Output not corresponding with CSS rules

Hey,
please have a look at the URL in private field in screensizes between 480 und 767px.
Watch the size of the header.
Inspector says 20px but there is no rule in the CSS that says 20 – it says 14.
Why is that and how can i fix that?

Kind regards
Chris

Here is the actual CSS:

/*Shop*/
.product p.wc-gzd-additional-info {
	display: none !important;
}
#top .onsale {
	border-radius: 6px !important;
	padding: 0 5px !important;
}
.products .product h2, .products .product h3, .products .product h4, .products .product h5, .products .product h6, h2.woocommerce-loop-product__title {
	font-size: 1.5em !important;}
.beschreibinliste {
	font-size: 11px !important;
	line-height: 13px !important;
	margin: 0 0 36px 0!important;
}
.inner_product div {
	line-height: 11px;
	font-size: 11px;
	color: #7B7B7B;}

#top .avia_cart_buttons .button {
	background-color: #2d5c88 !important;
	color: #ffffff !important;}

ul.products li strong {
	display: inline !important;
}

/*ALLGEMEIN*/

.weiterethemen{font-size: 17px !important;
font-weight: bold !important;}
#top .aviaccordion-preview-title h3 {
	color: #fff !important;
	font-size: 14px !important;}

/*SLIDER*/
.slidedescfirst {
	/*Im ersten Slide auf startseite ist eine erste zeile die hervorgehoben werden soll*/
	font-weight: bold !important;
	font-size: 22px !important;
	line-height: 1.5em !important;}
.caption_framed .slideshow_caption .avia-caption-title, .caption_framed .slideshow_caption .avia-caption-content p {
  margin: 0 !important;}
.avia_transform .av_slideshow_full .avia-caption-title {
	color: #ffffff !important;}

.responsive #top .slideshow_caption .avia-caption-content {
	
	text-align: left !important;
	hyphens: auto !important;
}

.angebotslider .avia-caption-title {
	font-size: 29px !important;}
.angebotslider .avia-caption-content {
	line-height: 1.3em;
	font-size: 13px !important;
	text-align: left !important;
	hyphens: auto !important;}
#zeitgestaltung .slideshow_caption {
	width: 64%;}
	
/*##### SEITEN ######*/
/*ANGEBOTE & CHILDPAGES*/
.cc-child-pages-thumb {
  margin: 11px 15px 9px 13px !important;
  float: none;
  padding: 8px;
  background: #fff;
  border: 1px solid #efefef;
  border-radius: 5px;
  box-shadow: 3px 4px 3px #efefef;}
.ccchildpages {
	border: 1px solid #ccc;
	border-radius: 5px;
	box-shadow: 4px 4px 5px #cccccc;
	background-repeat: repeat;}
.ccchildpage h3 {
	font-size:15px !important;}
.ccchildpage {
	background: #fafafa;
	border: 1px solid #ccc;
	border-radius: 5px;
	box-shadow: 4px 4px 5px #cccccc;
	min-height: 510px !important;
	position:relative;}
.ccpages_more a {
	font-size: 100%;
	border: 10px solid #c05f5f !important;
	background: #c05f5f;
	color: #ffffff !important;
	font-weight: bold !important;
	border-radius: 7px;
	position: absolute;
	bottom: 15px;}

/* #Media Queries
================================================== */

	/* kleiner als 990 (devices and browsers) */
	@media only screen and (max-width: 989px) {
		 #full_slider_1, 
  #full_slider_1 .av_slideshow_full.avia-slideshow,
  #full_slider_1  .avia-slideshow-inner,
  #full_slider_1 .avia-slideshow li,
  #full_slider_1 .avia-slideshow li img {
    min-height: 240px;}
  #full_slider_1 .avia-slideshow li img {
    width: 140% !important;
    max-width: auto;}
   .html_header_transparency #top .avia-builder-el-0 .slideshow_caption {
      padding-top: 0px;}
.angebotslider .avia-caption-title {
	font-size: 22px !important;}
.angebotslider .avia-caption-content {
	line-height: 1.25em;
	font-size: 12px !important;}
}

	/* zwischen 768 und 990 Tablet Portrait (devices and browsers) */
	@media only screen and (min-width: 768px) and (max-width: 989px) {
.ccchildpage {
	min-height: 450px !important;}	
#zeitgestaltung .slideshow_caption {
	width: 64%;}
.angebotslider .avia-caption-title {
	font-size: 18px !important;}
.angebotslider .avia-caption-content {
	line-height: 1.25em;
	font-size: 12px !important;}

}
			

	/* kleiner als 768 */
	@media only screen and (max-width: 767px) {

	 	}

	/* zwischen 768 und 480 */
	@media only screen and (min-width: 480px) and (max-width: 767px) {
.ccchildpage {
	min-height: 550px !important;}	
.cc-child-pages-thumb {
  margin:11px 7px 9px 0px !important;
  padding: 5px;}
		#startseite .av_slideshow_full .container.caption_container {
	top: 0px !important;
	height: 55% !important;}
		.angebotslider .avia-caption-title {
	font-size: 14px !important;}
.angebotslider .avia-caption-content {
	line-height: 1.15em;
	font-size: 11px !important;}
	}

	/* zwischen 480 und 319 */
	@media only screen and (min-width: 319px) and (max-width: 480px) {
.ccchildpage {
	min-height: 405px !important;}
.cc-child-pages-thumb {
  margin: 11px 0px 9px 0px !important;
  padding: 5px;}

.responsive #top .slideshow_caption .avia-caption-content {
	text-align: left !important;
	hyphens: auto !important;
	font-size: 12px !important;
	line-height: 1.2em !important;
}
.responsive #top .slideshow_caption h2 {
	font-size: 16px !important;}
#startseite .av_slideshow_full .container.caption_container {
	top: 0px !important;
	height: 55% !important;}
		
	}
	
	/* kleiner als 319 */
	@media only screen and (max-width: 319px) {
.ccchildpage {
	min-height: 350px !important;}
.cc-child-pages-thumb {
  margin: 11px 0px 9px 0px !important;
  padding: 5px;}
		

.responsive #top .slideshow_caption .avia-caption-content {
	text-align: left !important;
	hyphens: auto !important;
	font-size: 11px !important;
	line-height: 1.1em !important;
}
.responsive #top .slideshow_caption h2 {
	font-size: 14px !important;
}