.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(16px);
  background: rgba(5, 8, 20, 0.74);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: var(--header-height);
  position: relative;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 850;
  letter-spacing: -0.02em;
  color: #fff;
  white-space: nowrap;
}

.logo-mark {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #041018;
  font-weight: 950;
  box-shadow: 0 10px 28px rgba(34, 211, 238, 0.22);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.main-nav a {
  text-decoration: none;
  color: var(--muted);
  font-weight: 650;
  transition:
    color 0.2s ease,
    transform 0.2s ease;
}

.main-nav a:hover {
  color: #fff;
}

.nav-cta {
  padding: 10px 16px;
  border-radius: 999px;
  border: 1px solid rgba(34, 211, 238, 0.25);
  background: rgba(34, 211, 238, 0.1);
  color: var(--accent) !important;
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.05);
  color: #fff;
  font-size: 22px;
  cursor: pointer;
}

.hero {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 28px;
  align-items: start;
  padding: 76px 0 54px;
}

.hero-copy h1 span {
  display: block;
}

.hero-copy h1 .accent-text {
  margin-top: 8px;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.04);
  color: #cbd5e1;
  font-size: 13px;
  font-weight: 650;
}

.accent-text {
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.lead {
  font-size: 18px;
  color: var(--muted);
  max-width: 760px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: 28px 0;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 30px;
}

.metric {
  padding: 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
}

.metric strong {
  display: block;
  font-size: 24px;
  color: #fff;
  letter-spacing: -0.03em;
}

.metric span {
  color: var(--muted);
  font-size: 13px;
}

.hero-card {
  padding: 24px;
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.92), rgba(8, 13, 25, 0.88));
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.hero-card h2 {
  margin-bottom: 10px;
  font-size: 24px;
}

.hero-card p {
  color: var(--muted);
}

.feature-list {
  list-style: none;
  padding: 0;
  margin: 20px 0;
  display: grid;
  gap: 12px;
}

.feature-list li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  color: #dbe3ef;
}

.check {
  width: 22px;
  height: 22px;
  border-radius: 999px;
  display: grid;
  place-items: center;
  background: rgba(52, 211, 153, 0.15);
  color: var(--accent-2);
  font-weight: 950;
  flex: 0 0 auto;
  margin-top: 2px;
}

.hero-card .btn {
  width: 100%;
}

section {
  padding: 74px 0;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.card {
  padding: 24px;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.035);
  border: 1px solid var(--border);
  transition:
    transform 0.22s ease,
    border-color 0.22s ease,
    background 0.22s ease,
    box-shadow 0.22s ease;
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(34, 211, 238, 0.28);
  background: rgba(255, 255, 255, 0.055);
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.2);
}

.icon {
  width: 48px;
  height: 48px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  font-size: 24px;
  background: linear-gradient(
    135deg,
    rgba(34, 211, 238, 0.18),
    rgba(52, 211, 153, 0.16)
  );
  margin-bottom: 14px;
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.card p {
  color: var(--muted);
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.step {
  padding: 22px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.035);
  border: 1px solid var(--border);
}

.step-num {
  display: inline-flex;
  margin-bottom: 10px;
  color: var(--accent);
  font-weight: 950;
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.step h3 {
  font-size: 19px;
}

.step p {
  color: var(--muted);
  font-size: 15px;
}

.logos {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 12px;
}

.logo-placeholder {
  min-height: 92px;
  display: grid;
  place-items: center;
  padding: 18px;
  border-radius: 18px;
  border: 1px dashed rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.025);
  color: #94a3b8;
  font-weight: 700;
  text-align: center;
}

.contact-wrap {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 22px;
  align-items: start;
}

.contact-panel,
.form-card {
  padding: 26px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.035);
  box-shadow: var(--shadow);
}

.form-card {
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.94), rgba(7, 11, 20, 0.94));
}

.contact-panel h2,
.form-card h2 {
  margin-bottom: 10px;
  font-size: 28px;
  letter-spacing: -0.03em;
}

.contact-panel p,
.form-card > p {
  color: var(--muted);
}

.contact-list {
  display: grid;
  gap: 14px;
  margin: 22px 0;
}

.contact-item {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.contact-item .icon {
  width: 42px;
  height: 42px;
  font-size: 20px;
  margin: 0;
  border-radius: 13px;
}

.contact-item strong {
  display: block;
  color: #fff;
  margin-bottom: 2px;
}

.contact-item a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 750;
  word-break: break-word;
}

.contact-item a:hover {
  text-decoration: underline;
}

.socials {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.socials a {
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.04);
  text-decoration: none;
  font-weight: 750;
  color: #e2e8f0;
  transition:
    transform 0.2s ease,
    border-color 0.2s ease,
    background 0.2s ease;
}

.socials a:hover {
  transform: translateY(-2px);
  border-color: rgba(34, 211, 238, 0.3);
  background: rgba(34, 211, 238, 0.08);
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-top: 20px;
}

.field {
  display: grid;
  gap: 7px;
}

.field.full {
  grid-column: 1 / -1;
}

label {
  font-size: 14px;
  color: #cbd5e1;
  font-weight: 700;
}

.consent {
  grid-column: 1 / -1;
  display: flex;
  gap: 10px;
  align-items: flex-start;
  color: var(--muted);
  font-size: 14px;
}

.consent input {
  width: auto;
  margin-top: 4px;
  accent-color: var(--accent);
}

.consent a {
  color: var(--accent);
}

.form-grid button[type="submit"] {
  grid-column: 1 / -1;
  width: 100%;
  margin-top: 4px;
  border: 0;
  font-size: 16px;
}

.form-status {
  display: none;
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: 14px;
  font-weight: 650;
}

.form-status.success {
  display: block;
  background: rgba(52, 211, 153, 0.12);
  border: 1px solid rgba(52, 211, 153, 0.25);
  color: #bbf7d0;
}

.form-status.error {
  display: block;
  background: rgba(248, 113, 113, 0.12);
  border: 1px solid rgba(248, 113, 113, 0.25);
  color: #fecaca;
}

#thanks {
  display: none;
}

#thanks:target {
  display: block;
}

.thanks-box {
  padding: 24px;
  border-radius: var(--radius);
  background: rgba(52, 211, 153, 0.1);
  border: 1px solid rgba(52, 211, 153, 0.24);
  color: #bbf7d0;
  text-align: center;
  font-weight: 750;
}

.legal {
  padding-top: 28px;
  padding-bottom: 28px;
}

.legal-box {
  padding: 22px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}

.legal-box h2 {
  font-size: 24px;
  margin-bottom: 10px;
}

.legal-box a {
  color: var(--accent);
}

.footer {
  padding: 28px 0 42px;
  border-top: 1px solid var(--border);
  color: var(--muted);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  align-items: center;
}

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

.footer a:hover {
  text-decoration: underline;
}
/* --- Button Back to Top --- */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  z-index: 999;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #041018;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: 900;
  text-decoration: none;
  box-shadow: 0 10px 30px rgba(34, 211, 238, 0.3);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: 
    opacity 0.3s ease,
    visibility 0.3s ease,
    transform 0.3s ease,
    box-shadow 0.2s ease;
  cursor: pointer;
  border: none;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 15px 40px rgba(34, 211, 238, 0.4);
}

.back-to-top svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
}

@media (max-width: 640px) {
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    font-size: 20px;
  }
  
  .back-to-top svg {
    width: 20px;
    height: 20px;
  }
}

/* --- Form Validation Styles --- */
.error-message {
  display: block;
  font-size: 12px;
  color: var(--danger);
  margin-top: 4px;
  min-height: 16px; /* Чтобы layout не прыгал */
  opacity: 0;
  transition: opacity 0.2s ease;
}

.field.has-error input,
.field.has-error textarea {
  border-color: var(--danger);
  background: rgba(248, 113, 113, 0.05);
}

.field.has-error .error-message {
  opacity: 1;
}

/* Убираем нативные браузерные сообщения об ошибках, так как делаем свои */
input:invalid,
textarea:invalid {
  box-shadow: none;
}