optmize documentation layout

doc/doxyfile.in

@@ -1413,7 +1413,7 @@ ECLIPSE_DOC_ID         = org.doxygen.Project
 # The default value is: NO.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-DISABLE_INDEX          = YES
+DISABLE_INDEX          = NO
 
 # The GENERATE_TREEVIEW tag is used to specify whether a tree-like index
 # structure should be generated to display hierarchical information. If the tag

doc/style.css

@@ -14,3 +14,25 @@
   padding: 1ex;
   margin: 0;
 }
+img, object {
+  max-width: 100% !important;
+}
+@media (max-width: 50em) {
+  #navrow1, #navrow2 {
+    display: block
+  }
+  #side-nav, #splitbar, .ui-resizable-handle ui-resizable-e, .ui-resizable-handle ui-resizable-s {
+    display: none;
+  }
+  #doc-content {
+    margin-left: 0 !important;
+  }
+}
+@media (min-width: 50em) {
+  #navrow1, #navrow2 {
+    display: none;
+  }
+  #side-nav, #splitbar, .ui-resizable-handle ui-resizable-e, .ui-resizable-handle ui-resizable-s {
+    display: block
+  }
+}