/* SIGNify — Apple-style interface foundations.
 *
 * Structured as tokens first, then chrome, layout, controls, surfaces, and
 * finally the accessibility overrides. Every selector the page scripts rely on
 * (.stage, .stage.live, .sign-*, .toggle[aria-pressed], .status[data-state],
 * .audio-viz.live with --level/--gain, .committed/.partial/.placeholder, .field,
 * .slider) is preserved, so no JavaScript changes with this stylesheet.
 */

/* ---- tokens --------------------------------------------------------------
   Surfaces form an elevation ladder: --bg sits furthest back, --surface holds
   cards, --surface-raised is the step above it, and --chrome is the floating
   translucent layer content scrolls beneath. */
/* Palette sampled from the reference design: pale icy background (#d4e4e4),
   white cards, dusty blue (#aecfd4 with #708d9a as its deep tone), and blush
   (#e9d8d2). Each accent is a PAIR — a pastel for fills and a deep tone for
   anything small or text-bearing — because pastel fills cannot carry text at
   4.5:1. Light is the default here; dark derives from the same hues below. */
:root {
  color-scheme: light dark;

  --bg-top: #ecd6ce;
  --bg-bottom: #c5d8dc;
  --bg: linear-gradient(180deg, var(--bg-top) 0%, var(--bg-bottom) 100%);
  --surface: #ffffff;
  --surface-raised: #f4f8f9;
  /* The camera/mic stage is a container, not content, so it stays distinct from
     the white transcript panel beside it rather than merging into one surface. */
  --stage: #dce8ea;
  --header: #ecd6ce;
  --chrome: rgba(236, 214, 206, 0.62);
  /* The bright edge where light catches the top of a translucent material. */
  --chrome-edge: rgba(255, 255, 255, 0.9);

  --text: #1f2e34;
  --muted: rgba(31, 46, 52, 0.62);
  --line: rgba(79, 110, 123, 0.18);
  --tint: rgba(79, 110, 123, 0.08);
  --tint-strong: rgba(79, 110, 123, 0.14);
  /* Controls need more presence than a hover tint, so they get their own
     values rather than borrowing --tint-strong. */
  --track: rgba(79, 110, 123, 0.22);
  --tick: rgba(79, 110, 123, 0.34);
  /* Fades to the same colour at zero alpha. Fading to `transparent` interpolates
     through transparent black in sRGB, which shows up as a grey band. */
  --sheen: linear-gradient(
    180deg,
    rgba(255, 255, 255, 0.55),
    rgba(255, 255, 255, 0) 58%
  );

  /* Blue: navigation and selection. */
  --accent-fill: #aecfd4;
  --on-accent: #17323b;
  --accent: #4f6e7b;
  /* Blush: interactive chrome and live capture. Dusty blue stays on the
     current-page nav so the two colours still mean different things. */
  --live-fill: #e9d8d2;
  --on-live: #3d2721;
  /* Deeper than the reference's blush: the dot and the mic bars are thin
     graphics, and pastel on white would not clear 3:1. */
  --live: #a2604d;
  --blush-tint: rgba(162, 96, 77, 0.1);
  --blush-strong: rgba(162, 96, 77, 0.2);
  --blush-line: rgba(162, 96, 77, 0.28);
  --danger: #a8281d;

  --panel: #ffffff;
  --panel-text: #1f2e34;
  --panel-muted: rgba(31, 46, 52, 0.5);

  /* Soft, wide, and cool-tinted, as in the reference. Bigger surfaces read as
     thicker: a tight shadow for chips, a wide one for cards, the deepest for
     the stage. */
  --shadow-1: 0 1px 2px rgba(79, 110, 123, 0.12);
  --shadow-2:
    0 10px 28px rgba(79, 110, 123, 0.16),
    0 2px 6px rgba(79, 110, 123, 0.07);
  --shadow-3:
    0 26px 60px rgba(79, 110, 123, 0.2),
    0 4px 12px rgba(79, 110, 123, 0.1);
  --shadow: var(--shadow-2);

  --radius: 22px;
  --radius-sm: 14px;

  /* The platform font already ships optical sizing and tracking tables. */
  --font-text: -apple-system, BlinkMacSystemFont, "SF Pro Text",
    "Segoe UI Variable Text", "Segoe UI", system-ui, sans-serif;
  --font-display: "ADLaM Display", var(--font-text);

  /* Critically damped feel: fast out, settles without overshoot. --ease-in is
     its inverse, so a reversible transition returns along the same path. */
  --ease-out: cubic-bezier(0.32, 0.72, 0, 1);
  --ease-in: cubic-bezier(1, 0, 0.68, 0.28);
  --t-press: 100ms;
  --t-fast: 180ms;
  --t-base: 320ms;
}

/* Same hues, inverted lightness. The accents swap roles: the deep tone becomes
   the fill and the pastel becomes the text on it. theme.js writes data-theme
   before first paint; without JS the page stays on the light default. */
:root[data-theme="dark"] {
    --bg-top: #2c1d1a;
    --bg-bottom: #151f23;
    --bg: linear-gradient(180deg, var(--bg-top) 0%, var(--bg-bottom) 100%);
    --surface: #1e2c31;
    --surface-raised: #26373d;
    --stage: #223238;
    --header: #2c1d1a;
    --chrome: rgba(44, 29, 26, 0.68);
    --chrome-edge: rgba(255, 255, 255, 0.09);

    --text: #e6eef0;
    --muted: rgba(230, 238, 240, 0.62);
    --line: rgba(197, 217, 223, 0.16);
    --tint: rgba(197, 217, 223, 0.08);
    --tint-strong: rgba(197, 217, 223, 0.15);
    --track: rgba(197, 217, 223, 0.24);
    --tick: rgba(197, 217, 223, 0.34);
    --sheen: linear-gradient(
      180deg,
      rgba(197, 217, 223, 0.06),
      rgba(197, 217, 223, 0) 58%
    );

    --accent-fill: #4f6e7b;
    --on-accent: #f2f8f9;
    --accent: #a6c6ce;
    --live-fill: #8f5344;
    --on-live: #fbeee9;
    --live: #dda08c;
    --blush-tint: rgba(221, 160, 140, 0.12);
    --blush-strong: rgba(221, 160, 140, 0.22);
    --blush-line: rgba(221, 160, 140, 0.32);
    --danger: #f0a9a0;

    --panel: #ffffff;
    --panel-text: #1f2e34;
    --panel-muted: rgba(31, 46, 52, 0.5);

    --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.32);
    --shadow-2:
      0 10px 28px rgba(0, 0, 0, 0.34),
      0 2px 6px rgba(0, 0, 0, 0.2);
    --shadow-3:
      0 26px 60px rgba(0, 0, 0, 0.44),
      0 4px 12px rgba(0, 0, 0, 0.24);
}

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

html {
  height: 100%;
  background: var(--bg-bottom);
}

/* Ease the scheme change itself. data-theme-ready is set after first paint so
   the initial load does not animate from the default tokens. */
html[data-theme-ready],
html[data-theme-ready] body,
html[data-theme-ready] header,
html[data-theme-ready] .stage,
html[data-theme-ready] .genText,
html[data-theme-ready] .settings-card,
html[data-theme-ready] .toggle,
html[data-theme-ready] .menu a,
html[data-theme-ready] select {
  transition:
    background-color var(--t-base) var(--ease-out),
    color var(--t-base) var(--ease-out),
    border-color var(--t-base) var(--ease-out),
    box-shadow var(--t-base) var(--ease-out);
}

body {
  min-height: 100%;
  margin: 0;
  display: flex;
  flex-direction: column;
  background: var(--bg) fixed;
  color: var(--text);
  font-family: var(--font-text);
  font-size: 100%;
  font-weight: 400;
  line-height: 1.5;
  font-optical-sizing: auto;
  -webkit-font-smoothing: antialiased;
}

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

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

/* ---- chrome --------------------------------------------------------------
   The page wash is viewport-fixed, so a transparent header sits in the same
   gradient instead of frosting a separate material over it. */
header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: transparent;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: min(1180px, 94%);
  min-height: 68px;
  margin: 0 auto;
  padding: 0.75rem 0;
}

header h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 400;
  /* Large type reads too loose as it grows, so tracking goes negative. */
  letter-spacing: -0.01em;
  line-height: 1.1;
}

.menu ul {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.menu a {
  display: inline-block;
  padding: 0.5rem 0.95rem;
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: -0.003em;
  transition:
    background var(--t-fast) var(--ease-out),
    color var(--t-fast) var(--ease-out),
    transform var(--t-press) var(--ease-out);
}

@media (hover: hover) {
  .menu a:hover {
    color: var(--text);
    background: var(--tint);
  }
}

/* Feedback lives on the press, not the release. */
.menu a:active {
  transform: scale(0.96);
}

.menu a.active {
  color: var(--on-accent);
  background: var(--accent-fill);
  font-weight: 600;
  box-shadow: var(--shadow-1);
}

.menu a:focus-visible,
.toggle:focus-visible,
select:focus-visible,
input[type="range"]:focus-visible {
  outline: 2px solid var(--live);
  outline-offset: 2px;
}

/* ---- layout & type ------------------------------------------------------- */
main {
  flex: 1;
  width: min(1180px, 94%);
  margin: 0 auto;
  padding: 2.25rem 0 3.5rem;
}

h2 {
  margin: 0 0 0.3rem;
  font-size: clamp(2rem, 2.7vw, 2.5rem);
  font-weight: 700;
  /* Tight leading and negative tracking belong together at display sizes. */
  line-height: 1.07;
  letter-spacing: -0.022em;
}

h3 {
  margin: 0 0 1.25rem;
  font-size: 1.0625rem;
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: -0.004em;
  color: var(--muted);
}

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.section-head h3 {
  margin-bottom: 0;
}

/* ---- controls ------------------------------------------------------------ */
.toggle {
  padding: 0.5rem 1.15rem;
  background: var(--tint);
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text);
  font: inherit;
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: -0.003em;
  cursor: pointer;
  transition:
    background var(--t-fast) var(--ease-out),
    color var(--t-fast) var(--ease-out),
    border-color var(--t-fast) var(--ease-out),
    transform var(--t-press) var(--ease-out);
}

@media (hover: hover) {
  .toggle:hover {
    background: var(--tint-strong);
  }
}

.toggle:active {
  transform: scale(0.97);
}

.toggle[aria-pressed="true"] {
  background: var(--accent-fill);
  border-color: transparent;
  color: var(--on-accent);
  font-weight: 600;
  box-shadow: var(--shadow-1);
}

.toggle:disabled {
  opacity: 0.55;
  cursor: progress;
}

.controls {
  display: flex;
  align-items: center;
  gap: 0.9rem;
}

/* Small text over a translucent layer needs a little more weight and tracking
   than body copy, or it goes soft against a moving background. */
.status {
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.008em;
  color: var(--muted);
}

.status::before {
  content: "";
  display: inline-block;
  width: 0.5rem;
  height: 0.5rem;
  margin-right: 0.45rem;
  border-radius: 50%;
  background: currentColor;
  opacity: 0.5;
}

.status[data-state="live"] {
  color: var(--text);
  font-weight: 600;
}

.status[data-state="live"]::before {
  opacity: 1;
  background: var(--live);
  animation: status-pulse 1.6s ease-in-out infinite;
}

.status[data-state="error"] {
  color: var(--danger);
}

@keyframes status-pulse {
  0%,
  100% {
    opacity: 1;
  }

  50% {
    opacity: 0.25;
  }
}

.note {
  margin: -0.5rem 0 1.1rem;
  max-width: 68ch;
  font-size: 0.8125rem;
  font-weight: 500;
  line-height: 1.5;
  letter-spacing: 0.006em;
  color: var(--muted);
}

/* ---- workspace surfaces -------------------------------------------------- */
.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
  gap: 1.25rem;
  min-height: min(58vh, 520px);
}

.stage,
.genText,
.settings-card {
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-2);
}

.stage {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 360px;
  background: var(--sheen), var(--stage);
  color: var(--muted);
  font-size: 1.0625rem;
  letter-spacing: -0.004em;
}

.mic-input {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.15rem;
}

.audio-viz {
  display: flex;
  align-items: flex-end;
  gap: 0.45rem;
  height: 4.5rem;
}

.audio-viz span {
  width: 0.5rem;
  height: 100%;
  background: var(--live);
  opacity: 0.55;
  border-radius: 999px;
  transform-origin: bottom;
  animation: audio-bar 1.3s ease-in-out infinite;
}

.audio-viz span:nth-child(1) { animation-delay: -1.2s; --gain: 0.55; }
.audio-viz span:nth-child(2) { animation-delay: -0.5s; --gain: 0.72; }
.audio-viz span:nth-child(3) { animation-delay: -0.9s; --gain: 0.88; }
.audio-viz span:nth-child(4) { animation-delay: -0.2s; --gain: 1; }
.audio-viz span:nth-child(5) { animation-delay: -1s; --gain: 0.9; }
.audio-viz span:nth-child(6) { animation-delay: -0.4s; --gain: 0.7; }
.audio-viz span:nth-child(7) { animation-delay: -0.75s; --gain: 0.52; }

/* While a session is open the bars track the real mic level, so the idle
   keyframe loop has to get out of the way. */
.audio-viz.live span {
  animation: none;
  opacity: 1;
  background: var(--live);
  transform: scaleY(clamp(0.12, calc(var(--level, 0) * var(--gain, 1)), 1));
  transition: transform 90ms ease-out;
}

@keyframes audio-bar {
  0%,
  100% {
    transform: scaleY(0.22);
  }

  50% {
    transform: scaleY(1);
  }
}

/* A solid surface, deliberately: a light translucent layer over a light
   background destroys legibility. */
.genText {
  margin: 0;
  min-height: 360px;
  padding: 1.5rem 1.6rem;
  background: var(--panel);
  color: var(--panel-text);
  font-size: 1.1875rem;
  font-weight: 400;
  line-height: 1.5;
  letter-spacing: -0.01em;
  overflow-y: auto;
}

.placeholder {
  color: var(--panel-muted);
}

/* Interim text the model may still revise, set apart from committed text. */
.partial {
  color: var(--panel-muted);
}

.partial:not(:empty)::before {
  content: " ";
}

/* ---- settings ------------------------------------------------------------ */
.settings-grid {
  display: grid;
  gap: 1rem;
}

.settings-card {
  padding: 1.5rem 1.6rem;
  background: var(--surface);
  box-shadow:
    var(--shadow-2),
    inset 0 1px 0 var(--blush-line);
}

.settings-card h3 {
  margin-bottom: 0.85rem;
  color: var(--text);
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.field {
  display: grid;
  gap: 0.45rem;
  margin-top: 1.15rem;
  font-size: 0.9375rem;
  font-weight: 400;
  color: var(--muted);
}

.field:first-child {
  margin-top: 0;
}

.field span {
  color: var(--text);
  font-weight: 600;
  letter-spacing: -0.003em;
}

select,
input[type="range"] {
  width: 100%;
  font: inherit;
  color: var(--text);
}

select {
  padding: 0.65rem 0.8rem;
  background: var(--surface-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  cursor: pointer;
  transition:
    background var(--t-fast) var(--ease-out),
    border-color var(--t-fast) var(--ease-out),
    transform var(--t-press) var(--ease-out);
}

@media (hover: hover) {
  select:hover {
    border-color: var(--tint-strong);
  }
}

select:active {
  transform: scale(0.995);
}

/* Custom track and knob: the native control cannot carry the theme's colors
   in both schemes, and the knob is too small to grab confidently. */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  height: 1.5rem;
  margin: 0;
  background: transparent;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-runnable-track {
  height: 0.375rem;
  border-radius: 999px;
  background: var(--blush-strong);
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 1.25rem;
  height: 1.25rem;
  /* Centres the knob on a 0.375rem track. */
  margin-top: -0.4375rem;
  border: none;
  border-radius: 50%;
  background: var(--live);
  box-shadow: var(--shadow-1);
  transition: transform var(--t-press) var(--ease-out);
}

input[type="range"]::-moz-range-track {
  height: 0.375rem;
  border-radius: 999px;
  background: var(--blush-strong);
}

input[type="range"]::-moz-range-thumb {
  width: 1.25rem;
  height: 1.25rem;
  border: none;
  border-radius: 50%;
  background: var(--live);
  box-shadow: var(--shadow-1);
  transition: transform var(--t-press) var(--ease-out);
}

/* Grabbing the knob grows it toward the finger. */
input[type="range"]:active::-webkit-slider-thumb {
  transform: scale(1.15);
}

input[type="range"]:active::-moz-range-thumb {
  transform: scale(1.15);
}

.slider {
  display: grid;
  gap: 0.3rem;
}

.slider-ticks {
  display: flex;
  justify-content: space-between;
  /* Half the knob's width, so the end ticks line up with its travel limits. */
  padding: 0 0.625rem;
}

.slider-ticks span {
  width: 1px;
  height: 0.4rem;
  background: var(--blush-line);
}

/* .note's negative top margin tightens it under a page subhead. Here it sits
   below the last slider instead, where that pull lands on the tick marks. */
.settings-card .note {
  margin: 0.9rem 0 0;
}

.segmented {
  display: flex;
  padding: 0.2rem;
  background: var(--blush-tint);
  border: 1px solid var(--blush-line);
  border-radius: 999px;
}

.segment {
  flex: 1;
  min-width: 0;
  padding: 0.45rem 0.7rem;
  border: none;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: -0.003em;
  cursor: pointer;
  transition:
    background var(--t-fast) var(--ease-out),
    color var(--t-fast) var(--ease-out),
    transform var(--t-press) var(--ease-out);
}

.segment:active {
  transform: scale(0.97);
}

.segment[aria-checked="true"] {
  background: var(--surface);
  color: var(--text);
  font-weight: 600;
  box-shadow: var(--shadow-1);
}

.segment:focus-visible {
  outline: 2px solid var(--live);
  outline-offset: 2px;
}

/* ---- breakpoints --------------------------------------------------------- */
@media (min-width: 861px) {
  .field {
    grid-template-columns: minmax(0, 210px) minmax(0, 1fr);
    align-items: center;
    gap: 1.25rem;
  }
}

@media (max-width: 860px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
    padding: 0.9rem 0;
  }

  .menu ul {
    flex-wrap: wrap;
  }

  .workspace {
    grid-template-columns: 1fr;
    min-height: 0;
  }

  .stage,
  .genText {
    min-height: 240px;
  }
}

/* ---- sign page: live camera stage ---------------------------------------
   sign.js replaces the "Camera feed" placeholder inside .stage with a <video>
   and two status lines. .stage is a centred flex row by default, so it is
   restated as a column here; everything else is scoped to .sign-* so the
   mockup styling is untouched when the camera is off. */

.stage.sign-stage {
  /* The stage holds the camera and nothing else now, so it centres its one
     child both ways. .sign-status is the only other node and it collapses to
     display:none while empty, which keeps the video optically centred rather
     than pushed up by a reserved caption line. */
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0;
  padding: 0.9rem;
  overflow: hidden;
}

.sign-video {
  /* Fill the rounded box without distorting: cover crops to the box and
     object-position defaults to centre, so the signer stays in the middle
     whatever the camera's aspect ratio is. */
  width: 100%;
  height: 100%;
  flex: 1 1 auto;
  min-height: 0;
  align-self: center;
  border-radius: calc(var(--radius) - 8px);
  background: #000;
  object-fit: cover;
  /* MIRRORED FOR DISPLAY ONLY. sign.js draws the un-mirrored frame to its
     canvas; this flip never reaches the wire. Signing at a mirror image of
     yourself is what people expect. */
  transform: scaleX(-1);
}

.sign-status {
  margin: 0;
  font-size: 0.8125rem;
  letter-spacing: 0.006em;
  color: var(--muted);
}

/* No running caption under the camera. The element survives only to carry a
   camera failure, so while it is empty it must take up no room at all --
   :empty plus display:none, because an empty <p> still occupies a line box. */
.sign-status:empty {
  display: none;
}

.stage.live {
  border-color: var(--blush-line);
}

/* ---- accessibility ------------------------------------------------------
   Three independent signals, handled independently. Reduced motion still gets
   feedback, just without movement. */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .audio-viz span {
    animation: none;
    transform: scaleY(0.4);
  }

  .status[data-state="live"]::before {
    animation: none;
  }

  .menu a:active,
  .toggle:active,
  .segment:active,
  select:active,
  input[type="range"]:active::-webkit-slider-thumb {
    transform: none;
  }
}

@media (prefers-reduced-transparency: reduce) {
  header {
    background: var(--header);
    border-bottom: 1px solid var(--line);
  }
}

@media (prefers-contrast: more) {
  :root {
    --muted: var(--text);
    --line: rgba(31, 46, 52, 0.5);
    --tint-strong: rgba(31, 46, 52, 0.3);
    --track: rgba(31, 46, 52, 0.45);
    --tick: rgba(31, 46, 52, 0.65);
    --chrome: var(--header);
  }

  header {
    background: var(--header);
    border-bottom: 1px solid var(--line);
  }

  .stage,
  .genText,
  .settings-card,
  select,
  .toggle {
    border-width: 2px;
  }
}

@media (prefers-contrast: more) {
  :root[data-theme="dark"] {
    --line: rgba(230, 238, 240, 0.45);
    --tint-strong: rgba(230, 238, 240, 0.3);
    --track: rgba(230, 238, 240, 0.5);
    --tick: rgba(230, 238, 240, 0.7);
  }
}