This is just a basic but very common CSS mistake, you see you cannot have IDs or classes that begin with a number, just update those and it's that simple.
I also recommend you to use SASS as with a loop you'll be able to generate that kind of sequential CSS quite easy: https://stackoverflow.com/a/19088399/3362991
Please take your time to read through the CSS W3C Spec:
w3.org/TR/CSS21/syndata.html#characters
In CSS, identifiers (including element names, classes, and IDs in
selectors) can contain only the characters [a-zA-Z0-9] and ISO 10646
characters U+00A0 and higher, plus the hyphen (-) and the underscore
(_); they cannot start with a digit, two hyphens, or a hyphen followed
by a digit. Identifiers can also contain escaped characters and any
ISO 10646 character as a numeric code (see next item). For instance,
the identifier "B&W?" may be written as "B&W?" or "B\26 W\3F".