/* ==========================================================================
   CostSplit - Promotional Website Styles
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. CSS Custom Properties (Variables)
   -------------------------------------------------------------------------- */
:root {
  /* Primary Colors */
  --color-primary: #69BD7A;
  --color-primary-light: #E8F5EB;
  --color-primary-dark: #55A866;

  /* Background Colors */
  --color-bg: #FEFFFF;
  --color-bg-alt: #F5F7F6;
  --color-bg-elevated: #FFFFFF;

  /* Text Colors */
  --color-text-primary: #012321;
  --color-text-secondary: #4A6361;
  --color-text-muted: #7A9290;

  /* Border */
  --color-border: #E0E8E7;

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-xxl: 48px;
  --space-3xl: 64px;

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-2xl: 24px;
  --radius-full: 9999px;

  /* Typography */
  --font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-xs: 12px;
  --font-size-sm: 14px;
  --font-size-md: 16px;
  --font-size-lg: 20px;
  --font-size-xl: 24px;
  --font-size-2xl: 32px;
  --font-size-3xl: 40px;
  --font-size-4xl: 48px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;

  /* Container */
  --container-max: 1120px;
  --container-narrow: 800px;
}

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

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

body {
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  min-height: 100vh;
}

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

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

ul, ol {
  list-style: none;
}

/* --------------------------------------------------------------------------
   3. Typography
   -------------------------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: var(--space-md);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }

p { margin-bottom: var(--space-md); }
.text-center { text-align: center; }
.text-muted { color: var(--color-text-secondary); }

/* --------------------------------------------------------------------------
   4. Layout
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container--narrow {
  max-width: var(--container-narrow);
}

.section {
  padding: var(--space-3xl) 0;
}

.section--hero {
  padding: 160px 0 100px;
  text-align: center;
}

.section--page-header {
  padding: calc(var(--space-3xl) + 40px) 0 var(--space-xl);
}

.section--page-header .page-header__breadcrumb {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-sm);
}

.section--page-header .page-header__breadcrumb a {
  color: var(--color-text-muted);
  text-decoration: none;
}

.section--page-header .page-header__breadcrumb a:hover {
  color: var(--color-primary);
}

.section--page-header h1 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-bottom: var(--space-xs);
}

.section--page-header p {
  font-size: var(--font-size-md);
  color: var(--color-text-secondary);
}

/* --------------------------------------------------------------------------
   5. Navigation
   -------------------------------------------------------------------------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-md) 0;
}

.nav__content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.nav__logo span {
  font-weight: 700;
  font-size: var(--font-size-lg);
  color: var(--color-primary);
}

.nav__logo:hover span {
  color: var(--color-primary);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.nav__links a {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  transition: color var(--transition-fast);
}

.nav__links a:hover {
  color: var(--color-text-primary);
}

.nav__cta {
  display: none;
}

@media (min-width: 768px) {
  .nav__cta {
    display: block;
  }
}

.nav__toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-text-primary);
  font-size: 24px;
  cursor: pointer;
}

@media (max-width: 767px) {
  .nav__toggle {
    display: block;
  }

  .nav__links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
  }

  .nav__links.active {
    display: flex;
  }
}

/* --------------------------------------------------------------------------
   6. Buttons
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  font-weight: 600;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
}

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

.btn--primary:hover {
  background: var(--color-primary-dark);
  color: white;
  transform: translateY(-1px);
}

.btn--outline {
  background: white;
  color: var(--color-primary);
  border: 1.5px solid var(--color-primary);
}

.btn--outline:hover {
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}

.btn--large {
  padding: var(--space-md) var(--space-xl);
  font-size: var(--font-size-md);
  border-radius: var(--radius-lg);
}

.btn--small {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-sm);
}

.btn--full {
  width: 100%;
}

.btn-group {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  justify-content: center;
}

/* --------------------------------------------------------------------------
   7. Hero Section
   -------------------------------------------------------------------------- */
.hero__title {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-lg);
}

.hero__subtitle {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 540px;
  margin: 0 auto var(--space-xl);
  line-height: 1.7;
}

/* --------------------------------------------------------------------------
   8. Features Section
   -------------------------------------------------------------------------- */
.features {
  padding: 100px 0;
  background: var(--color-bg-alt);
}

.features h2 {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
  margin-top: var(--space-xxl);
}

.feature-card {
  background: var(--color-bg);
  border-radius: var(--radius-xl);
  border: 1px solid var(--color-border);
  padding: var(--space-xl);
  transition: all var(--transition-normal);
}

.feature-card:hover {
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
  transform: translateY(-4px);
}

.feature-card__icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--color-primary-light);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-md);
}

.feature-card__title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--color-text-primary);
}

.feature-card__description {
  color: var(--color-text-secondary);
  margin-bottom: 0;
  font-size: var(--font-size-sm);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   9. How It Works
   -------------------------------------------------------------------------- */
.how-it-works {
  padding: 100px 0;
}

.how-it-works h2 {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: var(--space-xxl);
  letter-spacing: -0.02em;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xxl);
  text-align: center;
}

.step__number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  color: white;
  font-size: 1.25rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-md);
}

.step h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: var(--space-sm);
}

.step p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  max-width: 280px;
  margin: 0 auto;
}

/* --------------------------------------------------------------------------
   10. Download CTA Section
   -------------------------------------------------------------------------- */
.download-cta {
  padding: 100px 0;
  background: var(--color-bg-alt);
  text-align: center;
}

.download-cta h2 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}

.download-cta p {
  color: var(--color-text-secondary);
  font-size: 1.1rem;
  margin-bottom: var(--space-xl);
}

/* --------------------------------------------------------------------------
   11. Download Modal
   -------------------------------------------------------------------------- */
.modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 2000;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg);
}

.modal-overlay.active {
  display: flex;
}

.modal {
  background: var(--color-bg);
  border-radius: var(--radius-2xl);
  padding: var(--space-xl);
  max-width: 400px;
  width: 100%;
  border: 1px solid var(--color-border);
  position: relative;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.modal--download {
  max-width: 600px;
  text-align: center;
  padding: var(--space-xxl) var(--space-xl);
}

.modal__title {
  font-size: var(--font-size-2xl);
  margin: 0 0 var(--space-sm);
}

.modal__subtitle {
  color: var(--color-text-secondary);
  margin: 0 0 var(--space-xl);
}

.modal__close {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  background: none;
  border: none;
  color: var(--color-text-muted);
  font-size: 28px;
  cursor: pointer;
  padding: var(--space-sm);
  line-height: 1;
}

.modal__close:hover {
  color: var(--color-text-primary);
}

/* Store Badges */
.store-badges {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
}

.store-badge {
  display: block;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.store-badge:hover {
  transform: scale(1.05);
  opacity: 0.9;
}

.store-badge img {
  height: 44px;
  width: auto;
}

.store-badge--web {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  background: #000;
  border: 1px solid #a6a6a6;
  border-radius: 8px;
  color: #fff;
  height: 44px;
  text-decoration: none;
}

.store-badge--web:hover {
  background: #1a1a1a;
}

.store-badge__web-icon {
  font-size: 24px;
}

.store-badge__web-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.store-badge__web-small {
  font-size: 10px;
  font-weight: 400;
}

.store-badge__web-large {
  font-size: 16px;
  font-weight: 600;
}

@media (max-width: 700px) {
  .store-badges {
    flex-direction: column;
    align-items: center;
  }
}

/* --------------------------------------------------------------------------
   12. Forms
   -------------------------------------------------------------------------- */
.form-group {
  margin-bottom: var(--space-lg);
}

.form-group label {
  display: block;
  margin-bottom: var(--space-sm);
  font-weight: 500;
  color: var(--color-text-primary);
}

.form-control {
  width: 100%;
  padding: var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  color: var(--color-text-primary);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition-fast);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
}

.form-control::placeholder {
  color: var(--color-text-muted);
}

textarea.form-control {
  min-height: 150px;
  resize: vertical;
}

select.form-control {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%237A9290' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
  padding-right: 40px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

/* --------------------------------------------------------------------------
   13. FAQ Accordion
   -------------------------------------------------------------------------- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.faq-item {
  border-bottom: 1px solid var(--color-border);
}

.faq-item:last-child {
  border-bottom: none;
}

.faq-item__question {
  width: 100%;
  padding: var(--space-lg) var(--space-sm);
  background: none;
  border: none;
  color: var(--color-text-primary);
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  font-weight: 500;
  text-align: left;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-md);
  transition: color var(--transition-fast);
}

.faq-item__question:hover {
  color: var(--color-primary);
}

.faq-item__icon {
  font-size: 18px;
  color: var(--color-text-muted);
  transition: transform var(--transition-normal), color var(--transition-fast);
  flex-shrink: 0;
}

.faq-item.active .faq-item__icon {
  transform: rotate(45deg);
  color: var(--color-primary);
}

.faq-item__answer {
  display: none;
  padding: 0 var(--space-sm) var(--space-lg);
  color: var(--color-text-secondary);
  line-height: 1.7;
  font-size: var(--font-size-sm);
}

.faq-item.active .faq-item__answer {
  display: block;
}

.faq-item__answer p {
  margin-bottom: var(--space-md);
}

.faq-item__answer p:last-child {
  margin-bottom: 0;
}

.faq-item__answer ul {
  margin: var(--space-md) 0 0 var(--space-lg);
  padding: 0;
}

.faq-item__answer li {
  margin-bottom: var(--space-sm);
  padding-left: var(--space-sm);
  list-style: disc;
}

.faq-item__answer li:last-child {
  margin-bottom: 0;
}

.faq-item__answer strong {
  color: var(--color-text-primary);
}

/* --------------------------------------------------------------------------
   14. Support Page Layout
   -------------------------------------------------------------------------- */
.support-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: start;
  margin-top: var(--space-xl);
}

.support-info h1 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-bottom: var(--space-md);
}

.support-info > p {
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: var(--space-xl);
}

.support-info__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.support-info__link {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: background var(--transition-fast);
}

.support-info__link:hover {
  background: var(--color-bg-alt);
}

.support-info__link-icon {
  width: 40px;
  height: 40px;
  background: var(--color-primary-light);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
}

.support-info__link-label {
  color: var(--color-text-primary);
  font-size: var(--font-size-sm);
  font-weight: 600;
}

.support-info__link-value {
  color: var(--color-text-muted);
  font-size: var(--font-size-xs);
  margin-top: 1px;
}

@media (max-width: 768px) {
  .support-layout {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .form-row {
    grid-template-columns: 1fr;
  }
}

/* --------------------------------------------------------------------------
   15. Footer
   -------------------------------------------------------------------------- */
.footer {
  background: var(--color-bg-alt);
  padding: var(--space-xxl) 0 var(--space-lg);
  border-top: 1px solid var(--color-border);
}

.footer__content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-xl);
  margin-bottom: var(--space-xxl);
}

.footer__brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.footer__brand span {
  font-weight: 700;
  color: var(--color-primary);
}

.footer__description {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.footer__title {
  font-size: var(--font-size-sm);
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-text-primary);
  margin-bottom: var(--space-md);
  font-weight: 600;
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer__links a {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

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

.footer__bottom {
  text-align: center;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
}

/* --------------------------------------------------------------------------
   16. Legal Pages
   -------------------------------------------------------------------------- */
.legal {
  padding-top: 100px;
}

.legal h1 {
  margin-bottom: var(--space-xl);
}

.legal h2 {
  font-size: var(--font-size-xl);
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
  color: var(--color-primary-dark);
}

.legal p, .legal li {
  color: var(--color-text-secondary);
  line-height: 1.8;
}

.legal ul {
  margin-left: var(--space-lg);
  margin-bottom: var(--space-md);
}

.legal li {
  margin-bottom: var(--space-sm);
  list-style: disc;
}

.legal a {
  color: var(--color-primary);
}

.legal a:hover {
  text-decoration: underline;
}

.legal__date {
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
  margin-bottom: var(--space-xl);
}

/* --------------------------------------------------------------------------
   17. Utilities
   -------------------------------------------------------------------------- */
.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--space-sm); }
.mt-2 { margin-top: var(--space-md); }
.mt-3 { margin-top: var(--space-lg); }
.mt-4 { margin-top: var(--space-xl); }
.mt-5 { margin-top: var(--space-xxl); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--space-sm); }
.mb-2 { margin-bottom: var(--space-md); }
.mb-3 { margin-bottom: var(--space-lg); }
.mb-4 { margin-bottom: var(--space-xl); }
.mb-5 { margin-bottom: var(--space-xxl); }

/* --------------------------------------------------------------------------
   18. Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {
  .section--hero {
    padding: 120px 0 80px;
  }

  .hero__title {
    font-size: 2.25rem;
  }

  .hero__subtitle {
    font-size: 1.05rem;
  }

  .features__grid {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  .steps {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .footer__content {
    grid-template-columns: 1fr 1fr;
  }

  h1 { font-size: var(--font-size-2xl); }
  h2 { font-size: var(--font-size-xl); }
}

@media (max-width: 1024px) and (min-width: 769px) {
  .features__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}