/* ============================================================
   PromptMail — Design System & Styles
   ============================================================ */

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --blue: #3B82F6;
  --blue-hover: #2563EB;
  --purple: #8B5CF6;
  --bg: #09090B;
  --bg-subtle: #111113;
  --bg-card: #18181B;
  --bg-code: #1E1E22;
  --border: #27272A;
  --border-light: #3F3F46;
  --text: #FAFAFA;
  --text-secondary: #A1A1AA;
  --text-muted: #71717A;
  --radius: 12px;
  --radius-sm: 8px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', monospace;
  --max-w: 1200px;
  --transition: 150ms ease;
}

[data-theme="light"] {
  --bg: #FAFAFA;
  --bg-subtle: #F4F4F5;
  --bg-card: #FFFFFF;
  --bg-code: #F4F4F5;
  --border: #E4E4E7;
  --border-light: #D4D4D8;
  --text: #09090B;
  --text-secondary: #52525B;
  --text-muted: #A1A1AA;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; }
code, pre { font-family: var(--mono); }

/* --- Utilities --- */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; }
.text-gradient {
  background: linear-gradient(135deg, var(--blue), var(--purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.mono { font-family: var(--mono); font-size: 0.875em; }
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  background: var(--bg-subtle);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-weight: 500;
  transition: all var(--transition);
  white-space: nowrap;
}
.btn-primary {
  background: var(--blue);
  color: #fff;
}
.btn-primary:hover { background: var(--blue-hover); transform: translateY(-1px); }
.btn-secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-secondary:hover { border-color: var(--border-light); background: var(--bg-subtle); }

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 16px 0;
  border-bottom: 1px solid transparent;
  transition: all var(--transition);
  background: transparent;
}
.nav.scrolled {
  background: rgba(9, 9, 11, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-color: var(--border);
}
[data-theme="light"] .nav.scrolled {
  background: rgba(250, 250, 250, 0.8);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.125rem;
}
.nav-logo svg { width: 28px; height: 28px; }
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: color var(--transition);
}
.nav-links a:hover { color: var(--text); }
.nav-actions { display: flex; align-items: center; gap: 12px; }
.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--text-secondary);
  transition: all var(--transition);
  border: 1px solid transparent;
}
.theme-toggle:hover {
  color: var(--text);
  background: var(--bg-subtle);
  border-color: var(--border);
}
.theme-toggle svg { width: 18px; height: 18px; }
.nav-cta {
  padding: 8px 16px;
  font-size: 0.8125rem;
}

/* Mobile nav */
.nav-mobile-toggle {
  display: none;
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  background: transparent;
  color: var(--text);
}
.nav-mobile-toggle svg { width: 20px; height: 20px; }
.nav-mobile-menu {
  display: none;
  position: fixed;
  top: 60px;
  left: 0;
  right: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  padding: 24px;
  flex-direction: column;
  gap: 16px;
  z-index: 99;
}
.nav-mobile-menu.open { display: flex; }
.nav-mobile-menu a {
  font-size: 1rem;
  color: var(--text-secondary);
  padding: 8px 0;
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-cta { display: none; }
  .nav-mobile-toggle { display: flex; }
}

/* --- Hero --- */
.hero {
  padding: 160px 0 100px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.08) 0%, transparent 70%);
  pointer-events: none;
}
.hero-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
  position: relative;
}
.hero h1 {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin: 20px 0 24px;
}
.hero p {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* --- Demo Visual --- */
.demo-section { padding: 0 0 100px; }
.demo-visual {
  max-width: 960px;
  margin: 0 auto;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  overflow: hidden;
  box-shadow:
    0 0 0 1px var(--border),
    0 4px 24px rgba(0,0,0,0.2),
    0 0 80px rgba(59, 130, 246, 0.05);
}
.demo-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-subtle);
}
.demo-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--border-light);
}
.demo-body {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: 400px;
}
.demo-prompt {
  padding: 32px;
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
}
.demo-prompt-label {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 20px;
}
.demo-messages {
  display: flex;
  flex-direction: column;
  gap: 16px;
  flex: 1;
}
.demo-msg {
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  line-height: 1.6;
}
.demo-msg.user {
  background: var(--blue);
  color: #fff;
  align-self: flex-end;
  max-width: 85%;
  border-bottom-right-radius: 4px;
}
.demo-msg.ai {
  background: var(--bg-code);
  color: var(--text-secondary);
  align-self: flex-start;
  max-width: 85%;
  border-bottom-left-radius: 4px;
}
.demo-prompt-input {
  margin-top: 20px;
  display: flex;
  gap: 8px;
}
.demo-prompt-input input {
  flex: 1;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 0.875rem;
  font-family: var(--font);
  outline: none;
}
.demo-prompt-input input:focus { border-color: var(--blue); }
.demo-prompt-input button {
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  background: var(--blue);
  color: #fff;
  font-size: 0.8125rem;
}
.demo-preview {
  padding: 32px;
  display: flex;
  flex-direction: column;
}
.demo-preview-label {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 20px;
}
.demo-email {
  flex: 1;
  background: #FFFFFF;
  border-radius: var(--radius-sm);
  overflow: hidden;
  color: #1a1a1a;
  font-size: 0.875rem;
}
.demo-email-header {
  background: linear-gradient(135deg, var(--blue), var(--purple));
  padding: 32px 24px;
  text-align: center;
  color: #fff;
}
.demo-email-header h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 4px;
}
.demo-email-header p {
  font-size: 0.8125rem;
  opacity: 0.9;
  color: #fff;
}
.demo-email-body {
  padding: 24px;
}
.demo-email-body p {
  font-size: 0.8125rem;
  color: #4a4a4a;
  line-height: 1.6;
  margin-bottom: 16px;
}
.demo-email-btn {
  display: inline-block;
  padding: 10px 24px;
  background: var(--blue);
  color: #fff;
  border-radius: 6px;
  font-size: 0.8125rem;
  font-weight: 500;
}
.demo-email-footer {
  padding: 16px 24px;
  border-top: 1px solid #eee;
  text-align: center;
  font-size: 0.6875rem;
  color: #999;
}

@media (max-width: 768px) {
  .demo-body { grid-template-columns: 1fr; }
  .demo-prompt { border-right: none; border-bottom: 1px solid var(--border); }
}

/* --- How It Works --- */
.how-it-works {
  padding: 100px 0;
  border-top: 1px solid var(--border);
}
.section-label {
  font-family: var(--mono);
  font-size: 0.8125rem;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}
.section-desc {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  max-width: 560px;
  margin-bottom: 60px;
}
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}
.step {
  padding: 32px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: border-color var(--transition);
}
.step:hover { border-color: var(--border-light); }
.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--blue), var(--purple));
  color: #fff;
  font-family: var(--mono);
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 20px;
}
.step h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 12px;
}
.step p {
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.7;
  margin-bottom: 20px;
}
.step-code {
  background: var(--bg-code);
  border-radius: var(--radius-sm);
  padding: 16px;
  overflow-x: auto;
}
.step-code pre {
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--text-secondary);
}
.step-code .kw { color: var(--purple); }
.step-code .str { color: #34D399; }
.step-code .fn { color: var(--blue); }
.step-code .cm { color: var(--text-muted); }
.step-visual {
  background: var(--bg-code);
  border-radius: var(--radius-sm);
  padding: 16px;
}
.step-visual-prompt {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  background: var(--bg);
  border-radius: 6px;
  border: 1px solid var(--border);
}
.step-visual-prompt .cursor {
  width: 2px;
  height: 16px;
  background: var(--blue);
  animation: blink 1s infinite;
}
.step-visual-prompt span {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }

.step-email-mini {
  background: #fff;
  border-radius: 6px;
  overflow: hidden;
  color: #1a1a1a;
}
.step-email-mini-header {
  background: linear-gradient(135deg, var(--blue), var(--purple));
  padding: 12px;
  text-align: center;
}
.step-email-mini-header span {
  color: #fff;
  font-size: 0.75rem;
  font-weight: 600;
}
.step-email-mini-body {
  padding: 12px;
}
.step-email-mini-body .line {
  height: 6px;
  background: #e5e7eb;
  border-radius: 3px;
  margin-bottom: 6px;
}
.step-email-mini-body .line.short { width: 60%; }
.step-email-mini-body .mini-btn {
  display: inline-block;
  padding: 4px 12px;
  background: var(--blue);
  border-radius: 4px;
  margin-top: 4px;
}
.step-email-mini-body .mini-btn span {
  font-size: 0.625rem;
  color: #fff;
}
.step-check {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-top: 8px;
  font-size: 0.6875rem;
  color: #34D399;
  font-family: var(--mono);
}

@media (max-width: 768px) {
  .steps { grid-template-columns: 1fr; }
}

/* --- Benefits --- */
.benefits {
  padding: 100px 0;
  border-top: 1px solid var(--border);
}
.benefits-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.benefit {
  padding: 28px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: border-color var(--transition);
}
.benefit:hover { border-color: var(--border-light); }
.benefit-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: rgba(59, 130, 246, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  color: var(--blue);
}
.benefit-icon svg { width: 20px; height: 20px; }
.benefit h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}
.benefit p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  line-height: 1.7;
}

@media (max-width: 768px) {
  .benefits-grid { grid-template-columns: 1fr; }
}

/* --- Social Proof --- */
.social-proof {
  padding: 80px 0;
  border-top: 1px solid var(--border);
  text-align: center;
}
.social-proof p {
  font-size: 0.875rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-family: var(--mono);
  margin-bottom: 40px;
}
.logos {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
  opacity: 0.4;
}
.logo-placeholder {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-secondary);
  letter-spacing: -0.02em;
}

/* --- CTA Section --- */
.cta-section {
  padding: 100px 0;
  border-top: 1px solid var(--border);
  text-align: center;
}
.cta-section h2 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}
.cta-section p {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  max-width: 480px;
  margin: 0 auto 32px;
}
.cta-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* --- Footer --- */
.footer {
  padding: 48px 0;
  border-top: 1px solid var(--border);
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 24px;
}
.footer-left {
  display: flex;
  align-items: center;
  gap: 24px;
}
.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.9375rem;
}
.footer-logo svg { width: 20px; height: 20px; }
.footer-links {
  display: flex;
  gap: 24px;
}
.footer-links a {
  font-size: 0.8125rem;
  color: var(--text-muted);
  transition: color var(--transition);
}
.footer-links a:hover { color: var(--text); }
.footer-right {
  display: flex;
  align-items: center;
  gap: 16px;
}
.built-with {
  font-size: 0.75rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}
.built-with svg { width: 14px; height: 14px; }

@media (max-width: 600px) {
  .footer-inner { flex-direction: column; text-align: center; }
  .footer-left { flex-direction: column; }
}

/* --- Pricing Page --- */
.page-hero {
  padding: 160px 0 60px;
  text-align: center;
}
.page-hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}
.page-hero p {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  max-width: 480px;
  margin: 0 auto;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  padding: 0 0 100px;
}
.pricing-card {
  padding: 36px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
  display: flex;
  flex-direction: column;
  transition: border-color var(--transition);
}
.pricing-card:hover { border-color: var(--border-light); }
.pricing-card.featured {
  border-color: var(--blue);
  position: relative;
}
.pricing-card.featured::before {
  content: 'Most Popular';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  padding: 4px 14px;
  border-radius: 999px;
  background: var(--blue);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 500;
}
.pricing-tier {
  font-family: var(--mono);
  font-size: 0.8125rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}
.pricing-price {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 4px;
}
.pricing-price span {
  font-size: 1rem;
  font-weight: 400;
  color: var(--text-muted);
}
.pricing-desc {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 28px;
  line-height: 1.6;
}
.pricing-features {
  list-style: none;
  margin-bottom: 32px;
  flex: 1;
}
.pricing-features li {
  padding: 8px 0;
  font-size: 0.875rem;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 10px;
}
.pricing-features li::before {
  content: '✓';
  color: var(--blue);
  font-weight: 600;
  flex-shrink: 0;
}
.pricing-card .btn { width: 100%; justify-content: center; }

@media (max-width: 768px) {
  .pricing-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; padding-bottom: 60px; }
}

/* --- Docs Placeholder --- */
.docs-placeholder {
  padding: 160px 0 100px;
  text-align: center;
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
}
.docs-placeholder-inner {
  max-width: 480px;
}
.docs-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 24px;
  border-radius: var(--radius);
  background: rgba(59, 130, 246, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--blue);
}
.docs-icon svg { width: 28px; height: 28px; }
.docs-placeholder h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 12px;
}
.docs-placeholder p {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: 32px;
  line-height: 1.7;
}

/* --- Animations --- */
@media (prefers-reduced-motion: no-preference) {
  .fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
  }
  .fade-in.visible {
    opacity: 1;
    transform: translateY(0);
  }
}
@media (prefers-reduced-motion: reduce) {
  .fade-in { opacity: 1; transform: none; }
}