.skip-link {
  position: fixed;
  top: var(--space-4);
  left: var(--space-4);
  z-index: 1000;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-pill);
  background: var(--color-surface-dark);
  color: var(--color-text-on-dark);
  font-weight: 700;
  transform: translateY(-180%);
  transition: transform var(--transition-fast);
}

.skip-link:focus {
  transform: translateY(0);
}

/* Header */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid transparent;
  background: rgba(248, 247, 242, 0.88);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  transition:
    background var(--transition-standard),
    border-color var(--transition-standard),
    box-shadow var(--transition-standard);
}

.site-header.is-scrolled {
  border-color: var(--color-border);
  background: rgba(248, 247, 242, 0.96);
  box-shadow: 0 12px 40px rgba(16, 19, 17, 0.06);
}

.site-header__inner {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  min-height: 78px;
  gap: var(--space-6);
}

/* Brand */

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  width: max-content;
}

.brand__symbol {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 14px;
  background: var(--color-brand-aqua);
  color: var(--color-text-primary);
  font-size: 1.35rem;
  font-weight: 900;
  letter-spacing: -0.08em;
}

.brand__name {
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: -0.03em;
}

/* Navigation */

.primary-navigation {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(1rem, 2.5vw, 2rem);
}

.primary-navigation a {
  position: relative;
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 650;
  transition: color var(--transition-fast);
}

.primary-navigation a::after {
  position: absolute;
  right: 0;
  bottom: -0.45rem;
  left: 0;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--color-brand-aqua);
  content: "";
  opacity: 0;
  transform: scaleX(0.5);
  transition:
    opacity var(--transition-fast),
    transform var(--transition-fast);
}

.primary-navigation a:hover,
.primary-navigation a:focus-visible {
  color: var(--color-text-primary);
}

.primary-navigation a:hover::after,
.primary-navigation a:focus-visible::after {
  opacity: 1;
  transform: scaleX(1);
}

.navigation-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--color-border);
  border-radius: 14px;
  background: var(--color-surface);
  cursor: pointer;
}

.navigation-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  border-radius: var(--radius-pill);
  background: var(--color-text-primary);
  transition:
    transform var(--transition-fast),
    opacity var(--transition-fast);
}

/* Buttons */

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 1.35rem;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-size: var(--font-size-sm);
  font-weight: 750;
  line-height: 1;
  cursor: pointer;
  transition:
    transform var(--transition-fast),
    background var(--transition-fast),
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

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

.button:active {
  transform: translateY(0);
}

.button--primary {
  background: var(--color-brand-aqua);
  color: var(--color-text-primary);
  box-shadow: 0 12px 30px rgba(0, 209, 178, 0.22);
}

.button--primary:hover {
  box-shadow: 0 16px 36px rgba(0, 209, 178, 0.3);
}

.button--secondary {
  border-color: var(--color-border-strong);
  background: rgba(255, 255, 255, 0.55);
  color: var(--color-text-primary);
}

.button--secondary:hover {
  border-color: var(--color-text-primary);
  background: var(--color-surface);
}

/* Feature cards */

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-5);
}

.feature-card {
  position: relative;
  min-height: 260px;
  padding: var(--space-6);
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.72);
  box-shadow: var(--shadow-soft);
  transition:
    transform var(--transition-standard),
    border-color var(--transition-standard),
    box-shadow var(--transition-standard);
}

.feature-card::before {
  position: absolute;
  top: 0;
  right: 0;
  width: 150px;
  height: 150px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    rgba(0, 209, 178, 0.16),
    transparent 68%
  );
  content: "";
  transform: translate(28%, -32%);
}

.feature-card:hover {
  border-color: rgba(0, 209, 178, 0.38);
  box-shadow: var(--shadow-floating);
  transform: translateY(-6px);
}

.feature-card__number {
  display: inline-flex;
  margin-bottom: var(--space-7);
  color: var(--color-brand-aqua-deep);
  font-size: var(--font-size-sm);
  font-weight: 800;
}

.feature-card h3 {
  margin-bottom: var(--space-3);
  font-size: var(--font-size-lg);
}

.feature-card p {
  margin-bottom: 0;
  color: var(--color-text-secondary);
}

/* Media areas */

.media-stage {
  min-height: 420px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(
      135deg,
      rgba(255, 255, 255, 0.86),
      rgba(223, 251, 245, 0.55)
    );
  box-shadow: var(--shadow-soft);
}

.media-stage--video {
  background:
    linear-gradient(
      145deg,
      rgba(17, 21, 19, 0.98),
      rgba(17, 21, 19, 0.9)
    );
}

/* FAQ */

.faq-list {
  display: grid;
  gap: var(--space-3);
}

.faq-item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.72);
  transition:
    border-color var(--transition-fast),
    background var(--transition-fast);
}

.faq-item[open] {
  border-color: rgba(0, 209, 178, 0.45);
  background: var(--color-surface);
}

.faq-item summary {
  position: relative;
  padding: var(--space-5) 3.5rem var(--space-5) var(--space-5);
  font-weight: 750;
  cursor: pointer;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  position: absolute;
  top: 50%;
  right: var(--space-5);
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-brand-aqua-soft);
  color: var(--color-text-primary);
  content: "+";
  display: grid;
  place-items: center;
  font-size: 1.2rem;
  font-weight: 800;
  transform: translateY(-50%);
  transition: transform var(--transition-fast);
}

.faq-item[open] summary::after {
  transform: translateY(-50%) rotate(45deg);
}

.faq-item p {
  max-width: 760px;
  padding: 0 var(--space-5) var(--space-5);
  margin-bottom: 0;
  color: var(--color-text-secondary);
}

.faq-item p a {
  color: var(--color-brand-aqua-deep);
  font-weight: 700;
}

/* Contact */

.contact-panel,
.download-panel {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1.1fr);
  align-items: center;
  gap: var(--space-8);
  padding: clamp(2rem, 5vw, 4rem);
  border-radius: var(--radius-lg);
}

.contact-panel {
  background: var(--color-surface-dark);
  color: var(--color-text-on-dark);
  box-shadow: var(--shadow-floating);
}

.contact-panel .section-label {
  color: var(--color-brand-aqua);
}

.contact-panel__title,
.download-panel__title {
  margin-bottom: var(--space-4);
  font-size: clamp(2rem, 4vw, 3.5rem);
}

.contact-panel__description {
  max-width: 520px;
  margin-bottom: 0;
  color: rgba(248, 250, 249, 0.7);
}

.contact-links {
  display: grid;
  gap: var(--space-3);
}

.contact-links a {
  display: grid;
  gap: var(--space-2);
  padding: var(--space-5);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.06);
  transition:
    border-color var(--transition-fast),
    background var(--transition-fast),
    transform var(--transition-fast);
}

.contact-links a:hover {
  border-color: rgba(0, 209, 178, 0.58);
  background: rgba(0, 209, 178, 0.08);
  transform: translateY(-3px);
}

.contact-links span {
  color: rgba(248, 250, 249, 0.66);
  font-size: var(--font-size-sm);
}

.contact-links strong {
  overflow-wrap: anywhere;
  font-size: var(--font-size-md);
}

/* Download */

.download-panel {
  border: 1px solid rgba(0, 209, 178, 0.24);
  background:
    radial-gradient(
      circle at top right,
      rgba(0, 209, 178, 0.18),
      transparent 38%
    ),
    var(--color-surface);
  box-shadow: var(--shadow-soft);
}

.download-panel p {
  max-width: 560px;
  margin-bottom: 0;
  color: var(--color-text-secondary);
}

.store-buttons {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-4);
}

.store-button {
  display: flex;
  min-height: 88px;
  flex-direction: column;
  justify-content: center;
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-md);
  background: var(--color-surface-dark);
  color: var(--color-text-on-dark);
  font-size: var(--font-size-md);
  font-weight: 750;
}

.store-button small {
  margin-top: var(--space-1);
  color: rgba(248, 250, 249, 0.6);
  font-size: var(--font-size-xs);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* Footer */

.site-footer {
  padding-top: var(--space-8);
  background: var(--color-surface-dark);
  color: var(--color-text-on-dark);
}

.site-footer__top {
  display: grid;
  grid-template-columns: 0.8fr 2fr;
  gap: var(--space-8);
  padding-bottom: var(--space-8);
}

.brand--footer .brand__symbol {
  box-shadow: 0 12px 28px rgba(0, 209, 178, 0.2);
}

.site-footer__navigation {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-6);
}

.site-footer__navigation > div {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--space-3);
}

.site-footer__navigation h2 {
  margin-bottom: var(--space-2);
  color: rgba(248, 250, 249, 0.48);
  font-size: var(--font-size-xs);
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.site-footer__navigation a {
  color: rgba(248, 250, 249, 0.78);
  font-size: var(--font-size-sm);
  transition: color var(--transition-fast);
}

.site-footer__navigation a:hover {
  color: var(--color-brand-aqua);
}

.site-footer__bottom {
  display: flex;
  min-height: 82px;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.site-footer__bottom p {
  margin-bottom: 0;
  color: rgba(248, 250, 249, 0.54);
  font-size: var(--font-size-sm);
}

.social-links {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* Focus states */

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid rgba(0, 209, 178, 0.42);
  outline-offset: 4px;
}