.birthday-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: 9999;
    overflow: hidden;
    contain: strict;
}

.birthday-garland {
    position: absolute;
    top: -1vh;
    left: 0;
    width: 100vw;
    z-index: 55;
    pointer-events: none;
    /* optional: a little drop shadow for depth */
    filter: drop-shadow(0 5px 8px rgba(0,0,0,0.5));
}

.birthday-garland img {
    width: 100%;
    height: auto;
    object-fit: cover;
}

.birthday-cake {
    position: absolute;
    bottom: 2vh;
    left: 50vw;
    transform: translateX(-50%);
    font-size: 8rem;
    z-index: 50;
    filter: drop-shadow(0 0 10px rgba(255,255,255,0.4));
    pointer-events: auto;
}

.birthday-cake img {
    height: 15vh;
    width: auto;
    object-fit: contain;
    max-height: 150px;
}

.birthday-symbol {
    position: absolute;
    bottom: -10vh; /* balloons rise from bottom */
    animation: birthday-rise linear infinite;
    font-size: 3rem;
    opacity: 0.95;
    z-index: 40;
    pointer-events: none; /* Container itself should not block clicks */
}

.birthday-inner {
    pointer-events: auto; /* Allow hover over the actual item */
    cursor: crosshair;
    display: inline-block;
}

.birthday-symbol img {
    width: 6vh;
    height: auto;
    max-width: 60px;
    object-fit: contain;
}

.birthday-confetti {
    position: absolute;
    top: -5vh;
    width: 10px;
    height: 10px;
    opacity: 0.9;
    animation: birthday-confetti-fall linear infinite;
    z-index: 30;
    /* Mix of circles and squares by using CSS variables or random in JS. For simplicity, we make all slightly rounded rectangles */
    border-radius: 2px;
}

@keyframes birthday-rise {
    0% { 
        transform: translateY(10vh) rotate(var(--start-rot, 0deg)); 
        opacity: 0; 
    }
    10% { 
        opacity: 1; 
    }
    90% {
        opacity: 1;
    }
    100% { 
        transform: translateY(-110vh) rotate(calc(var(--start-rot, 0deg) * -1)); 
        opacity: 0; 
    }
}

@keyframes birthday-confetti-fall {
    0% {
        transform: translateY(-5vh) rotateX(0deg) rotateY(0deg) rotateZ(0deg);
        opacity: 0;
    }
    5% {
        opacity: 1;
    }
    90% {
        opacity: 1;
    }
    100% {
        transform: translateY(105vh) rotateX(720deg) rotateY(360deg) rotateZ(180deg);
        opacity: 0;
    }
}

@keyframes birthday-sway {
    0% { transform: rotate(-8deg) translateX(-5%); }
    100% { transform: rotate(8deg) translateX(5%); }
}

@keyframes birthday-pop {
    0% { transform: scale(1); opacity: 1; filter: brightness(1); }
    30% { transform: scale(1.3); opacity: 1; filter: brightness(1.5); }
    100% { transform: scale(0); opacity: 0; filter: brightness(2); }
}

.birthday-burst-confetti {
    position: absolute;
    pointer-events: none;
    z-index: 1000;
    will-change: transform, opacity;
    animation: birthday-burst-fall 1.5s cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards;
}

.birthday-burst-confetti.circle {
    border-radius: 50%;
}

.birthday-burst-confetti.triangle {
    width: 0;
    height: 0;
    background-color: transparent !important;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-bottom: 10px solid var(--shape-color, #ff0000);
}

@keyframes birthday-burst-fall {
    0% {
        transform: translate(0, 0) rotate3d(var(--rx), var(--ry), var(--rz), 0deg);
        opacity: 1;
    }
    30% {
        transform: translate(var(--burst-x), var(--burst-y)) rotate3d(var(--rx), var(--ry), var(--rz), calc(var(--rot-dir) * 0.3));
        opacity: 1;
    }
    100% {
        transform: translate(var(--burst-x), calc(var(--burst-y) + 150px)) rotate3d(var(--rx), var(--ry), var(--rz), var(--rot-dir));
        opacity: 0;
    }
}