/* ==========================================================================
   일타 (Ilta) Landing Page Styles
   Material Design 3 기반
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Variables (MD3 Color System)
   -------------------------------------------------------------------------- */
:root {
  /* Primary */
  --md-primary: #006879;
  --md-on-primary: #FFFFFF;
  --md-primary-container: #A5D7E2;
  --md-on-primary-container: #001F25;

  /* Secondary */
  --md-secondary: #2DD4BF;
  --md-on-secondary: #00201C;

  /* Tertiary */
  --md-tertiary: #F59E0B;
  --md-on-tertiary: #1F1300;

  /* Surface */
  --md-surface: #F8FAFC;
  --md-on-surface: #191C1D;
  --md-on-surface-variant: #3F484A;
  --md-surface-container: #ECEEF0;
  --md-surface-container-high: #E6E8EA;

  /* Outline */
  --md-outline: #6F797B;
  --md-outline-variant: #BFC8CA;

  /* Typography */
  --font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-xxl: 48px;
  --spacing-xxxl: 64px;

  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 28px;
  --radius-button: 20px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  background-color: var(--md-surface);
  color: var(--md-on-surface);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  text-decoration: none;
  color: inherit;
}

/* --------------------------------------------------------------------------
   Typography
   -------------------------------------------------------------------------- */
.display-large {
  font-size: 3rem;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.headline-large {
  font-size: 2rem;
  font-weight: 600;
  line-height: 1.2;
}

.headline-medium {
  font-size: 1.75rem;
  font-weight: 600;
  line-height: 1.3;
}

.title-large {
  font-size: 1.375rem;
  font-weight: 600;
  line-height: 1.4;
}

.body-large {
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.6;
}

.body-medium {
  font-size: 0.875rem;
  font-weight: 400;
  line-height: 1.5;
}

.label-large {
  font-size: 0.875rem;
  font-weight: 500;
  line-height: 1.4;
}

/* --------------------------------------------------------------------------
   Layout
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

section {
  padding: var(--spacing-xxxl) 0;
}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--radius-button);
  font-family: var(--font-family);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all 0.2s ease;
}

.btn--primary {
  background-color: var(--md-primary);
  color: var(--md-on-primary);
}

.btn--primary:hover {
  background-color: #005566;
  box-shadow: var(--shadow-md);
}

.btn--large {
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: 1.125rem;
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(180deg, #E8F4F6 0%, var(--md-surface) 100%);
  padding: var(--spacing-xxl) 0;
}

.hero__content {
  text-align: center;
  max-width: 600px;
}

.hero__icon {
  width: 100px;
  height: 100px;
  margin: 0 auto var(--spacing-lg);
  background: var(--md-primary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
}

.hero__icon svg {
  width: 60px;
  height: 60px;
}

.hero__title {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--md-on-surface);
  margin-bottom: var(--spacing-sm);
}

.hero__tagline {
  font-size: 1.5rem;
  font-weight: 500;
  color: var(--md-on-surface);
  margin-bottom: var(--spacing-sm);
}

.hero__subtitle {
  font-size: 1.125rem;
  color: var(--md-on-surface-variant);
  margin-bottom: var(--spacing-xl);
}

.hero__cta {
  margin-bottom: var(--spacing-lg);
}

.hero__stores {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
}

.hero__stores a {
  transition: transform 0.2s ease;
}

.hero__stores a:hover {
  transform: scale(1.05);
}

.hero__stores img {
  height: 44px;
  width: auto;
}

/* --------------------------------------------------------------------------
   Features Section
   -------------------------------------------------------------------------- */
.features {
  background-color: var(--md-surface);
}

.features__header {
  text-align: center;
  margin-bottom: var(--spacing-xxl);
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: var(--spacing-lg);
}

.feature-card {
  background: var(--md-surface-container);
  border-radius: var(--radius-md);
  padding: var(--spacing-xl);
  text-align: center;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.feature-card__icon {
  width: 64px;
  height: 64px;
  margin: 0 auto var(--spacing-md);
  background: var(--md-primary-container);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.feature-card__icon svg {
  width: 32px;
  height: 32px;
  color: var(--md-primary);
}

.feature-card__title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--md-on-surface);
  margin-bottom: var(--spacing-sm);
}

.feature-card__description {
  font-size: 1rem;
  color: var(--md-on-surface-variant);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   How It Works Section
   -------------------------------------------------------------------------- */
.how-it-works {
  background: linear-gradient(180deg, var(--md-surface) 0%, #E8F4F6 100%);
}

.how-it-works__header {
  text-align: center;
  margin-bottom: var(--spacing-xxl);
}

.steps {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: var(--spacing-xl);
}

.step {
  text-align: center;
}

.step__number {
  width: 40px;
  height: 40px;
  margin: 0 auto var(--spacing-md);
  background: var(--md-primary);
  color: var(--md-on-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 700;
}

.step__screenshot {
  position: relative;
  max-width: 220px;
  margin: 0 auto var(--spacing-md);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background: #fff;
}

.step__screenshot img {
  width: 100%;
  height: auto;
}

.step__title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--md-on-surface);
  margin-bottom: var(--spacing-xs);
}

.step__description {
  font-size: 1rem;
  color: var(--md-on-surface-variant);
}

/* --------------------------------------------------------------------------
   Download CTA Section
   -------------------------------------------------------------------------- */
.download-cta {
  background: var(--md-primary);
  color: var(--md-on-primary);
  text-align: center;
}

.download-cta__title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
}

.download-cta__subtitle {
  font-size: 1.125rem;
  opacity: 0.9;
  margin-bottom: var(--spacing-xl);
}

.download-cta__badges {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
}

.download-cta__badges a {
  transition: transform 0.2s ease;
}

.download-cta__badges a:hover {
  transform: scale(1.05);
}

.download-cta__badges img {
  height: 48px;
  width: auto;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.footer {
  background: var(--md-surface-container);
  padding: var(--spacing-xl) 0;
  text-align: center;
}

.footer__links {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  margin-bottom: var(--spacing-md);
}

.footer__links a {
  color: var(--md-on-surface-variant);
  font-size: 0.875rem;
  transition: color 0.2s ease;
}

.footer__links a:hover {
  color: var(--md-primary);
}

.footer__contact {
  color: var(--md-on-surface-variant);
  font-size: 0.875rem;
  margin-bottom: var(--spacing-sm);
}

.footer__copyright {
  color: var(--md-outline);
  font-size: 0.75rem;
}

/* --------------------------------------------------------------------------
   Responsive - Tablet
   -------------------------------------------------------------------------- */
@media (min-width: 768px) {
  .features__grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .steps {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
  }

  .hero__title {
    font-size: 4rem;
  }

  .hero__tagline {
    font-size: 1.75rem;
  }
}

/* --------------------------------------------------------------------------
   Responsive - Desktop
   -------------------------------------------------------------------------- */
@media (min-width: 1024px) {
  section {
    padding: var(--spacing-xxxl) 0;
  }

  .container {
    padding: 0 var(--spacing-xl);
  }

  .hero__icon {
    width: 120px;
    height: 120px;
  }

  .hero__icon svg {
    width: 72px;
    height: 72px;
  }

  .step__screenshot {
    max-width: 260px;
  }
}