:root {
  --bg: #f5f7fa; --surface: #fff; --text: #1b2430; --muted: #5b6676;
  --primary: #0b5cab; --border: #dde3ea; --error: #b42318; --error-bg: #fef3f2;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #11161d; --surface: #1a212b; --text: #e6ebf1; --muted: #9aa6b5;
    --primary: #5aa2ff; --border: #2c3644; --error: #ff8a80; --error-bg: #3a1d1b;
  }
}
* { box-sizing: border-box; }
body { margin: 0; font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; background: var(--bg); color: var(--text); }
a { color: var(--primary); }
.container { max-width: 960px; margin: 0 auto; padding: 16px; }
.topbar { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap;
  padding: 10px 16px; background: var(--surface); border-bottom: 1px solid var(--border); }
.brand { font-weight: 700; text-decoration: none; }
.who { display: flex; align-items: center; gap: 12px; color: var(--muted); font-size: 14px; }
.who form { margin: 0; }
h1 { font-size: 24px; margin: 8px 0 12px; }
h2 { font-size: 17px; margin: 0 0 4px; }
.muted { color: var(--muted); }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 16px; margin: 12px 0; }
.narrow { max-width: 400px; margin: 48px auto; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 12px; }
.tile { display: block; margin: 0; text-decoration: none; color: inherit; }
.tile p { margin: 0; color: var(--muted); font-size: 14px; }
.tile.disabled { opacity: .6; }
.badge { display: inline-block; margin-top: 8px; font-size: 12px; padding: 2px 8px; border-radius: 99px; border: 1px solid var(--border); }
.stack { display: grid; gap: 12px; }
label { display: grid; gap: 4px; font-size: 14px; }
input, select { font: inherit; padding: 10px; border: 1px solid var(--border); border-radius: 8px; background: var(--bg); color: var(--text); }
button { font: inherit; padding: 10px 14px; border: 0; border-radius: 8px; background: var(--primary); color: #fff; cursor: pointer; }
button.link { background: none; color: var(--primary); padding: 0; }
.error { color: var(--error); background: var(--error-bg); padding: 8px 12px; border-radius: 8px; }
.table-wrap { overflow-x: auto; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); white-space: nowrap; }
td form { margin: 0; }
textarea { font: inherit; padding: 10px; border: 1px solid var(--border); border-radius: 8px; background: var(--bg); color: var(--text); resize: vertical; }
[hidden] { display: none !important; }

/* Channel test page (stage 3) */
.channel { display: grid; gap: 12px; grid-template-columns: minmax(0, 1fr); }
@media (min-width: 800px) { .channel { grid-template-columns: 280px minmax(0, 1fr); } }
.conv-list { margin: 0; padding: 8px; display: grid; gap: 4px; align-content: start; max-height: 70vh; overflow-y: auto; }
.conv { display: grid; padding: 8px 10px; border-radius: 8px; text-decoration: none; color: inherit; font-size: 14px; }
.conv.active, .conv:hover { background: var(--bg); }
.conv .muted { font-size: 12px; overflow-wrap: anywhere; }
.chat { margin: 0; display: grid; gap: 12px; min-width: 0; }
.chat-head { display: flex; justify-content: space-between; gap: 8px; flex-wrap: wrap; align-items: start; }
.chat-head .muted { font-size: 13px; }
.badge.ok { border-color: #2e7d32; color: #2e7d32; }
.badge.warn { border-color: #b26a00; color: #b26a00; }
.messages { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; max-height: 55vh; overflow-y: auto; }
.msg { display: flex; }
.msg.outgoing { justify-content: flex-end; }
.bubble { max-width: 80%; padding: 8px 12px; border-radius: 12px; background: var(--bg); border: 1px solid var(--border); overflow-wrap: anywhere; }
.msg.outgoing .bubble { background: color-mix(in srgb, var(--primary) 14%, var(--surface)); }
.bubble p { margin: 4px 0 0; white-space: pre-wrap; }
.bubble img { max-width: 100%; max-height: 240px; border-radius: 8px; display: block; }
.meta { display: block; font-size: 12px; color: var(--muted); margin-top: 4px; }
.error-text { color: var(--error); }