Some cosmetic improvements in the documentation.

docs/course/visual_perception.md

@@ -1,12 +1,10 @@
-## Color Perception
-:octicons-info-24: Informative 
+## Color Perception :material-alert-decagram:{ .mdx-pulse title="Too important!" }
+:octicons-info-24: Informative ·
+:octicons-beaker-24: Practical
 
 We can establish an understanding on color perception through studying its physical and perceptual meaning.
 This way, we can gather more information on its relation to technologies and devices including displays, cameras, sensors, communication devices, computers and computer graphics.
 
-### What is Color?
-:octicons-info-24: Informative 
-
 Color, a perceptual phenomenon, can be explained in a physical and visual perception capacity.
 In the physical sense, color is a quantity representing the response to wavelength of light.
 The human visual system can perceive colors within a certain range of the electromagnetic spectrum, from around 400 nanometers to 700 nanometers.
@@ -118,3 +116,13 @@ TODO: add some more stuff here
 As we dive deeper into light and color perception, it becomes evident that the task of replicating the natural spectrum of colors in technology is still an evolving journey. This exploration into the nature of color sets the stage for a deeper examination of how our biological systems perceive color and how technology strives to emulate that perception.
 
 -->
+
+??? tip end "Consider revisiting this chapter"
+    Remember that you can always revisit this chapter as you progress with the course and as you need it.
+    This chapter is vital for establishing a means to complete your assignments and could help formulate a suitable base to collaborate and work with [my research group](https://complightlab.com) in the future or other experts in the field.
+
+!!! warning end "Reminder"
+    We host a Slack group with more than 300 members.
+    This Slack group focuses on the topics of rendering, perception, displays and cameras.
+    The group is open to public and you can become a member by following [this link](https://complightlab.com/outreach/).
+    Readers can get in-touch with the wider community using this public group.

docs/index.md

@@ -1,31 +1,40 @@
 # Getting started
+:octicons-info-24: Informative
+
 Odak (pronounced "O-dac") is the fundamental library for scientific computing in optical sciences, computer graphics, and visual perception.
 We designed this page to help first-time users, new contributors, and existing users understand where to go within this documentation when they need help with certain aspects of Odak.
 If you think you need a refresher or are a beginner willing to learn more about light and computation, we created an entire course named `Computational Light` for you to get to pace with the computational aspects of light.
 
-[Source code](https://github.com/kaanaksit/odak){ .md-button .md-button--primary }
 
-## Absolute Beginners
-- [`Computational Light Course`](course/index.md)
+## Absolute Beginners :material-alert-decagram:{ .mdx-pulse title="Too important!" }
+:octicons-info-24: Informative ·
+:octicons-beaker-24: Practical
+
+[Learn Odak and Physics of Light: Computational Light Course](course/index.md){ .md-button .md-button--primary }
 
 ## New Users
+:octicons-info-24: Informative
 
 - [`What is Odak?`](beginning.md)
 - [`Installation`](installation.md)
 
 ## Use cases
+:octicons-info-24: Informative
 
 - [`Computer-generated holography`](cgh.md)
 - [`General toolkit`](toolkit.md)
 - [`Optical Raytracing`](raytracing.md)
 - [`Machine Learning`](machine_learning.md)
-- [`Visual perception`](perception.md)
+- [`Visual Perception`](perception.md)
+- [`Lensless Cameras`](lensless.md)
 
 ## New contributors
+:octicons-info-24: Informative
 
 - [`Contributing to Odak`](contributing.md)
 
 ## Additional information
+:octicons-info-24: Informative
 
 - [`Citing Odak in a scientific publication using Zenodo`](https://github.com/kaanaksit/odak#how-to-cite)
 - [`License of Odak`](https://github.com/kaanaksit/odak/blob/master/LICENSE.txt)

overrides/main.html

@@ -2,12 +2,13 @@
 
 {% block announce %}
 For updates follow 
-<a href="https://twitter.com/kaanaksit" style="color:#1da1f2;">
+<a href="https://x.com/kaanaksit" style="color:#1da1f2;">
 <strong>@kaanaksit</strong> 
 </a>
 on
-<a href="https://twitter.com/kaanaksit" style="color:#1da1f2;">
+<a href="https://x.com/kaanaksit" style="color:#1da1f2;">
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+<path d="M714.163 519.284L1160.89 0H1055.03L667.137 450.887L357.328 0H0L468.492 681.821L0 1226.37H105.866L515.491 750.218L842.672 1226.37H1200L714.137 519.284H714.163ZM569.165 687.828L521.697 619.934L144.011 79.6944H306.615L611.412 515.685L658.88 583.579L1055.08 1150.3H892.476L569.165 687.854V687.828Z" fill="white"/></path></svg>_</span>
 </a>
 <strong>
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