.neon {
    position: relative;
    display: flex;
    padding: 10px 10px;
    color: #03e9f4;
    text-decoration: none;
    text-transform: uppercase;
    transition: 0.5s;
    overflow: hidden;
    justify-content: center; /* 가로 중앙 정렬 */
    align-items: center;    /* 세로 중앙 정렬 */    
}
.neon:hover{
    background: #03e9f4;
    color: #050801;
    box-shadow: 0 0 5px #03e9f4,
                0 0 25px #03e9f4,
                0 0 50px #03e9f4,
                0 0 200px #03e9f4;
     -webkit-box-reflect:below 1px linear-gradient(transparent, #0005);
}
.neon:nth-child(1){
    filter: hue-rotate(270deg);
}
.neon:nth-child(2){
    filter: hue-rotate(110deg);
}
.neon span{
    position: absolute;
    display: block;
}
.neon span:nth-child(1){
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg,transparent,#03e9f4);
    animation: animate1 2s linear infinite;
}
@keyframes animate1{
    0%{
        left: -100%;
    }
    50%,100%{
        left: 100%;
    }
}
.neon span:nth-child(2){
    top: -100%;
    right: 0;
    width: 2px;
    height: 100%;
    background: linear-gradient(180deg,transparent,#03e9f4);
    animation: animate2 2s linear infinite;
    animation-delay: 0.50s;
}
@keyframes animate2{
    0%{
        top: -100%;
    }
    50%,100%{
        top: 100%;
    }
}
.neon span:nth-child(3){
    bottom: 0;
    right: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(270deg,transparent,#03e9f4);
    animation: animate3 2s linear infinite;
    animation-delay: 1.00s;
}
@keyframes animate3{
    0%{
        right: -100%;
    }
    50%,100%{
        right: 100%;
    }
}


.neon span:nth-child(4){
    bottom: -100%;
    left: 0;
    width: 2px;
    height: 100%;
    background: linear-gradient(360deg,transparent,#03e9f4);
    animation: animate4 2s linear infinite;
    animation-delay: 1.5s;
}
@keyframes animate4{
    0%{
        bottom: -100%;
    }
    50%,100%{
        bottom: 100%;
    }
}