* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  background: #0d0f12;
  color: #e2e4e9;
  font-family: sans-serif;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.chat-container {
  width: 100%;
  max-width: 720px;
  height: 90vh;
  display: flex;
  flex-direction: column;
  border: 1px solid #1f2430;
  border-radius: 8px;
  overflow: hidden;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  background: #13161b;
  border-bottom: 1px solid #1f2430;
}

.header h1 { font-size: 16px; }

.header button {
  background: transparent;
  border: 1px solid #1f2430;
  color: #5a6070;
  padding: 4px 12px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
}

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.message {
  padding: 12px 16px;
  border-radius: 6px;
  font-size: 14px;
  line-height: 1.6;
  max-width: 80%;
}

.message--user {
  background: #1a1f2e;
  align-self: flex-end;
}

.message--assistant {
  background: #13161b;
  border: 1px solid #1f2430;
  align-self: flex-start;
}

.input-bar {
  display: flex;
  gap: 10px;
  padding: 16px;
  border-top: 1px solid #1f2430;
  background: #13161b;
}

textarea {
  flex: 1;
  background: #0d0f12;
  border: 1px solid #1f2430;
  border-radius: 6px;
  color: #e2e4e9;
  font-size: 14px;
  padding: 10px;
  resize: none;
  height: 44px;
  outline: none;
}

textarea:focus { border-color: #f97316; }

#send-btn {
  background: #f97316;
  border: none;
  border-radius: 6px;
  color: white;
  padding: 0 20px;
  cursor: pointer;
  font-size: 14px;
}

#send-btn:hover { opacity: 0.85; }