/* Top 버튼 스타일 */
#top-btn {
    position: fixed;
    right: 32px;
    bottom: 40px;
    z-index: 100;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, #4fd1c5 60%, #7f5af0 100%);
    color: #fff;
    border: none;
    box-shadow: 0 4px 16px rgba(79,209,197,0.18);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    cursor: pointer;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s, background 0.2s;
}
#top-btn.show {
    opacity: 1;
    pointer-events: auto;
}
#top-btn:hover {
    background: linear-gradient(135deg, #7f5af0 60%, #4fd1c5 100%);
}
@media (max-width: 700px) {
    #top-btn { right: 12px; bottom: 16px; width: 40px; height: 40px; font-size: 1.5rem; }
}
/* Aurora 배경 효과 */
.aurora-bg {
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    z-index: 0;
    pointer-events: none;
    overflow: hidden;
}
.aurora {
    position: absolute;
    width: 60vw;
    height: 60vw;
    min-width: 400px;
    min-height: 400px;
    background: radial-gradient(circle at 30% 30%, #4fd1c5cc 0%, #23272f00 80%),
                radial-gradient(circle at 70% 70%, #7f5af0bb 0%, #23272f00 80%),
                radial-gradient(circle at 80% 20%, #ffb86b99 0%, #23272f00 80%);
    filter: blur(80px);
    opacity: 0.7;
    animation: auroraMove 16s linear infinite alternate;
}
@keyframes auroraMove {
    0% { transform: translate(-10vw, -10vh) scale(1.1); }
    100% { transform: translate(10vw, 10vh) scale(1.2); }
}
/* 좌우 네온 라인 애니메이션 */
.neon-bar {
    position: fixed;
    top: 0;
    width: 18px;
    height: 100vh;
    z-index: 2;
    pointer-events: none;
    opacity: 0.7;
}
.neon-bar.left {
    left: 0;
    background: linear-gradient(180deg, #4fd1c5 0%, #7f5af0 50%, #ffb86b 100%);
    box-shadow: 0 0 32px 8px #4fd1c5cc;
    animation: neonMoveLeft 7s ease-in-out infinite alternate;
}
.neon-bar.right {
    right: 0;
    background: linear-gradient(0deg, #ffb86b 0%, #7f5af0 50%, #4fd1c5 100%);
    box-shadow: 0 0 32px 8px #7f5af0cc;
    animation: neonMoveRight 8s ease-in-out infinite alternate;
}
@keyframes neonMoveLeft {
    0% { filter: blur(2px) brightness(1.1) drop-shadow(0 0 12px #4fd1c5); transform: scaleY(1) translateY(0); }
    50% { filter: blur(8px) brightness(1.3) drop-shadow(0 0 32px #4fd1c5); transform: scaleY(1.08) translateY(-2vh); }
    100% { filter: blur(2px) brightness(1.1) drop-shadow(0 0 12px #4fd1c5); transform: scaleY(1) translateY(0); }
}
@keyframes neonMoveRight {
    0% { filter: blur(2px) brightness(1.1) drop-shadow(0 0 12px #7f5af0); transform: scaleY(1) translateY(0); }
    50% { filter: blur(8px) brightness(1.3) drop-shadow(0 0 32px #7f5af0); transform: scaleY(1.08) translateY(2vh); }
    100% { filter: blur(2px) brightness(1.1) drop-shadow(0 0 12px #7f5af0); transform: scaleY(1) translateY(0); }
}
@media (max-width: 700px) {
    .neon-bar { display: none; }
}
body {
    font-family: 'Segoe UI', Arial, sans-serif;
    background: linear-gradient(135deg, #181c24 0%, #23272f 100%);
    background-attachment: fixed;
    margin: 0;
    padding: 0;
    color: #e3e6ed;
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
    /* subtle pattern overlay */
    /* Optional: add a SVG pattern or noise texture for more visual interest */
}

/* 네비게이션 */
.navbar {
    background: #222e3a;
    color: #fff;
    padding: 0 0;
    box-shadow: 0 2px 8px rgba(0,0,0,0.04);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: box-shadow 0.3s;
}
.glow-nav {
    box-shadow: 0 0 16px 0 #4fd1c5cc, 0 2px 8px rgba(0,0,0,0.08);
}
.nav-container {
    max-width: 900px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    height: 60px;
}
.nav-logo {
    font-size: 1.5rem;
    font-weight: bold;
    letter-spacing: 1px;
}
.nav-links {
    list-style: none;
    display: flex;
    gap: 24px;
    margin: 0;
    padding: 0;
}
.nav-links li a {
    color: #fff;
    text-decoration: none;
    font-size: 1.05rem;
    transition: color 0.2s;
}
.nav-links li a:hover {
    color: #4fd1c5;
}

main {
    max-width: 900px;
    margin: 0 auto;
    padding: 32px 16px 0 16px;
}

.section {
    margin-bottom: 48px;
    background: rgba(30, 34, 44, 0.92);
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.18);
    padding: 32px 24px;
    backdrop-filter: blur(1.5px);
    border: 1.5px solid rgba(80,90,110,0.18);
}
.about {
    display: flex;
    align-items: center;
    gap: 32px;
}
.profile-img img {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid #4fd1c5;
    background: #eee;
}
.about-content h2 {
    margin-top: 0;
    color: #4fd1c5;
    font-size: 1.6rem;
    text-shadow: 0 2px 8px rgba(0,0,0,0.18);
}
.about-content p {
    color: #bfc6d1;
    font-size: 1.1rem;
    margin-bottom: 0;
}

.skills h2, .portfolio h2, .contact h2 {
    color: #4fd1c5;
    font-size: 1.4rem;
    margin-top: 0;
    border-bottom: 2px solid #4fd1c5;
    padding-bottom: 6px;
    margin-bottom: 24px;
    text-shadow: 0 2px 8px rgba(0,0,0,0.18);
}
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 20px;
}
.skill-card {
    background: rgba(36, 40, 52, 0.98);
    border-radius: 10px;
    padding: 18px 14px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.10);
    border: 1px solid rgba(80,90,110,0.18);
    transition: box-shadow 0.3s, filter 0.3s;
}
.skill-card:hover {
    box-shadow: 0 0 24px 0 #4fd1c5cc, 0 2px 8px rgba(0,0,0,0.10);
    filter: brightness(1.08) saturate(1.2);
}
.skill-card h3 {
    margin-top: 0;
    color: #4fd1c5;
    font-size: 1.1rem;
}
.skill-card ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.skill-card li {
    color: #bfc6d1;
    padding: 4px 0;
    font-size: 1rem;
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}
.portfolio-card {
    background: rgba(36, 40, 52, 0.98);
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.10);
    padding: 16px 12px 20px 12px;
    text-align: center;
    transition: transform 0.15s, box-shadow 0.3s, filter 0.3s;
    border: 1px solid rgba(80,90,110,0.18);
}
.portfolio-card:hover {
    transform: translateY(-6px) scale(1.03);
    box-shadow: 0 0 32px 0 #7f5af0cc, 0 4px 24px rgba(79,209,197,0.18);
    filter: brightness(1.08) saturate(1.2);
}
.portfolio-card:hover {
    transform: translateY(-6px) scale(1.03);
    box-shadow: 0 4px 24px rgba(79,209,197,0.18);
}
.portfolio-card img {
    width: 100%;
    max-width: 260px;
    border-radius: 8px;
    margin-bottom: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.10);
}
.portfolio-card h3 {
    margin: 8px 0 6px 0;
    color: #4fd1c5;
    font-size: 1.1rem;
}
.portfolio-card p {
    color: #bfc6d1;
    font-size: 0.98rem;
}

.contact-list {
    list-style: none;
    padding: 0;
    margin: 0;
    font-size: 1.08rem;
}
.contact-list li {
    margin-bottom: 10px;
}
.contact-list a {
    color: #4fd1c5;
    text-decoration: none;
    word-break: break-all;
    font-weight: 500;
}
.contact-list a:hover {
    text-decoration: underline;
    color: #fff;
}

.footer {
    text-align: center;
    color: #bfc6d1;
    font-size: 0.98rem;
    padding: 24px 0 18px 0;
    background: none;
}

@media (max-width: 700px) {
    .about {
        flex-direction: column;
        gap: 18px;
        text-align: center;
    }
    .nav-container {
        flex-direction: column;
        height: auto;
        gap: 8px;
        padding: 8px 8px;
    }
    main {
        padding: 16px 2vw 0 2vw;
    }
    .section {
        padding: 18px 8px;
    }
}