/* ===== Design tokens ===== */
:root {
  --color-bg: #0b0d17;
  --color-bg-soft: #11142180;
  --color-surface: #161a2c;
  --color-surface-2: #1c2138;
  --color-border: #262b45;
  --color-text: #f3f5ff;
  --color-text-muted: #9aa3c4;
  --color-accent: #7c5cff;
  --color-accent-2: #4ac8ff;
  --gradient-accent: linear-gradient(135deg, #7c5cff 0%, #4ac8ff 100%);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --shadow-glow: 0 20px 60px -20px rgba(124, 92, 255, 0.45);
  --container: 1140px;
}

/* ===== Base ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  interpolate-size: allow-keywords;
}

.page {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  background-image:
    radial-gradient(60% 60% at 50% 0%, rgba(124, 92, 255, 0.18) 0%, transparent 70%),
    radial-gradient(40% 40% at 90% 10%, rgba(74, 200, 255, 0.12) 0%, transparent 70%);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

/* ===== Logo ===== */
.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 22px;
}

.logo__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--gradient-accent);
  color: #fff;
  font-size: 18px;
}

.logo__text {
  font-weight: 300;
  letter-spacing: 0.22em;
}

.logo--footer {
  font-size: 20px;
}

/* ===== Buttons ===== */
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
  white-space: nowrap;
}

.button:hover {
  transform: translateY(-2px);
}

.button--accent {
  background: var(--gradient-accent);
  color: #fff;
  box-shadow: var(--shadow-glow);
}

.button--accent:hover {
  box-shadow: 0 24px 70px -18px rgba(124, 92, 255, 0.6);
}

.button--ghost {
  background: var(--color-surface-2);
  color: var(--color-text);
  border-color: var(--color-border);
}

.button--ghost:hover {
  border-color: var(--color-accent);
}

.button--outline {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.button--outline:hover {
  border-color: var(--color-accent);
  background: var(--color-surface-2);
}

.button--lg {
  padding: 15px 32px;
  font-size: 16px;
}

/* ===== Header ===== */
.header {
  position: relative;
  background: transparent;
  border-bottom: none;
  z-index: 10;
}

.header__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 16px 24px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 16px;
}

.header__logo {
  justify-self: start;
}

.header__nav {
  justify-self: center;
}

.header__cta {
  justify-self: end;
}

/* ===== Burger (mobile only) ===== */
.nav-burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  justify-self: end;
  cursor: pointer;
}

.nav-burger span {
  display: block;
  width: 24px;
  height: 2px;
  border-radius: 2px;
  background: var(--color-text);
  transition: transform 0.25s ease, opacity 0.2s ease;
}

.nav-toggle:checked ~ .nav-burger span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle:checked ~ .nav-burger span:nth-child(2) {
  opacity: 0;
}

.nav-toggle:checked ~ .nav-burger span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ===== Nav ===== */
.nav__list {
  display: flex;
  gap: 8px;
}

.nav__link {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 999px;
  color: var(--color-text-muted);
  font-weight: 500;
  transition: color 0.2s ease, background 0.2s ease;
}

.nav__link:hover {
  color: var(--color-text);
  background: var(--color-surface-2);
}

/* ===== Hero ===== */
.hero {
  padding: 96px 24px 80px;
}

.hero__inner {
  max-width: 820px;
  margin: 0 auto;
  text-align: center;
}

.hero__badge {
  display: inline-block;
  padding: 7px 16px;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 28px;
}

.hero__title {
  margin: 0 0 20px;
  font-size: clamp(38px, 6vw, 64px);
  line-height: 1.08;
  font-weight: 800;
  letter-spacing: -0.03em;
}

.hero__accent {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__subtitle {
  margin: 0 auto 36px;
  max-width: 560px;
  font-size: 19px;
  color: var(--color-text-muted);
}

.hero__actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ===== Metrics ===== */
.metrics {
  padding: 12px 24px 40px;
}

.metrics__inner {
  max-width: var(--container);
  margin: 0 auto;
}

.metrics__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.metric-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 28px 20px;
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.metric-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-accent);
}

.metric-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 14px;
  background: rgba(74, 200, 255, 0.14);
  color: var(--color-accent-2);
  margin-bottom: 16px;
}

.metric-card__icon svg {
  width: 26px;
  height: 26px;
}

.metric-card__value {
  font-size: 32px;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.metric-card__label {
  margin-top: 4px;
  font-size: 14px;
  color: var(--color-text-muted);
}

/* ===== Section head ===== */
.section-head {
  text-align: center;
  max-width: 620px;
  margin: 0 auto 56px;
}

.section-head__title {
  margin: 0 0 14px;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.section-head__subtitle {
  margin: 0;
  font-size: 17px;
  color: var(--color-text-muted);
}

/* ===== Features ===== */
.features {
  padding: 80px 24px;
}

.features__inner {
  max-width: var(--container);
  margin: 0 auto;
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.feature-card {
  padding: 30px;
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-accent);
  background: var(--color-surface-2);
}

.feature-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: rgba(124, 92, 255, 0.14);
  font-size: 24px;
  margin-bottom: 18px;
}

.feature-card__title {
  margin: 0 0 10px;
  font-size: 19px;
  font-weight: 700;
}

.feature-card__text {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 15px;
}

/* ===== Download ===== */
.download {
  padding: 80px 24px;
}

.download__inner {
  max-width: var(--container);
  margin: 0 auto;
}

.download__grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 18px;
}

.platform-card {
  padding: 28px 20px;
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  text-align: center;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.platform-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-accent);
}

.platform-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  margin: 0 auto;
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(124, 92, 255, 0.18), rgba(74, 200, 255, 0.18));
  color: var(--color-text);
  transition: background 0.2s ease, color 0.2s ease;
}

.platform-card__icon svg {
  width: 30px;
  height: 30px;
}

.platform-card:hover .platform-card__icon {
  background: var(--gradient-accent);
  color: #fff;
}

.platform-card__title {
  margin: 14px 0 4px;
  font-size: 18px;
  font-weight: 700;
}

.platform-card__meta {
  margin: 0 0 18px;
  font-size: 13px;
  color: var(--color-text-muted);
}

.platform-card__btn {
  width: 100%;
}

/* ===== FAQ ===== */
.faq {
  padding: 80px 24px;
}

.faq__inner {
  max-width: 800px;
  margin: 0 auto;
}

.faq__list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq__item {
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: 4px 24px;
  transition: border-color 0.2s ease;
}

.faq__item[open] {
  border-color: var(--color-accent);
}

.faq__question {
  list-style: none;
  cursor: pointer;
  padding: 18px 0;
  font-weight: 600;
  font-size: 17px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq__question::-webkit-details-marker {
  display: none;
}

.faq__question::after {
  content: "+";
  font-size: 22px;
  color: var(--color-accent);
  transition: transform 0.2s ease;
}

.faq__item[open] .faq__question::after {
  content: "−";
}

.faq__answer {
  margin: 0;
  padding: 0 0 20px;
  color: var(--color-text-muted);
  font-size: 15px;
}

/* Плавное раскрытие/закрытие на чистом CSS */
.faq__item::details-content {
  height: 0;
  overflow: hidden;
  transition: height 0.3s ease, content-visibility 0.3s ease allow-discrete;
}

.faq__item[open]::details-content {
  height: auto;
}

/* ===== CTA ===== */
.cta {
  padding: 40px 24px 100px;
}

.cta__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 64px 32px;
  text-align: center;
  border-radius: var(--radius-lg);
  background:
    radial-gradient(80% 120% at 50% 0%, rgba(124, 92, 255, 0.35) 0%, transparent 70%),
    var(--color-surface);
  border: 1px solid var(--color-border);
}

.cta__title {
  margin: 0 0 14px;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.cta__text {
  margin: 0 auto 32px;
  max-width: 480px;
  font-size: 17px;
  color: var(--color-text-muted);
}

/* ===== Footer ===== */
.footer {
  border-top: 1px solid var(--color-border);
  background: #090b13;
}

.footer__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 56px 24px 36px;
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 32px;
}

.footer__tagline {
  margin: 16px 0 0;
  max-width: 280px;
  color: var(--color-text-muted);
  font-size: 15px;
}

.footer__heading {
  margin: 0 0 16px;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer__link {
  color: var(--color-text);
  font-size: 15px;
  transition: color 0.2s ease;
}

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

.footer__bottom {
  max-width: var(--container);
  margin: 0 auto;
  padding: 22px 24px;
  border-top: 1px solid var(--color-border);
}

.footer__copy {
  margin: 0;
  font-size: 14px;
  color: var(--color-text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .features__grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .download__grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .metrics__grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer__inner {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 760px) {
  .header__inner {
    grid-template-columns: 1fr auto;
    align-items: center;
  }
  .nav-burger {
    display: flex;
  }
  .header__cta {
    display: none;
  }
  .header__nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    width: 100%;
    height: 0;
    overflow: hidden;
    background: var(--color-surface);
    transition: height 0.3s ease;
  }
  .nav-toggle:checked ~ .header__nav {
    height: auto;
  }
  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 12px 24px;
  }
  .nav__link {
    display: block;
    text-align: left;
  }
}

@media (max-width: 560px) {
  .features__grid,
  .download__grid {
    grid-template-columns: 1fr;
  }
  .footer__inner {
    grid-template-columns: 1fr;
  }
  .metrics__grid {
    grid-template-columns: 1fr;
  }
}