/* ===========================
   PDCS Landing — Base Styles
   =========================== */

:root {
  /* Colors */
  --color-primary: #1a365d;
  --color-primary-light: #2a4a7f;
  --color-accent: #2b6cb0;
  --color-accent-light: #3182ce;
  --color-bg: #ffffff;
  --color-bg-alt: #f7fafc;
  --color-bg-dark: #0f1b2d;
  --color-text: #1a202c;
  --color-text-secondary: #4a5568;
  --color-text-light: #e2e8f0;
  --color-border: #e2e8f0;
  --color-success: #276749;
  --color-success-light: #c6f6d5;
  --color-danger: #c53030;
  --color-danger-light: #fed7d7;
  --color-warning: #d69e2e;
  --color-warning-light: #fefcbf;

  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 2rem;
  --space-xl: 4rem;
  --space-2xl: 6rem;

  /* Layout */
  --max-width: 1200px;
  --border-radius: 8px;
}

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

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

body {
  font-family: var(--font-primary);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
}

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

a:hover {
  color: var(--color-accent-light);
}

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

/* ===========================
   Utilities
   =========================== */

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.section {
  padding: var(--space-2xl) 0;
}

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

.section__title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--space-md);
  color: var(--color-primary);
}

.section__subtitle {
  font-size: 1.05rem;
  color: var(--color-text-secondary);
  text-align: center;
  max-width: 700px;
  margin: 0 auto var(--space-xl);
}

/* ===========================
   Header
   =========================== */

.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-md) 0;
}

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

.header__logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.05em;
}

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

.header__link {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color 0.2s;
}

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

.header__burger {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

.header__burger span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-primary);
  transition: all 0.3s;
}

.lang-switch {
  display: flex;
  gap: var(--space-xs);
  margin-left: var(--space-md);
}

.lang-switch__btn {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: var(--space-xs) var(--space-sm);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--color-text-secondary);
  transition: all 0.2s;
}

.lang-switch__btn--active {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

/* ===========================
   Hero
   =========================== */

.hero {
  padding: var(--space-2xl) 0 var(--space-xl);
  text-align: center;
  background: linear-gradient(180deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
}

.hero__badge {
  display: inline-block;
  padding: var(--space-xs) var(--space-md);
  background-color: #ebf4ff;
  color: var(--color-accent);
  font-size: 0.8125rem;
  font-weight: 600;
  border-radius: 20px;
  margin-bottom: var(--space-lg);
}

.hero__title {
  font-size: 2.75rem;
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: var(--space-md);
  line-height: 1.15;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.hero__subtitle {
  font-size: 1.125rem;
  color: var(--color-text);
  max-width: 720px;
  margin: 0 auto var(--space-lg);
  line-height: 1.7;
  padding: var(--space-md) var(--space-lg);
  background: linear-gradient(135deg, #ebf4ff 0%, #f0f7ff 100%);
  border: 1px solid rgba(43, 108, 176, 0.18);
  border-radius: var(--border-radius);
  box-shadow: 0 4px 20px rgba(26, 54, 93, 0.06);
}

.hero__highlight {
  color: var(--color-accent);
  font-weight: 700;
}

.hero__actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  margin-bottom: var(--space-xl);
  flex-wrap: wrap;
}

.hero__cta {
  display: inline-block;
  background-color: var(--color-accent);
  color: #fff;
  padding: 0.875rem var(--space-lg);
  border-radius: var(--border-radius);
  font-size: 1rem;
  font-weight: 600;
  transition: background-color 0.2s;
}

.hero__cta:hover {
  background-color: var(--color-accent-light);
  color: #fff;
}

.hero__stats {
  display: flex;
  justify-content: center;
  gap: var(--space-xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
  max-width: 600px;
  margin: 0 auto;
}

.hero__stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hero__stat-value {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-primary);
}

.hero__stat-label {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  margin-top: var(--space-xs);
}

/* ===========================
   Advantages
   =========================== */

.advantages__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.advantage-card {
  padding: var(--space-lg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  background-color: var(--color-bg);
  transition: box-shadow 0.2s;
}

.advantage-card:hover {
  box-shadow: 0 4px 20px rgba(26, 54, 93, 0.08);
}

.advantage-card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #ebf4ff;
  border-radius: 10px;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
}

.advantage-card__title {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--color-primary);
}

.advantage-card__text {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ===========================
   Comparison Table
   =========================== */

.comparison__table-wrap {
  overflow-x: auto;
}

.comparison__table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
}

.comparison__table th,
.comparison__table td {
  padding: 0.875rem var(--space-md);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.comparison__table thead th {
  font-weight: 700;
  color: var(--color-primary);
  font-size: 0.9375rem;
  background-color: var(--color-bg-alt);
}

.comparison__table tbody td:first-child {
  font-weight: 500;
  color: var(--color-text);
}

.comparison__highlight {
  background-color: #f0f7ff;
}

.comparison__yes {
  color: var(--color-success);
  font-weight: 600;
}

.comparison__no {
  color: var(--color-danger);
}

/* ===========================
   Architecture / How it works
   =========================== */

.architecture__flow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
  flex-wrap: wrap;
}

.architecture__node {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-lg) var(--space-md);
  border-radius: var(--border-radius);
  border: 2px solid var(--color-border);
  background-color: var(--color-bg);
  min-width: 140px;
  text-align: center;
}

.architecture__node--pdcs {
  border-color: var(--color-accent);
  background-color: #f0f7ff;
}

.architecture__node-icon {
  margin-bottom: var(--space-sm);
  color: var(--color-accent);
}

.architecture__node-title {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--color-primary);
}

.architecture__node-desc {
  font-size: 0.75rem;
  color: var(--color-text-secondary);
  margin-top: 2px;
}

.architecture__arrow {
  color: var(--color-accent);
  flex-shrink: 0;
}

.architecture__levels {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  max-width: 700px;
  margin: 0 auto;
}

.architecture__level {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md);
  background-color: var(--color-bg);
  border-radius: var(--border-radius);
  border: 1px solid var(--color-border);
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
}

.architecture__level-badge {
  flex-shrink: 0;
  display: inline-block;
  padding: var(--space-xs) var(--space-sm);
  background-color: var(--color-accent);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  border-radius: 4px;
}

/* ===========================
   Features
   =========================== */

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

.feature-card {
  padding: var(--space-lg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  border-top: 3px solid var(--color-accent);
}

.feature-card__title {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--color-primary);
}

.feature-card__text {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ===========================
   Compliance
   =========================== */

.compliance__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-lg);
}

.compliance-card {
  padding: var(--space-lg);
  border: 2px solid var(--color-primary);
  border-radius: var(--border-radius);
  background-color: var(--color-bg);
}

.compliance-card__standard {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}

.compliance-card__title {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
}

.compliance-card__text {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ===========================
   Contacts
   =========================== */

.contacts__inner {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
}

.contacts__text {
  font-size: 1rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-lg);
  line-height: 1.7;
}

.contacts__list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-md);
  margin: 0 0 var(--space-lg);
  padding: 0;
}

.contacts__item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-md) var(--space-lg);
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  transition: border-color 0.2s, transform 0.2s;
}

.contacts__item:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

.contacts__label {
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

.contacts__link {
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--color-primary);
  white-space: nowrap;
}

.contacts__link:hover {
  color: var(--color-accent);
}

.contacts__company {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
}

/* ===========================
   Footer
   =========================== */

.footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
  text-align: center;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

.footer__inner {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.footer__address {
  font-size: 0.8125rem;
  color: #a0aec0;
}

/* ===========================
   Responsive
   =========================== */

@media (max-width: 1024px) {
  .header__nav {
    gap: var(--space-md);
  }

  .architecture__flow {
    gap: var(--space-xs);
  }

  .architecture__node {
    min-width: 110px;
    padding: var(--space-md) var(--space-sm);
  }
}

@media (max-width: 768px) {
  .header__nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-bg);
    flex-direction: column;
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  }

  .header__nav--open {
    display: flex;
  }

  .header__burger {
    display: flex;
  }

  .lang-switch {
    margin-left: 0;
  }

  .hero__title {
    font-size: 2rem;
  }

  .hero__subtitle {
    font-size: 1.05rem;
  }

  .hero__stats {
    gap: var(--space-lg);
  }

  .hero__stat-value {
    font-size: 1.25rem;
  }

  .advantages__grid,
  .features__grid {
    grid-template-columns: 1fr;
  }

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

  .comparison__table {
    font-size: 0.8125rem;
  }

  .architecture__flow {
    flex-direction: column;
  }

  .architecture__arrow {
    transform: rotate(90deg);
  }

  .section__title {
    font-size: 1.5rem;
  }
}