* {
  box-sizing: border-box;
}

:root {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #f5f5f7;
  background: #09090b;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background:
    radial-gradient(circle at top, #27272a 0, #09090b 45%);
}

.app {
  width: min(720px, 94vw);
  height: min(820px, 92vh);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid #27272a;
  border-radius: 24px;
  background: rgba(15, 15, 18, 0.94);
  box-shadow: 0 24px 80px rgba(0,0,0,.45);
}

header {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 20px 22px;
  border-bottom: 1px solid #27272a;
}

.logo {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: #27272a;
  font-size: 24px;
}

h1 {
  margin: 0;
  font-size: 20px;
}

header p {
  margin: 3px 0 0;
  color: #a1a1aa;
  font-size: 13px;
}

.status {
  margin-left: auto;
  color: #86efac;
  font-size: 12px;
}

.chat {
  flex: 1;
  overflow-y: auto;
  padding: 24px;
}

.message {
  display: flex;
  gap: 10px;
  margin-bottom: 18px;
  animation: pop .18s ease-out;
}

.message.user {
  justify-content: flex-end;
}

.avatar {
  width: 32px;
  height: 32px;
  flex: 0 0 32px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: #27272a;
  font-size: 16px;
}

.bubble {
  max-width: 75%;
  padding: 12px 15px;
  border-radius: 16px;
  background: #27272a;
  line-height: 1.5;
  white-space: pre-wrap;
  word-break: break-word;
}

.user .bubble {
  background: #f4f4f5;
  color: #09090b;
  border-bottom-right-radius: 5px;
}

.bot .bubble {
  border-bottom-left-radius: 5px;
}

.composer {
  display: flex;
  gap: 10px;
  padding: 16px;
  border-top: 1px solid #27272a;
}

input {
  min-width: 0;
  flex: 1;
  border: 1px solid #3f3f46;
  outline: none;
  border-radius: 14px;
  padding: 13px 15px;
  color: #fff;
  background: #18181b;
  font-size: 15px;
}

input:focus {
  border-color: #71717a;
}

button {
  border: 0;
  border-radius: 14px;
  padding: 0 18px;
  color: #09090b;
  background: #fff;
  font-weight: 700;
  cursor: pointer;
}

button:disabled {
  opacity: .5;
  cursor: wait;
}

.error {
  min-height: 0;
  padding: 0 18px;
  color: #fca5a5;
  font-size: 13px;
  text-align: center;
}

footer {
  padding: 10px;
  color: #52525b;
  font-size: 11px;
  text-align: center;
}

@keyframes pop {
  from { opacity: 0; transform: translateY(5px); }
  to { opacity: 1; transform: translateY(0); }
}