*{
    box-sizing: border-box;
}
body{
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    overflow: hidden;
    margin: 0;
}

.container{
    display: flex;
    width: 90vw;
}

.panel{
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    height: 80vh;
    border-radius: 50px;
    color: #fff;
    cursor: pointer;
    flex: 0.6;
    margin: 10px;
    position: relative;
    transition: flex 0.8s ease-in;
}

.panel h3{
    font-size: 25px;
    position: absolute;
    bottom: 20px;
    left: 20px;
    margin: 0;
    opacity: 0;
}

.panel.active{
    flex: 5;
}

.panel.active h3{
    opacity: 1;
    transition: opacity 0.6s ease-in 0.9s;
}