diff --git a/c3l_membership/static/style.css b/c3l_membership/static/style.css
--- a/c3l_membership/static/style.css
+++ b/c3l_membership/static/style.css
@@ -19,3 +19,18 @@ p {
   text-align: right;
   padding-bottom: 1rem;
 }
+
+.form-error {
+  background: #f98691;
+  border: 1px solid #dc3545;
+  border-radius: 4px;
+  padding: 0.5em 0.6em;
+  font-weight: 550;
+  color: #3d0309;
+}
+
+.field-error {
+  background: #f98691;
+  border: 1px solid #dc3545;
+  color: #3d0309;
+}
diff --git a/c3l_membership/templates/index.html b/c3l_membership/templates/index.html
--- a/c3l_membership/templates/index.html
+++ b/c3l_membership/templates/index.html
@@ -43,7 +43,7 @@
         {% if form.errors %}
           {% for fieldname, errors in form.errors.items() %}
             {% for error in errors %}
-              <p>{{ fieldname }} - {{ error }}</p>
+              <p class="form-error">{{ fieldname }} - {{ error }}</p>
             {% endfor %}
           {% endfor %}
         {% endif %}
@@ -54,19 +54,19 @@
             <div class="pure-g">
               <div class="pure-u-1-1">
                 <b>{{ form.username.label }}</b>
-                {{ form.username(required=True, class="pure-u-1-1") }}
+                {{ form.username(required=True, class="pure-u-1-1 field-error" if form.username.errors else "pure-u-1-1") }}
               </div>
             </div>
             <div class="pure-g">
               <div class="pure-u-1-1">
                 <b>{{ form.email.label }}</b>
-                {{ form.email(required=True, class="pure-u-1-1") }}
+                {{ form.email(required=True, class="pure-u-1-1 field-error" if form.email.errors else "pure-u-1-1") }}
               </div>
             </div>
             <div class="pure-g">
               <div class="pure-u-1-1">
                 <b>{{ form.fullname.label }}</b>
-                {{ form.fullname(required=True, class="pure-u-1-1") }}
+                {{ form.fullname(required=True, class="pure-u-1-1 field-error" if form.fullname.errors else "pure-u-1-1") }}
               </div>
             </div>
             <div class="pure-g">
@@ -123,37 +123,37 @@
                 <div class="pure-g">
                   <div class="pure-u-1-1">
                     <b>{{ form.birthday.label }}</b>
-                    {{ form.birthday(class="pure-u-1-1") }}
+                    {{ form.birthday(class="pure-u-1-1 field-error" if form.birthday.errors else "pure-u-1-1") }}
                   </div>
                 </div>
                 <div class="pure-g">
                   <div class="pure-u-1-1">
                     <b>{{ form.street.label }}</b>
-                    {{ form.street(class="pure-u-1-1") }}
+                    {{ form.street(class="pure-u-1-1 field-error" if form.street.errors else "pure-u-1-1") }}
                   </div>
                 </div>
                 <div class="pure-g">
                   <div class="pure-u-1-1">
                     <b>{{ form.zip.label }}</b>
-                    {{ form.zip(class="pure-u-1-1") }}
+                    {{ form.zip(class="pure-u-1-1 field-error" if form.zip.errors else "pure-u-1-1") }}
                   </div>
                 </div>
                 <div class="pure-g">
                   <div class="pure-u-1-1">
                     <b>{{ form.city.label }}</b>
-                    {{ form.city(class="pure-u-1-1") }}
+                    {{ form.city(class="pure-u-1-1 field-error" if form.city.errors else "pure-u-1-1") }}
                   </div>
                 </div>
                 <div class="pure-g">
                   <div class="pure-u-1-1">
                     <b>{{ form.state.label }}</b>
-                    {{ form.state(class="pure-u-1-1") }}
+                    {{ form.state(class="pure-u-1-1 field-error" if form.state.errors else "pure-u-1-1") }}
                   </div>
                 </div>
                 <div class="pure-g">
                   <div class="pure-u-1-1">
                     <b>{{ form.country.label }}</b>
-                    {{ form.country(class="pure-u-1-1") }}
+                    {{ form.country(class="pure-u-1-1 field-error" if form.country.errors else "pure-u-1-1") }}
                   </div>
                 </div>
                 <legend></legend>