:root {
  --vk-blue: #0077ff;
  --vk-blue-dark: #005fcc;
  --vk-blue-soft: #e8f2ff;
  --vk-bg: #f5f7fb;
  --vk-surface: #ffffff;
  --vk-surface-soft: #f9fbff;
  --vk-border: #dce5f0;
  --vk-text: #1f2937;
  --vk-muted: #6b7685;
  --vk-success: #3f9f46;
  --vk-warning: #d9822b;
  --vk-danger: #d93d3d;
  --vk-radius: 16px;
  --vk-shadow: 0 18px 48px rgba(0, 40, 90, 0.09);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    linear-gradient(180deg, rgba(232, 242, 255, 0.86) 0, rgba(245, 247, 251, 0) 360px),
    var(--vk-bg);
  color: var(--vk-text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
}

a {
  color: inherit;
}

code {
  padding: 0.12rem 0.42rem;
  border: 1px solid #cbd9ea;
  border-radius: 8px;
  background: #f2f7ff;
  color: #174775;
  font: 0.92em/1.4 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  width: min(1180px, calc(100% - 32px));
  min-height: 72px;
  margin: 16px auto 0;
  padding: 12px 14px;
  border: 1px solid rgba(220, 229, 240, 0.86);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 14px 38px rgba(0, 40, 90, 0.08);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  min-width: 0;
}

.brand-mark {
  display: grid;
  flex: 0 0 auto;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 13px;
  background: linear-gradient(135deg, var(--vk-blue) 0%, #48a2ff 100%);
  color: #fff;
  font-size: 13px;
  font-weight: 850;
  box-shadow: 0 10px 22px rgba(0, 119, 255, 0.22);
}

.brand strong,
.brand small {
  display: block;
}

.brand strong {
  line-height: 1.15;
}

.brand small {
  color: var(--vk-muted);
  font-size: 12px;
}

.site-nav {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 6px;
  flex-wrap: wrap;
}

.site-nav a {
  min-height: 34px;
  padding: 7px 11px;
  border-radius: 10px;
  color: #405166;
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  background: var(--vk-blue-soft);
  color: var(--vk-blue-dark);
  outline: none;
}

main {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(320px, 0.74fr);
  gap: 34px;
  align-items: center;
  min-height: calc(100vh - 104px);
  padding: 52px 0 46px;
}

.hero-copy {
  max-width: 720px;
}

.eyebrow,
.section-kicker {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  margin-bottom: 14px;
  padding: 0 10px;
  border: 1px solid #cfe0f4;
  border-radius: 999px;
  background: #f4f9ff;
  color: var(--vk-blue-dark);
  font-size: 13px;
  font-weight: 750;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 780px;
  margin-bottom: 18px;
  font-size: clamp(38px, 6vw, 74px);
  line-height: 0.98;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 12px;
  font-size: clamp(28px, 3.8vw, 46px);
  line-height: 1.08;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 19px;
  line-height: 1.25;
}

.hero p,
.section-heading p,
.page-hero p,
.final-cta p {
  color: var(--vk-muted);
  font-size: 18px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 26px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 16px;
  border: 1px solid #c7d8eb;
  border-radius: 12px;
  background: #fff;
  color: #25557e;
  font-weight: 750;
  text-decoration: none;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease, transform 0.15s ease;
}

.button:hover,
.button:focus-visible {
  border-color: #a9c8ea;
  background: #f4f9ff;
  outline: none;
}

.button:active {
  transform: translateY(1px);
}

.button-primary {
  border-color: var(--vk-blue);
  background: var(--vk-blue);
  color: #fff;
  box-shadow: 0 10px 24px rgba(0, 119, 255, 0.22);
}

.button-primary:hover,
.button-primary:focus-visible {
  border-color: var(--vk-blue-dark);
  background: var(--vk-blue-dark);
  color: #fff;
}

.hero-meta {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 24px;
  color: var(--vk-muted);
  font-size: 14px;
}

.hero-meta span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 34px;
  padding: 0 11px;
  border: 1px solid var(--vk-border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.72);
}

#status {
  border-color: rgba(63, 159, 70, 0.36);
  background: #edf8ef;
  color: #226f28;
  font-weight: 800;
  box-shadow: 0 8px 22px rgba(63, 159, 70, 0.14);
}

#status:has(.is-waiting) {
  border-color: rgba(217, 130, 43, 0.36);
  background: #fff6ea;
  color: #9b560d;
  box-shadow: 0 8px 22px rgba(217, 130, 43, 0.12);
}

#status:has(.is-error) {
  border-color: rgba(217, 61, 61, 0.36);
  background: #fff0f0;
  color: #a52a2a;
  box-shadow: 0 8px 22px rgba(217, 61, 61, 0.12);
}

.status-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--vk-success);
  box-shadow: 0 0 0 4px rgba(63, 159, 70, 0.2);
}

.status-dot.is-waiting {
  background: var(--vk-warning);
  box-shadow: 0 0 0 3px rgba(217, 130, 43, 0.14);
}

.status-dot.is-error {
  background: var(--vk-danger);
  box-shadow: 0 0 0 3px rgba(217, 61, 61, 0.14);
}

.hero-panel,
.feature-card,
.scenario-item,
.info-card,
.security-card,
.instruction-card,
.final-cta {
  border: 1px solid var(--vk-border);
  border-radius: var(--vk-radius);
  background: var(--vk-surface);
  box-shadow: var(--vk-shadow);
}

.hero-panel {
  padding: 18px;
}

.chat-preview {
  display: grid;
  gap: 12px;
  padding: 18px;
  border-radius: 14px;
  background: #f4f8fd;
}

.chat-row {
  width: fit-content;
  max-width: 90%;
  padding: 11px 13px;
  border: 1px solid #dae6f3;
  border-radius: 14px;
  background: #fff;
  color: #314256;
  font-weight: 650;
}

.chat-row.is-helper {
  justify-self: end;
  border-color: #bfd9f8;
  background: var(--vk-blue-soft);
  color: #174775;
}

.chat-row.is-admin {
  border-color: #d8eadc;
  background: #f1fbf2;
  color: #245d2c;
}

.signal-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 12px;
}

.signal-grid div {
  padding: 12px;
  border: 1px solid var(--vk-border);
  border-radius: 12px;
  background: #fff;
}

.signal-grid span {
  display: block;
  color: var(--vk-muted);
  font-size: 12px;
}

.signal-grid strong {
  display: block;
  margin-top: 3px;
  font-size: 14px;
  line-height: 1.25;
}

.content-section {
  padding: 50px 0;
}

.section-heading {
  max-width: 720px;
  margin-bottom: 22px;
}

.feature-grid,
.knowledge-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.knowledge-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.feature-card,
.scenario-item,
.info-card {
  padding: 20px;
}

.feature-card p,
.scenario-item p,
.info-card p,
.security-points p {
  margin-bottom: 0;
  color: var(--vk-muted);
}

.feature-icon {
  display: inline-grid;
  width: 38px;
  height: 38px;
  place-items: center;
  margin-bottom: 18px;
  border-radius: 12px;
  background: var(--vk-blue-soft);
  color: var(--vk-blue-dark);
  font-size: 13px;
  font-weight: 800;
}

.split-section {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 26px;
  align-items: start;
}

.scenario-list {
  display: grid;
  gap: 12px;
}

.knowledge-section {
  border-top: 1px solid var(--vk-border);
  border-bottom: 1px solid var(--vk-border);
}

.security-card {
  display: grid;
  grid-template-columns: 0.95fr 1.05fr;
  gap: 24px;
  padding: 28px;
  background: linear-gradient(180deg, #ffffff 0%, #f8fbff 100%);
}

.security-points {
  display: grid;
  gap: 12px;
}

.security-points p {
  padding: 14px 16px;
  border: 1px solid var(--vk-border);
  border-radius: 13px;
  background: #fff;
}

.final-cta {
  margin: 46px 0 74px;
  padding: 34px;
  text-align: center;
}

.final-cta .hero-actions {
  justify-content: center;
}

.page-hero {
  max-width: 840px;
  padding: 66px 0 26px;
}

.instruction-layout {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 22px;
  align-items: start;
  padding-bottom: 74px;
}

.step-nav {
  position: sticky;
  top: 106px;
  display: grid;
  gap: 8px;
  padding: 12px;
  border: 1px solid var(--vk-border);
  border-radius: var(--vk-radius);
  background: rgba(255, 255, 255, 0.86);
  box-shadow: 0 12px 34px rgba(0, 40, 90, 0.07);
}

.step-nav a {
  padding: 9px 10px;
  border-radius: 10px;
  color: #405166;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
}

.step-nav a:hover,
.step-nav a:focus-visible {
  background: var(--vk-blue-soft);
  color: var(--vk-blue-dark);
  outline: none;
}

.instruction-content {
  display: grid;
  gap: 16px;
}

.instruction-card {
  padding: 24px;
  scroll-margin-top: 112px;
}

.step-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding-left: 1.4rem;
}

.step-list li {
  padding-left: 4px;
}

.callout {
  margin-top: 20px;
  padding: 15px 16px;
  border: 1px solid #d7e6f7;
  border-radius: 13px;
  background: #f4f9ff;
}

.callout strong {
  display: block;
  margin-bottom: 4px;
  color: #174775;
}

.callout p {
  margin-bottom: 0;
  color: #405166;
}

.callout.is-important {
  border-color: #f2d3af;
  background: #fff8ef;
}

.callout.is-important strong {
  color: #9a5a12;
}

.callout.is-check {
  border-color: #cfe8d4;
  background: #f4fbf5;
}

.callout.is-check strong {
  color: #2d7435;
}

.check-grid {
  display: grid;
  gap: 10px;
}

.check-grid div {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 13px 14px;
  border: 1px solid var(--vk-border);
  border-radius: 12px;
  background: var(--vk-surface-soft);
}

.check-grid span {
  flex: 0 0 auto;
  width: 10px;
  height: 10px;
  margin-top: 7px;
  border-radius: 50%;
  background: var(--vk-success);
}

@media (max-width: 980px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-nav {
    justify-content: flex-start;
  }

  .hero,
  .split-section,
  .security-card,
  .instruction-layout {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    padding-top: 44px;
  }

  .feature-grid,
  .knowledge-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .step-nav {
    position: static;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 620px) {
  .site-header,
  main {
    width: min(100% - 22px, 1180px);
  }

  .site-header {
    margin-top: 10px;
    border-radius: 16px;
  }

  .site-nav {
    width: 100%;
  }

  .site-nav a {
    flex: 1 1 auto;
    text-align: center;
  }

  h1 {
    font-size: 38px;
  }

  h2 {
    font-size: 28px;
  }

  .hero p,
  .section-heading p,
  .page-hero p,
  .final-cta p {
    font-size: 16px;
  }

  .hero-actions,
  .hero-actions .button,
  .button {
    width: 100%;
  }

  .feature-grid,
  .knowledge-grid,
  .signal-grid,
  .step-nav {
    grid-template-columns: 1fr;
  }

  .content-section {
    padding: 36px 0;
  }

  .final-cta,
  .instruction-card,
  .security-card {
    padding: 20px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}