body {
  font-family: "Segoe UI", sans-serif;
  background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
  color: #fff;
  display: flex;
  flex-direction: column;
  height: 100vh;
  margin: 0;
}
header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px;
  font-size: 1.2rem;
  font-weight: bold;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(5px);
}
#chat {
  flex: 1;
  padding: 80px 15px 15px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.message {
  padding: 12px 16px;
  border-radius: 15px;
  max-width: 75%;
  line-height: 1.4;
  white-space: pre-wrap;
}
.user { background: #0078ff; align-self: flex-end; }
.bot { background: rgba(255,255,255,0.1); align-self: flex-start; }
#inputBox {
  display: flex;
  gap: 6px;
  padding: 10px;
  background: rgba(0,0,0,0.4);
  position: relative;
}
#input {
  flex: 1;
  padding: 10px;
  border: none;
  border-radius: 8px;
}
button, label {
  padding: 10px 15px;
  border-radius: 8px;
  border: none;
  background: #0078ff;
  color: #fff;
  cursor: pointer;
}
#uploadMenu {
  display: none;
  position: absolute;
  bottom: 55px;
  left: 10px;
  background: #2c2c3c;
  border-radius: 10px;
  padding: 10px;
  box-shadow: 0 0 10px rgba(0,0,0,0.5);
}
#uploadMenu button {
  width: 100%; padding: 10px; margin: 5px 0;
  border: none; border-radius: 8px;
  background: #0078ff; color: #fff; font-size: 1rem;
  cursor: pointer;
}
input[type=file] { display: none; }
#stopContainer {
  text-align: center;
  margin: 5px;
  display: none;
}
#stopBtn {
  padding: 6px 12px;
  background: #ff5555;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}
img.preview {
  max-width: 150px;
  border-radius: 8px;
  margin-top: 5px;
}