Background Colors and Hover Over

• w3-blue-a with w3-blue-b-hover
• w3-yellow-a with w3-yellow-b-hover
• w3-gray-a with w3-gray-b-hover
• w3-blue-b with w3-blue-c-hover
• w3-yellow-b with w3-yellow-c-hover
• w3-gray-b with w3-gray-c-hover
• w3-blue-c with w3-blue-a-hover
• w3-yellow-c with w3-yellow-a-hover
• w3-gray-c with w3-gray-a-hover

Background Colors and Hover Over

• w3-blue-a with w3-blue-b-hover
• w3-yellow-a with w3-yellow-b-hover
• w3-gray-a with w3-gray-b-hover
• w3-blue-b with w3-blue-c-hover
• w3-yellow-b with w3-yellow-c-hover
• w3-gray-b with w3-gray-c-hover
• w3-blue-c with w3-blue-a-hover
• w3-yellow-c with w3-yellow-a-hover
• w3-gray-c with w3-gray-a-hover