Accessibility fix guides

Short, practical fixes for the most common automatically detectable WCAG failures.

• Declare the page language (WCAG 3.1.1)
• Give every page a descriptive title (WCAG 2.4.2)
• Add alt text to images (WCAG 1.1.1)
• Label every form field (WCAG 1.3.1 / 4.1.2)
• Give links accessible text (WCAG 2.4.4)
• Give buttons accessible text (WCAG 4.1.2)
• Title your iframes (WCAG 4.1.2)
• Never disable zoom (WCAG 1.4.4)
• Do not skip heading levels (WCAG 1.3.1)
• Give each page one h1 (WCAG 1.3.1)
• Keep ids unique (WCAG 4.1.2)