* {
  padding: 0;
  margin: 0;
}

body {
  background: #252525;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}

img {
  display: block;
  width: 100%;
}

.main {
  width: 550px;
  margin: 0 auto 0;
}

.btn11 {
  position: fixed;
  bottom: 0;
  right: 0;
  left: 0;
  text-align: center;
  z-index: 100;
  background: rgba(0, 0, 0, 1);
  width: 550px;
  margin: 0 auto;
}

.btn11 a {
  display: inline-block;
  text-align: center;
  font-weight: bold;
  background: #36bc49;
  color: #fff;
  margin: 15px 0;
  height: 48px;
  line-height: 48px;
  border-radius: 5px;
  text-decoration: none;
  width: 100%;
}

@media (max-width: 768px) {
  .main,
  .btn11 {
    width: 100%;
  }
}