:root {
  color-scheme: dark;
  --bg: #07100d;
  --panel: #0d1714;
  --panel-soft: #09120f;
  --line: #246c7a;
  --text: #e3fff9;
  --muted: #7fb8c4;
  --accent: #7ed7ff;
  --accent-strong: #b8f0ff;
  --button: #11242a;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
  margin: 0;
  background:
    linear-gradient(rgba(255, 255, 255, 0.018) 50%, rgba(0, 0, 0, 0.04) 50%),
    radial-gradient(circle at 50% 0%, #10242d 0, var(--bg) 58%);
  background-size: 100% 4px, auto;
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Noto Sans KR", "Segoe UI", system-ui, sans-serif;
}

.chat-shell {
  display: grid;
  gap: 14px;
  width: min(980px, 100%);
  min-height: 100vh;
  margin: 0 auto;
  padding: 18px;
}

.chat-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 14px;
  border-bottom: 1px solid color-mix(in srgb, var(--line) 76%, transparent);
}

h1 {
  margin: 0;
  color: var(--accent-strong);
  font-size: 22px;
}

p {
  margin: 5px 0 0;
  color: var(--muted);
}

button {
  min-height: 36px;
  border: 1px solid var(--line);
  background: var(--button);
  color: var(--text);
  padding: 0 12px;
  cursor: pointer;
}

button:hover,
button:focus-visible {
  border-color: var(--accent);
  color: var(--accent-strong);
}

.chat-summary {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
}

.chat-summary div {
  min-height: 72px;
  padding: 11px 12px;
  border: 1px solid color-mix(in srgb, var(--line) 72%, transparent);
  background: color-mix(in srgb, var(--panel-soft) 88%, #000 12%);
}

.chat-summary span {
  display: block;
  color: var(--muted);
  font-size: 12px;
}

.chat-summary strong {
  display: block;
  margin-top: 7px;
  overflow: hidden;
  color: var(--accent-strong);
  font-size: 18px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-list {
  display: grid;
  gap: 8px;
}

.chat-row {
  display: grid;
  grid-template-columns: 168px 112px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
  padding: 11px 12px;
  border: 1px solid color-mix(in srgb, var(--line) 58%, transparent);
  background: color-mix(in srgb, var(--panel) 88%, #000 12%);
}

.chat-row time,
.chat-row strong {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.chat-row time {
  color: var(--muted);
  font-size: 13px;
}

.chat-row strong {
  color: var(--accent-strong);
}

.chat-row p {
  margin: 0;
  color: var(--text);
  overflow-wrap: anywhere;
  white-space: pre-wrap;
}

.empty {
  padding: 28px 14px;
  border: 1px solid color-mix(in srgb, var(--line) 56%, transparent);
  background: color-mix(in srgb, var(--panel) 84%, #000 16%);
  color: var(--muted);
  text-align: center;
}

@media (max-width: 720px) {
  .chat-shell {
    padding: 12px;
  }

  .chat-topbar {
    align-items: stretch;
    flex-direction: column;
  }

  .chat-summary,
  .chat-row {
    grid-template-columns: 1fr;
  }
}