ZomerActie

HTML

<div id="container">
    <img id="competitie" src="https://i.imgur.com/ZIPPGk1.png" alt="Competitie">

    <div id="buttons">
        <a class="summer-btn"
           href="https://virtualpopstar.com/social/forum?category=11&topic=994886" target="_blank">
            Topic met informatie<br>KLIK
        </a>


    </div>

    <div id="curtain-left" class="curtain"></div>
    <div id="curtain-right" class="curtain"></div>
</div>

CSS

html, body {
    margin: 0;
    padding: 0;
    background: transparent;
    overflow: hidden;
}

#container {
    position: relative;
    width: 688px;
    height: 500px;
    margin: 0 auto;
    overflow: hidden;
}

#container::after {
    content: "";
    position: absolute;
    top: 0;
    left: -150%;
    width: 50%;
    height: 100%;
    background: rgba(255,255,255,0.12);
    transform: skewX(-25deg);
    animation: sunbeam 10s infinite;
    pointer-events: none;
    z-index: 4;
}

#competitie {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

#buttons {
    position: absolute;
    bottom: 105px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 20px;
    z-index: 5;
    opacity: 0;
    animation: showButtons 1s forwards;
    animation-delay: 4s;
}

.summer-btn {
    width: 230px;
    padding: 10px 8px;
    background: #f7f1e3;
    border: 4px solid #9fc8cb;
    border-radius: 18px;
    color: #005b8f;
    text-decoration: none;
    text-align: center;
    font-family: Arial, sans-serif;
    font-size: 18px;
    font-weight: bold;
    box-shadow:
        0 4px 10px rgba(0,0,0,0.15),
        0 0 15px rgba(255,255,255,0.25);
    position: relative;
    overflow: hidden;
    animation: float 3s ease-in-out infinite;
}

.summer-btn:hover {
    transform: scale(1.08) rotate(3deg);
}

.summer-btn::before {
    content: "";
    position: absolute;
    top: 0;
    left: -120%;
    width: 60%;
    height: 100%;
    background: rgba(255,255,255,.45);
    transform: skewX(-25deg);
    animation: shine 4s infinite;
}

@keyframes float {
    0% {
        transform: translateY(0px) rotate(-1deg);
    }
    50% {
        transform: translateY(-6px) rotate(1deg);
    }
    100% {
        transform: translateY(0px) rotate(-1deg);
    }
}

@keyframes shine {
    0% {
  ...

JavaScript

window.addEventListener("load", () => {
    setTimeout(() => {
        document.getElementById("container").classList.add("open");
    }, 1000);
});