/* ================================================================
   류준영 — 개발자 랜딩페이지
   Design system: DESIGN.md (bootstrapped from Wanted Montage)
   ================================================================ */

:root {
  /* -- color roles (DESIGN.md §2) -- */
  --canvas: #ffffff;
  --surface-subtle: #f8f8f8;
  --heading: #171719;
  --body: #333333;
  --secondary: #858688;
  --hairline: #e8e9ea;
  --primary: #0066ff;
  --on-primary: #ffffff;

  --bg: var(--surface-subtle);
  --card-bg: var(--canvas);

  /* -- radius scale (DESIGN.md §4/§5) -- */
  --radius-control: 8px;
  --radius-card: 12px;
  --radius-menu: 16px;
  --radius-full: 9999px;

  /* -- spacing scale (DESIGN.md tokens) -- */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 14px;
  --space-lg: 20px;
  --space-xl: 40px;

  /* -- control border (DESIGN.md §4 Button) -- */
  --control-border: 1px solid rgba(112, 115, 124, 0.16);
}

:root[data-theme="dark"] {
  --canvas: #161b22;
  --surface-subtle: #0d1117;
  --heading: #e6edf3;
  --body: #c9d1d9;
  --secondary: #8b949e;
  --hairline: #30363d;
  --primary: #58a6ff;
  --on-primary: #0d1117;
  --control-border: 1px solid rgba(139, 148, 158, 0.3);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--body);
  font-family: "Pretendard Variable", -apple-system, BlinkMacSystemFont, "Segoe UI", "Malgun Gothic", sans-serif;
  font-size: 14px;
  line-height: 1.43;
  padding: var(--space-lg);
  transition: background 0.2s, color 0.2s;
}

a {
  color: inherit;
}

/* -- Theme toggle (light default, manual switch — DESIGN.md §4 Button tokens) -- */
.theme-toggle {
  position: fixed;
  top: var(--space-lg);
  right: var(--space-lg);
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-control);
  border: var(--control-border);
  background: var(--canvas);
  color: var(--heading);
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
  background: color-mix(in srgb, var(--heading) 6%, transparent);
  border-color: var(--secondary);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
}

.theme-toggle .icon-moon {
  display: none;
}

:root[data-theme="dark"] .theme-toggle .icon-sun {
  display: none;
}

:root[data-theme="dark"] .theme-toggle .icon-moon {
  display: block;
}

.wrap {
  max-width: 800px;
  margin: var(--space-xl) auto;
  background: var(--card-bg);
  padding: var(--space-xl);
  border-radius: var(--radius-card);
  border: 1px solid var(--hairline);
}

/* -- Hero / profile header -- */
.hero {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  border-bottom: 1px solid var(--hairline);
  padding-bottom: var(--space-xl);
  margin-bottom: var(--space-xl);
}

.hero-avatar {
  width: 110px;
  height: 110px;
  border-radius: var(--radius-full);
  object-fit: cover;
  flex-shrink: 0;
  border: 1px solid var(--hairline);
}

.hero-text .kicker {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--primary);
  margin: 0 0 var(--space-sm);
}

.hero-text h1 {
  margin: 0 0 var(--space-sm);
  font-size: 22px;
  font-weight: 600;
  line-height: 1.36;
  letter-spacing: -0.02em;
  color: var(--heading);
}

.hero-text p.bio {
  margin: 0 0 var(--space-md);
  color: var(--body);
  font-size: 14px;
  line-height: 1.43;
  max-width: 52ch;
}

.links {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

/* -- Button (DESIGN.md §4: transparent, bordered — no filled variant) -- */
.links a {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  height: 32px;
  padding: 7px 14px;
  border-radius: var(--radius-control);
  border: var(--control-border);
  background: transparent;
  color: var(--primary);
  font-size: 14px;
  font-weight: 400;
  transition: background 0.15s, border-color 0.15s;
}

.links a:hover,
.links a:focus-visible {
  background: color-mix(in srgb, var(--primary) 8%, transparent);
  border-color: var(--primary);
}

.links a:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

.links a.btn-secondary {
  height: 36px;
  padding: 7px 11px;
  color: var(--heading);
}

.links a.btn-secondary:hover,
.links a.btn-secondary:focus-visible {
  background: color-mix(in srgb, var(--heading) 6%, transparent);
  border-color: var(--secondary);
}

/* -- Sections -- */
section.block {
  margin-bottom: var(--space-xl);
}

section.block h2 {
  font-size: 22px;
  font-weight: 600;
  line-height: 1.36;
  letter-spacing: -0.02em;
  color: var(--heading);
  border-bottom: 2px solid var(--primary);
  display: inline-block;
  padding-bottom: var(--space-xs);
  margin: 0 0 var(--space-md);
}

/* -- Timeline (career) -- */
.timeline-item {
  display: grid;
  grid-template-columns: 128px 1fr;
  gap: var(--space-md);
  padding: 13px 0;
  border-top: 1px solid var(--hairline);
}

.timeline-item:first-of-type {
  border-top: none;
}

.timeline-item .period {
  color: var(--secondary);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.02em;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  padding-top: 2px;
}

.timeline-item .role {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--heading);
  margin: 0 0 var(--space-xs);
}

.timeline-item .desc {
  color: var(--body);
  font-size: 14px;
  line-height: 1.43;
  margin: 0;
}

/* -- Featured project card (DESIGN.md §4: flat, 12px radius, no shadow) -- */
.project-card {
  background: var(--surface-subtle);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-card);
  padding: var(--space-lg);
}

.project-card h3 {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--heading);
  margin: 0 0 6px;
}

.project-card .tagline {
  color: var(--body);
  font-size: 14px;
  line-height: 1.43;
  margin: 0 0 var(--space-md);
}

.tags {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  margin-bottom: var(--space-md);
}

/* -- Badge / tag / pill (DESIGN.md §4: neutral subtle-surface, full radius) -- */
.tag {
  display: inline-block;
  background: var(--canvas);
  color: var(--secondary);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.02em;
  padding: 5px 12px;
  border-radius: var(--radius-full);
  border: 1px solid var(--hairline);
  text-decoration: none;
  transition: color 0.15s, border-color 0.15s;
}

a.tag:hover,
a.tag:focus-visible {
  color: var(--primary);
  border-color: var(--primary);
}

a.tag:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

.stack-line {
  color: var(--secondary);
  font-size: 12px;
  margin: 0;
}

/* -- Skills -- */
.skill-groups {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--space-lg);
}

.skill-groups h4 {
  margin: 0 0 var(--space-sm);
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--secondary);
}

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.pill {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.02em;
  padding: 5px 12px;
  border-radius: var(--radius-full);
  background: var(--surface-subtle);
  color: var(--heading);
  border: 1px solid var(--hairline);
}

/* -- Education / certs -- */
.simple-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.simple-list li {
  padding: var(--space-sm) 0;
  border-top: 1px solid var(--hairline);
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  font-size: 14px;
  color: var(--heading);
}

.simple-list li:first-child {
  border-top: none;
}

.simple-list .muted {
  color: var(--secondary);
  font-size: 12px;
  white-space: nowrap;
}

/* -- Other projects (lightweight list — DESIGN.md §5: only the featured project gets card treatment) -- */
.project-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.project-list li {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-top: 1px solid var(--hairline);
}

.project-list li:first-child {
  border-top: none;
}

.proj-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--heading);
  margin: 0 0 4px;
}

.proj-desc {
  font-size: 14px;
  line-height: 1.43;
  color: var(--body);
  margin: 0;
  max-width: 48ch;
}

.proj-links {
  display: flex;
  gap: var(--space-sm);
  flex-shrink: 0;
}

footer {
  color: var(--secondary);
  font-size: 12px;
  border-top: 1px solid var(--hairline);
  padding-top: var(--space-lg);
}

@media (max-width: 600px) {
  .wrap {
    padding: var(--space-lg);
    margin: var(--space-lg) auto;
  }
  .hero {
    flex-direction: column;
    text-align: center;
  }
  .hero-text .kicker {
    justify-content: center;
  }
  .links {
    justify-content: center;
  }
  .timeline-item {
    grid-template-columns: 1fr;
    gap: var(--space-xs);
  }
  .simple-list li {
    flex-direction: column;
    gap: 2px;
  }
}