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

a {
  text-decoration: none;
  color: #000;
}

body {
  font-family: "Roboto", sans-serif;
  background-color: #f5f5f5;
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
}

.app {
  background: url(./images/bg.webp);
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center 20%;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: flex-end;
  overflow: hidden;
  position: relative;
}

.collection img {
  width: 40%;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0;
  transition: opacity 1s;
}
.collection img.active {
  opacity: 1;
}

.content {
  width: 45%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.btn {
  width: 65%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  margin-bottom: 2%;
}

@keyframes scaleAnimation {
  0%,
  100% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.1);
  }
}

.btn a img {
  animation: scaleAnimation 1.5s infinite ease-in-out;
}

.title-mb {
  display: none;
}

.logo {
  display: none;
}

.text-mb,
.text {
  display: none;
}

.bg-qt {
  background: url(./images/bg-qt.webp);
  background-size: 100% 100%;
  width: 20%;
  height: 15%;
  position: absolute;
  top: 3%;
  left: 2%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 10px;
}

.countdown {
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: Arial, sans-serif;
  gap: 20px;
  width: 100%;
  position: relative;
  margin-left: 20%;
}

.time-block {
  position: relative;
  top: 50%;
  transform: translateY(-50%);
  border-radius: 10px;
  padding: 5px 0;
  text-align: center;
  width: 15%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  margin-top: 5%;
}

.number {
  font-size: 4rem;
  font-weight: bold;
  color: #fff;
  border-radius: 10px;
  margin-top: 5%;

  background: linear-gradient(180deg, #ffffff, #ffffff, #8cdbf2);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;

  -webkit-text-stroke: 1px #0320ce;
}

.colon {
  position: relative;
  top: 48%;
  font-weight: bold;
  transform: translateY(-50%);
  font-size: 5rem;
  margin: 0 -3%;
  background: linear-gradient(180deg, #ffffff, #ffffff, #8cdbf2);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;

  /* Viền trắng */
  -webkit-text-stroke: 1px #0320ce;
}

@media screen and (max-width: 768px) {
  .app {
    background: url(./images/bg-mb.webp);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center bottom;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    overflow: hidden;
  }

  .content {
    width: 90%;
    height: 100%;
    justify-content: flex-start;
    margin: 0;
  }

  .countdown {
    gap: 10px;
  }

  .number {
    font-size: 2rem;
    font-weight: bolder;
  }

  .colon {
    font-size: 2rem;
    top: 40%;
  }

  .bg-qt {
    position: relative;
    top: 0;
    left: -2%;
    width: 70%;
    height: 12%;
    margin-bottom: 2%;
  }

  .collection {
    position: relative;
    width: 100%;
    margin: 3% 0 5%;
  }

  .collection img {
    width: 90%;
  }

  .btn {
    width: 90%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
  }

  .title {
    display: none;
  }

  .text {
    display: block;
    margin-bottom: -30%;
    width: 89%;
  }

  .title-mb {
    margin-top: 5%;
    width: 50%;
    display: block;
  }
}