Mixin and parrent selectors 6/9 The infamous $stripes


Soooo i wrote this code and for some reason i cant make it work.... ive seen other people get stuck the same place, i have been trying new browsers etc. i simply cant figure out if its my code or a bug?? every help would be appreciated.

@mixin transition($time){
transition: $time;
-webkit-transition: $time;
-moz-transition: $time;
-o-transition; $time;

@mixin transform-style($style){
transform-style: $style;
-moz-transform: $style;
-o-transform-style: $style;
-ms-transform-style: $style;
-webkit-transform-style: $style;

@mixin backface-visibility ($visibility:hidden) {

//Add an argument
backface-visibility: $visibility;
-webkit-backface-visibility: $visibility;
-moz-backface-visibility: $visibility;
-ms-backface-visibility: $visibility;
-o-backface-visibility: $visibility;

@mixin stripes($direction, $width-percent, $stripe-color, $stripe-background: #FFF) {
background: repeating-linear-gradient(
$stripe-background ($width-percent - 1),
$stripe-color 1%,
$stripe-background $width-percent

@mixin transform($transformation) {
transform: $transformation;
-webkit-transform: $transformation;
-moz-transform: $transformation;
-ms-transform: $transformation;
-o-transform: $transformation;

@mixin photo-content {
object-fit: cover;

$stripe-properties: to bottom, 15%, blue, white;

//Add your own mixins here

.notecard {

width: 300px;
height: 180px;
border: 1px solid black;
display: inline-block;
margin: 20px;
font-family: Roboto, sans-serif;
box-shadow: 1px 1px 2px 2px rgba(0,0,0,.2);

@include transform-style(preserve-3d);
@include transition(0.4s);

@include transform (rotatey(-180deg));

.front, .back {
width: 100%;
height: 100%;
position: absolute;
@include backface-visibility;

.front {
z-index: 3;
font-size: 20px;

.word {
display: block;
text-align: center;
position: relative;
top: 40%;

.back {
z-index: 1;
word-wrap: break-word;
line-height: 1.6;
@include transform(rotatey(-180deg));
.definition {
width: 100%;
height: 100%;
@include stripes($stripe-properties...);

.photo {
width: 60%;
margin: 0px auto;