/* Plain, readable, works with keyboard and screen reader first. System
   font stack, visible focus, light + dark schemes. No webfonts, no
   frameworks — this file is the whole design system. */

:root {
  --bg: #fff;
  --ink: #1a1a1a;
  --muted: #555;
  --line: #d8d8d8;
  --panel: #f6f6f6;
  --accent: #0b5cad;
  --accent-ink: #fff;
  --good: #1c6b2a;
  --bad: #a4262c;
  --warn-bg: #fff4d6;
  --radius: 6px;
  --measure: 68rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141414;
    --ink: #e8e8e8;
    --muted: #b3b3b3;
    --line: #3d3d3d;
    --panel: #1e1e1e;
    --accent: #6cb2f5;
    --accent-ink: #101010;
    --good: #7fd08c;
    --bad: #f08a90;
    --warn-bg: #3a300f;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 1rem;
  line-height: 1.5;
}

.topbar {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2rem;
  align-items: baseline;
  justify-content: space-between;
  max-width: var(--measure);
  margin: 0 auto;
  padding: 1rem 1rem 0.5rem;
  border-bottom: 1px solid var(--line);
}

.brand h1 { font-size: 1.4rem; margin: 0; }
.tagline { margin: 0.1rem 0 0; color: var(--muted); font-size: 0.95rem; }

.account { display: flex; gap: 2rem; margin: 0; }
.account div { margin: 0; }
.account dt { font-size: 0.8rem; color: var(--muted); }
.account dd { margin: 0; font-weight: 600; font-variant-numeric: tabular-nums; }
#device-id { font-family: ui-monospace, monospace; font-weight: 400; font-size: 0.85rem; }

.layout {
  display: grid;
  gap: 1rem;
  max-width: var(--measure);
  margin: 0 auto;
  padding: 1rem;
}
@media (min-width: 60rem) {
  .layout { grid-template-columns: minmax(0, 3fr) minmax(16rem, 2fr); }
  #signup-panel { grid-column: 1 / -1; }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem 1.2rem;
}
.panel h2 { margin-top: 0; font-size: 1.15rem; }

.banner {
  max-width: var(--measure);
  margin: 1rem auto 0;
  padding: 0.7rem 1rem;
  border-radius: var(--radius);
}
.banner.error { background: var(--bad); color: #fff; }

.privacy {
  background: var(--warn-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.6rem 0.8rem;
  font-size: 0.92rem;
}

.row { display: flex; flex-wrap: wrap; gap: 0.7rem 1rem; align-items: end; }
.row label { display: grid; gap: 0.2rem; font-size: 0.9rem; }
.grow { flex: 1 1 12rem; }

.hint { color: var(--muted); font-size: 0.85rem; margin: 0.4rem 0; }
#cost-line { font-variant-numeric: tabular-nums; }

input, select, textarea, button { font: inherit; }
input, select, textarea {
  background: var(--bg);
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.45rem 0.6rem;
}
textarea { width: 100%; resize: vertical; }
input:focus-visible, select:focus-visible, textarea:focus-visible, button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

button {
  background: var(--accent);
  color: var(--accent-ink);
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 0.5rem 1rem;
  cursor: pointer;
}
button:disabled { opacity: 0.45; cursor: default; }
button[aria-pressed="true"] { background: var(--good); }

.messages {
  list-style: none;
  margin: 0.8rem 0;
  padding: 0;
  display: grid;
  gap: 0.6rem;
  max-height: 32rem;
  overflow-y: auto;
}
.messages li {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.5rem 0.7rem;
  background: var(--bg);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.messages .role { display: block; font-size: 0.78rem; color: var(--muted); margin-bottom: 0.15rem; }
.messages .receipt {
  display: block;
  margin-top: 0.4rem;
  font-size: 0.78rem;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.composer-buttons { display: flex; gap: 0.5rem; padding-bottom: 0.15rem; }

.stats { display: grid; grid-template-columns: 1fr 1fr; gap: 0.3rem 1rem; margin: 0.8rem 0; }
.stats div { display: contents; }
.stats dt { color: var(--muted); font-size: 0.85rem; }
.stats dd { margin: 0; font-variant-numeric: tabular-nums; }

.foot {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 0 1rem 2rem;
  color: var(--muted);
  font-size: 0.85rem;
}