/* ===== 디자인 토큰 ===== */
:root {
  --bg: #ffffff;
  --bg-alt: #f6f7f9;
  --text: #1a1d21;
  --text-muted: #5c6470;
  --border: #e3e6ea;
  --accent: #2f6df6;
  --accent-soft: #e8efff;
  --radius: 14px;
  --max-width: 1080px;
  --shadow: 0 6px 24px rgba(20, 24, 32, .07);
  --font: "Pretendard", -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Malgun Gothic", system-ui, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171b;
    --bg-alt: #1b1f25;
    --text: #eef1f5;
    --text-muted: #a3adba;
    --border: #2a2f37;
    --accent: #6d9bff;
    --accent-soft: #22304d;
    --shadow: 0 6px 24px rgba(0, 0, 0, .35);
  }
}

/* ===== 리셋 ===== */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== 헤더 ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s, box-shadow .2s;
}
.header.is-scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow);
}
.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo { font-weight: 800; letter-spacing: -.02em; font-size: 1.15rem; }
.logo span { color: var(--accent); }

.nav { display: flex; gap: 28px; }
.nav a {
  font-size: .95rem;
  color: var(--text-muted);
  transition: color .15s;
}
.nav a:hover, .nav a.is-active { color: var(--text); }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 22px; height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform .2s, opacity .2s;
}

/* ===== 히어로 ===== */
.hero {
  padding: 120px 0 100px;
  background:
    radial-gradient(600px 300px at 20% 0%, var(--accent-soft), transparent 70%);
}
.hero__hi { color: var(--accent); font-weight: 600; margin-bottom: 12px; }
.hero__title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  line-height: 1.25;
  letter-spacing: -.03em;
  font-weight: 700;
}
.hero__title strong { color: var(--accent); }
.hero__desc { margin-top: 20px; color: var(--text-muted); font-size: 1.05rem; }
.hero__actions { margin-top: 32px; display: flex; gap: 12px; flex-wrap: wrap; }

/* ===== 버튼 ===== */
.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 999px;
  font-weight: 600;
  font-size: .95rem;
  border: 1px solid transparent;
  transition: transform .15s, opacity .15s, background .15s;
}
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: var(--accent); color: #fff; }
.btn--ghost { border-color: var(--border); color: var(--text); }

/* ===== 섹션 공통 ===== */
.section { padding: 96px 0; }
.section--alt { background: var(--bg-alt); }
.section__label {
  font-size: .8rem;
  letter-spacing: .18em;
  font-weight: 700;
  color: var(--accent);
}
.section__title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  letter-spacing: -.02em;
  margin: 8px 0 40px;
}

/* ===== 소개 ===== */
.about { display: grid; grid-template-columns: 280px 1fr; gap: 48px; }
.about__photo-placeholder {
  aspect-ratio: 1 / 1;
  border-radius: var(--radius);
  border: 1px dashed var(--border);
  background: var(--bg-alt);
  display: grid;
  place-items: center;
  color: var(--text-muted);
  font-size: .9rem;
}
.about__text p { color: var(--text-muted); }
.about__list { margin-top: 24px; display: grid; gap: 10px; }
.about__list li { display: flex; gap: 16px; font-size: .95rem; }
.about__list span {
  width: 72px;
  flex: none;
  font-weight: 600;
  color: var(--text);
}

/* ===== 기술 스택 ===== */
.skills {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}
.skill-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}
.skill-card h3 { font-size: 1.05rem; margin-bottom: 14px; }
.skill-card li {
  color: var(--text-muted);
  font-size: .95rem;
  padding: 4px 0;
}

/* ===== 프로젝트 ===== */
.projects {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}
.project-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg);
  transition: transform .2s, box-shadow .2s;
}
.project-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.project-card__thumb {
  aspect-ratio: 16 / 9;
  background: var(--bg-alt);
  display: grid;
  place-items: center;
  color: var(--text-muted);
  font-size: .9rem;
}
.project-card__body { padding: 22px; }
.project-card__body h3 { font-size: 1.1rem; margin-bottom: 8px; }
.project-card__body p { color: var(--text-muted); font-size: .93rem; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0; }
.tags span {
  font-size: .78rem;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 600;
}
.project-card__links { display: flex; gap: 16px; font-size: .9rem; font-weight: 600; }
.project-card__links a { color: var(--accent); }
.project-card__links a:hover { text-decoration: underline; }

/* ===== 연락처 ===== */
.contact { text-align: center; }
.contact__desc { color: var(--text-muted); margin-bottom: 28px; }
.contact__links {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-top: 36px;
  font-size: .95rem;
  color: var(--text-muted);
}
.contact__links a:hover { color: var(--accent); }

/* ===== 푸터 ===== */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-muted);
  font-size: .88rem;
}

/* ===== 스크롤 등장 효과 ===== */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .6s ease, transform .6s ease;
}
.reveal.is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
}

/* ===== 반응형 ===== */
@media (max-width: 768px) {
  .nav {
    position: absolute;
    top: 64px; left: 0; right: 0;
    flex-direction: column;
    gap: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 8px 24px 16px;
    display: none;
  }
  .nav.is-open { display: flex; }
  .nav a { padding: 12px 0; }
  .nav-toggle { display: flex; }
  .hero { padding: 80px 0 64px; }
  .section { padding: 64px 0; }
  .about { grid-template-columns: 1fr; gap: 28px; }
  .about__photo { max-width: 220px; }
}