diff --git a/core/core.php b/core/core.php
index 5e12f93e..2cdf6cf1 100644
--- a/core/core.php
+++ b/core/core.php
@@ -1222,8 +1222,12 @@ class core extends common {
 				}
 			}
 			$css .= 'header{background-size:' . $this->getData(['theme','header','imageContainer']).'}';
-			$css .= 'header{background-color:' . $colors['normal'] . ';height:' . $this->getData(['theme', 'header', 'height']) . ';line-height:' . $this->getData(['theme', 'header', 'height']) . ';text-align:' . $this->getData(['theme', 'header', 'textAlign']) . '}';
-			$css .= '@media (max-width: 767px) {header{height:' . $this->getData(['theme', 'header', 'height'])/2 . 'px;line-height:' . $this->getData(['theme', 'header', 'height'])/2 . 'px;}}';
+			$css .= 'header{background-color:' . $colors['normal'] . ';height:' . $this->getData(['theme', 'header', 'height']) . ';line-height:' . $this->getData(['theme', 'header', 'height']) . ';text-align:' . $this->getData(['theme', 'header', 'textAlign']) . '}';			
+			$css .= '@media (max-width: 767px) {header{height:' .
+					 str_replace("px","",$this->getData(['theme', 'header', 'height']))/2 . 
+					 'px;line-height:' . 
+					 str_replace("px","",$this->getData(['theme', 'header', 'height']))/2 . 
+					 'px;}}';
 			if($themeHeaderImage = $this->getData(['theme', 'header', 'image'])) {
 				$css .= 'header{background-image:url("../file/source/' . $themeHeaderImage . '");background-position:' . $this->getData(['theme', 'header', 'imagePosition']) . ';background-repeat:' . $this->getData(['theme', 'header', 'imageRepeat']) . '}';
 			}