.box_hallow {
    position: relative;
  overflow: hidden;
   width: 500px;
   height: 1400px;
   margin: auto;
}

.boxlink a:link {
    color: black;
}
.boxlink a:visited {
    color: black;
}
.boxlink a:hoover {
    color: white;
}
.box_hallow h1 {
  text-align: center;
    position: relative;
    z-index: 2;
  color: black;
}
.box_hallow h2 {
    padding: 15px;
    text-align: center;
    position: relative;
    z-index: 2;
  color: black;
font-size: 18px;
    top: -65px;
}
.box_hallow h3 {
    text-align: center;
    position: relative;
    z-index: 2;
    color: black;
    font-size: 18px;
    top: -125px;
}
.box_inhalt {
    margin-left: 15px;
  margin-right:15px;
  text-align: justify;
    position: relative;
    z-index: 2;
  color: black;
top: -120px;
}
/* You could use :after - it doesn't really matter */
.box_hallow:before {
    content: ' ';
    display: block;
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    opacity: 0.3;
    background-image: url(https://www.buffymagazin.de/wikinger/images/greeniceland/post_bg2.png);
    background-repeat: no-repeat;
    background-position: 50% 0;
    /*background-size: cover;*/
}

.begriff {
    color: var(--farbe4);
text-transform: uppercase; 
    font-size: 12px;
   margin-left: 15px;

    border-bottom: 1px solid var(--farbe4);
        padding-bottom: 3px;
    padding-top: 5px;
  margin-bottom: 50px;
  position: relative;
  bottom: -50px;
font-weight: bold;
}