Update learn pages (#59)

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docs/build/getting-started/networks/overview.md

@@ -4,7 +4,7 @@ The Darwinia ecosystem consists of four official long-term networks:
 
 |               Chain               |                                                                        Introduction                                                                         |
 | :-------------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------------------: |
-| [Darwinia](./darwinia.md) |                                EVM-compatible blockchain using the Substrate framework, featuring cross-chain capabilities.                                 |
-|     [Crab](./crab.md)     |                              Canary network for Darwinia, similar to Kusama for Polkadot, designed to expect and handle chaos.                              |
-| [Pangolin](./pangolin.md) |                          Primary test network for Darwinia, maintained to rigorously test new features before mainnet deployment.                           |
-|   [Rollup](./rollup.md)   | Partnership with AltLayer to develop an advanced Ethereum Op Stack rollup testnet, supported by Avail DA, showcasing cutting-edge blockchain data services. |
+| **[Darwinia](./darwinia.md)** |                                EVM-compatible blockchain using the Substrate framework, featuring cross-chain capabilities.                                 |
+|     **[Crab](./crab.md)**     |                              Canary network for Darwinia, similar to Kusama for Polkadot, designed to expect and handle chaos.                              |
+| **[Pangolin](./pangolin.md)** |                          Primary test network for Darwinia, maintained to rigorously test new features before mainnet deployment.                           |
+|   **[Rollup](./rollup.md)**   | Partnership with AltLayer to develop an advanced Ethereum Op Stack rollup testnet, supported by Avail DA, showcasing cutting-edge blockchain data services. |

docs/index.md

@@ -1,6 +1,20 @@
 
+# What is Darwinia?
+
 ![home](./images/home.png)
 
-# Powering Your DApp’s Cross-Chain Capabilities
+Darwinia is pioneering the development of cutting-edge cross-chain service solutions, with a strategic emphasis on boosting the cross-chain functionalities of decentralized applications. At its core, [the Darwinia Chains](./build/getting-started/networks/overview.md) represents an EVM-compliant network built upon [the Polkadot framework](https://polkadot.network/). It has been designed to integrate seamlessly with various bridge tools, such as [the Helix Bridge](https://helixbridge.app/) and [the MsgPort protocol](https://docs.msgport.xyz/). This integration facilitates the connection between assets within the Polkadot ecosystem and the wider array of EVM chains present in the Ethereum ecosystem.
+
+## Key Features
+
+### Cross-Chain Capabilities
+
+The Darwinia network serves as a bridge between the Polkadot ecosystem and the Ethereum ecosystem, unlocking a wide range of cross-chain capabilities between the two blockchain ecosystems. For example, it enables the connection of Polkadot's AssetHub with a broader array of EVM chains. Moreover, the Darwinia network is poised to be the first place for the development of innovative cross-chain technologies, such as messaging protocols or cross-chain governance.
+
+### EVM Compatibility
+
+The Darwinia network is built to be fully compatible with the Ethereum network, which means it supports the Ethereum Virtual Machine (EVM) and all its associated opcodes. Additionally, the Darwinia network is compatible with the Ethereum JSON-RPC API, which allows developers to interact with the network using the same set of APIs used in the Ethereum network. This compatibility also extends to the gas model, which means the gas costs associated with transactions on the Darwinia network are calculated in the same way as those on the Ethereum network. The result of this compatibility is that applications built on other EVM chains are able to be deployed and used on the Darwinia network without any changes or modifications.
+
+### Security and  Decentralized
 
-Darwinia is currently at the forefront of developing innovative cross-chain service solutions, with a strategic focus on **enhancing the cross-chain capabilities of decentralized applications**. As the industry landscape continues to evolve, Darwinia is committed to staying ahead of the curve by introducing new solutions that align with our core mission. Our approach is not only about meeting current needs but also about anticipating future requirements, ensuring that we remain a leader in the field.
+The Darwinia network is a parachain of the Polkadot, which means it shares the same level of security as Polkadot. This allows us to focus on providing better cross-chain services to our users, while also ensuring the security of user assets stored in our network.

docs/learn/ethereum-compatibility/account-system.md

@@ -1,4 +1,4 @@
-# Account System
+# Substrate Or Ethereum Account
 
 The Darwinia network aspires to be a robust smart contract platform that boasts high compatibility with Ethereum. One of the primary areas of incompatibility lies in the account system. Utilizing the Substrate framework, Darwinia's default account system and signature protocols are significantly different from Ethereum's. This discrepancy means users cannot leverage Ethereum's battle-tested tools directly, necessitating additional learning to navigate our platform effectively. Such a requirement poses a barrier to entry for both casual traders and seasoned application developers.
 

docs/learn/ethereum-compatibility/gas.md

@@ -6,7 +6,7 @@ One concern for smart contract developers is the gas mechanism. If there is a la
 
 As explained above, Darwinia's EVM highly relies on opcode compatibility with the official Ethereum implementation. However, the unique underlying blockchain framework complicates matters. One key concept in the Polkadot relay chain and parachain architecture is "proof size". For parachains, there's a proof size limit of 5M; if exceeded, the relay chain will reject the inclusion of the parachain block, causing the parachain to hang. Considering this limitation, Darwinia's EVM gas calculation incorporates two components: opcode gas, identical to Ethereum's, and proof size cost. The final gas calculation is the greater of these two values. If discrepancies in gas usage are observed during contract interactions compared to Ethereum, this may be the underlying cause. We are actively seeking additional methods to resolve this problem.
 
-## BlockGasLimit Limitation
+## `BlockGasLimit` Limitation
 
 In Ethereum, the number of pending transactions that can be included in the next block depends on the amount of gas each transaction consumes. When miners create new blocks, the total gas limit of all transactions in the block must be less than the block's gas limit. Since the London hard fork, each block has a target size of 15 million gas units, but the actual size of a block can vary depending on network demand. The maximum size of a block, known as the block gas limit, is set to **30 million** gas units.
 

docs/learn/ethereum-compatibility/overview.md

@@ -0,0 +1,5 @@
+# Overview
+
+The Darwinia network inherits its EVM compatibility from the Polkadot EVM layer [Frontier](https://github.com/polkadot-evm/frontier). It keeps up with the latest Ethereum innovations, maintains opcode compatibility, and makes an effort to minimize incompatibility issues for applications developed on the Ethereum chain.
+
+However, there are some key considerations to keep in mind when using the Darwinia network. This chapter serves as an introduction to these important points, and is a valuable resource to refer to when you encounter unexpected issues while developing on Darwinia.

docs/learn/governance.md

@@ -1,10 +1,8 @@
 # Governance
 
-Currently, Darwinia employs OpenGov for governance. For more details on how it functions, please consult the Polkadot official [WIKI](https://wiki.polkadot.network/docs/learn-polkadot-opengov-index).
+Currently, Darwinia employs OpenGov for governance. For more details on how it functions, please consult the Polkadot official [WIKI](https://wiki.polkadot.network/docs/learn-polkadot-opengov-index). We plans to transition from OpenGov to Tally in the future.
 
-Darwinia plans to transition from OpenGov to Tally in the future.
-
-Check out the [tutorial](../community/guide/governance.md).
+Check out the [tutorial](../community/guide/governance.md) for how to use it.
 
 ## Parameters
 

mkdocs.yml

@@ -20,7 +20,6 @@ theme:
     - content.code.copy
     - content.tooltips
     - navigation.footer
-    - navigation.indexes
     - navigation.sections
     - navigation.tabs
     - navigation.top
@@ -311,14 +310,15 @@ plugins:
         "community/ktondao.md": "community/orgs/ktondao.md"
 
 nav:
-  - Home: "index.md"
   - Learn:
+      - What is Darwinia?: "index.md"
+      - Governance: "learn/governance.md"
       - Ethereum Compatibility:
-          - Account System: "learn/ethereum-compatibility/account-system.md"
+          - Overview: "learn/ethereum-compatibility/overview.md"
           - JSON-RPC APIs: "learn/ethereum-compatibility/jsonrpc.md"
+          - Substrate Or Ethereum Account: "learn/ethereum-compatibility/account-system.md"
           - Gas: "learn/ethereum-compatibility/gas.md"
           - EVM Tracing: "learn/ethereum-compatibility/evm-tracing.md"
-      - Governance: "learn/governance.md"
       - Collator Staking: "learn/collator-staking.md"
       - FAQ: "learn/faq.md"
   - Developers: