:root {
  color-scheme: dark;
  --bg: #090c0b;
  --panel: #121715;
  --line: rgba(225, 235, 229, 0.14);
  --text: #edf2ef;
  --muted: #87908b;
  --mint: #b9f6d2;
  --green: #69e89f;
  --coral: #ff765f;
  --mono: ui-monospace, SFMono-Regular, Consolas, monospace;
  --sans: Inter, system-ui, sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--sans); }
button, input, select { font: inherit; }
[hidden] { display: none !important; }
.sender-shell { width: min(960px, calc(100% - 32px)); margin: 0 auto; padding: 42px 0 60px; }
header { display: flex; align-items: flex-start; justify-content: space-between; gap: 30px; margin-bottom: 34px; }
header a { color: var(--mint); font: 12px var(--mono); text-decoration: none; }
.eyebrow, .label { margin: 0 0 9px; color: var(--muted); font: 10px var(--mono); letter-spacing: .13em; text-transform: uppercase; }
h1, h2 { margin: 0; font-weight: 500; letter-spacing: -.035em; }
h1 { font-size: clamp(36px, 6vw, 64px); }
h2 { font-size: 20px; }
.intro, .manual-panel p, .note { color: var(--muted); font-size: 12px; line-height: 1.65; }
.intro { margin: 12px 0 0; }
.panel { margin-top: 16px; padding: 26px; border: 1px solid var(--line); background: var(--panel); }
.manual-panel, .section-heading, .progress-heading, .actions { display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.manual-panel p { max-width: 530px; margin: 7px 0 0; }
.state { padding: 7px 10px; border: 1px solid var(--line); border-radius: 99px; color: var(--muted); font: 10px var(--mono); text-transform: uppercase; }
.state.live { border-color: rgba(105, 232, 159, .4); color: var(--green); }
.form-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 26px; }
.form-grid label { display: flex; flex-direction: column; gap: 8px; color: var(--muted); font: 11px var(--mono); }
.form-grid label span { display: flex; justify-content: space-between; }
.form-grid small { color: var(--muted); font-size: 9px; font-weight: 400; }
.form-grid .wide { grid-column: span 2; }
input, select { width: 100%; min-height: 39px; padding: 8px 10px; border: 1px solid var(--line); border-radius: 2px; outline: 0; background: #0b0f0e; color: var(--text); font-family: var(--mono); }
input:focus, select:focus { border-color: rgba(185, 246, 210, .5); }
input[type="range"] { min-height: auto; padding: 0; accent-color: var(--coral); }
.estimate { margin: 20px 0 0; color: var(--muted); font: 11px var(--mono); }
.actions { justify-content: flex-start; margin-top: 22px; }
.button { min-height: 38px; padding: 0 15px; border: 1px solid var(--line); border-radius: 2px; background: rgba(255,255,255,.03); color: var(--text); cursor: pointer; font: 11px var(--mono); }
.button:disabled { cursor: not-allowed; opacity: .38; }
.button.primary { border-color: rgba(105,232,159,.45); color: var(--mint); }
.button.danger { border-color: rgba(255,118,95,.45); color: #ff9c8c; }
.button.danger.active { background: rgba(255,118,95,.14); }
.live-panel { min-height: 280px; }
.progress-heading strong { font: 20px var(--mono); }
.progress-heading output { color: var(--mint); font: 13px var(--mono); }
.progress-track { height: 3px; margin: 21px 0; background: rgba(255,255,255,.06); }
.progress-track i { display: block; width: 0; height: 100%; background: var(--coral); transition: width 100ms linear; }
.pattern-key { color: var(--muted); font: 11px/1.6 var(--mono); }
.pattern-preview { display: flex; flex-wrap: wrap; gap: 4px; max-height: 160px; overflow: auto; margin: 12px 0 20px; }
.pattern-preview span { padding: 5px 7px; border: 1px solid var(--line); color: var(--muted); font: 14px var(--mono); }
.pattern-preview .current { border-color: var(--mint); background: rgba(185,246,210,.14); color: var(--mint); }
.pattern-preview .current.load { border-color: var(--coral); background: rgba(255,118,95,.14); color: var(--coral); }
.transmission-grid { display: grid; grid-template-columns: repeat(4, 1fr); border: 1px solid var(--line); }
.transmission-grid div { display: flex; flex-direction: column; gap: 8px; padding: 14px; border-right: 1px solid var(--line); }
.transmission-grid div:last-child { border-right: 0; }
.transmission-grid span { color: var(--muted); font: 9px var(--mono); text-transform: uppercase; }
.transmission-grid strong { font: 16px var(--mono); }
.test-log { max-height: 150px; margin: 18px 0 0; padding: 0; overflow: auto; list-style: none; color: var(--muted); font: 10px/1.5 var(--mono); }
.test-log li { padding: 7px 0; border-top: 1px solid var(--line); }
.test-log .active { color: var(--mint); }
.test-log .complete { color: var(--green); }
.note { margin: 22px 2px 0; }
.remote-panel p { max-width: 590px; margin: 7px 0 0; color: var(--muted); font-size: 11px; line-height: 1.55; }
.pair-controls { display: grid; grid-template-columns: 1fr auto; align-items: end; gap: 12px; margin-top: 20px; padding-top: 18px; border-top: 1px solid var(--line); }
.pair-controls label { display: flex; flex-direction: column; gap: 8px; color: var(--muted); font: 10px var(--mono); text-transform: uppercase; }
.remote-detail { font-family: var(--mono); }
.state.warning { border-color: rgba(255,118,95,.4); color: var(--coral); }

@media (max-width: 700px) {
  .form-grid { grid-template-columns: 1fr 1fr; }
  .form-grid .wide { grid-column: span 2; }
  .transmission-grid { grid-template-columns: 1fr 1fr; }
  .transmission-grid div:nth-child(2) { border-right: 0; }
  .transmission-grid div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
}

@media (max-width: 480px) {
  header, .manual-panel { align-items: stretch; flex-direction: column; }
  .form-grid { grid-template-columns: 1fr; }
  .form-grid .wide { grid-column: auto; }
  .actions { align-items: stretch; flex-direction: column; }
  .pair-controls { grid-template-columns: 1fr; }
}