/* ==========================================================================
   북막 홈페이지 스타일
   Design Reference: Minimal, Premium, Clean
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Variables
   -------------------------------------------------------------------------- */
:root {
  --color-primary: #7c3aed;
  --color-primary-dark: #6d28d9;
  --color-accent: #dc2626;

  --color-text: #111111;
  --color-text-light: #555555;
  --color-text-muted: #888888;

  --color-bg: #ffffff;
  --color-bg-light: #fafafa;
  --color-border: #e5e5e5;

  --font-sans: 'Pretendard', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-serif: 'Noto Serif KR', Georgia, serif;

  --transition: all 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

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

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

/* --------------------------------------------------------------------------
   Typography
   -------------------------------------------------------------------------- */
h1, h2, h3 {
  font-weight: 400;
  line-height: 1.4;
}

h1 {
  font-size: 2.5rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 2rem;
  letter-spacing: -0.01em;
}

@media (min-width: 768px) {
  h1 {
    font-size: 3.5rem;
  }
  h2 {
    font-size: 2.5rem;
  }
}

@media (min-width: 1024px) {
  h1 {
    font-size: 4rem;
  }
  h2 {
    font-size: 3rem;
  }
}

/* --------------------------------------------------------------------------
   Layout
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
}

@media (min-width: 768px) {
  .container {
    padding: 0 48px;
  }
}

@media (min-width: 1024px) {
  .container {
    padding: 0 64px;
  }
}

/* --------------------------------------------------------------------------
   Header
   -------------------------------------------------------------------------- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

@media (min-width: 768px) {
  .header-inner {
    height: 80px;
  }
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo img {
  height: 32px;
  width: auto;
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.nav-desktop {
  display: none;
}

@media (min-width: 768px) {
  .nav-desktop {
    display: flex;
    align-items: center;
    gap: 40px;
  }
}

.nav-link {
  font-size: 0.875rem;
  color: var(--color-text-light);
  letter-spacing: 0.02em;
}

.nav-link:hover {
  color: var(--color-text);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.btn-start {
  display: none;
  padding: 10px 24px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-bg);
  background: var(--color-text);
  border: none;
  border-radius: 4px;
  cursor: pointer;
  transition: var(--transition);
}

@media (min-width: 768px) {
  .btn-start {
    display: inline-flex;
  }
}

.btn-start:hover {
  background: var(--color-primary);
}

.menu-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  background: none;
  border: none;
  cursor: pointer;
}

@media (min-width: 768px) {
  .menu-toggle {
    display: none;
  }
}

.menu-toggle span {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--color-text);
}

/* Mobile Menu */
.nav-mobile {
  display: none;
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-bg);
  padding: 32px 24px;
  z-index: 999;
}

.nav-mobile.active {
  display: block;
}

.nav-mobile a {
  display: block;
  padding: 16px 0;
  font-size: 1.125rem;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border);
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
  padding: 140px 0 80px;
}

@media (min-width: 768px) {
  .hero {
    padding: 160px 0 100px;
  }
}

.hero-content {
  max-width: 900px;
}

.hero h1 {
  margin-bottom: 32px;
  font-family: var(--font-serif);
  font-weight: 400;
  line-height: 1.5;
}

.hero h1 em {
  font-style: italic;
}

.hero-subtitle {
  font-size: 1rem;
  color: var(--color-text-light);
  max-width: 500px;
  margin-bottom: 40px;
  line-height: 1.8;
}

@media (min-width: 768px) {
  .hero-subtitle {
    font-size: 1.125rem;
  }
}

.hero-cta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-bg);
  background: var(--color-text);
  border: 1px solid var(--color-text);
  border-radius: 4px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-primary:hover {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text);
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  cursor: pointer;
  transition: var(--transition);
}

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

.hero-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 48px;
  padding: 12px 16px;
  background: var(--color-bg-light);
  border-radius: 4px;
  width: fit-content;
}

.hero-badge-icon {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent);
  color: white;
  border-radius: 50%;
  font-size: 0.75rem;
  font-weight: 700;
}

.hero-badge-text {
  font-size: 0.8125rem;
  color: var(--color-text-light);
}

.hero-badge-text strong {
  color: var(--color-text);
}

/* --------------------------------------------------------------------------
   Image Grid Section
   -------------------------------------------------------------------------- */
.image-grid {
  padding: 60px 0;
}

.grid-3 {
  display: grid;
  gap: 16px;
}

@media (min-width: 768px) {
  .grid-3 {
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }
}

.grid-item {
  position: relative;
  aspect-ratio: 4/3;
  overflow: hidden;
  background: var(--color-bg-light);
  border-radius: 8px;
}

.grid-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.grid-item:hover img {
  transform: scale(1.05);
}

.grid-item-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 24px;
  background: linear-gradient(transparent, rgba(0,0,0,0.7));
  color: white;
}

.grid-item-overlay h3 {
  font-size: 1.125rem;
  font-weight: 500;
  margin-bottom: 4px;
}

.grid-item-overlay p {
  font-size: 0.875rem;
  opacity: 0.8;
}

/* --------------------------------------------------------------------------
   Features Section
   -------------------------------------------------------------------------- */
.features {
  padding: 100px 0;
}

.features.bg-light {
  background: var(--color-bg-light);
}

.features-header {
  max-width: 700px;
  margin-bottom: 60px;
}

.features-header h2 {
  font-family: var(--font-serif);
  margin-bottom: 24px;
}

.features-header p {
  font-size: 1rem;
  color: var(--color-text-light);
  line-height: 1.8;
}

.features-grid {
  display: grid;
  gap: 40px;
}

@media (min-width: 768px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 48px;
  }
}

@media (min-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.feature-card {
  padding: 32px;
  background: var(--color-bg-light);
  border-radius: 8px;
  transition: var(--transition);
}

.feature-card:hover {
  background: var(--color-bg);
  box-shadow: 0 8px 30px rgba(0,0,0,0.08);
}

.feature-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
}

.feature-card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-card p {
  font-size: 0.9375rem;
  color: var(--color-text-light);
  line-height: 1.7;
}

.feature-tag {
  display: inline-block;
  margin-top: 16px;
  padding: 4px 10px;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-primary);
  background: rgba(124, 58, 237, 0.1);
  border-radius: 4px;
}

/* --------------------------------------------------------------------------
   Brand Story Section
   -------------------------------------------------------------------------- */
.brand-story {
  padding: 100px 0;
  background: var(--color-bg-light);
}

.brand-story.bg-white {
  background: var(--color-bg);
}

.brand-story-content {
  display: grid;
  gap: 48px;
  align-items: center;
}

@media (min-width: 768px) {
  .brand-story-content {
    grid-template-columns: 1fr 1fr;
    gap: 80px;
  }
}

.brand-story-text h2 {
  font-family: var(--font-serif);
  margin-bottom: 24px;
}

.brand-story-text p {
  font-size: 1rem;
  color: var(--color-text-light);
  line-height: 1.9;
  margin-bottom: 16px;
}

.brand-name-meaning {
  margin-top: 32px;
  padding: 24px;
  background: var(--color-bg);
  border-radius: 8px;
}

.brand-name-meaning h4 {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.brand-name-meaning p {
  font-size: 1rem;
  color: var(--color-text);
  margin-bottom: 0;
}

/* --------------------------------------------------------------------------
   Stats Section
   -------------------------------------------------------------------------- */
.stats {
  padding: 80px 0;
  margin-top: 60px;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  text-align: center;
}

@media (min-width: 768px) {
  .stats-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 48px;
  }
}

.stat-item h3 {
  font-size: 2.5rem;
  font-weight: 300;
  margin-bottom: 8px;
  font-family: var(--font-serif);
}

@media (min-width: 768px) {
  .stat-item h3 {
    font-size: 3rem;
  }
}

.stat-item p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* --------------------------------------------------------------------------
   CTA Section
   -------------------------------------------------------------------------- */
.cta-section {
  padding: 120px 0;
  text-align: center;
  background: var(--color-bg-light);
}

.cta-section h2 {
  font-family: var(--font-serif);
  margin-bottom: 16px;
}

.cta-section p {
  font-size: 1.125rem;
  color: var(--color-text-light);
  margin-bottom: 40px;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.footer {
  padding: 64px 0 32px;
  background: var(--color-text);
  color: var(--color-bg);
}

.footer-content {
  display: grid;
  gap: 40px;
  margin-bottom: 48px;
}

@media (min-width: 768px) {
  .footer-content {
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 64px;
  }
}

.footer-brand p {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.6);
  margin-top: 16px;
  line-height: 1.7;
}

.footer-links h4 {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 20px;
  color: rgba(255,255,255,0.4);
}

.footer-links a {
  display: block;
  font-size: 0.875rem;
  color: rgba(255,255,255,0.7);
  margin-bottom: 12px;
}

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

.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,0.1);
  text-align: center;
}

.footer-bottom p {
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.4);
}

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