body {
    background-image:
        linear-gradient(135deg, rgba(255,232,214,0.88) 0%, rgba(255,241,230,0.88) 50%, rgba(255,214,204,0.88) 100%),
        url('../images/birthday-cake.png');
    background-repeat: no-repeat, repeat;
    background-size: cover, 160px 160px;
    min-height: 100vh;
}

h1.display-5 {
    text-align: center;
    color: #d85a30;
    text-shadow: 2px 2px 6px rgba(0, 0, 0, 0.15);
    letter-spacing: 1px;
    margin-top: 2rem;
}