:root {
  --ideal-viewport-width: 1920;
}

/* 预定义样式开始 */
body,
div,
ol,
ul,
li,
dl,
dt,
dd,
h1,
h2,
h3,
h4,
h5,
h6,
p,
form,
fieldset,
legend,
input {
  margin: 0;
  padding: 0;
}

h1,
h2,
h6 {
  font-size: 100%;
}

ol,
ul {
  list-style: none;
}

img,
fieldset {
  border: 0 none;
  display: block;
}

* {
  padding: 0rem;
  margin: 0rem;
}

ul li {
  list-style: none;
}

a {
  text-decoration: none;
}

.fl {
  float: left;
}

.fr {
  float: right;
}

em {
  font-style: normal;
}

body {
  font: 14px/1.5;
  background-color: #fff;
  font-size: 16px;
  font-family: Microsoft YaHei, Microsoft YaHei-Regular;
  min-width: 1200px;
}

i {
  font-style: normal;
}

.maximum .head {
  width: calc(1500*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  height: calc(80*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  margin: 0 auto;
  display: flex;
  justify-content: flex-end;
}
.maximum .head ul {
  display: flex;
  margin-top: calc(39*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
}
.maximum .head ul li {
  margin-left: calc(30*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
}
.maximum .head ul li a {
  font-size: calc(14*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  color: #333333;
}
.maximum .head_band {
  width: 100%;
  height: calc(450*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
}
.maximum .head_band img {
  width: 100%;
  height: 100%;
}
.btn {
  width: 100%;
  height: calc(234*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  background: #1b1b1b;
  margin-top: calc(62*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
}
.btn .btn_top ul {
  padding-top: calc(56*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  display: flex;
  justify-content: center;
}
.btn .btn_top ul li {
  color: #fff;
}
.btn .btn_top ul span {
  color: #fff;
  margin: 0 calc(20*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
}
.btn .btn_er {
  width: calc(90*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  height: calc(90*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
  background: #b0b0b0;
  margin: 0 auto;
  margin-top: calc(39*(clamp(1200px, 100vw, 3840px) / var(--ideal-viewport-width)));
}