* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  background: #0b1020;
  color: #e8edf7;
  font-family: Arial, sans-serif;
}
.shell {
  width: min(760px, 100%);
  background: #141b2d;
  border: 1px solid #2b3652;
  border-radius: 18px;
  padding: 24px;
  box-shadow: 0 24px 70px #0007;
}
header { margin-bottom: 20px; }
h1 { margin: 10px 0 6px; }
header p, .status { color: #9eabc5; }
.badge {
  display: inline-block;
  padding: 6px 10px;
  border-radius: 999px;
  background: #f6821f22;
  color: #ff9d4d;
  font-size: 13px;
}
.messages {
  min-height: 300px;
  max-height: 55vh;
  overflow-y: auto;
  padding: 16px;
  background: #0d1323;
  border-radius: 12px;
}
.message {
  width: fit-content;
  max-width: 85%;
  margin: 10px 0;
  padding: 12px 14px;
  border-radius: 12px;
  white-space: pre-wrap;
  line-height: 1.45;
}
.assistant { background: #26314b; }
.user {
  margin-left: auto;
  background: #f6821f;
  color: #111;
}
.error { background: #7f1d1d; }
form {
  display: flex;
  gap: 10px;
  margin-top: 16px;
}
textarea {
  flex: 1;
  min-height: 70px;
  resize: vertical;
  padding: 12px;
  border: 1px solid #3a4664;
  border-radius: 10px;
  background: #0d1323;
  color: inherit;
  font: inherit;
}
button {
  padding: 0 22px;
  border: 0;
  border-radius: 10px;
  background: #f6821f;
  color: #111;
  font-weight: bold;
  cursor: pointer;
}
button:disabled { opacity: .55; cursor: wait; }
.status { margin-bottom: 0; font-size: 13px; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
}