Hi,
Below are some fixes for the Dark Template for jLex Comment 3.0.1.
I think for the futuer it would be better to rewrite the template so that it adopts to the Joomla template colors.


#jlexcomment .jcm-form {
    border: 2px solid #707070;
}

.jcm-dg-thumb a.upload-thumb,
.jcm-dg-comments .load_more_cm {
    background: #4d4d4d;
}
#jlexcomment button,#jlexcomment button.jcm-btn-post.forMember{background:#5c5c5c}
#jlexcomment button,#jlexcomment button.jcm-btn-post.forMember:hover{background:#4d4d4d}

.jcm-sticker ul.jcm-sticker-gp-hl a {
    background: #666666;
    color: #fff;
}
.jcm-sticker ul.jcm-sticker-gp-hl a.jcm-sticker-active {
    background: #505050;
    border-left: 1px solid #8a8a8a;
    border-right: 1px solid #8a8a8a;

}
.jcm-sticker ._header {
    border-bottom: 1px solid #8f8f8f;
}
.jcm-sticker .jcm-sticker-group a {
    color: #ffffff;
    background: #5a7826;
}
.jcm-sticker .jcm-sticker-group a:hover {
    color: #f5f5f5;
    background: #475e1e;
}

.jcm-sticker ul._list-stickers a:hover {
    background: #444444;
}

.jcm-dialog button,
#jlexcomment .jcm-button {
    background-color: #616161;
    color: #ffffff;
    border: 1px solid #5c5c5c;
}
.jcm-dialog button:hover,
.jcm-dialog button:focus,
#jlexcomment .jcm-button:hover,
#jlexcomment .jcm-button:focus {
    font-size: 12px;
    -webkit-font-smoothing: antialiased;
    cursor: pointer;
    display: inline-block;
    text-decoration: none;
    white-space: nowrap;
    line-height: 22px;
    background-color: #575757;
    color: #f5f5f5;
    border: 1px solid #525252;
    border-radius: 2px;
    font-weight: bold;
    padding: 0 8px;
    position: relative;
    text-align: center;
    text-shadow: none;
    vertical-align: middle;
}
.jcm-dialog button.jup {
    background: #616161;
    border-color: #5c5c5c;
}
.jcm-dialog button.jup:hover,
.jcm-dialog button.jup:focus {
    background: #575757;
    color: #fff;
    border-color: #525252;
    margin: 0 auto;
    display: block;
    padding: 10px 30px;
    font-size: 1.1em;
}
.jcm-dialog .jcm-dg-submit,
#jlexcomment .jcm-button-hl {
    font-size: 12px;
    -webkit-font-smoothing: antialiased;
    cursor: pointer;
    display: inline-block;
    text-decoration: none;
    white-space: nowrap;
    line-height: 22px;
    background-color: #616161;
    color: #ffffff;
    border: 1px solid #5c5c5c;
    border-radius: 2px;
    font-weight: bold;
    padding: 0 8px;
    position: relative;
    text-align: center;
    text-shadow: none;
    vertical-align: middle;
}
.jcm-dialog .jcm-dg-submit:hover,
.jcm-dialog .jcm-dg-submit:focus,
#jlexcomment .jcm-button-hl:hover,
#jlexcomment .jcm-button-hl:focus {
    font-size: 12px;
    -webkit-font-smoothing: antialiased;
    cursor: pointer;
    display: inline-block;
    text-decoration: none;
    white-space: nowrap;
    line-height: 22px;
    background-color: #575757
    color: #f5f5f5;
    border: 1px solid #525252;
    border-radius: 2px;
    font-weight: bold;
    padding: 0 8px;
    position: relative;
    text-align: center;
    text-shadow: none;
    vertical-align: middle;
}

#jlexcomment .jcm-featured > .jcm-post-content > .jcm-flex-content {
    background: rgb(25 46 77 / 30%);
}

#jlexcomment .jcm-extra-admin {
background: rgb(232 231 227 / 5%);
    border: 1px solid #594c40;
    color: #c7c2bd;
}

@-webkit-keyframes yellow-fade {
  0% {background: rgb(204 170 0 / 50%);}
/*  100% {background: #665500;} */
}
@keyframes yellow-fade {
  0% {background: rgb(204 170 0 / 50%);}
/*    100% {background: #665500;} */
}
@-webkit-keyframes yellow-fade-none {
  0% {background: rgba(204 170 0, 0.5);}
  100% {background: none;}
}
@keyframes yellow-fade-none {
  0% {background: rgba(204 170 0, 0.5);}
  100% {background: none;}
}