14px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--blue);
  background: #fff;
  border: 1px solid var(--line);
  padding: 5px 10px;
  border-radius: 6px;
}

/* =========================================================
   Section base
   ========================================================= */
section { scroll-margin-top: 80px; }
.section { padding: 78px 0; }
.section.soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 44em; margin-bottom: 40px; }
.section-head h2 {
  font-size: clamp(23px, 3vw, 31px);
  margin: 14px 0 12px;
  letter-spacing: .01em;
}
.section-head p { color: var(--ink-2); font-size: 16px; }

/* =========================================================
   About
   ========================================================= */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 20px;
  margin-top: 8px;
}
.about-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px;
}
.about-card .num {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--blue);
  letter-spacing: .1em;
}
.about-card h3 { font-size: 17px; margin: 12px 0 8px; }
.about-card p { color: var(--ink-2); font-size: 14.5px; }

.callout {
  margin-top: 30px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
  background: var(--bg-tint);
  border: 1px solid #d6e3fb;
  border-left: 3px solid var(--blue);
  border-radius: var(--radius-sm);
  padding: 20px 22px;
}
.callout .ic {
  font-family: var(--mono);
  font-weight: 700;
  color: var(--blue);
  flex: none;
  font-size: 14px;
  margin-top: 1px;
}
.callout p { font-size: 14.5px; color: var(--ink); }
.callout strong { color: var(--blue-d); }

/* =========================================================
   Categories
   ========================================================= */
.cat-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.cat-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 22px;
  transition: border-color .15s, box-shadow .2s, transform .15s;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.cat-card:hover {
  border-color: var(--blue);
  box-shadow: 0 14px 34px -22px rgba(31, 111, 235, 0.5);
  transform: translateY(-2px);
}
.cat-icon {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  background: var(--bg-tint);
  color: var(--blue);
  display: grid;
  place-items: center;
  flex: none;
}
.cat-icon svg { width: 22px; height: 22px; }
.cat-step {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--ink-3);
}
.cat-card h3 { font-size: 18px; }
.cat-card p { color: var(--ink-2); font-size: 14px; }
.cat-card .cat-tags {
  margin-top: auto;
  padding-top: 6px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.cat-tags .t {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-2);
  background: var(--bg-soft);
  border: 1px solid var(--line);
  padding: 3px 8px;
  border-radius: 5px;
}

/* =========================================================
   Logs
   ========================================================= */
.log-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}
.log-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: border-color .15s, box-shadow .2s;
}
.log-card:hover { border-color: var(--line-2); box-shadow: 0 12px 30px -24px rgba(20,40,90,.4); }
.log-thumb {
  aspect-ratio: 16 / 7.4;
  border-bottom: 1px solid var(--line);
}
.log-body { padding: 20px 22px 22px; display: flex; flex-direction: column; gap: 11px; flex: 1; }
.log-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-3);
}
.tag {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .03em;
  padding: 3px 9px;
  border-radius: 5px;
  font-weight: 500;
}
.tag-cat { color: var(--blue); background: var(--bg-tint); }
.status {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-family: var(--mono);
  font-size: 11px;
  padding: 3px 9px;
  border-radius: 999px;
  font-weight: 500;
}
.status::before { content: ""; width: 6px; height: 6px; border-radius: 50%; }
.status.solved { color: var(--green); background: var(--green-bg); }
.status.solved::before { background: var(--green); }
.status.testing { color: var(--amber); background: var(--amber-bg); }
.status.testing::before { background: var(--amber); }
.status.retest { color: var(--slate); background: var(--slate-bg); }
.status.retest::before { background: var(--slate); }
.log-card h3 { font-size: 17.5px; line-height: 1.5; }
.log-card h3 a:hover { color: var(--blue); }
.log-card .excerpt { color: var(--ink-2); font-size: 14px; flex: 1; }
.log-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-3);
  padding-top: 4px;
}
.log-foot .more { color: var(--blue); font-weight: 600; }
.log-card:hover .log-foot .more { text-decoration: underline; }

.section-foot { margin-top: 36px; text-align: center; }

/* =========================================================
   Roadmap (今後の検証予定)
   ========================================================= */
.roadmap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px 28px;
  margin-top: 8px;
}
.road-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}
.road-item .rk {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--blue);
  background: var(--bg-tint);
  border: 1px solid #d6e3fb;
  border-radius: 6px;
  padding: 4px 9px;
  flex: none;
  white-space: nowrap;
}
.road-item h4 { font-size: 15.5px; margin-bottom: 3px; }
.road-item p { font-size: 13.5px; color: var(--ink-2); }

/* =========================================================
   note CTA
   ========================================================= */
.note-cta {
  background: linear-gradient(180deg, #173a86, #0f2a66);
  color: #fff;
  border-radius: 18px;
  padding: 48px 44px;
  display: grid;
  grid-template-columns: 1.4fr auto;
  align-items: center;
  gap: 30px;
  position: relative;
  overflow: hidden;
}
.note-cta::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(420px 200px at 90% 120%, rgba(94,160,255,.4), transparent 70%);
  pointer-events: none;
}
.note-cta .eyebrow { color: #9cc0ff; }
.note-cta .eyebrow::before { background: #9cc0ff; }
.note-cta h2 { font-size: clamp(22px, 3vw, 28px); margin: 14px 0 12px; color: #fff; }
.note-cta p { color: #c5d4f0; font-size: 15px; max-width: 40em; }
.note-cta .btn-note {
  background: #fff;
  color: #143377;
  padding: 14px 26px;
  font-size: 15px;
  position: relative;
  z-index: 1;
}
.note-cta .btn-note:hover { background: #eaf1ff; }

/* =========================================================
   Policy (運営ポリシー)
   ========================================================= */
.policy-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px 40px;
}
.policy-item {
  display: flex;
  gap: 14px;
  padding: 18px 0;
  border-top: 1px solid var(--line);
}
.policy-item .pn {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--blue);
  flex: none;
}
.policy-item h4 { font-size: 15.5px; margin-bottom: 4px; }
.policy-item p { font-size: 14px; color: var(--ink-2); }

/* =========================================================
   Footer
   ========================================================= */
.site-footer {
  background: #0f1115;
  color: #cfd5df;
  padding: 56px 0 30px;
}
.footer-top {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 36px;
  border-bottom: 1px solid #232732;
}
.footer-brand .brand-name { color: #fff; font-size: 17px; font-weight: 700; }
.footer-brand .logo-mark { background: var(--blue); }
.footer-brand p { color: #8b94a3; font-size: 13.5px; margin-top: 14px; max-width: 30em; }
.footer-col h5 {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: #6f7888;
  margin: 0 0 14px;
  font-weight: 500;
}
.footer-col ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 9px; }
.footer-col a { font-size: 14px; color: #cfd5df; }
.footer-col a:hover { color: #fff; }
.footer-tags { display: flex; flex-wrap: wrap; gap: 7px; }
.footer-tags .t {
  font-family: var(--mono);
  font-size: 11px;
  color: #aeb6c4;
  border: 1px solid #2b313d;
  padding: 3px 9px;
  border-radius: 5px;
}
.footer-tags .t:hover { color: #fff; border-color: var(--blue); }
.footer-bottom {
  padding-top: 26px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 12.5px;
  color: #7b8494;
}
.disclaimer {
  max-width: 60em;
  font-size: 12.5px;
  color: #6f7888;
  line-height: 1.7;
}
.disclaimer strong { color: #9aa3b2; font-weight: 600; }

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .hero-visual { max-width: 480px; }
  .about-grid { grid-template-columns: 1fr; }
  .cat-grid { grid-template-columns: 1fr 1fr; }
  .log-list { grid-template-columns: 1fr; }
  .roadmap { grid-template-columns: 1fr; }
  .policy-grid { grid-template-columns: 1fr; }
  .note-cta { grid-template-columns: 1fr; padding: 36px 28px; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  body { font-size: 15.5px; }
  .nav { display: none; }
  .nav.open {
    display: flex;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 8px 0;
    box-shadow: 0 16px 30px -20px rgba(0,0,0,.3);
  }
  .nav.open a { padding: 12px 24px; }
  .nav.open > .btn { display: inline-flex; margin: 8px 24px; justify-content: center; }
  .nav-toggle {
    display: inline-grid;
    place-items: center;
    width: 40px; height: 40px;
    border: 1px solid var(--line-2);
    border-radius: 8px;
    background: #fff;
    cursor: pointer;
  }
  .nav-toggle svg { width: 20px; height: 20px; }
  .header-cta { display: none; }
  .hero { padding: 56px 0 52px; }
  .section { padding: 56px 0; }
  .cat-grid { grid-template-columns: 1fr; }
  .footer-top { grid-template-columns: 1fr; gap: 30px; }
  .note-cta { padding: 30px 22px; }
  .wrap { padding: 0 18px; }
}