Accessibility improvements (#53)

* add alt tags to lear more

* make logo section better screenreadable

* enhance contrast on footer

* add alt text to back button

* switch colors -> maybe better contrast on links?

* make link text better readable

* switch color back

* and another try

* Revert "and another try"

This reverts commit cb58c92c51.

tailwind.config.js

@@ -4,13 +4,13 @@ module.exports = {
     purge: {
         enabled: true,
         content: ['./**/*.html'],
-      },
+    },
     darkMode: 'media',
     theme: {
         extend: {
             colors: {
-              'primary':'#90A8D8',
-              'secondary':'#DDBC91',
+                'primary': '#90A8D8',
+                'secondary': '#DDBC91',
             },
             screens: {
                 'xs': '470px',
@@ -21,4 +21,4 @@ module.exports = {
     plugins: [
         require('@tailwindcss/typography'),
     ],
-}
+}