[Doc] Use cards for Examples landing page

doc/sphinx/examples/index.md

@@ -5,9 +5,91 @@ particular programming language, select the corresponding category below. Or, to
 all examples covering a particular topic, regardless of programming language, select
 from the {ref}`list of example tags <tagoverview>`.
 
+## Python Examples
+
+````{grid} 2 2 2 3
+:gutter: 3
+
+```{grid-item-card} Thermodynamics
+:link: python/thermo/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Kinetics
+:link: python/kinetics/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Transport
+:link: python/transport/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Reactor networks
+:link: python/reactors/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} 1D reacting flows
+:link: python/onedim/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Surface chemistry
+:link: python/surface_chemistry/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Multiphase
+:link: python/multiphase/index
+:link-type: doc
+:text-align: center
+```
+
+````
+
+## Examples in Other Languages
+
+````{grid} 2 2 3 3
+:gutter: 3
+
+```{grid-item-card} C++
+:link: cxx/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} C
+:link: clib/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Matlab (experimental)
+:link: matlab_experimental/index
+:link-type: doc
+:text-align: center
+```
+
+```{grid-item-card} Fortran
+:link: fortran/index
+:link-type: doc
+:text-align: center
+```
+
+
+````
+
 % The following pages are generated by sphinx-gallery
 ```{toctree}
 :maxdepth: 2
+:hidden:
 
 python/index
 cxx/index
@@ -19,6 +101,7 @@ fortran/index
 % The following page is generated by sphinx-tags
 ```{toctree}
 :maxdepth: 1
+:hidden:
 
 /_tags/tagsindex
 ```