* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: 'Segoe UI', Tahoma, sans-serif;
    background: #0a0a0a;
    color: #fff;
    text-align: center;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}
header {
    padding: 30px 20px 10px;
}
header h1 {
    font-size: 2rem;
    font-weight: 400;
    color: #e0c4ff;
}
header p {
    color: #aaa;
    margin-top: 10px;
}
main {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 20px;
}
#viewer-container {
    width: 100%;
    max-width: 800px;
    aspect-ratio: 3 / 4;
    background: #1a1a1a;
    border-radius: 24px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0,0,0,0.7);
    margin-bottom: 20px;
}
.info p {
    color: #ccc;
    margin-bottom: 15px;
}
.btn {
    display: inline-block;
    background: #7b3fdb;
    color: #fff;
    padding: 12px 28px;
    border-radius: 40px;
    text-decoration: none;
    transition: 0.3s;
}
.btn:hover {
    background: #9b5eff;
}
footer {
    padding: 20px;
    color: #555;
    font-size: 0.9rem;
}