LESS Parse Error, but I can't find the issue - css

Question

I need a 2nd pair of eyes. LESS keeps giving me a parse error, but I can't find it. I've broken the code down in sections and have removed/added things line-by-line with no luck. I've inherited this code from another teamj.
I suspect that they were using an older version of LESS, but they gave me no docs.
Any and all help is appreciated!
.panel-cards {
overflow-y: visible;
overflow-x: hidden;
.deck {
display: flex;
overflow: visible;
overflow-x: scroll;
//-webkit-overflow-scrolling: touch; //conflict with modal popups (and unnecessary?)
&:after {
content: '';
width: 1px;
height: 100px;
display: block;
flex-shrink: 0;
}
}
article {
flex-shrink: 0;
display: flex;
flex-direction: column;
width: unit(294/4.14,vw);
margin: 0 unit(15/4.14,vw) unit(30/4.14,vw) unit(15/4.14,vw);
.image {
background-position: center center;
background-size: cover;
background-repeat: no-repeat;
.box-sizing(border-box);
padding-top: 71%;
overflow: hidden;
max-width: 100%;
&.contain {
background-size: contain;
}
}
.copy {
.box-sizing(border-box);
.copy {
span {
width: 100%;
float: left;
p{
margin: 0px 0px 8px 0px;
line-height: 120%;
font-family: 'Roboto', Helvetica, Arial, sans-serif;
font-weight: 600;
text-align: left;
vertical-align: baseline;
}
}
h3 + p {
margin-top: 0;
}
p {
margin: unit(18/4.14,vw) 0;
font-weight: #medium;
line-height: 117%;
}
a:not(.btn) {
color: #green;
font-weight: #bold;
&:hover {
color: #green;
}
}
}
}
} //end panel-cards

Answer 1

Correct these: font-weight: #medium;
color: #green;
font-weight: #bold;
color: #green; and also, "}" has a mismatch between open and closes.

Answer 2

Is this what you're looking for?
.panel-cards {
overflow-y: visible;
overflow-x: hidden;
}
.panel-cards .deck {
display: flex;
overflow: visible;
overflow-x: scroll;
}
.panel-cards .deck:after {
content: '';
width: 1px;
height: 100px;
display: block;
flex-shrink: 0;
}
.panel-cards article {
flex-shrink: 0;
display: flex;
flex-direction: column;
width: 71.01449275vw;
margin: 0 3.62318841vw 7.24637681vw 3.62318841vw;
}
.panel-cards article .image {
background-position: center center;
background-size: cover;
background-repeat: no-repeat;
box-sizing: border-box;
padding-top: 71%;
overflow: hidden;
max-width: 100%;
}
.panel-cards article .image.contain {
background-size: contain;
}
.panel-cards article .copy {
box-sizing: border-box;
}
.panel-cards article .copy .copy span {
width: 100%;
float: left;
}
.panel-cards article .copy .copy span p {
margin: 0px 0px 8px 0px;
line-height: 120%;
font-family: 'Roboto', Helvetica, Arial, sans-serif;
font-weight: 600;
text-align: left;
vertical-align: baseline;
}
.panel-cards article .copy .copy h3 + p {
margin-top: 0;
}
.panel-cards article .copy .copy p {
margin: 4.34782609vw 0;
font-weight: medium;
line-height: 117%;
}
.panel-cards article .copy .copy a:not(.btn) {
color: green;
font-weight: bold;
}
.panel-cards article .copy .copy a:not(.btn):hover {
color: green;
}