Redesign post cards on frontpage

• Use default font instead of Hermann
• Reduce size by removing the image and some metainformation

Relates to #47 (closed) and !46 (closed)

_includes/cards/post_card.html

@@ -5,17 +5,31 @@ Parameters:
 post: The post which sould be displayed on the card
 
 {%- endcomment -%}
-
-<div class="card {{ include.class }} bg-light">
-    <div class="card-header">
-        <span class="badge badge-secondary">
-            <i class="fas fa-calendar-day" aria-hidden="true"></i>
-            {{ include.post.data | date: "%d.&thinsp;%b.&thinsp;%y" }}
-        </span>
-    </div>
-    <div class="card-body">
-        <a href="{{ include.post.url | relative_url }}" class="stretched-link">
-            <h4 class="card-title">{{ include.post.title }}</h4>
-        </a>
+{%- if include.post.title_image == "default" %}
+{%- assign img_url = site.directory.images
+    | append: 'HIFIS_LOGO_news_cards_equal.svg'
+    | strip 
+    | relative_url -%}
+{%- else -%}
+{%- assign img_url = site.directory.large_images
+    | append: "phone/"
+    | append: include.post.title_image
+    | strip 
+    | relative_url -%}
+{%- endif -%}
+<div class="card image-card bg-primary">
+    <img src="{{ img_url }}" class="card-img" alt="Title image for {{ post.title }}">
+    <div class="card-img-overlay">
+        <div class="card-title">
+            <span class="badge badge-secondary">
+                <i class="fas fa-calendar-day" aria-hidden="true"></i>
+                {{ include.post.data | date: "%d.&thinsp;%b.&thinsp;%y" }}
+            </span>
+        </div>
+        <div class="card-text">
+            <a href="{{ include.post.url | relative_url }}" class="stretched-link">
+                <h4>{{ include.post.title }}</h4>
+            </a>
+        </div>
     </div>
 </div>