import re


def parse_config(content):
    """Parse configuration options into a dict.

    Blank lines are ignored. Lines beginning with a hash mark (`#`) are comments, and ignored.
    Valid lines are made of an option's name (a sequence of non-blanks), followed by a value.
    The value starts with the first non-blank character after the option's name, and terminates at
    the end of the line, or at the last sequence of blanks before the end of the line.
    Option names are case-insensitive, and converted to lower-case.

    Arguments:
        content (str): The content of a configuration file to parse.
    Returns:
        dict: Parsed options.
    """
    return {
        match.group(1).lower(): match.group(2)
        for match in (
            re.match(r'^(\w+)\s+([^#]+\b)', line)
            for line in content.splitlines()
        ) if match
    }