Changing picture height

I am using PORTAFOLIO by WPEXPLORER. I set it to display 2 pictures next to each other. However I do not like the height of the pictures. But I can’t seem to change that at all. http://fotografie.whenlovefalls.com/

/*percent grid*/
.span_2_of_2{width:100%; height:50%;}.span_1_of_2{width:49.2%; height:30%;}.span_3_of_3{width:100%}.span_2_of_3{width:66.1%}.span_1_of_3{width:32.2%}.span_4_of_4{width:100%}.span_3_of_4{width:74.6%}.span_2_of_4{width:49.2%}.span_1_of_4{width:23.8%}.span_5_of_5{width:100%}.span_4_of_5{width:79.68%}.span_3_of_5{width:59.36%}.span_2_of_5{width:39.04%}.span_1_of_5{width:18.72%}.span_6_of_6{width:100%}.span_5_of_6{width:83.06%}.span_4_of_6{width:66.13%}.span_3_of_6{width:49.2%}.span_2_of_6{width:32.26%}.span_1_of_6{width:15.33%}.span_7_of_7{width:100%}.span_6_of_7{width:85.48%}.span_5_of_7{width:70.97%}.span_4_of_7{width:56.45%}.span_3_of_7{width:41.92%}.span_2_of_7{width:27.42%}.span_1_of_7{width:12.91%}.span_8_of_8{width:100%}.span_7_of_8{width:87.3%}.span_6_of_8{width:74.6%}.span_5_of_8{width:61.9%}.span_4_of_8{width:49.2%}.span_3_of_8{width:36.5%}.span_2_of_8{width:23.8%}.span_1_of_8{width:11.1%}.span_9_of_9{width:100%}.span_8_of_9{width:88.71%}.span_7_of_9{width:77.42%}.span_6_of_9{width:66.13%}.span_5_of_9{width:54.84%}.span_4_of_9{width:43.55%}.span_3_of_9{width:32.26%}.span_2_of_9{width:20.97%}.span_1_of_9{width:9.68%}.span_10_of_10{width:100%}.span_9_of_10{width:89.84%}.span_8_of_10{width:79.68%}.span_7_of_10{width:69.52%}.span_6_of_10{width:59.36%}.span_5_of_10{width:49.2%}.span_4_of_10{width:39.04%}.span_3_of_10{width:28.88%}.span_2_of_10{width:18.72%}.span_1_of_10{width:8.56%}.span_11_of_11{width:100%}.span_10_of_11{width:90.7%}.span_9_of_11{width:81.47%}.span_8_of_11{width:72.24%}.span_7_of_11{width:63.01%}.span_6_of_11{width:53.78%}.span_5_of_11{width:44.55%}.span_4_of_11{width:35.32%}.span_3_of_11{width:26.09%}.span_2_of_11{width:16.86%}.span_1_of_11{width:7.63%}.span_12_of_12{width:100%}.span_11_of_12{width:91.46%}.span_10_of_12{width:83%}.span_9_of_12{width:74.54%}.span_8_of_12{width:66.08%}.span_7_of_12{width:57.62%}.span_6_of_12{width:49.16%}.span_5_of_12{width:40.7%}.span_4_of_12{width:32.24%}.span_3_of_12{width:23.78%}.span_2_of_12{width:15.32%}.span_1_of_12{width:6.86%}

I can add a height there but it won’t change anything.

.portfolio-entry-link img { display: block; width: 100%; height: 30%;}

Same here. It seems the widh determinants how big the picture should be. And while I don’t want the aspect radio the screwed is there anyway to cut the picture of so the height is smaller?