diff --git a/README.md b/README.md
index 0c2ae36..a380504 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,7 @@ This is a list of classless CSS themes and frameworks.  "Classless" means a styl
     + [Fylgja](#fylgja)
     + [Milligram](#milligram)
     + [mini.css](#minicss)
+    + [mono](#mono)
     + [Picnic CSS](#picnic-css)
     + [SASS-ZERO (Breadboard)](#sass-zero-breadboard)
     + [Wing](#wing)
@@ -683,6 +684,19 @@ These are frameworks that do not force you to apply their classes to many elemen
 [![minicss.png](thumbnail/minicss.png)](screenshot/minicss.png)
 
 
+### mono
+
+- [Repository](https://github.com/artalar/mono)
+  ![GitHub stars](https://img.shields.io/github/stars/artalar/mono?style=flat-square)
+  ![GitHub contributors](https://img.shields.io/github/contributors-anon/artalar/mono?style=flat-square)
+  ![Last commit](https://img.shields.io/github/last-commit/artalar/mono?style=flat-square)
+  ![GitHub open issues](https://img.shields.io/github/issues-raw/artalar/mono?style=flat-square)
+  ![GitHub closed issues](https://img.shields.io/github/issues-closed-raw/artalar/mono?style=flat-square)
+- [Demo](https://monocss.vercel.app/)
+
+[![mono.png](thumbnail/mono.png)](screenshot/mono.png)
+
+
 ### Picnic CSS
 
 Caution: Picnic CSS requires specific HTML structure to display certain elements. For example, it hides vanilla checkboxes and radio buttons. The structure serves as the effective class of the element. This means an existing project will have to modify its HTML markup for, e.g., every checkbox and radio button to start using Picnic.
diff --git a/data/projects.toml b/data/projects.toml
index 50cfa06..1ca78e2 100644
--- a/data/projects.toml
+++ b/data/projects.toml
@@ -409,6 +409,15 @@ website = ""
 screenshots = ["minicss.png"]
 tags = ["class-light"]
 
+[mono]
+demo = "https://monocss.vercel.app/"
+github = "artalar/mono"
+note = ""
+website = ""
+screenshots = ["mono.png"]
+tags = ["class-light"]
+
+
 ["Picnic CSS"]
 demo = "http://picnicss.com/"
 github = "franciscop/picnic"
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