* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body, html {
  height: 100%;
  font-family: "Microsoft YaHei", sans-serif;
  color: white;
}

.background {
  background-image: url('https://555.588b.cn/down.php/899b47618a64d08e17dd904db24fe549.jpg');
  background-size: cover;
  background-position: center;
  min-height: 100vh;
  padding: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.content {
  text-align: center;
  max-width: 600px;
  margin: auto;
}

.title {
  font-size: 2.8em;
  font-weight: bold;
  color: #FFFFFF;
  margin-bottom: 20px;
}

.desc {
  font-size: 1.3em;
  margin: 10px 0;
}

.tag-group {
  margin: 20px 0;
}

.tag {
  display: inline-block;
  background-color: rgba(0,0,0,0.6);
  border: 1px solid gold;
  border-radius: 5px;
  padding: 5px 12px;
  margin: 0 5px;
  font-size: 1em;
  color: #ffd700;
}

.version {
  margin: 15px 0;
  font-size: 0.95em;
  color: #ccc;
}

.buttons {
  margin: 20px 0;
}

.btn {
  background-color: white;
  color: teal;
  border: none;
  padding: 12px 20px;
  margin: 10px;
  font-size: 1.1em;
  border-radius: 50px;
  cursor: pointer;
  min-width: 180px;
  font-weight: bold;
}

.phone {
  margin-top: 30px;
}

.phone img {
  width: 280px;
  border-radius: 20px;
  box-shadow: 0 0 20px rgba(0,0,0,0.5);
}

.logo {
  margin-top: 20px;
}

.logo img {
  width: 90px;
  border-radius: 50%;
  background-color: white;
  padding: 5px;
}

.float-btn {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background-color: #ff6666;
  border-radius: 50%;
  width: 50px;
  height: 50px;
  text-align: center;
  line-height: 50px;
  font-size: 24px;
  font-weight: bold;
  color: white;
  box-shadow: 0 0 10px rgba(0,0,0,0.5);
  cursor: pointer;
}