@charset "utf-8";

*,
::before,
::after {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}
/* 清除所有网站自带的默认边距 */
ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

body {
  font-family: 'Courier New', Courier, monospace;
  font-size: 16px;
  color: black;
  line-height: 1;
  background-color: rgb(255, 255, 255);
}

img {
  max-width: 100%;
}

/* ------------------------------------------ */

/* 让 header 覆盖在画面上 */
.header {
  position: fixed;
  /* 让header可以移动用fixed */
  top: 0;
  left: 0;
  z-index: 10;

  width: 100%;
  height: 60px;

  color: rgba(235, 238, 226, 0.9);
  background-color: rgba(5, 10, 10, 0.18);

  /* 模糊 header 后面的画面 */
  backdrop-filter:
    blur(4px)
    contrast(1.2)
    saturate(0.75);

  /* Safari 浏览器需要这一行 */
  -webkit-backdrop-filter:
    blur(4px)
    contrast(1.2)
    saturate(0.75);

  /* border-bottom: 1px solid rgba(220, 235, 228, 0.15); */
}

/* 在透明 header 上加入细小的像素网格 */
.header::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;

  background-image:
    linear-gradient(
      rgba(255, 255, 255, 0.05) 1px,
      transparent 1px
    ),
    linear-gradient(
      90deg,
      rgba(255, 255, 255, 0.05) 1px,
      transparent 1px
    );

  background-size: 5px 5px;
  opacity: 0.35;
}

/* ------------------------------------------ */

.header-inner {
  max-width: 1200px;/* 网站header最大宽度 */
  height: 60px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 40px;
  padding-right: 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 1;
  position: relative;
}

.site-menu ul {
  display: flex;/* 横着显示内容 */
  
}

.site-menu ul li{
  margin-left: 20px;
  margin-right: 20px/* 调整导航栏目中每个li的间距 */;
  /* background-color: rgb(229, 229, 229); */
  color: white;
}

.site-menu ul li:hover {
  background-color: yellow;
  color: black;
}