:root {
  --primary-navy: #0D223A;
  --ocean-navy: #042948;
  --teal-accent: #0EA5E9;
  --teal-light: #E0F2FE;
  --teal-dark: #0369A1;
  --bg-page: #F8FAFC;
  --bg-card: #FFFFFF;
  --border-color: #E2E8F0;
  --text-main: #0F172A;
  --text-muted: #64748B;
  --text-sub: #475569;
  --danger-bg: #FEF2F2;
  --danger-border: #FCA5A5;
  --danger-text: #991B1B;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --radius-card: 16px;
  --radius-btn: 10px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Header & Brand Banner */
.site-header {
  background: linear-gradient(135deg, var(--ocean-navy) 0%, var(--primary-navy) 100%);
  color: #FFFFFF;
  padding: 28px 20px;
  border-bottom: 2px solid var(--teal-accent);
}

.header-container {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
  color: #FFFFFF;
}

.brand-logo {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
}

.brand-title {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.3px;
}

.brand-tagline {
  font-size: 13px;
  color: #93C5FD;
  font-weight: 400;
}

.nav-links {
  display: flex;
  gap: 16px;
  align-items: center;
}

.nav-links a {
  color: #E2E8F0;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  background: rgba(255, 255, 255, 0.12);
  color: #FFFFFF;
}

/* Main Content Area */
.main-content {
  max-width: 860px;
  margin: 40px auto;
  padding: 0 20px 60px;
}

.doc-card {
  background: var(--bg-card);
  border-radius: var(--radius-card);
  border: 1px solid var(--border-color);
  padding: 40px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.03);
}

@media (max-width: 640px) {
  .doc-card {
    padding: 24px 18px;
  }
}

.doc-header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.doc-badge {
  display: inline-block;
  background: var(--teal-light);
  color: var(--teal-dark);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: 20px;
  margin-bottom: 12px;
}

.doc-title {
  font-size: 32px;
  font-weight: 800;
  color: var(--primary-navy);
  letter-spacing: -0.5px;
  margin-bottom: 8px;
}

.doc-meta {
  font-size: 13px;
  color: var(--text-muted);
}

/* Typography & Sections */
.doc-body h2 {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary-navy);
  margin-top: 36px;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.doc-body h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-main);
  margin-top: 20px;
  margin-bottom: 8px;
}

.doc-body p {
  color: var(--text-sub);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 16px;
}

.doc-body ul,
.doc-body ol {
  color: var(--text-sub);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 18px;
  padding-left: 24px;
}

.doc-body li {
  margin-bottom: 8px;
}

/* Callout Boxes */
.callout {
  padding: 16px 20px;
  border-radius: 12px;
  margin: 24px 0;
  font-size: 14px;
  line-height: 1.6;
}

.callout-info {
  background: var(--teal-light);
  border-left: 4px solid var(--teal-accent);
  color: var(--teal-dark);
}

.callout-warning {
  background: var(--danger-bg);
  border-left: 4px solid var(--danger-border);
  color: var(--danger-text);
}

.callout-warning h4 {
  font-weight: 700;
  margin-bottom: 6px;
}

/* Subscription Buttons */
.store-btn-group {
  display: flex;
  gap: 12px;
  margin: 16px 0;
  flex-wrap: wrap;
}

.btn-store {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: #FFFFFF;
  color: var(--text-main);
  border: 1px solid var(--border-color);
  padding: 10px 18px;
  border-radius: var(--radius-btn);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
  transition: all 0.2s ease;
}

.btn-store:hover {
  background: #F1F5F9;
  border-color: #CBD5E1;
}

/* Forms */
.form-card {
  background: #F8FAFC;
  border: 1px solid var(--border-color);
  border-radius: 14px;
  padding: 24px;
  margin-top: 28px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 14px;
  font-family: inherit;
  background: #FFFFFF;
}

.form-control:focus {
  outline: none;
  border-color: var(--teal-accent);
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.15);
}

.checkbox-label {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 13px;
  color: var(--text-sub);
  line-height: 1.5;
  cursor: pointer;
}

.checkbox-label input {
  margin-top: 3px;
}

.btn-submit-danger {
  background: #DC2626;
  color: #FFFFFF;
  border: none;
  padding: 12px 24px;
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--radius-btn);
  cursor: pointer;
  transition: background 0.2s ease;
}

.btn-submit-danger:hover {
  background: #B91C1C;
}

.btn-submit-danger:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Status Alert */
.form-status {
  margin-top: 16px;
  padding: 14px 18px;
  border-radius: 8px;
  font-size: 14px;
  display: none;
}

.form-status.success {
  display: block;
  background: #DEF7EC;
  color: #03543F;
  border: 1px solid #84E1BC;
}

.form-status.error {
  display: block;
  background: #FDE8E8;
  color: #9B1C1C;
  border: 1px solid #F8B4B4;
}

/* Footer */
.site-footer {
  text-align: center;
  padding: 30px 20px;
  font-size: 13px;
  color: var(--text-muted);
  border-top: 1px solid var(--border-color);
  background: #FFFFFF;
}

.footer-links {
  margin-bottom: 12px;
  display: flex;
  justify-content: center;
  gap: 20px;
}

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

.footer-links a:hover {
  color: var(--primary-navy);
  text-decoration: underline;
}