/* 整体容器 */
.container {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  height: 550px;
  background-size: cover;
  position: relative; /* 确保背景图在表单之下 */
}

/* 背景图片 */
.background-image {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: -1; /* 将背景图置于底层 */
}

/* 表单容器 */
.form-container {
  display: flex;
  flex-direction: column;
  align-items: center; /* 水平居中 */
  justify-content: center; /* 垂直居中，如果需要的话 */
  width: 90%;
  max-width: 400px;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, .1);
  background-color: rgba(255, 255, 255, 0.8); /* 半透明背景 */
}

/* 欢迎语 */
.welcome-message {
  font-size: 20px;
  text-align: center; /* 文本内部居中 */
  margin-bottom: 20px;
}

/* 输入框 */
.input {
  width: 90%;
  margin-bottom: 10px;
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 5px;
  font-size: 16px;
}

/* 登录按钮 */
.btn {
  width: 100%;
  padding: 10px;
  color: white;
  background-color: #3EC01E;
  border: none;
  border-radius: 5px;
  transition: background-color .3s;
}

.btn:hover {
  background-color: #179414;
}

/* 错误消息 */
.error {
  color: red;
  text-align: center;
  margin-top: 10px;
}