body {
    position: relative;
    background-image: url('background.jpeg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    background-repeat: no-repeat;
    z-index: 0;
}

body::before {
    content: '';
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(15, 23, 42, 0.45);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    z-index: -1;
}

.glass-card {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(25px);
    -webkit-backdrop-filter: blur(25px);
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-shelf {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 0.5s cubic-bezier(0.4, 0, 0.2, 1), 
                opacity 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-shelf.open {
    max-height: 220px;
    opacity: 1;
}

/* Tip Button Glass Treatment */
.tip-button {
    background: rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: 0 4px 12px 0 rgba(0, 0, 0, 0.15);
}

.tip-button:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-1px);
}