:root {
  --bg: #f6f5f1;
  --surface: #ffffff;
  --text: #17171a;
  --muted: #6b6b73;
  --line: #e3e1da;
  --accent: #1f5eff;
  --accent-text: #ffffff;
  --ok: #138a4b;
  --ok-bg: #e3f5ea;
  --warn: #9a6400;
  --warn-bg: #fdf1d8;
  --err: #c2352b;
  --err-bg: #fbe6e3;
  --code-bg: #efeee9;
  --violet: #7c5cff;
  --radius: 3px;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121212;
    --surface: #1c1c1f;
    --text: #ececef;
    --muted: #9a9aa3;
    --line: #2d2d32;
    --accent: #5b8cff;
    --accent-text: #0b0b0d;
    --ok: #4cd08a;
    --ok-bg: #12301f;
    --warn: #f0b54a;
    --warn-bg: #33270f;
    --err: #ff7b70;
    --err-bg: #3a1714;
    --code-bg: #232327;
    --violet: #a78bfa;
  }
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 var(--sans);
}

main {
  max-width: 560px;
  margin: 0 auto;
  padding: max(20px, env(safe-area-inset-top)) 16px max(40px, env(safe-area-inset-bottom));
}

header h1 {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 8px 0 4px;
  font: 700 28px/1.1 var(--mono);
  letter-spacing: -0.02em;
}

.mark {
  width: 22px;
  height: 22px;
  border-radius: 2px;
  background:
    linear-gradient(var(--text), var(--text)) 3px 3px / 7px 7px no-repeat,
    linear-gradient(var(--text), var(--text)) 12px 12px / 7px 7px no-repeat,
    linear-gradient(var(--text), var(--text)) 12px 3px / 7px 2px no-repeat,
    linear-gradient(var(--text), var(--text)) 3px 12px / 2px 7px no-repeat;
  outline: 2px solid var(--text);
  outline-offset: -2px;
}

header .top { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.gh {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  text-decoration: none;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 2px;
}
.gh:hover { color: var(--text); border-color: var(--muted); }
.tagline { margin: 4px 0 20px; color: var(--muted); }
.tagline a { color: inherit; }

code, pre { font-family: var(--mono); font-size: 0.875em; }
:not(pre) > code { background: var(--code-bg); padding: 1px 5px; border-radius: 2px; }

/* camera */
#viewfinder {
  position: relative;
  margin-bottom: 12px;
  border-radius: var(--radius);
  overflow: hidden;
  background: #000;
  aspect-ratio: 1 / 1;
}
#viewfinder[hidden] { display: none; }
#video { width: 100%; height: 100%; object-fit: cover; display: block; }
.reticle {
  position: absolute;
  inset: 14%;
  border-radius: 2px;
  box-shadow: 0 0 0 100vmax rgba(0, 0, 0, 0.35);
  outline: 2px solid rgba(255, 255, 255, 0.85);
  transition: outline-color 0.15s;
}
#viewfinder.hit .reticle { outline-color: #4cd08a; outline-width: 4px; }
#stop-scan {
  position: absolute;
  right: 10px;
  bottom: 10px;
  background: rgba(0, 0, 0, 0.55);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.3);
}

/* slots */
#slots { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.slot {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  min-height: 72px;
}
.num {
  flex: none;
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: 2px;
  border: 1.5px dashed var(--muted);
  color: var(--muted);
  font: 600 14px var(--mono);
}
.slot .body { flex: 1; min-width: 0; }
.slot .title { font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.slot .sub { color: var(--muted); font-size: 14px; overflow-wrap: anywhere; }
.slot .sub .id { font-family: var(--mono); font-size: 12px; }
.pill {
  flex: none;
  font-size: 12px;
  font-weight: 600;
  padding: 3px 9px;
  border-radius: 2px;
  white-space: nowrap;
}
.pill:empty { display: none; }

.slot[data-state="busy"] .num { border-style: solid; border-color: var(--accent); color: var(--accent); }
.slot[data-state="busy"] .pill { background: var(--code-bg); color: var(--muted); }
.slot[data-state="busy"] .pill::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: 6px;
  border-radius: 50%;
  border: 1.5px solid currentColor;
  border-right-color: transparent;
  animation: spin 0.8s linear infinite;
  vertical-align: -1px;
}
.slot[data-state="ok"] .num,
.slot[data-state="done"] .num { border: none; background: var(--ok); color: var(--surface); }
.slot[data-state="ok"] .pill { background: var(--ok-bg); color: var(--ok); }
.slot[data-state="done"] .pill { background: var(--ok); color: var(--surface); }
.slot[data-state="error"] { border-color: var(--err); }
.slot[data-state="error"] .num { border: none; background: var(--err); color: var(--surface); }
.slot[data-state="error"] .pill { background: var(--err-bg); color: var(--err); }

@keyframes spin { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) { .slot .pill::before { animation: none; } }

#message { min-height: 1.5em; margin: 12px 2px; font-size: 15px; }
#message:empty { margin: 6px 0; }
#message.ok { color: var(--ok); font-weight: 600; }
#message.warn { color: var(--warn); }
#message.err { color: var(--err); }

/* buttons */
.actions { display: flex; gap: 10px; flex-wrap: wrap; }
button {
  font: 600 16px var(--sans);
  border-radius: 2px;
  padding: 13px 18px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
}
button.primary { flex: 1; background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
button.small { font-size: 14px; padding: 7px 12px; border-radius: 2px; }
button:disabled { opacity: 0.5; cursor: default; }
button[hidden] { display: none; }
button:focus-visible, input:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

#paste-box { margin-top: 14px; color: var(--muted); font-size: 15px; }
#paste-box summary { cursor: pointer; padding: 4px 0; }
#paste-form { display: flex; gap: 8px; margin-top: 8px; }
#paste {
  flex: 1;
  min-width: 0;
  font: 14px var(--mono);
  padding: 11px 12px;
  border-radius: 2px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
}

#diag { margin-top: 6px; color: var(--muted); font-size: 15px; }
#diag summary { cursor: pointer; padding: 4px 0; }
#diag .note { margin: 6px 0; }
#diag-log {
  margin: 8px 0 0;
  max-height: 50vh;
  overflow: auto;
  padding: 10px;
  border-radius: 2px;
  background: var(--code-bg);
  color: var(--text);
  font: 11px/1.45 var(--mono);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

/* docs */
#setup { margin-top: 40px; border-top: 1px solid var(--line); padding-top: 8px; }
#setup h2 { font-size: 20px; margin: 24px 0 8px; }
#setup h3 { font-size: 15px; margin: 20px 0 8px; color: var(--muted); font-weight: 600; }
#setup p { margin: 8px 0; }
.cmd {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 6px 0;
  background: var(--code-bg);
  border-radius: 2px;
  padding: 10px 12px;
  cursor: copy;
}
.cmd .who {
  flex: none;
  width: 4.6em;
  font-size: 12px;
  color: var(--muted);
}
.cmd pre { margin: 0; flex: 1; min-width: 0; white-space: pre-wrap; overflow-wrap: anywhere; }
.cmd.copied::after {
  content: "copied";
  position: absolute;
  right: 8px;
  top: 6px;
  font-size: 11px;
  color: var(--ok);
}
@media (max-width: 480px) {
  .cmd { display: block; }
  .cmd .who { display: block; width: auto; margin-bottom: 2px; }
}
.note { color: var(--muted); font-size: 14px; }

/* animated diagrams */
.diagrams { display: grid; gap: 14px; margin: 12px 0 18px; }
figure.dg {
  margin: 0;
  padding: 12px 12px 12px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
figure.dg svg { display: block; width: 100%; height: auto; }
figure.dg figcaption { margin-top: 8px; font-size: 14px; color: var(--muted); }
figure.dg figcaption b { color: var(--text); }
.dg-anim text { font: 500 11px var(--sans); fill: var(--text); }
.dg-anim .b { font-weight: 700; font-size: 12px; }
.dg-anim .small { font-size: 9.5px; }
.dg-anim .muted { fill: var(--muted); }
.dg-anim .okt { fill: var(--ok); }
.dg-anim .steps text { font-weight: 600; font-size: 11.5px; }
.dg-anim .dev { fill: var(--code-bg); stroke: var(--muted); stroke-width: 1.2; }
.dg-anim .scr { fill: var(--bg); }
.dg-anim .untrusted { fill: var(--surface); stroke: var(--violet); stroke-width: 1.3; stroke-dasharray: 4 3; }
.dg-anim .faded { opacity: 0.45; }
.dg-anim .link { fill: none; stroke: var(--accent); stroke-width: 2; stroke-dasharray: 5 4; }
.dg-anim .fallback { fill: none; stroke: var(--violet); stroke-width: 1.3; stroke-dasharray: 3 4; opacity: 0.5; }
.dg-anim .pkt { fill: var(--accent); }
.dg-anim .pkt.intro { fill: var(--warn); }
.dg-anim .beam { fill: var(--accent); fill-opacity: 0.18; stroke: var(--accent); stroke-opacity: 0.5; }
.dg-anim .direct { stroke: var(--ok); stroke-width: 8; stroke-linecap: round; stroke-opacity: 0.55; }
.dg-anim .pipe { fill: var(--ok); fill-opacity: 0.22; stroke: var(--ok); stroke-width: 1.5; }
.dg-anim .data { fill: var(--warn); }
.dg-anim .lockbg { fill: var(--surface); stroke: var(--ok); stroke-width: 1.5; }
.dg-anim .ok { fill: var(--ok); }
.dg-anim .ok-stroke { stroke: var(--ok); }
.how { padding-left: 20px; }
.how li { margin: 6px 0; }
.foot { color: var(--muted); font-size: 14px; margin-top: 24px; }
a { color: var(--accent); }

/* terse, terminal-ish headings */
h2, h3, summary, .slot .title, figure.dg figcaption b { font-family: var(--mono); letter-spacing: -0.01em; }
#how h2, #setup h2 { font-size: 18px; margin: 28px 0 10px; }
#setup h3 { color: var(--text); font-size: 14px; }
.how { padding-left: 18px; font-size: 14px; color: var(--muted); }
.how li { margin: 3px 0; }
#how { margin-top: 28px; border-top: 1px solid var(--line); }