/* ==========================================================================
   1. Reset
   ========================================================================== */

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

/* ==========================================================================
   2. Custom Properties
   ========================================================================== */

:root {
  --color-primary: #2563EB;
  --color-primary-dark: #1D4ED8;
  --color-primary-light: #DBEAFE;
  --color-accent: #2563EB;
  --color-text: #1E293B;
  --color-text-secondary: #64748B;
  --color-bg: #FFFFFF;
  --color-bg-alt: #F8FAFC;
  --color-border: #E2E8F0;
  --color-success: #16A34A;
  --color-success-light: #DCFCE7;
  --color-danger: #DC2626;
  --color-danger-light: #FEE2E2;
  --color-warning: #F59E0B;
  --color-warning-light: #FEF3C7;

  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
  --font-size-base: 1rem;
  --font-size-sm: 0.875rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;

  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  --spacing-4xl: 6rem;

  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);

  --header-height: 4rem;
}

/* ==========================================================================
   3. Base Typography
   ========================================================================== */

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3 {
  line-height: 1.2;
  font-weight: 700;
  color: var(--color-text);
}

h1 {
  font-size: clamp(2rem, 5vw, 3rem);
}

h2 {
  font-size: clamp(1.5rem, 4vw, 2.25rem);
}

h3 {
  font-size: var(--font-size-xl);
}

a {
  color: var(--color-primary-dark);
  text-decoration: none;
  transition: color 0.2s;
}

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

p {
  color: var(--color-text-secondary);
}

ul {
  list-style: none;
}

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

/* ==========================================================================
   4. Utilities
   ========================================================================== */

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  padding: var(--spacing-xs) var(--spacing-md);
  background: var(--color-primary);
  color: #fff;
  border-radius: var(--radius-sm);
  z-index: 1000;
  font-weight: 500;
}

.skip-link:focus {
  top: 0.5rem;
  color: #fff;
}

.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;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  padding: 0.75rem 1.5rem;
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: 600;
  line-height: 1;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s, box-shadow 0.2s;
  text-decoration: none;
  white-space: nowrap;
}

.btn:active {
  transform: scale(0.98);
}

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

.btn--primary:hover {
  background-color: var(--color-primary-dark);
  color: #fff;
}

.btn--accent {
  background-color: var(--color-primary);
  color: #fff;
  padding: 1rem 2rem;
  font-size: var(--font-size-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.btn--accent:hover {
  background-color: var(--color-primary-dark);
  color: #fff;
  box-shadow: var(--shadow-lg);
}

/* ==========================================================================
   5. Header & Nav
   ========================================================================== */

.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: var(--spacing-lg);
}

.header__logo {
  flex-shrink: 0;
}

.header__logo img {
  height: 27px;
  width: auto;
  display: block;
}

.nav__list {
  display: flex;
  gap: var(--spacing-lg);
}

.nav__link {
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color 0.2s;
  padding: var(--spacing-xs) 0;
}

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

.header__cta {
  padding: 0.5rem 1rem;
  font-size: var(--font-size-sm);
}

.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-text);
  padding: var(--spacing-xs);
}

/* Mobile nav */
@media (max-width: 639px) {
  .nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-top: var(--spacing-3xl);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
  }

  .nav--open {
    opacity: 1;
    visibility: visible;
  }

  .nav__list {
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xl);
  }

  .nav__link {
    font-size: var(--font-size-xl);
  }

  .header__cta {
    display: none;
  }

  .hamburger {
    display: block;
  }
}

/* ==========================================================================
   6. Sections
   ========================================================================== */

/* --- Hero --- */
.hero {
  padding: var(--spacing-4xl) 0 var(--spacing-3xl);
  background: linear-gradient(180deg, var(--color-primary-light) 0%, var(--color-bg) 100%);
}

.hero__inner {
  text-align: center;
  max-width: 800px;
}

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

.hero__subtitle {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

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

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

/* --- Generic section --- */
.section {
  padding: var(--spacing-3xl) 0;
}

.section:nth-child(even) {
  background-color: var(--color-bg-alt);
}

.section__title {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

/* --- Cards --- */
.cards {
  display: grid;
  gap: var(--spacing-lg);
}

.cards--3 {
  grid-template-columns: 1fr;
}

.cards--4 {
  grid-template-columns: 1fr;
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  transition: box-shadow 0.3s, transform 0.2s;
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background-color: var(--color-bg-alt);
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-md);
}

.card__icon--accent {
  background-color: var(--color-primary-light);
  color: var(--color-primary);
}

.card__title {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-xs);
}

.card__text {
  font-size: var(--font-size-sm);
}

/* --- Audience --- */
.audience__grid {
  display: grid;
  gap: var(--spacing-lg);
}

.audience__col {
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  border: 1px solid var(--color-border);
}

.audience__col--yes {
  background-color: var(--color-success-light);
  border-color: var(--color-success);
}

.audience__col--no {
  background-color: var(--color-danger-light);
  border-color: var(--color-danger);
}

.audience__heading {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-lg);
  font-size: var(--font-size-xl);
}

.audience__col--yes .audience__heading {
  color: var(--color-success);
}

.audience__col--no .audience__heading {
  color: var(--color-danger);
}

.audience__list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.audience__list li {
  position: relative;
  padding-left: var(--spacing-lg);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  line-height: 1.5;
}

.audience__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.45em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
}

.audience__col--yes .audience__list li::before {
  background-color: var(--color-success);
}

.audience__col--no .audience__list li::before {
  background-color: var(--color-danger);
}

/* --- Timeline / Roadmap --- */
.timeline {
  position: relative;
  max-width: 600px;
  margin: 0 auto;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0.4375rem;
  top: 0.5rem;
  bottom: 0.5rem;
  width: 2px;
  background-color: var(--color-border);
}

.timeline__item {
  position: relative;
  padding-bottom: var(--spacing-xl);
}

.timeline__item:last-child {
  padding-bottom: 0;
}

.timeline__marker {
  position: absolute;
  left: -2rem;
  top: 0.25rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid var(--color-border);
  background: var(--color-bg);
  z-index: 1;
}

.timeline__item--done .timeline__marker {
  background: var(--color-success);
  border-color: var(--color-success);
}

.timeline__item--active .timeline__marker {
  background: var(--color-primary);
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-light);
}

.timeline__label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.25rem;
  display: block;
}

.timeline__item--done .timeline__label {
  color: var(--color-success);
}

.timeline__item--active .timeline__label {
  color: var(--color-primary);
}

.timeline__label:not(.timeline__item--done .timeline__label):not(.timeline__item--active .timeline__label) {
  color: var(--color-text-secondary);
}

.timeline__title {
  font-size: var(--font-size-lg);
  margin-bottom: 0.25rem;
}

.timeline__text {
  font-size: var(--font-size-sm);
}

/* --- CTA --- */
.cta {
  background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-primary-light) 100%);
}

.cta__inner {
  text-align: center;
  max-width: 700px;
}

.cta__subtitle {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-xl);
}

.cta__form {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
}

.cta__form iframe {
  border: none;
  display: block;
}

/* --- Footer --- */
.footer {
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
}

.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
}

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

.footer__link {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

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

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

/* ==========================================================================
   7. Animations
   ========================================================================== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  opacity: 0;
  transform: translateY(20px);
}

.fade-in--visible {
  animation: fadeInUp 0.6s ease forwards;
}

/* ==========================================================================
   8. Media Queries
   ========================================================================== */

@media (min-width: 640px) {
  .cards--3 {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  }

  .cards--4 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  }

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

  .hero {
    padding: var(--spacing-4xl) 0;
  }

  .section {
    padding: var(--spacing-4xl) 0;
  }
}

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

  .cards--4 {
    grid-template-columns: repeat(4, 1fr);
  }

  .nav__list {
    gap: var(--spacing-xl);
  }
}

/* ==========================================================================
   9. Reduced Motion
   ========================================================================== */

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

  .fade-in {
    opacity: 1;
    transform: none;
  }
}