.main-header{position:fixed;top:0;left:0;width:100%;z-index:100;transition:background-color .3s ease-in-out;box-sizing:border-box}.main-header.header-scrolled{background-color:#333333a6;box-shadow:0 2px 5px #0000001a;color:#fff}@keyframes borderGradient{0%{background-position:0% 50%}50%{background-position:100% 50%}to{background-position:0% 50%}}.animate-gradient-border{background-size:300% 300%;animation:borderGradient 8s ease infinite}