/* 加载动画覆盖层 */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  z-index: 9999;
  transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loading-overlay.hidden {
  opacity: 0;
  visibility: hidden;
}

.spinner-border {
  width: 3rem;
  height: 3rem;
  border-width: 0.2em;
  color: #fff;
  animation: spinner-border 0.75s linear infinite;
}

@keyframes spinner-border {
  to {
    transform: rotate(360deg);
  }
}

.loading-overlay p {
  color: #fff;
  font-size: 18px;
  margin-top: 20px;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

/* 页面内容初始隐藏 */
.page-content {
  opacity: 0;
  transition: opacity 0.5s ease;
  width: 100%;
  min-height: 100vh;
}

.page-content.visible {
  opacity: 1;
}

/* 确保页面内容正常布局 */
.page-content > .container {
  /* 继承原有的容器样式属性 */
  margin-left: auto;
  margin-right: auto;
}

/* 特殊处理全屏布局的页面 */
body > .page-content {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}