:root {
  color-scheme: light;
  --page: #f7f5ef;
  --ink: #202124;
  --muted: #5f6368;
  --panel: #ffffff;
  --line: #d9d5c8;
  --accent: #177e89;
  --accent-strong: #0f5f69;
  --warm: #e6b450;
  --rose: #c75d5d;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  background: var(--page);
  color: var(--ink);
}

button {
  font: inherit;
}

.app-shell {
  width: min(1080px, calc(100% - 32px));
  min-height: 100vh;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 430px);
  gap: clamp(28px, 6vw, 72px);
  align-items: center;
  padding: 48px 0;
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--accent-strong);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  max-width: 720px;
  margin: 0;
  font-size: clamp(2.45rem, 8vw, 5.8rem);
  line-height: 0.98;
  letter-spacing: 0;
}

.lede {
  max-width: 620px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 2vw, 1.18rem);
  line-height: 1.65;
}

.workspace {
  display: grid;
  gap: 18px;
}

.preview-panel {
  min-height: 420px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgb(23 126 137 / 0.12), transparent 42%),
    linear-gradient(315deg, rgb(230 180 80 / 0.2), transparent 46%),
    var(--panel);
  display: grid;
  place-items: center;
  padding: 28px;
}

.signal-card {
  width: min(100%, 320px);
  min-height: 240px;
  border: 1px solid rgb(32 33 36 / 0.12);
  border-radius: 8px;
  background: rgb(255 255 255 / 0.86);
  box-shadow: 0 24px 60px rgb(32 33 36 / 0.12);
  padding: 26px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  transition:
    transform 180ms ease,
    border-color 180ms ease,
    background 180ms ease;
}

.signal-card[data-mode="bright"] {
  border-color: rgb(230 180 80 / 0.7);
  background: #fff8dc;
  transform: translateY(-8px);
}

.signal-card[data-mode="focus"] {
  border-color: rgb(199 93 93 / 0.65);
  background: #fff4f1;
  transform: translateY(6px);
}

.status-dot {
  width: 16px;
  height: 16px;
  margin-bottom: auto;
  border-radius: 999px;
  background: var(--accent);
  box-shadow: 0 0 0 8px rgb(23 126 137 / 0.12);
}

.signal-card[data-mode="bright"] .status-dot {
  background: var(--warm);
  box-shadow: 0 0 0 8px rgb(230 180 80 / 0.18);
}

.signal-card[data-mode="focus"] .status-dot {
  background: var(--rose);
  box-shadow: 0 0 0 8px rgb(199 93 93 / 0.14);
}

.metric-label {
  margin: 42px 0 8px;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.signal-card strong {
  font-size: 1.8rem;
  line-height: 1.05;
}

.signal-card p:last-child {
  margin: 14px 0 0;
  color: var(--muted);
  line-height: 1.5;
}

.controls {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}

.mode-button {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
}

.mode-button:hover {
  border-color: var(--accent);
}

.mode-button.is-active {
  background: var(--ink);
  color: white;
  border-color: var(--ink);
}

@media (max-width: 820px) {
  .app-shell {
    grid-template-columns: 1fr;
    align-items: start;
  }

  .preview-panel {
    min-height: 340px;
  }
}