CSS does not work. how can this problem be solved?

CSS does not work. some css does not work. is it related to php? Php part: PHPcodeif ($ auth = true) {echo & quot; & lt; tr & gt; & quot; echo & quot; & lt; tdclass = 'block _ link' id = 'block _ link' & gt; & l CSS does not work
Some css does not work. is it related to php?
Php section:

PHP code

  if($auth==true){    echo "";    echo "You have\$$credit";    echo "Start Order";    echo "View Order";    echo "Edit Profile";    echo "Change Password";    echo "Recharge My Account";    echo "Logout";    echo "";}

CSS section

CSS code

  . Block_link a {width: 120px; height: 50px; display: block; background-color: # f1f1f1; text-align: center; font-size: 10.5pt; text_decoration: none; // removing the link underline does not work. padding-top: 30px ;}. block_link a: link, block_link a: visited // here a: visited does not work either. {background-color: # f1f1f1; text_decoration: none; // removing the link underline does not work color: # 009EDD ;}. block_link a: hover {background-color: # 009EDD; text_decoration: none; // The color: # ffffff;} # block_link {background-color: # d34836; color: # ffffff; width: 120px ;}

What the hell is going on?

------ Solution --------------------
Text-decoration
Not _
------ Solution --------------------
Text-decoration: none;
What about you?
Text_decoration: none;

Do not commit all sins to php
To be honest, php is already under too much pressure.