[enh] better highlighting

searx/static/css/style.css

 .right{float:right}
 .invisible{display:none}
 .left{float:left}
+.highlight{color:#094089}
+.content .highlight{color:#000}
 .image_result{float:left;margin:10px 10px;position:relative;height:160px}.image_result img{border:0;height:160px}
 .image_result p{margin:0;padding:0}.image_result p span a{display:none;color:#fff}
 .image_result p:hover span a{display:block;position:absolute;bottom:0;right:0;padding:4px;background-color:rgba(0,0,0,0.6);font-size:.7em}

searx/static/less/definitions.less

 @color-base: #3498DB;
 @color-base-dark: #2980B9;
 @color-base-light: #ECF0F1;
-
+@color-highlight: #094089;
+@color-black: #000000;
 
 /// General
 

searx/static/less/style.less

 	float: left;
 }
 
+.highlight {
+    color: @color-highlight;
+}
+
+.content .highlight {
+    color: @color-black;
+}
+
 .image_result {
 	float: left;
 	margin: 10px 10px;

searx/utils.py

     query = query.decode('utf-8')
     if content.lower().find(query.lower()) > -1:
         query_regex = u'({0})'.format(re.escape(query))
-        content = re.sub(query_regex, '<b>\\1</b>', content, flags=re.I | re.U)
+        content = re.sub(query_regex, '<span class="highlight">\\1</span>', content, flags=re.I | re.U)
     else:
         regex_parts = []
         for chunk in query.split():
             else:
                 regex_parts.append(u'{0}'.format(re.escape(chunk)))
         query_regex = u'({0})'.format('|'.join(regex_parts))
-        content = re.sub(query_regex, '<b>\\1</b>', content, flags=re.I | re.U)
+        content = re.sub(query_regex, '<span class="highlight">\\1</span>', content, flags=re.I | re.U)
 
     return content