Ubuntu Tech & Life

Achieving Alignment and Indentation Effects in Q&A Scenarios Using CSS In technical documentation or blogs, Q&A formatting is very common. To make the content clearer and more readable, we usually want questions and answers to be aligned, and answers to be automatically indented when they wrap to a new line. Today, I will share a practical CSS technique to achieve this effect using the padding-left and text-indent properties. Problem Scenario Assume we have the following Q&A content: Q: What is CSS? A: CSS (Cascading Style Sheets) is a style sheet language used to describe the appearance of HTML documents. Q: How to achieve left alignment using CSS? A: You can achieve this by setting the `padding-left` and `text-indent` properties. The desired effects are: Questions and answers are left-aligned. Answers are automatically indented when they wrap to a new line, aligning with the first line. Implementation Method Using the padding-left and text-indent propertie...

Understanding BEM Naming: A Powerful Tool for Enhancing CSS Code Maintainability In modern web development, as the scale of front-end projects continues to grow, writing clear, maintainable, and highly reusable CSS code has become a critical challenge. The BEM (Block Element Modifier) naming convention serves as an effective solution and is widely applied in building modular and scalable user interfaces. This article delves into the concepts, advantages, and practical application cases of BEM. What is BEM? BEM is a methodological approach to CSS class naming aimed at enhancing team collaboration efficiency and reducing complexity in large-scale projects through structured naming rules. It consists of three main components: Block : Represents an independent functional unit or component, such as buttons, menus, etc. Element : Part of a specific Block that cannot exist independently outside its parent Block. Modifier : Defines different states or variants of a Block or Element. B...

Optimizing Class Name Management with CSS Attribute Selectors In modern web development, managing class names in HTML and CSS is a common challenge. As projects grow in size, the stacking and repeated use of class names often lead to bloated and hard-to-maintain CSS code. This article introduces how to leverage CSS’s special attribute selectors to manage class names in a more elegant and efficient way. The Problem In HTML, we frequently use class names to define element styles. For example: < div class = "bestseller out-of-stock" > ... </ div > As the project evolves, the number of class names can grow significantly, making the CSS code difficult to maintain. For example: .bestseller { ... } .out-of-stock { ... } In such cases, the CSS file becomes lengthy and hard to manage. The Power of CSS Attribute Selectors CSS provides three special attribute selectors that are similar in concept to regular expressions, helping us filter class names more flexibly ...

Font Management in International Project Development: Avoiding Design and Preview Inconsistencies Due to Missing Local Fonts When developing international software, especially products targeting the European and American markets, developers and designers often encounter complex environments involving multiple languages and fonts. Compared to domestic projects, foreign projects tend to use a wider variety of fonts, with a single page potentially containing several different fonts, and the entire project using a significantly larger number of fonts. This is mainly because font files for English and other Latin-based scripts are relatively small, making it easier to introduce diverse fonts to achieve rich visual effects. However, in regions like China that use non-Latin character sets, the situation is different. Chinese font packages typically contain a large number of characters (such as Chinese characters), which makes individual font files much larger than those for English fonts. T...

Quickly Set Up a Cloud Database Using MongoDB Atlas MongoDB Atlas is the official fully managed cloud database service from MongoDB, simplifying the deployment, management, and scaling of MongoDB in the cloud. This article will guide you on how to quickly create a MongoDB Atlas cluster and set up basic connection configurations. Creating a MongoDB Atlas Cluster Sign Up & Log In If you do not have a MongoDB Atlas account yet, head over to MongoDB Atlas to sign up. After logging in, click on “Build a Cluster” to start creating a new cluster. Select Cluster Configuration To meet the needs of most development and testing scenarios, you can choose the free tier (M0) shared cluster, which is usually sufficient for small applications or personal projects. When choosing a cloud provider, select based on your preference. Here we chose Azure, but AWS and GCP are also great choices. Specify Geographic Location For geographic location selection, choose according to your u...

Configuring SSH Access to a Docker Container via an Alternative Port If you want to configure SSH access to a Docker container using an alternative port, such as port 6666 , follow the steps below carefully. This guide assumes that you have administrative access to your Docker host and are familiar with basic Linux commands. Step 1: Run the Container with SSH Service Start by running a new container from your image with port 6666 on the host mapped to port 22 inside the container: sudo docker run -it -p 6666 : 22 --name ssh-container testimage Make sure to replace testimage with the actual name of your Docker image. The --name option gives the container a specific name for easier management. Step 2: Install OpenSSH Server in the Container Once inside the container, update the package list and install the OpenSSH server: apt-get update && apt-get install -y openssh-server Step 3: Set the Root Password Set a password for the root user, which will be required when l...

Guide to Modifying Docker Container Port Mappings If you need to modify the port mappings for an existing Docker container, such as one with the ID 123456 , follow these steps carefully. This guide assumes that you have administrative access to the Docker host and are familiar with using a text editor like vim on Linux systems. service docker stop Step 1: Modify hostconfig.json First, edit the hostconfig.json file located in the container’s directory: sudo vim /var/lib/docker/containers/ 123456 /hostconfig.json Look for the "PortBindings" configuration. If your container was started with port mappings, this object will not be empty. Add or update the port bindings as follows: { " PortBindings ": { " 5700/tcp ": [{ " HostIp ": "" , " HostPort ": "10086" }] , " 6700/tcp ": [{ " HostIp ": "" , " HostP...

Background of the Issue When developing projects with Nuxt.js, it’s common to encounter a large number of Sass-related warning messages in the console. These warnings mainly include: Warnings about the order of mixin declarations. Warnings about the use of Legacy JS API. Although these warnings do not affect the operation of the program, they can degrade the development experience by cluttering the console. Today, we will explore how to elegantly address this issue. Solutions 1. Disable Warnings via Configuration In the nuxt.config.js file, we can modify the Sass configuration to suppress these warning messages: export default { build: { loaders: { scss: { sassOptions: { quietDeps: true , // Suppress warnings from dependencies logger: { warn: function ( message ) { return null ; // Silence warning messages }, debug: function ( message ) { return null ; // Silence ...

Guide to Troubleshooting MySQL Remote Connection Issues in a Docker Environment Problem Description A MySQL database running within a Docker container appears to be functioning correctly, with port 3306 mapped to the host machine. However, it is not possible to connect to the MySQL service from either the local machine or external networks. Problem Analysis This is typically a Docker network access permission issue. The error logs indicate that access attempts from the Docker default bridge IP (172.17.0.1) are being denied, suggesting that there might be a problem with the MySQL user permissions configuration. Resolution Steps 1. Reset MySQL User Permissions First, enter the MySQL container and reset the user permissions: # Enter the MySQL container docker exec -it your_mysql_container bash # Connect to MySQL mysql -u root -p # Check current user permissions SELECT user, host FROM mysql.user; # Remove existing root user settings DROP USER 'root' @ '%' ; ...

Learning the LED Blink with Arduino Uno My first step in learning about Arduino Uno was experimenting with making an LED blink. There’s a technical detail worth noting here: the L LED soldered onto the board is connected to digital pin 13, which means in the code LED_BUILTIN is equivalent to pin 13. What is the Purpose of the L Soldered LED? The L LED serves multiple purposes: Factory Testing: It allows manufacturers to quickly verify that the board is functioning correctly by checking if the LED blinks after uploading a simple blink sketch. Convenience for Users: This LED also provides convenience for users as it can be used for basic tests or debugging without needing to connect any external LEDs. For instance, you can upload a blinking sketch and see if the LED blinks as expected, ensuring that your code and board are working properly. This built-in feature simplifies initial testing and development, especially for beginners who might not have additional components at h...

My Arduino Journey 01 Today, I got my hands on an Arduino Uno, marking the beginning of what I hope will be a rewarding journey into hardware projects. I encountered some minor issues during my first setup, and I’m documenting them here so that others can avoid making the same simple mistakes. I’m using Windows 11. After plugging in the Uno to my computer, it should have appeared as a device with a question mark in the Device Manager. However, there was no response for quite some time. It wasn’t until I gave it a firm push that I realized the issue: the port on the Uno side is somewhat tight, requiring a bit more force than expected; otherwise, it only powers up without transferring data… Apart from this, everything else follows the standard tutorial procedures. By the way, if the latest IDE doesn’t install the drivers properly, you can download version 1.0.x of the IDE and manually install the drivers from the drivers folder. This mistake was so trivial that I sincerely hope n...

How to Write Alpine.js Components When using Alpine.js, you may have encountered the challenge of how to structure components. Unlike Vue or React which are component-first, Alpine’s documentation keeps componentization relatively subtle. Here, we provide two approaches for writing components in Alpine.js. You can consider both methods and choose according to your preference. Morph The official Alpine.js site offers a tool called Morph that can be used to achieve component functionality. Firstly, add this plugin above where you normally include Alpine, as follows: < script src = "libs/alpine.morph.min.js" defer > </ script > < script src = "libs/alpine.min.js" defer > </ script > < script defer src = "components/sc-loading.js" > </ script > The CDN link is CDN . Download it to your server to ensure proper use by domestic users. The sc-loading.js file contains the component code. Write it like this: ...

# Handling Scoped Styles for External Elements in Vue When developing with Vue.js, you may encounter the need to style externally imported components (such as Element UI). Since these components are dynamically generated at runtime and do not carry a `data-v` attribute, styles defined within `<style scoped>` do not apply to them. This article will introduce three methods to solve this issue. ## Method 1: Using `/deep/` or `>>>` Operator This is the most common solution, which involves using deep selectors (like `/deep/` or `>>>` ) to let scoped styles affect child components. However, it's worth noting that `/deep/` has been deprecated; it's recommended to use `::v-deep` as an alternative. ``` vue < template > < el-button class = "custom-button" > Button </ el-button > </ template > < style scoped > .custom-button { / * Regular styles * / } / * Affecting child components using ::v-deep * / ::...