.course-info {
    .container {
        header.course-profile {
            .intro-inner-wrapper {
                .intro {
                    .main-cta {
                        span.sneakpeek {
                            width: 49%;
                            box-sizing: border-box;
                            margin: 0 0 0 2%;
                            padding: 15px 0 14px 0;
                            float: left;
                            background: $button-archive-color;
                            border: 1px solid darken($button-archive-color, 50%);
                            border-radius: 5px;
                            text-align: center;
                            letter-spacing: 1px;
                            color: darken($button-archive-color, 50%);
                        }
                    }
                }
            }
        }
    }
    .sneakpeek-warning {
        clear: both;
        padding-top: 10px;
    }
    .sneakpeek-warning:before {
        content: '* ';
    }
}

.course-info {
    header.course-profile {
        .intro-inner-wrapper {
            .intro {
                .main-cta {
                    span.sneakpeek {
                        background: $button-archive-color;
                        border: 1px solid darken($button-archive-color, 50%);
                        border-radius: 5px;

                        @include box-sizing(border-box);

                        color: darken($button-archive-color, 50%);
                        display: block;
                        letter-spacing: 1px;
                        padding: 15px 20px;
                        text-align: center;

                        @include float(left);
                        @include margin(0, 0, 0, 2%);
                        @include transition(none);

                        width: flex-grid(4, 8);
                    }
                }
            }
        }
    }
    .sneakpeek-warning {
        clear: both;
        padding-top: 10px;
    }
    .sneakpeek-warning:before {
        content: '* ';
    }
}

Remove one css selection level to make it work
Remove one css selection level to make it work
