:root {
  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 16px;
  --bg: #f7f8fb;
  --surface: #ffffff;
  --foreground: #0f172a;
  --muted: #64748b;
  --border: #e5e7eb;
  --border-soft: #eef1f5;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --success: #16a34a;
  --success-bg: #f0fdf4;
  --success-border: #bbf7d0;
  --danger: #dc2626;
  --danger-bg: #fef2f2;
  --danger-border: #fecaca;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(1200px 500px at 5% -10%, rgba(37, 99, 235, 0.08), transparent 60%),
    radial-gradient(900px 500px at 100% 0%, rgba(139, 92, 246, 0.06), transparent 55%),
    var(--bg);
  color: var(--foreground);
  font-family: Inter, ui-sans-serif, system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
  font-feature-settings: "cv02", "cv03", "cv04", "cv11";
  line-height: 1.6;
}

button,
input,
textarea,
select {
  font-family: inherit;
}

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

a:hover {
  text-decoration: underline;
}

.page {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 28px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius);
  background: linear-gradient(140deg, #2563eb, #6366f1);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 10px 22px -10px rgba(37, 99, 235, 0.45);
}

.brand-title {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.brand-sub {
  margin: 2px 0 0;
  font-size: 13px;
  color: var(--muted);
}

.nav-link {
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface);
  transition: color 150ms, border-color 150ms, background-color 150ms;
}

.nav-link:hover {
  color: var(--primary);
  border-color: #bfdbfe;
  background: #eff6ff;
  text-decoration: none;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
}

.card h1 {
  margin: 0 0 8px;
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.2;
}

.lead {
  margin: 0 0 28px;
  font-size: 15px;
  color: var(--muted);
}

.prose h2 {
  margin: 28px 0 10px;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.prose p,
.prose li {
  margin: 0 0 12px;
  font-size: 14px;
  color: #334155;
}

.prose ul {
  margin: 0 0 16px;
  padding-left: 22px;
}

.prose li {
  margin-bottom: 8px;
}

.updated {
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--border-soft);
  font-size: 12px;
  color: var(--muted);
}

/* Contact form */
.form-grid {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.field label {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--foreground);
}

.field input,
.field textarea {
  width: 100%;
  padding: 11px 14px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #fff;
  color: var(--foreground);
  font-size: 14px;
  outline: none;
  transition: border-color 150ms, box-shadow 150ms;
}

.field input:focus,
.field textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}

.field textarea {
  min-height: 140px;
  resize: vertical;
}

.field-hint {
  margin-top: 6px;
  font-size: 12px;
  color: var(--muted);
}

.btn-submit {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-width: 140px;
  height: 42px;
  padding: 0 20px;
  border: none;
  border-radius: var(--radius);
  background: var(--primary);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 150ms, transform 150ms, box-shadow 150ms;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.25);
}

.btn-submit:hover:not(:disabled) {
  background: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.32);
}

.btn-submit:disabled {
  opacity: 0.65;
  cursor: not-allowed;
}

.form-error {
  padding: 10px 12px;
  border-radius: var(--radius);
  border: 1px solid var(--danger-border);
  background: var(--danger-bg);
  color: var(--danger);
  font-size: 13px;
  line-height: 1.45;
}

.form-error[hidden],
.thank-you[hidden] {
  display: none;
}

.thank-you {
  text-align: center;
  padding: 24px 12px 8px;
}

.thank-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 18px;
  border-radius: 50%;
  background: var(--success-bg);
  border: 1px solid var(--success-border);
  color: var(--success);
  display: flex;
  align-items: center;
  justify-content: center;
}

.thank-you h2 {
  margin: 0 0 10px;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.thank-you p {
  margin: 0 auto 20px;
  max-width: 420px;
  font-size: 14px;
  color: var(--muted);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 38px;
  padding: 0 16px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #fff;
  color: var(--foreground);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 150ms, border-color 150ms;
}

.btn-secondary:hover {
  background: var(--bg);
  border-color: #cbd5e1;
}

@media (max-width: 640px) {
  .page {
    padding: 24px 16px 48px;
  }

  .card {
    padding: 22px 18px;
  }

  .topbar {
    flex-direction: column;
    align-items: flex-start;
  }
}