DOCSP-15452: update landing page with new copy (#76)

Author: schmalliso

source/index.txt

@@ -19,24 +19,22 @@ Welcome to the MongoDB Documentation
    :layout: carousel
 
    .. card::
-      :headline: Run a self-managed database
+      :headline: Use MongoDB
       :cta: Get started with MongoDB Server
       :url: https://docs.mongodb.com/manual/tutorial/getting-started/
       :icon: /images/icons/server.svg
       :icon-alt: MongoDB Server icon
 
-      Download and install the MongoDB database on your own
-      infrastructure.
+      Learn fundamental skills including query, aggregation, and sharding.
 
    .. card::
-      :headline: Run MongoDB in the cloud
+      :headline: Deploy with MongoDB Atlas
       :cta: Get started with MongoDB Atlas
       :url: https://docs.atlas.mongodb.com/getting-started/
       :icon: /images/icons/atlas.svg
       :icon-alt: MongoDB Atlas icon
 
-      Work with your data in a fully-managed database on AWS, Azure, and
-      GCP.
+      Start for free with MongoDB on AWS, Google Cloud, and Azure.
 
    .. card::
       :headline: Connect your application
@@ -58,7 +56,7 @@ Welcome to the MongoDB Documentation
       GUI.
 
    .. card::
-      :headline: Create visual representations
+      :headline: Create data visualizations
       :cta: Get started with MongoDB Charts
       :url: https://docs.mongodb.com/charts/saas/tutorial/movie-details/movie-details-tutorial-overview/
       :icon: /images/icons/charts.svg
@@ -67,14 +65,13 @@ Welcome to the MongoDB Documentation
       Create charts and live dashboards to reveal data trends.
 
    .. card::
-      :headline: Build a serverless application
+      :headline: Build a mobile or web app
       :cta: Get started with MongoDB Realm
       :url: https://docs.mongodb.com/realm/
       :icon: /images/icons/realm.svg
       :icon-alt: MongoDB Realm icon
 
-      Create an application quickly with no need to set up server
-      infrastructure.
+      Build cross-platform apps with local persistence and backend sync.
 
 Learn through examples and best practices
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