:root {
  --bg: #0a0a0a;
  --bg-soft: #111111;
  --fg: #f5f5f5;
  --fg-dim: #8a8a8a;
  --fg-mute: #555555;
  --border: #1f1f1f;
  --border-strong: #2a2a2a;
  --accent: #ffffff;
  --radius: 14px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --font:
    "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont,
    "Segoe UI", Roboto, sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font);
  font-weight: 400;
  line-height: 1.6;
  letter-spacing: -0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  cursor: default;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s var(--ease);
}

a:hover {
  color: var(--fg);
}

/* ---------- film grain ---------- */
.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.035;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/></filter><rect width='100%' height='100%' filter='url(%23n)' opacity='0.9'/></svg>");
}

/* ---------- nav ---------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 40px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  background: rgba(10, 10, 10, 0.5);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease);
}

.nav.scrolled {
  border-bottom-color: var(--border);
}

.logo {
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
  display: inline-flex;
  gap: 1px;
}

.logo span {
  display: inline-block;
  transition: transform 0.4s var(--ease);
}

.logo:hover span:nth-child(1) { transform: translateY(-3px); }
.logo:hover span:nth-child(2) { transform: translateY(3px); }
.logo:hover span:nth-child(3) { transform: translateY(-3px); }
.logo:hover span:nth-child(4) { transform: translateY(3px); }
.logo:hover span:nth-child(5) { transform: translateY(-3px); }

.nav-links {
  display: flex;
  gap: 28px;
  font-size: 14px;
  color: var(--fg-dim);
}

.nav-links a {
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 100%;
  height: 1px;
  background: var(--fg);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.35s var(--ease);
}

.nav-links a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

/* ---------- hero ---------- */
main {
  position: relative;
  z-index: 2;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 40px;
}

.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 120px 0 80px;
  position: relative;
}

.eyebrow {
  font-size: 13px;
  color: var(--fg-dim);
  letter-spacing: 0.1em;
  text-transform: lowercase;
  margin-bottom: 24px;
}

.title {
  font-size: clamp(72px, 14vw, 200px);
  font-weight: 800;
  line-height: 0.95;
  letter-spacing: -0.04em;
  margin-bottom: 32px;
}

.scramble {
  display: inline-block;
  font-variant-numeric: tabular-nums;
}

.lead {
  font-size: clamp(16px, 1.6vw, 20px);
  color: var(--fg-dim);
  max-width: 520px;
  margin-bottom: 48px;
}

.hero-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn,
.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 22px;
  font-size: 14px;
  font-weight: 500;
  border-radius: 999px;
  transition: all 0.3s var(--ease);
  will-change: transform;
}

.btn {
  background: var(--fg);
  color: var(--bg);
}

.btn:hover {
  background: #e0e0e0;
  color: var(--bg);
}

.btn-ghost {
  border: 1px solid var(--border-strong);
  color: var(--fg);
}

.btn-ghost:hover {
  border-color: var(--fg);
  background: rgba(255, 255, 255, 0.04);
}

.scroll-hint {
  position: absolute;
  bottom: 40px;
  left: 0;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--fg-mute);
}

.scroll-hint .line {
  width: 60px;
  height: 1px;
  background: var(--fg-mute);
  position: relative;
  overflow: hidden;
}

.scroll-hint .line::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--fg);
  animation: scrollLine 2.4s var(--ease) infinite;
}

@keyframes scrollLine {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

/* ---------- sections ---------- */
.about,
.interests,
.projects,
.links {
  padding: 140px 0;
  border-top: 1px solid var(--border);
}

.section-empty {
  font-size: 15px;
  color: var(--fg-mute);
  letter-spacing: -0.01em;
  padding: 20px 0 10px;
}

.section-empty span {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 13px;
  color: var(--fg-dim);
  margin-left: 6px;
  letter-spacing: 0.02em;
}

.section-head {
  display: flex;
  align-items: baseline;
  gap: 20px;
  margin-bottom: 60px;
}

.section-num {
  font-size: 13px;
  color: var(--fg-mute);
  letter-spacing: 0.1em;
  font-variant-numeric: tabular-nums;
}

.section-head h2 {
  font-size: clamp(36px, 5vw, 56px);
  font-weight: 700;
  letter-spacing: -0.03em;
}

/* ---------- about ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 80px;
  align-items: start;
}

.about-text {
  font-size: clamp(18px, 2vw, 24px);
  color: var(--fg);
  line-height: 1.6;
  letter-spacing: -0.015em;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.about-text em {
  font-style: normal;
  color: var(--fg-dim);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.85em;
}

.about-meta {
  list-style: none;
  border-top: 1px solid var(--border);
}

.about-meta li {
  display: flex;
  justify-content: space-between;
  padding: 18px 0;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}

.about-meta li span:first-child {
  color: var(--fg-mute);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-size: 12px;
}

.about-meta a {
  color: var(--fg);
  border-bottom: 1px solid var(--fg-mute);
}

/* ---------- interests ---------- */
.interest-list {
  list-style: none;
  border-top: 1px solid var(--border);
}

.interest {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 40px;
  padding: 36px 8px;
  border-bottom: 1px solid var(--border);
  position: relative;
  transition: background 0.4s var(--ease);
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity 0.7s var(--ease),
    transform 0.7s var(--ease),
    background 0.4s var(--ease);
}

.interest.in {
  opacity: 1;
  transform: none;
}

.interest::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 0;
  background: linear-gradient(
    90deg,
    rgba(255, 255, 255, 0.035),
    transparent 80%
  );
  transition: width 0.5s var(--ease);
  pointer-events: none;
}

.interest:hover::before {
  width: 100%;
}

.interest:hover .interest-num {
  color: var(--fg);
}

.interest-num {
  font-size: 13px;
  font-variant-numeric: tabular-nums;
  color: var(--fg-mute);
  letter-spacing: 0.1em;
  padding-top: 6px;
  transition: color 0.3s var(--ease);
}

.interest-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-width: 720px;
}

.interest-title {
  font-size: clamp(22px, 2.4vw, 30px);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.interest-desc {
  font-size: 15px;
  color: var(--fg-dim);
  line-height: 1.65;
}

.interest-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 4px;
}

.interest-tags span {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 11px;
  letter-spacing: 0.02em;
  color: var(--fg-mute);
  padding: 4px 9px;
  border-radius: 999px;
  border: 1px solid var(--border);
  transition: all 0.3s var(--ease);
}

.interest:hover .interest-tags span {
  border-color: var(--border-strong);
  color: var(--fg-dim);
}

/* ---------- projects ---------- */
.cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.card {
  position: relative;
  padding: 36px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-soft);
  overflow: hidden;
  min-height: 260px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color 0.4s var(--ease), transform 0.4s var(--ease);
  cursor: pointer;
  will-change: transform;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(
    400px circle at var(--cx, 50%) var(--cy, 50%),
    rgba(255, 255, 255, 0.08),
    transparent 50%
  );
  opacity: 0;
  transition: opacity 0.4s var(--ease);
  pointer-events: none;
}

.card:hover {
  border-color: var(--border-strong);
}

.card:hover::before {
  opacity: 1;
}

.card-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.card-status {
  font-size: 11px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  color: var(--fg-dim);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.card-status::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--fg-mute);
}

.card[data-status="live"] .card-status::before {
  background: var(--fg);
  box-shadow: 0 0 10px rgba(255, 255, 255, 0.6);
  animation: pulse 2s var(--ease) infinite;
}

.card[data-status="live"] .card-status {
  color: var(--fg);
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.card-arrow {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--border-strong);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--fg-dim);
  transition: all 0.3s var(--ease);
}

.card:hover .card-arrow {
  background: var(--fg);
  color: var(--bg);
  border-color: var(--fg);
  transform: rotate(-45deg);
}

.card-body {
  margin-top: auto;
}

.card-domain {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 13px;
  color: var(--fg-mute);
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.card-title {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.card-desc {
  font-size: 14px;
  color: var(--fg-dim);
  line-height: 1.55;
}

/* ---------- footer ---------- */
.footer {
  position: relative;
  z-index: 2;
  border-top: 1px solid var(--border);
  padding: 40px;
  margin-top: 60px;
}

.footer-inner {
  max-width: 1180px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  color: var(--fg-mute);
}

.footer-mark {
  font-weight: 700;
  color: var(--fg);
  letter-spacing: 0.02em;
}

.footer a:hover {
  color: var(--fg);
}

.footer-links {
  display: flex;
  gap: 20px;
}

/* ---------- reveal animation ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.9s var(--ease), transform 0.9s var(--ease);
}

[data-reveal].in {
  opacity: 1;
  transform: none;
}

.card {
  opacity: 0;
  transform: translateY(30px);
  transition:
    opacity 0.7s var(--ease),
    transform 0.7s var(--ease),
    border-color 0.4s var(--ease);
}

.card.in {
  opacity: 1;
  transform: none;
}

/* ---------- responsive ---------- */
@media (max-width: 820px) {
  .nav {
    padding: 18px 22px;
  }
  .nav-links {
    gap: 18px;
  }
  main {
    padding: 0 22px;
  }
  .hero {
    padding: 100px 0 60px;
  }
  .about,
  .interests,
  .projects,
  .links {
    padding: 80px 0;
  }
  .interest {
    grid-template-columns: 1fr;
    gap: 14px;
    padding: 28px 4px;
  }
  .interest-num {
    padding-top: 0;
  }
  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .cards {
    grid-template-columns: 1fr;
  }
  .card {
    padding: 28px;
    min-height: 220px;
  }
  .card-title {
    font-size: 24px;
  }
  .footer {
    padding: 30px 22px;
  }
  .footer-inner {
    flex-direction: column;
    gap: 10px;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  [data-reveal],
  .card {
    opacity: 1;
    transform: none;
  }
}