HTML Guide for letter-spacing

CSS: “letter-spacing”: “NaNrem” is not a “letter-spacing” value.

The CSS letter-spacing property controls the space between characters in text. The error you’re encountering indicates that an invalid value is being specified for this property. Specifically, NaNrem (where NaN stands for “Not-a-Number”) is not a valid numeric value.

Explanation

In CSS, letter-spacing can be defined using various units, such as:

Length units like px, em, rem, etc.
Keywords like normal.

However, these values need to be real numbers, not NaN, which indicates a computational error likely from JavaScript or during dynamic style generation.

Example of Correct Usage

If you want to set the letter spacing to a specific value, ensure it’s a valid number. For instance, to set a 0.1 rem spacing:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Correct Letter Spacing</title>
  <style>
    .text {
      letter-spacing: 0.1rem;
    }
  </style>
</head>
<body>
  <p class="text">This is a sample text with correct letter spacing.</p>
</body>
</html>

Troubleshooting Steps

Check the CSS Source: Look at where letter-spacing is being set in your CSS and ensure you are using a valid number.
Review JavaScript Calculations: If the value is coming from JavaScript, ensure that calculations do not result in NaN. This could happen if you divide by zero or use undefined variables.

// Example of avoiding NaN
let spacing = 2; // Ensure this is a valid number
document.querySelector('.text').style.letterSpacing = `${spacing}rem`;

Default Fallback: Use a conditional check or default fallback in JavaScript to prevent NaN.

let spacingValue = calculateSpacing() || 0.1; // Use 0.1 rem as fallback
document.querySelector('.text').style.letterSpacing = `${spacingValue}rem`;

By resolving these issues, the error should be corrected and the text will render with proper letter-spacing settings.