body {
    background: url('hoian.jpg') no-repeat center center fixed;
    background-size: cover;
    color: white;
    font-family: 'Poppins', sans-serif;
    text-align: center;
    display: flex;
    align-items: center; /* Căn giữa theo chiều dọc */
    justify-content: center; /* Căn giữa theo chiều ngang */
    height: 100vh; /* Chiều cao bằng toàn bộ màn hình */
}
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: -1;
    backdrop-filter: blur(8px);
}
.card {
    background: rgba(255, 255, 255, 0.2);
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    transition: transform 0.3s;
}
.card:hover {
    transform: scale(1.05);
}
.social-icons {
    margin-top: 20px;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
}
.social-icons a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 150px;
    padding: 10px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.2);
    transition: 0.3s;
    text-decoration: none;
    font-weight: bold;
    color: white;
    gap: 5px;
}
.social-icons a:hover {
    transform: scale(1.1);
    background: rgba(255, 255, 255, 0.4);
}
.button {
    display: inline-block;
    background: #ff9800;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: bold;
    transition: 0.3s;
}
.button:hover {
    background: #e65100;
}

.shapes-3 {
    width: 150px;
    height: 150px;
    display: flex;
    transform:rotate(45deg);
    animation: sh3-0 1.5s infinite linear;
  }
  .shapes-3:before,
  .shapes-3:after {
    content: "";
    width:50%;
    background:#ff00ff;
    clip-path: polygon(0 50%,100% 0,100% 100%);
    animation: inherit;
    animation-name: sh3-1;
  }
  .shapes-3:after {
    clip-path: polygon(0 0,100% 50%,0% 100%);
    animation-name: sh3-2;
  }
  @keyframes sh3-0 {
    25% {width:150px;height:150px;transform:rotate(0)}
    50% {width:150px;height:150px}
    75% {width:70.70px;height:35.35px}
    100%{width:70.70px;height:35.35px;transform:rotate(0)}
  }
  @keyframes sh3-1 {
    0%,25% {clip-path: polygon(0 50% ,100% 0,100% 100%);transform:translate(0.3px)}
    50%    {clip-path: polygon(0 50% ,100% 0,100% 100%);transform:translate(-5px)}
    75%    {clip-path: polygon(0 100%,0    0,100% 100%);transform:translate(-5px)}
    100%   {clip-path: polygon(0 100%,0    0,100% 100%);transform:translate(17.7px)}
  }
  @keyframes sh3-2 {
    0%,25% {clip-path: polygon(0 0,100% 50%,0    100%);transform:translate(-0.3px) }
    50%    {clip-path: polygon(0 0,100% 50%,0    100%);transform:translate(5px) }
    75%    {clip-path: polygon(0 0,100% 0  ,100% 100%);transform:translate(5px)}
    100%   {clip-path: polygon(0 0,100% 0  ,100% 100%);transform:translate(-17.7px) }
  }
.show {
    animation: fadeIn 1s ease-in-out;
}
@keyframes fadeIn {
    0% { opacity: 0; transform: translateY(-20px); }
    100% { opacity: 1; transform: translateY(0); }
}
.content {
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
}
.typing {
    font-size: 2rem;
    font-weight: bold;
    display: inline-block;
    border-right: 3px solid white;
    white-space: nowrap;
    overflow: hidden;
    width: max-content;
}