:root {
  --bg: #0d1117;
  --bg-alt: #161b22;
  --card-bg: #1c2230;
  --border: #2d333b;
  --text: #e6edf3;
  --text-muted: #9198a1;
  --accent: #4ade80;
}

body {
  background-color: var(--bg);
  color: var(--text);

  font-family: "Pretendard", -apple-system, "Segoe UI", "Malgun Gothic", sans-serif;
}

:root {
  scroll-behavior: auto;
}

section, header {
  scroll-margin-top: 70px;
}

.accent {
  color: var(--accent);
}

.i18n-pending body {
  visibility: hidden;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
  background-color: rgba(0, 0, 0, 0.2);
}

.lang-btn {
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  padding: 5px 12px;
  cursor: pointer;
  transition: color 0.2s, background-color 0.2s;
}

.lang-btn:hover {
  color: var(--text);
}

.lang-btn.active {
  background-color: var(--accent);
  color: #0d1117;
}

.site-navbar {
  background-color: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid transparent;
  padding-top: 14px;
  padding-bottom: 14px;
  transition: padding 0.3s, background-color 0.3s, border-color 0.3s;
}

.site-navbar.scrolled {
  background-color: rgba(13, 17, 23, 0.95);
  border-bottom-color: var(--border);
  padding-top: 8px;
  padding-bottom: 8px;
}

.site-navbar .navbar-brand {
  color: var(--accent);
}

.site-navbar .nav-link {
  color: var(--text-muted);
  transition: color 0.2s;
}

.site-navbar .nav-link:hover,
.site-navbar .nav-link.active {
  color: var(--accent);
}

.navbar-toggler {
  border-color: var(--border);
}
.navbar-toggler-icon {

  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba(230, 237, 243, 0.8)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

.hero {
  min-height: 100vh;

  background:
    radial-gradient(ellipse 60% 40% at 50% 0%, rgba(74, 222, 128, 0.12), transparent),
    var(--bg);

  position: relative;
  overflow: hidden;
}

.hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;

  pointer-events: none;

  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-tagline {
  color: var(--accent);
  letter-spacing: 0.3em;
  font-size: 0.85rem;
  font-weight: 600;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.3;
}

.hero-sub {
  color: var(--text-muted);
  font-size: 1.1rem;
}

.btn-accent {
  background-color: var(--accent);
  border-color: var(--accent);
  color: #0d1117;
  font-weight: 600;
}
.btn-accent:hover {
  background-color: #22c55e;
  border-color: #22c55e;
  color: #0d1117;
}

.section {
  padding: 100px 0;
}

.section-alt {
  background-color: var(--bg-alt);
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.section-desc {
  color: var(--text-muted);
  margin-bottom: 3rem;
}

.profile-photo {

  aspect-ratio: 3 / 4;

  width: 100%;
  max-width: 200px;

  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  background-color: var(--card-bg);
}

.profile-photo img {
  width: 100%;
  height: 100%;

  object-fit: cover;

  object-position: center top;

  display: block;
}

@media (max-width: 991.98px) {
  .profile-photo {
    max-width: 180px;
  }
}

.cred-list {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
}

.cred-item {

  border-left: 2px solid var(--border);
  padding-left: 16px;
  padding-bottom: 20px;
}

.cred-item:last-child {
  padding-bottom: 0;
}

.cred-item:hover {
  border-left-color: var(--accent);
}

.cred-period {
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.15rem;
}

.cred-title {
  font-size: 1rem;
  margin-bottom: 0.15rem;
}

.cred-org {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 0.35rem;
}

.cred-desc {
  color: var(--text-muted);
  font-size: 0.92rem;
  margin-bottom: 0;
}

.cred-list-compact .cred-item {
  padding-bottom: 14px;
}

.award-item {
  height: 100%;
  padding-bottom: 0;
}

.award-head {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 0.15rem;
}

.award-scope {
  margin-left: auto;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text-muted);
  font-size: 0.72rem;
  padding: 1px 9px;
  white-space: nowrap;
}

.award-rank {
  background-color: var(--accent);
  border-radius: 5px;
  color: var(--bg);
  font-size: 0.78rem;
  font-weight: 700;
  margin-right: 7px;
  padding: 2px 8px;

  display: inline-block;
  vertical-align: middle;
}

.award-division {
  color: var(--text-muted);
  font-size: 0.82rem;
  font-weight: 400;
  margin-left: 7px;

  white-space: nowrap;
}

.award-meta {
  color: var(--text-muted);
  font-size: 0.88rem;
  line-height: 1.5;
  margin-bottom: 0.2rem;
}

.award-label {
  color: var(--text);
  display: inline-block;
  font-size: 0.78rem;
  margin-right: 8px;
  min-width: 58px;
  opacity: 0.75;
}

.cred-group + .cred-group {
  margin-top: 2.2rem;
}

.js-anim .cred-hidden {
  display: none;
}

.js-anim #activityList.expanded .cred-hidden {
  display: block;

  animation: credFadeIn 0.35s ease both;
}

.activity-more {
  display: none;
}

.js-anim .activity-more {
  display: block;
}

@keyframes credFadeIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

#activityToggle .bi-chevron-down {
  transition: transform 0.25s ease;
}

#activityToggle[aria-expanded="true"] .bi-chevron-down {
  transform: rotate(180deg);
}

@media (prefers-reduced-motion: reduce) {
  .js-anim #activityList.expanded .cred-hidden {
    animation: none;
  }
  #activityToggle .bi-chevron-down {
    transition: none;
  }
}

.timeline {
  list-style: none;
  padding-left: 0;
  position: relative;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 4px;
  bottom: 4px;
  width: 2px;
  background-color: var(--border);
}

.timeline-item {
  position: relative;
  padding-left: 32px;
  padding-bottom: 28px;
}
.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background-color: var(--bg);
  border: 3px solid var(--accent);
}

.timeline-date {
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
}

.timeline-item p {
  color: var(--text-muted);
  margin-bottom: 0;
  font-size: 0.95rem;
}

.stack-group + .stack-group {
  margin-top: 1rem;
}

.stack-label {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

.tech-badge {
  background-color: var(--card-bg);
  border: 1px solid var(--border);
  color: var(--text);
  font-weight: 500;
  font-size: 0.85rem;
  padding: 0.45em 0.8em;
  margin: 0 0.25rem 0.25rem 0;
}

.filter-btn {
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 6px 18px;
  margin: 0 8px 8px 0;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s, background-color 0.2s;
}

.filter-btn:hover {
  color: var(--text);
  border-color: var(--text-muted);
}

.filter-btn.active {
  background-color: var(--accent);
  border-color: var(--accent);
  color: #0d1117;
  font-weight: 600;
}

.project-item {
  transition: opacity 0.3s ease;
}

.project-item.is-hiding {
  opacity: 0;
  transition: opacity 0.2s ease;
}

.project-item.is-hidden {
  display: none;
}

.project-card {
  background-color: var(--card-bg);
  border: 1px solid var(--border);
  color: var(--text);
  overflow: hidden;
  transition: transform 0.2s, border-color 0.2s;
}

.project-card:hover {
  transform: translateY(-5px);
  border-color: var(--accent);
}

.thumb {
  height: 180px;
}

.thumb-1 { background: linear-gradient(135deg, #1e3a5f, #2d1e5f); }
.thumb-3 { background: linear-gradient(135deg, #1e5f4a, #1e3a5f); }

.thumb-icon {
  font-size: 3rem;
  color: rgba(230, 237, 243, 0.35);
}

.project-meta {
  color: var(--accent);
  font-size: 0.8rem;
  margin-bottom: 0.5rem;
}

.project-card .card-text {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.project-card .card-footer {
  background-color: transparent;
  border-top: 1px solid var(--border);
}

.project-detail {
  padding-top: 140px;
}

.project-description {
  color: var(--text-muted);
  line-height: 1.8;
  white-space: pre-line;
}

.blog-card {
  background-color: var(--card-bg);
  border: 1px solid var(--border);
  color: var(--text);
  transition: transform 0.2s, border-color 0.2s;
}

.blog-card:hover {
  transform: translateY(-5px);
  border-color: var(--accent);
  color: var(--text);
}

.blog-date {
  color: var(--accent);
  font-size: 0.8rem;
  margin-bottom: 0.5rem;
}

.blog-card .card-text {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.contact-links a {
  color: var(--text-muted);
  font-size: 2rem;
  transition: color 0.2s, transform 0.2s;
}

.contact-links a:hover {
  color: var(--accent);
  transform: translateY(-3px);
}

.contact-links a {
  cursor: pointer;
}

.contact-email {
  display: none;
  margin-top: 1.75rem;
}

.js-anim .contact-email {
  display: block;
}

.contact-email a {
  border-bottom: 1px solid var(--border);
  color: var(--text);
  font-size: 1.05rem;
  letter-spacing: 0.01em;
  padding-bottom: 3px;
  text-decoration: none;
  transition: color 0.2s, border-color 0.2s;

  word-break: break-all;
}

.contact-email a:hover {
  border-bottom-color: var(--accent);
  color: var(--accent);
}

.contact-email-fallback {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 1.5rem;
}

.site-footer {
  padding: 30px 0;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.9rem;
}

.visit-counter {
  font-size: 0.8rem;
  color: var(--text-muted);
  opacity: 0.75;
}

.visit-counter strong {
  color: var(--accent);
  font-weight: 600;
}

.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background-color: var(--card-bg);
  color: var(--text);
  font-size: 1.1rem;
  cursor: pointer;
  z-index: 1030;

  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s, background-color 0.2s;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background-color: var(--accent);
  border-color: var(--accent);
  color: #0d1117;
}

.js-anim .reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.js-anim .reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }

  .js-anim .reveal {
    opacity: 1;
    transform: none;
  }
}