/* ═══════════════════════════════════════════════════════════════════
   Signal — the shared design system.

   Everything here is scoped to .sg, so a page opts in by putting the class on
   its wrapper; nothing leaks into the rest of the site, which still runs on
   Tailwind. Extracted from the About page, which was the first page built in
   this language and remains its reference implementation.

   Display: Syne · Body: Inter · Labels: JetBrains Mono
   The three fonts are the page's responsibility to load.

   Contents
     Foundation     tokens, reset, shell, section rhythm, headings
     Accents        [data-accent] sets --accent / --accent-rgb per subtree
     Reveal         scroll-in animation, opt-in via [data-reveal]
     Buttons        .sg-btn and friends
     Bento          .sg-bento grid + .sg-card family
     Filters        pill row for filtering a collection
     Tiles          .sg-tile card with a screenshot or logo head
     Rails          infinite marquee of logos (.sg-brand / .sg-tech)
     Light section  .sg-notes inverts the tokens for one pale section
     Responsive     the breakpoints for the above, then reduced motion
   ═══════════════════════════════════════════════════════════════════ */


/* ═══════════════════════════════════════════════════════════════════
   Foundation
   ═══════════════════════════════════════════════════════════════════ */
.sg {
  --bg: #04070c; --bg-2: #070c14; --panel: #0a1119; --panel-2: #0e1722;
  --ink: #eef7f3; --muted: #9db3ac; --dim: #5f7772;
  --line: rgba(148, 163, 184, .13); --line-2: rgba(148, 163, 184, .24);
  --green: #34d399; --green-2: #6ee7b7; --cyan: #67e8f9; --warm: #f5c451;
  --display: 'Syne', 'Inter', system-ui, sans-serif;
  --body: 'Inter', system-ui, -apple-system, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --r: 1.25rem;
  position: relative; background: var(--bg); color: var(--ink); font-family: var(--body); overflow-x: clip;
  --accent: var(--green); --accent-rgb: 52, 211, 153;
}
.sg *, .sg *::before, .sg *::after { box-sizing: border-box; }
.sg-sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.sg-shell { width: min(1280px, calc(100% - 48px)); margin-inline: auto; }
.sg-section { position: relative; padding-block: clamp(5rem, 9vw, 8rem); }
.sg h1, .sg h2, .sg h3 { margin: 0; font-family: var(--display); letter-spacing: -.02em; line-height: 1.02; color: var(--ink); }
.sg h2 { font-size: clamp(2.2rem, 4.6vw, 4rem); font-weight: 800; text-wrap: balance; }
.sg h3 { font-size: clamp(1.4rem, 2.4vw, 2rem); font-weight: 700; }
.sg p { margin: 0; }
.sg-label { margin: 0 0 1rem; color: var(--green); font: 600 .68rem/1 var(--mono); letter-spacing: .24em; text-transform: uppercase; }
.sg-head { margin-bottom: clamp(2.5rem, 5vw, 4rem); }
.sg-head-sub { max-width: 44rem; margin-top: 1.1rem; color: var(--muted); font-size: 1.05rem; line-height: 1.65; }
.sg-head-split { display: flex; flex-wrap: wrap; gap: 1.5rem 3rem; align-items: flex-end; justify-content: space-between; }

/* ═══════════════════════════════════════════════════════════════════
   Accents
   ═══════════════════════════════════════════════════════════════════ */
[data-accent="emerald"] { --accent: #34d399; --accent-rgb: 52, 211, 153; }
[data-accent="cyan"] { --accent: #67e8f9; --accent-rgb: 103, 232, 249; }
[data-accent="violet"] { --accent: #c4b5fd; --accent-rgb: 196, 181, 253; }
[data-accent="amber"] { --accent: #fcd34d; --accent-rgb: 252, 211, 77; }
[data-accent="red"] { --accent: #fb7185; --accent-rgb: 251, 113, 133; }

/* ═══════════════════════════════════════════════════════════════════
   Reveal
   ═══════════════════════════════════════════════════════════════════ */
.sg.is-enhanced [data-reveal] { opacity: 0; transform: translateY(22px); transition: opacity .7s cubic-bezier(.2, .7, .2, 1), transform .7s cubic-bezier(.2, .7, .2, 1); }
.sg.is-enhanced [data-reveal].is-in { opacity: 1; transform: none; }

/* ═══════════════════════════════════════════════════════════════════
   Buttons
   ═══════════════════════════════════════════════════════════════════ */
.sg-btn { display: inline-flex; align-items: center; gap: .6rem; padding: .95rem 1.5rem; border-radius: 999px; font: 600 .9rem/1 var(--body); text-decoration: none; cursor: pointer; border: 1px solid var(--line-2); color: var(--ink); background: rgba(255, 255, 255, .03); transition: transform .2s, border-color .2s, background .2s, color .2s; position: relative; }
.sg-btn:hover { transform: translateY(-2px); border-color: rgba(var(--accent-rgb), .6); }
.sg-btn-primary { background: var(--green); border-color: var(--green); color: #04110c; }
.sg-btn-primary:hover { background: var(--green-2); }
.sg-actions { display: flex; flex-wrap: wrap; gap: .8rem; }
.sg-btn-pulse { position: absolute; inset: -4px; border-radius: inherit; border: 1px solid rgba(52, 211, 153, .5); animation: sg-pulse 2.4s ease-out infinite; pointer-events: none; }
@keyframes sg-pulse { 0% { transform: scale(1); opacity: .9; } 100% { transform: scale(1.18); opacity: 0; } }

/* ═══════════════════════════════════════════════════════════════════
   Bento cards
   ═══════════════════════════════════════════════════════════════════ */
.sg-bento { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); grid-auto-rows: minmax(150px, auto); gap: 1rem; }
.sg-card { --mx: 50%; --my: 50%; position: relative; grid-column: span 2; padding: 1.4rem 1.5rem; border-radius: var(--r); border: 1px solid var(--line); background: var(--panel); overflow: hidden; display: flex; flex-direction: column; gap: .5rem; transition: border-color .25s, transform .25s; }
.sg-card::before { content: ''; position: absolute; inset: 0; background: radial-gradient(420px circle at var(--mx) var(--my), rgba(52, 211, 153, .12), transparent 45%); opacity: 0; transition: opacity .3s; pointer-events: none; }
.sg-card:hover { border-color: var(--line-2); transform: translateY(-3px); }
.sg-card:hover::before { opacity: 1; }
.sg-card-wide { grid-column: span 4; }
.sg-card-tall { grid-row: span 2; }
.sg-card-num { grid-column: span 1; }
.sg-card-num .sg-card-huge { font-size: clamp(2.4rem, 4.2vw, 3.6rem); }
.sg-card-cta { grid-column: span 2; background: linear-gradient(150deg, rgba(52, 211, 153, .16), var(--panel) 60%); }
.sg-card-label { color: var(--green); font: 600 .62rem/1 var(--mono); letter-spacing: .22em; text-transform: uppercase; }
.sg-card-big { font-family: var(--display); font-size: clamp(1.5rem, 2.6vw, 2.2rem); font-weight: 800; letter-spacing: -.02em; color: #fff; }
.sg-card-big small { font: 600 .68rem/1 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--muted); }
.sg-card-huge { font-family: var(--display); font-size: clamp(3rem, 6vw, 5rem); font-weight: 800; line-height: .9; letter-spacing: -.04em; color: #fff; margin-top: auto; }
.sg-card-huge span { color: var(--green); }
.sg-card-sub { color: var(--muted); font-size: .9rem; }
.sg-card-and { color: var(--green); font-weight: 400; }
.sg-card-and { color: var(--green); font-weight: 400; }
.sg-card-text { color: var(--ink); font-size: 1.05rem; line-height: 1.55; margin-top: .2rem; }
.sg-live-list { list-style: none; margin: .4rem 0 0; padding: 0; display: grid; gap: .8rem; }
.sg-live-list b { display: block; font-family: var(--display); font-size: 2rem; font-weight: 800; line-height: 1; color: #fff; }
.sg-live-list span { color: var(--muted); font-size: .85rem; }
.sg-card-link { margin-top: auto; color: var(--green-2); font-size: .85rem; text-decoration: none; }
.sg-card-link:hover { text-decoration: underline; text-underline-offset: 3px; }
.sg-tags { display: flex; flex-wrap: wrap; gap: .4rem; list-style: none; margin: .3rem 0 0; padding: 0; }
.sg-tags > * { padding: .4rem .7rem; border-radius: 999px; border: 1px solid var(--line); color: var(--muted); font: 500 .76rem/1 var(--body); }
.sg-card-cta .sg-btn { align-self: flex-start; margin-top: auto; }

/* ═══════════════════════════════════════════════════════════════════
   Filters
   ═══════════════════════════════════════════════════════════════════ */
.sg-filters { display: flex; flex-wrap: wrap; gap: .4rem; }
.sg-filters button { padding: .5rem .85rem; border-radius: 999px; border: 1px solid var(--line-2); background: transparent; color: var(--muted); font: 600 .66rem/1 var(--mono); letter-spacing: .12em; text-transform: uppercase; cursor: pointer; }
.sg-filters button span { color: var(--dim); margin-left: .3rem; }
.sg-filters button.is-active { color: var(--green); border-color: rgba(52, 211, 153, .5); background: rgba(52, 211, 153, .08); }

/* ═══════════════════════════════════════════════════════════════════
   Tiles
   ═══════════════════════════════════════════════════════════════════ */
.sg-tile { display: flex; flex-direction: column; border-radius: var(--r); border: 1px solid var(--line); background: var(--panel); overflow: hidden; transition: transform .25s, border-color .25s; }
.sg-tile:hover { transform: translateY(-4px); border-color: rgba(var(--accent-rgb), .5); }
.sg-tile[hidden] { display: none; }
.sg-tile-screen { aspect-ratio: 16 / 9; background: #0b1220; overflow: hidden; border-bottom: 1px solid var(--line); }
.sg-tile-screen > img { width: 100%; height: 100%; object-fit: cover; object-position: top; transition: transform .6s; }
.sg-tile:hover .sg-tile-screen > img { transform: scale(1.04); }
.sg-tile-logo { width: 100%; height: 100%; display: grid; place-items: center; padding: 2rem; background: radial-gradient(circle at 50% 50%, rgba(var(--accent-rgb), .14), transparent 65%); }
.sg-tile-logo img { max-width: 150px; max-height: 56px; object-fit: contain; }
.sg-tile-logo strong { font-family: var(--display); font-size: 1.4rem; }
.sg-tile-body { padding: 1.2rem 1.3rem 1.4rem; display: grid; gap: .55rem; }
.sg-tile-meta { display: flex; justify-content: space-between; color: var(--dim); font: 600 .58rem/1 var(--mono); letter-spacing: .2em; text-transform: uppercase; }
.sg-tile-meta span:last-child { color: var(--green); }
.sg-tile h3 { font-size: 1.35rem; }
.sg-tile-tagline { color: var(--ink); font-size: .92rem; line-height: 1.5; }
.sg-tile-rel { color: var(--muted); font-size: .85rem; line-height: 1.55; }
.sg-tile-rel b { color: var(--ink); font-weight: 600; }
.sg-tile-links { display: flex; gap: 1rem; margin-top: .3rem; }
.sg-tile-links a { color: var(--green-2); font-size: .82rem; text-decoration: none; }
.sg-tile-links a:hover { text-decoration: underline; text-underline-offset: 3px; }

/* ═══════════════════════════════════════════════════════════════════
   Rails
   ═══════════════════════════════════════════════════════════════════ */
.sg-rails { display: grid; gap: 0; border-block: 1px solid var(--line); background: linear-gradient(90deg, rgba(52, 211, 153, .04), transparent 30%, transparent 70%, rgba(52, 211, 153, .04)); mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent); }
.sg-rail { overflow: hidden; }
.sg-rail + .sg-rail { border-top: 1px solid var(--line); }
.sg-rail-track { display: flex; width: max-content; animation: sg-rail var(--wall-speed, 46s) linear infinite; }
.sg-rail-b .sg-rail-track { animation-direction: reverse; animation-duration: calc(var(--wall-speed, 46s) * 2.1); }
.sg-rails.is-paused .sg-rail-track, .sg-rails:hover .sg-rail-track, .sg-rails:focus-within .sg-rail-track, .sg-rails.is-hidden .sg-rail-track { animation-play-state: paused; }
@keyframes sg-rail { to { transform: translateX(-50%); } }
.sg-rail-group { display: flex; flex: none; }
.sg-brand { position: relative; display: grid; place-items: center; width: 250px; height: 132px; padding: 1.4rem 2rem; border-right: 1px solid var(--line); text-decoration: none; color: inherit; transition: background .25s; }
.sg-brand img { display: block; max-width: 150px; max-height: 46px; width: auto; height: auto; object-fit: contain; opacity: .78; transition: opacity .25s, transform .25s; }
.sg-brand-mono { font: 800 1.1rem/1 var(--display); color: #fff; opacity: .8; }
.sg-brand:hover, .sg-brand:focus-visible { background: rgba(255, 255, 255, .03); }
.sg-brand:hover img, .sg-brand:focus-visible img { opacity: 1; transform: translateY(-6px); }
.sg-brand-label { position: absolute; left: 0; right: 0; bottom: .8rem; display: grid; text-align: center; opacity: 0; transform: translateY(6px); transition: opacity .25s, transform .25s; pointer-events: none; }
.sg-brand:hover .sg-brand-label, .sg-brand:focus-visible .sg-brand-label { opacity: 1; transform: none; }
.sg-brand-label b { color: var(--ink); font-size: .78rem; font-weight: 600; }
.sg-brand-label small { color: var(--green); font: 600 .58rem/1.4 var(--mono); letter-spacing: .16em; text-transform: uppercase; }
.sg-tech { width: 150px; height: 112px; }
.sg-tech img { max-width: 40px; max-height: 40px; opacity: .62; transition: opacity .25s, transform .25s, filter .25s; }
.sg-tech:hover img, .sg-tech:focus-visible img { opacity: 1; transform: translateY(-6px) scale(1.04); }
.sg-tech .sg-brand-label { bottom: .55rem; }
.sg-tech .sg-brand-label b { font-size: .7rem; }
.sg-tech .sg-brand-label small { font-size: .52rem; letter-spacing: .1em; }

/* ═══════════════════════════════════════════════════════════════════
   Light section
   ═══════════════════════════════════════════════════════════════════ */
.sg-notes { --ink: #12231c; --muted: #46615a; --dim: #7a8f88; --line: rgba(20, 60, 45, .16); --line-2: rgba(20, 60, 45, .3); color: var(--ink); background: #ece7db; background-image: linear-gradient(rgba(97, 79, 48, .06) 1px, transparent 1px); background-size: 100% 38px; }
.sg-notes h2, .sg-notes h3 { color: var(--ink); }
.sg-notes .sg-label { color: #8b6636; }

/* ═══════════════════════════════════════════════════════════════════
   Utilities
   ═══════════════════════════════════════════════════════════════════ */
.sg-empty { color: var(--dim); font-style: italic; }

/* ═══════════════════════════════════════════════════════════════════
   Responsive
   ═══════════════════════════════════════════════════════════════════ */
@media (max-width: 1100px) {
  .sg-bento { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .sg-card-wide { grid-column: span 4; }
}
@media (max-width: 640px) {
  .sg-shell { width: calc(100% - 32px); }
  .sg-bento { grid-template-columns: repeat(2, minmax(0, 1fr)); grid-auto-rows: auto; }
  .sg-card, .sg-card-wide, .sg-card-cta { grid-column: span 2; }
  .sg-card-num { grid-column: span 1; }
  .sg-card-tall { grid-row: auto; }
  .sg-brand { width: 200px; height: 112px; }
  .sg-tech { width: 128px; height: 96px; }
}
@media (prefers-reduced-motion: reduce) {
  .sg *, .sg *::before, .sg *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .sg.is-enhanced [data-reveal] { opacity: 1; transform: none; }
  .sg-rail-track { animation: none !important; }
  .sg-rails { mask-image: none; }
  .sg-rail { overflow-x: auto; }
}