如何修复明暗主题开关

Question

我遵循了iTunes API的简单教程，并添加了一个选项，可从暗色切换为亮色。但是，每当我切换到深色主题时（当您搜索艺术家时），页面的上半部分才会更改。下半部分仍然是浅色主题。我不确定CSS哪里出问题了。

body {
  font-family: 'Montserrat Alternates', sans-serif;
  color: #fff;
  background-image: linear-gradient(to bottom right, purple, yellow);
  background-attachment: fixed;
  font-size: 14px;
  margin: 0;
  padding: 0;
  height: 100%;
}

/* Dark/Light Toggle */
section {
  position: absolute;
  width: 100%;
  height: 100vh;
  box-sizing: border-box;
  background-attachment: fixed;
}

section.dark {
  background-image: linear-gradient(to bottom right, black, white);
}

ul {
  position: absolute;
  top: 20px;
  left: 20px;
  margin: 0;
  padding: 0;
  width: 20%;
  height: 30px;
  z-index: 1;
  border: 2px solid #000;
  cursor: pointer;
  box-sizing: border-box;
  overflow: hidden;
}

ul li {
  list-style: none;
  width: 100%;
  height: 60px;
  text-align: center;
  text-transform: uppercase;
  transition: 0.5s;
}

ul.active li {
  transform: translateY(-30px);
  background: #262626;
}

ul li span{
  display: block;
  height: 30px;
  width: 100%;
  line-height: 30px;
  color: #fff;
}

ul li span:nth-child(1) {
  color: #fff;
}