/* ============================================================================
   Bok — 베이스 스타일 (리셋·레이아웃·공통 컴포넌트)
   ============================================================================ */

/* Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-body);
  font-weight: var(--weight-regular);
  line-height: var(--leading-body);
  letter-spacing: var(--tracking-body);
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  min-height: 100vh;
}

:lang(ko) { word-break: keep-all; overflow-wrap: break-word; }
:lang(en) { word-break: normal; overflow-wrap: break-word; }

img, svg, video { display: block; max-width: 100%; height: auto; }

a {
  color: var(--color-primary-hover);
  text-decoration: none;
  transition: color var(--motion-fast);
}
a:hover { color: var(--color-primary-hover); }

ul, ol { list-style: none; }

button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

/* Layout primitives */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-inline: auto;
  padding-inline: var(--container-padding);
}

.section { padding-block: var(--space-x5l); }
.section--tight { padding-block: var(--space-x4l); }
.section--hero { padding-block: var(--space-hero) var(--space-x6l); }
.section--surface { background: var(--color-surface); }
.section--cta { background: var(--color-primary-well); }

/* Section header */
.section-header {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-x5l);
}

.section-header__eyebrow {
  font-size: var(--text-micro);
  font-weight: var(--weight-semi-bold);
  letter-spacing: var(--tracking-micro);
  color: var(--color-primary-hover);
  text-transform: uppercase;
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-primary);
  width: fit-content;
}

.section-header__title {
  font-family: var(--font-display);
  font-size: var(--text-headline-large);
  font-weight: var(--weight-bold);
  line-height: var(--leading-headline);
  letter-spacing: var(--tracking-headline-large);
  color: var(--color-text-primary);
}

.section-header__subtitle {
  font-size: var(--text-body-large);
  font-weight: var(--weight-regular);
  line-height: var(--leading-body);
  color: var(--color-text-secondary);
  max-width: 52ch;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-x3l);
  border-radius: var(--radius-md);
  font-size: var(--text-body);
  font-weight: var(--weight-semi-bold);
  line-height: var(--leading-compact);
  white-space: nowrap;
  text-decoration: none;
  transition: background var(--motion-fast), color var(--motion-fast), box-shadow var(--motion-fast);
  cursor: pointer;
  border: none;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-on-primary);
  box-shadow: 0 2px 8px rgba(49, 130, 246, 0.3);
}
.btn--primary:hover {
  background: var(--color-primary-hover);
  color: var(--color-on-primary);
  box-shadow: 0 4px 16px rgba(49, 130, 246, 0.35);
}
.btn--primary:active { background: var(--color-primary-pressed); box-shadow: none; }

.btn--ghost {
  background: transparent;
  color: var(--color-text-primary);
  box-shadow: 0 0 0 1px var(--color-border);
}
.btn--ghost:hover {
  background: var(--color-surface-container);
  color: var(--color-text-primary);
}

.btn--lg { padding: var(--space-base) var(--space-x3l); font-size: var(--text-body-large); }
.btn--sm { padding: var(--space-sm) var(--space-lg); font-size: var(--text-body-small); border-radius: var(--radius-sm); }

.chip {
  display: inline-flex;
  align-items: center;
  padding: var(--space-xs) var(--space-md);
  border-radius: var(--radius-full);
  font-size: var(--text-micro);
  font-weight: var(--weight-medium);
  background: var(--color-primary-well);
  color: var(--color-primary);
}

/* Accessibility */
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0;
}

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

:target { scroll-margin-top: calc(var(--header-height) + var(--space-lg)); }

.skip-link {
  position: absolute; top: 0; left: 0; z-index: 200;
  padding: var(--space-md) var(--space-lg);
  background: var(--color-primary); color: var(--color-on-primary);
  font-size: var(--text-body-small); font-weight: var(--weight-semi-bold);
  border-radius: 0 0 var(--radius-sm) 0;
  transform: translateY(-100%); transition: transform var(--motion-fast);
}
.skip-link:focus { transform: translateY(0); color: var(--color-on-primary); }

/* Reveal — progressive enhancement */
.reveal-on .reveal {
  opacity: 0;
  transform: translateY(20px) scale(0.96);
  transform-origin: center top;
  transition: opacity 500ms cubic-bezier(0.22, 0.61, 0.36, 1),
    transform 500ms cubic-bezier(0.22, 0.61, 0.36, 1);
  transition-delay: var(--reveal-delay, 0ms);
}

.reveal-on .reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body.nav-open { overflow: hidden; }