body {
  background-color: #000000;
  font-family: 'Courier New', Courier, monospace;
  color: #00ff00;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  background-image: repeating-linear-gradient(
    0deg,
    rgba(0, 255, 0, 0.1),
    rgba(0, 255, 0, 0.1) 1px,
    transparent 1px,
    transparent 2px
  );
  background-size: 100% 2px;
}

.chat-window {
  width: 90%;
  max-width: 400px;
  border: 3px solid #00ff00;
  padding: 10px;
  background-color: #001a00;
  box-shadow: 0 0 20px #00ff00;
  overflow: hidden;
}

.chat-header {
  font-weight: bold;
  text-align: center;
  border-bottom: 1px solid #00ff00;
  padding-bottom: 5px;
  margin-bottom: 10px;
}

.chat-body {
  max-height: 300px;
  overflow-y: auto;
  padding-right: 5px;
}

.message {
  margin-bottom: 10px;
}

.system {
  font-style: italic;
  color: #00ff00;
}