How can i change the text style and color of this text?

Hi Alex

Thanks for reaching out.

For the button, try:

/* WooCommerce */

.woocommerce ul.products li.product a.button:hover {
    border-bottom: 1px solid;
    border-color: #2d608d #2a5b85 #275379;
}

#sml_subscribe_widget .btn {
	font-size: 1em;
    background: #3d82bf;
    background: -webkit-gradient(linear,left bottom,left top,color-stop(0,#316898),color-stop(1,#3d82bf));
    background: -ms-linear-gradient(bottom,#316898,#3d82bf);
    background: -moz-linear-gradient(center bottom,#316898 0%,#3d82bf 100%);
    background: -o-linear-gradient(#3d82bf,#316898);
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#3d82bf',endColorstr='#316898',GradientType=0);
    border: 1px solid;
    border-color: #2d608d #2a5b85 #275379;
    color: #fff !important;
    -webkit-border-radius: 0;
    -moz-border-radius: 0;
    border-radius: 0;
    -webkit-box-shadow: inset 0 1px 0 rgba(255,255,255,0.2), 0 1px 2px rgba(0,0,0,0.065);
    -moz-box-shadow: inset 0 1px 0 rgba(255,255,255,0.2), 0 1px 2px rgba(0,0,0,0.065);
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.2), 0 1px 2px rgba(0,0,0,0.065);
    text-shadow: 0 1px 0 rgba(0,0,0,0.05);
    text-transform: uppercase;	
}

#sml_subscribe_widget .btn:hover {
    background: #2c71ae;
    background: -webkit-gradient(linear,left bottom,left top,color-stop(0,#2c71ae),color-stop(1,#2c71ae));
    background: -ms-linear-gradient(bottom,#2c71ae,#2c71ae);
    background: -moz-linear-gradient(center bottom,#2c71ae 0%,#2c71ae 100%);
    background: -o-linear-gradient(#2c71ae,#2c71ae);
	border-bottom: 1px solid;
    border-color: #2d608d #2a5b85 #275379;
    -webkit-backface-visibility: hidden;
}

I’d need further details to change the text, what are you looking to achieve?

On a side note, try the following in your Custom CSS plugin to help the spacing at the top of this page:

/* Archives */

.archive .site-content {
	padding-top: 2.67857em;;
}

Also, add the following to your Custom CSS to fix a small issue with WooCommerce button hover borders:

/* WooCommerce */

.woocommerce ul.products li.product a.button:hover {
    border-bottom: 1px solid;
    border-color: #2d608d #2a5b85 #275379;
}

Sure. The only difference is font size. You can add:

#sml_subscribe_widget .prepend {
	font-size: 14px;
}