[BUG] Text should be centre aligned in start/reset button.

## Description

**Describe the bug:**
For good UI reasons the text of start/reset button should be centre aligned in pomodoro page

**Expected behavior:**
Text of start/reset button should be in center in pomodoro spiritual break page

**Actual behavior:**
Text is aligned right in start/reset button.

## Reproduction Steps

**Steps to reproduce the behavior:**

1. Go to 'index.html'
2. Click on 'pomodoro spiritual break' from navbar
3. Scroll down to 'start/reset section'
4. See error

## Screenshots

## Additional Information

**Device (please complete the following information):**
- OS: [e.g., Windows, macOS, Linux]
- Browser [e.g., Chrome, Safari, Firefox]
- Version [e.g., 22]

**Additional context:**

Add any other context about the problem here.