/*
 * KaraokeMachine — the landing page.
 *
 * The palette is the machine's own, from `crates/playback/km-display/src/theme.rs`, so the page is
 * framed in the colors its screenshots were drawn in. Amber is `lyric_sung` — the color a syllable
 * turns as it is sung — and it is also the machine's icon color; blue and green are the package
 * builder's and the remote's, which is why the cards for those two are not amber.
 *
 * Dark is committed to rather than toggled. The product is a full-screen television application,
 * every screenshot is dark, and a light variant would frame all eight of them badly.
 *
 * The *surfaces* are the icons' ground rather than a neutral gray — `icon_ground` and `icon_glow`,
 * the violet-into-magenta the three marks stand on. `--bg` is still `theme.background`, because the
 * page's ground and the television's are answering the same question; what changed is everything
 * lifted off it. The reason is the same one that lifted the icons: eight dark screenshots on a
 * near-black page make a black rectangle with pictures in it, and the frame is the only part of a
 * landing page that is allowed to have a color of its own. `--raised`, `--line`, `--dim` and
 * `--muted` are page-only and have no theme source, so they are re-derived toward the violet rather
 * than copied from anywhere.
 *
 * No webfont, no script, no external request of any kind.
 */

:root {
  color-scheme: dark;

  --bg:      #0A0C14;   /* theme.background   */
  --ground:  #2A0E42;   /* theme.icon_ground  — the icons' own ground */
  --glow:    #C43A8E;   /* theme.icon_glow    */
  --raised:  #2A1B44;   /* derived from --ground, page-only */
  --line:    #3A2757;   /* derived from --ground, page-only */
  --text:    #ECEFF4;   /* theme.text         */
  --dim:     #9A92AA;   /* theme.text_dim, warmed onto --ground */
  --muted:   #B3A9C2;   /* theme.lyric_upcoming, likewise */
  --amber:   #FFC107;   /* theme.lyric_sung   — the machine */
  --blue:    #5FD3FF;   /* theme.accent       — km-package-builder */
  --green:   #57E79A;   /* theme.accent_alt   — km-remote */

  --wrap: 68rem;
  --radius: 10px;

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial,
          "Noto Sans", sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.65;
  /* The hero image is full-bleed; nothing else may push the page sideways. */
  overflow-x: hidden;
}

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

code, .mono { font-family: var(--mono); font-size: 0.92em; }

code {
  background: var(--raised);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 0.1em 0.35em;
}

pre {
  background: var(--ground);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.9rem 1.1rem;
  overflow-x: auto;
}

pre code { background: none; border: 0; padding: 0; }

a { color: var(--amber); text-decoration-color: rgba(255, 193, 7, 0.4); text-underline-offset: 3px; }
a:hover { text-decoration-color: var(--amber); }

.wrap { max-width: var(--wrap); margin-inline: auto; padding-inline: 1.5rem; }

.skip {
  position: absolute;
  left: -9999px;
}
.skip:focus {
  left: 1rem; top: 1rem;
  position: fixed; z-index: 10;
  background: var(--amber); color: #000;
  padding: 0.6rem 1rem; border-radius: 6px;
  text-decoration: none; font-weight: 600;
}

:focus-visible { outline: 2px solid var(--amber); outline-offset: 3px; }

/* -- hero ------------------------------------------------------------------------------------- */

.hero {
  padding-top: 4.5rem;
  text-align: center;
  /* Two pools of light, and the order matters. The magenta is the icons' own glow, thrown wide and
     off-center the way `icon.rs` throws it — its wash center is at 32% across, not the middle. The
     amber sits on top of it, tighter and directly behind the title, so the word the eye lands on is
     still lit the color of a sung syllable. One gradient of either alone read as decoration; the
     pair reads as a stage. */
  background:
    radial-gradient(52rem 26rem at 50% -4rem, rgba(255, 193, 7, 0.12), transparent 68%),
    radial-gradient(88rem 40rem at 32% -10rem, rgba(196, 58, 142, 0.30), transparent 72%),
    var(--bg);
}

/* The other language, above a hero that is otherwise centered. It sits right and quiet: a reader who
   wants it is looking for it, and a reader who does not is looking at the title. */
.lang {
  margin: 0 0 1.4rem;
  text-align: right;
  font-size: 0.85rem;
}
.lang a {
  color: var(--dim);
  text-decoration-color: rgba(154, 146, 170, 0.4);
}
.lang a:hover { color: var(--text); text-decoration-color: currentColor; }

.eyebrow {
  margin: 0 0 1.1rem;
  color: var(--dim);
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.hero h1 {
  margin: 0;
  font-size: clamp(2.6rem, 8vw, 4.6rem);
  line-height: 1.05;
  letter-spacing: -0.03em;
  font-weight: 800;
}
.hero h1 span { color: var(--amber); }
/* `inline-block` undoes the global `img { display: block }`, which would give the mark a line of
   its own. The width tracks the h1's clamp; height stays auto, so the attributes set the ratio. */
.hero h1 .mark {
  display: inline-block;
  width: clamp(2.2rem, 6.5vw, 3.6rem);
  vertical-align: -0.12em;
  margin-right: 0.5rem;
}

.lede {
  max-width: 46rem;
  margin: 1.4rem auto 0;
  font-size: clamp(1.02rem, 2.2vw, 1.2rem);
  color: var(--muted);
}
.lede strong { color: var(--text); font-weight: 600; }

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin: 2rem 0 0;
}

.btn {
  display: inline-block;
  padding: 0.7rem 1.5rem;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--raised);
  color: var(--text);
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}
.btn:hover { transform: translateY(-1px); border-color: var(--muted); }

.btn-primary {
  background: var(--amber);
  border-color: var(--amber);
  color: #14100A;
}
.btn-primary:hover { background: #FFCE3A; border-color: #FFCE3A; }

.honesty {
  margin: 1.6rem auto 0;
  max-width: 40rem;
  font-size: 0.9rem;
  color: var(--dim);
}

/* -- screenshots ------------------------------------------------------------------------------ */

.shot { margin: 0; }

.shot img {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #000;
}

.shot figcaption {
  margin-top: 0.7rem;
  font-size: 0.87rem;
  line-height: 1.5;
  color: var(--dim);
}
.shot figcaption b { color: var(--muted); }

.shot-hero {
  max-width: 60rem;
  margin: 3.2rem auto 0;
  padding-inline: 1.5rem;
}
.shot-hero img {
  border-radius: 12px 12px 0 0;
  border-bottom: 0;
  box-shadow: 0 -2px 60px rgba(196, 58, 142, 0.22);
}

/* The phone captures are tall; cap them so a row of four does not become a wall. */
.shot-phone img { max-height: 34rem; width: auto; margin-inline: auto; }

.shot-wide { margin-top: 3rem; }

/* The animated playing screen sits under the two television stills, a gallery gap below them. */
.shot-singing { margin-top: 1.8rem; }

/* km-package-builder's is a dense table of small text. Scaled to fit a phone it is a gray smear, so
   below its natural width it becomes pannable inside its own figure instead — the reader drags it,
   which is what you do with a wide table on a phone anyway. `.table-scroll` does the same for the
   carrier table. Nothing else on the page may scroll sideways. */
.shot-wide { overflow-x: auto; }
.shot-wide img { min-width: 44rem; }

.gallery { display: grid; gap: 1.8rem; margin-top: 1.5rem; }

/* Two 16:9 television shots. They stack on a phone: half of 390px is unreadable for a whole screen
   of words. The floor is `min(22rem, 100%)` and not a bare 22rem, because a phone narrower than
   400px has less than 22rem of content, and a bare floor pushes the single track off the right edge,
   where `body`'s `overflow-x` clips it. `.cards` and `.foot-grid` take the same form. */
.gallery-2 { grid-template-columns: repeat(auto-fit, minmax(min(22rem, 100%), 1fr)); }

/* Four tall phone shots. `auto-fit` takes these to 4, then 2 — and it must NOT reach 1: a phone
   screenshot shown at full phone width is life-size, and four of them at life size is four screens
   of scrolling to look at a gallery. Two-up keeps it a strip you glance at, which is the job.
   Hence a floor of two columns rather than `minmax`'s natural collapse. */
/* 14rem and not 15: the container is 65rem of content, and four 15rem tracks plus three 1.8rem gaps
   is 65.4 — which overflows by a quarter of a rem and silently drops the row to three, leaving the
   fourth shot alone underneath. Measured, not guessed. */
.gallery-4 { grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr)); }

@media (max-width: 34rem) {
  .gallery-4 { grid-template-columns: repeat(2, 1fr); gap: 1rem; }
  .gallery-4 .shot figcaption { font-size: 0.8rem; }
}

.gallery-title {
  margin: 3rem 0 0;
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--dim);
}

/* -- sections --------------------------------------------------------------------------------- */

main section { padding: 4.5rem 0 1rem; }

h2 {
  margin: 0 0 1.6rem;
  font-size: clamp(1.6rem, 4vw, 2.1rem);
  letter-spacing: -0.02em;
  line-height: 1.2;
}

/* Full-bleed, so it takes an inner `<div class="wrap">` the way `.hero` and `footer` do -- never
   `class="wrap band"` on the section itself. That spelling clipped the tint to 68rem, which read as
   a box rather than a band, and this shorthand's `0` then beat `.wrap`'s `padding-inline` at equal
   specificity and sat the text on the edge. `border-block` is the tell: a box would want four
   sides. */
.band {
  margin-top: 3rem;
  padding: 3rem 0 3.2rem;
  background: var(--ground);
  border-block: 1px solid var(--line);
}
.band p { max-width: 44rem; color: var(--muted); }
.band .mono { color: var(--amber); }
/* km-admin's hue, the fourth of the four. `--glow` straight measures 3.50:1 on `--ground` against
   about 10:1 for the other three, so it is lifted 18% toward white -- the same answer `icon.rs`
   gives, at a bigger number because the icon's M stands on the near-black plate and this stands on
   the violet. 4.64:1. Lifted here rather than in `--glow`, which the hero's wash still wants dark. */
.band-admin h2 { color: #CF5DA2; }

.prose { max-width: 46rem; color: var(--muted); }
.prose b { color: var(--text); }
.dim { color: var(--dim); }

/* -- feature cards ---------------------------------------------------------------------------- */

/* Two by two, and the floor is what forces it. There are exactly four cards, so a three-across row
   leaves the fourth stranded beside an empty half of the page — which is what a 20rem floor does in
   a 65rem container. 22rem admits two tracks and never three. */
.cards {
  display: grid;
  gap: 1.4rem;
  grid-template-columns: repeat(auto-fit, minmax(min(22rem, 100%), 1fr));
}

.card {
  background: var(--ground);
  border: 1px solid var(--line);
  border-top: 2px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem 1.7rem;
}

/* The three product colors, used as the products use them. */
.card-amber { border-top-color: var(--amber); }
.card-blue  { border-top-color: var(--blue); }
.card-green { border-top-color: var(--green); }

.card h3 { margin: 0 0 0.9rem; font-size: 1.15rem; }
.card-amber h3 { color: var(--amber); }
.card-blue  h3 { color: var(--blue); }
.card-green h3 { color: var(--green); }

.card ul { margin: 0; padding-left: 1.15rem; }
.card li { margin-bottom: 0.75rem; color: var(--muted); font-size: 0.95rem; }
.card li:last-child { margin-bottom: 0; }
.card li b { color: var(--text); }

/* -- the carrier table ------------------------------------------------------------------------ */

.table-scroll { overflow-x: auto; margin-top: 1.8rem; }

.carriers {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.carriers th, .carriers td {
  padding: 1rem 1.1rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.carriers thead th {
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--dim);
  border-bottom-color: var(--muted);
}

.carriers tbody th {
  color: var(--amber);
  white-space: nowrap;
  width: 12rem;
}

.carriers td { color: var(--muted); }
.carriers td b { color: var(--text); }

/* -- footer ----------------------------------------------------------------------------------- */

footer {
  margin-top: 4rem;
  padding: 3rem 0 4rem;
  border-top: 1px solid var(--line);
  background: var(--ground);
  font-size: 0.92rem;
}

.foot-grid {
  display: grid;
  gap: 2.5rem;
  grid-template-columns: repeat(auto-fit, minmax(min(18rem, 100%), 1fr));
}

footer h3 { margin: 0 0 0.8rem; font-size: 1rem; color: var(--text); }
footer ul { margin: 0; padding: 0; list-style: none; }
footer li { margin-bottom: 0.5rem; color: var(--dim); }
footer p { margin: 0 0 0.8rem; }

.foot-author {
  margin: 2.5rem 0 0;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
}

/* -- narrow ------------------------------------------------------------------------------------ */

@media (max-width: 40rem) {
  body { font-size: 16px; }
  .hero { padding-top: 3rem; }
  main section { padding-top: 3.2rem; }
  .shot-hero { padding-inline: 1rem; }
  .card { padding: 1.3rem 1.3rem; }

  /* `KaraokeMachine` is one word and cannot wrap. At the h1's desktop floor it is wider than a
     320px phone, so the floor drops here and the size follows the viewport. */
  .hero h1 { font-size: clamp(2rem, 10.5vw, 2.6rem); }
  .hero h1 .mark { width: clamp(1.7rem, 8.5vw, 2.2rem); margin-right: 0.35rem; }

  /* The carrier table stops being a table: two columns of prose in 390px is unreadable, and
     scrolling a table sideways is worse than stacking it. */
  .carriers, .carriers tbody, .carriers tr, .carriers td, .carriers th { display: block; }
  .carriers thead { position: absolute; left: -9999px; }
  .carriers tr {
    border: 1px solid var(--line);
    border-radius: var(--radius);
    margin-bottom: 1rem;
    padding: 0.4rem 0.9rem 0.9rem;
    background: var(--ground);
  }
  /* The card carries the inset, so a cell carries none: both at once indent the words twice. */
  .carriers tbody th { width: auto; border-bottom: 0; padding: 0.5rem 0 0.2rem; }
  .carriers td { border-bottom: 0; padding: 0.2rem 0 0; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
  .btn:hover { transform: none; }
}