解决滑动侧边栏遮挡内容的问题：CSS z-index 属性应用

.sidebar {
   z-index: 2;
   position: fixed; /* 确保 position 不是 static */
}

.content {
   z-index: 1;
   position: relative; /* 确保 position 不是 static */
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Fire Sans", sans-serif;
}

.app {
  display: flex;
  min-height: 100vh;
  background-image: url(../site/images/bg2.jpeg);
}

.sidebar {
  flex: 1 1 0;
  max-width: 300px;
  padding: 2rem 1rem;
  background-color: #053853;
  z-index: 2; /* 添加 z-index 属性 */
  position: fixed; /* 确保 position 不是 static */
}

.sidebar h3 {
  color: #f6da9b;
  font-size: 0.75 rem;
  text-transform: uppercase;
  margin-bottom: 0.5em;
}

.sidebar .menu {
  margin: 0 -1rem;
}

.sidebar .menu .menu-item {
  display: block;
  padding: 1em;
  color: #fff;
  text-decoration: none;
  transition: 0.2 linear;
}

.sidebar .menu .menu-item:hover,
.sidebar .menu .menu-item.is-active {
  color: #3bba9c;
  border-right: 5px solid #3bba9c;
}

.content {
  flex: 1 1 0;
  padding: 2rem;
  margin: 4rem;
  width: 60%;
  border: 3px solid #e9d397;
  text-align: center;
  border-radius: 10px;
  backdrop-filter: blur(10px);
  z-index: 1; /* 添加 z-index 属性 */
  position: relative; /* 确保 position 不是 static */
}

.content h1 {
  color: #fff;
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.content p {
  color: #fff;
}

.menu-toggle {
  display: none;
  position: fixed;
  top: 2rem;
  right: 2rem;
  width: 60px;
  height: 60px;
  border-radius: 99px;
  background-color: #2e3047;
  cursor: pointer;
  z-index: 3; /* 确保 menu-toggle 在 sidebar 上面 */
}

.hamburger {
  position: relative;
  top: calc(50% - 2px);
  left: 50%;
  transform: translate(-50%, -50%);
  width: 32px;
}

.hamburger > span,
.hamburger > span::before,
.hamburger > span::after {
  display: block;
  position: absolute;
  width: 100%;
  height: 4px;
  border-radius: 99px;
  background-color: #fff;
  transition-duration: 0.25s;
}

.hamburger > span::before {
  content: "";
  top: -8px;
}

.hamburger > span::after {
  content: "";
  top: 8px;
}

.menu-toggle.is-active .hamburger > span {
  transform: rotate(45deg);
}
.menu-toggle.is-active .hamburger > span::before {
  top: 0;
  transform: rotate(0deg);
}
.menu-toggle.is-active .hamburger > span::after {
  top: 0;
  transform: rotate(90deg);
}

@media (max-width: 1024px) {
  .sidebar {
    max-width: 200px;
  }
}

@media (max-width: 768px) {
  .menu-toggle {
    display: block;
  }
  .content {
    padding: 2rem;
    margin-top: 8rem;
  }
  .sidebar {
    position: fixed;
    top: 0;
    left: -300px;
    height: 100vh;
    width: 100%;
    max-width: 300px;
    transition: 0.2 linear;
  }
  .sidebar.is-active {
    left: 0;
  }
}