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

:root {
  --blue-600: #2563EB;
  --blue-700: #1D4ED8;
  --blue-50: #EFF6FF;
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;
  --green-500: #22C55E;
  --red-400: #F87171;
  --red-500: #EF4444;
  --white: #FFFFFF;
  --radius: 8px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--gray-800);
  line-height: 1.6;
  background: var(--white);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

h1, h2, h3 { line-height: 1.2; }
h1 { font-size: 2.5rem; font-weight: 800; }
h2 { font-size: 1.75rem; font-weight: 700; }
h3 { font-size: 1.1rem; font-weight: 600; }

a { color: var(--blue-600); text-decoration: none; }
a:hover { text-decoration: underline; }

/* === Buttons === */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border-radius: var(--radius);
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.15s ease;
  text-decoration: none;
}
.btn:hover { text-decoration: none; }
.btn-primary {
  background: var(--blue-600);
  color: var(--white);
}
.btn-primary:hover { background: var(--blue-700); }
.btn-secondary {
  background: var(--gray-100);
  color: var(--gray-700);
  border: 1px solid var(--gray-200);
}
.btn-secondary:hover { background: var(--gray-200); }
.btn-sm { padding: 6px 14px; font-size: 0.85rem; }
.btn-lg { padding: 14px 32px; font-size: 1.05rem; }
.btn-block { width: 100%; }

/* === Header === */
.header {
  border-bottom: 1px solid var(--gray-200);
  background: var(--white);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--gray-900);
}
.logo:hover { text-decoration: none; }
.nav-link {
  color: var(--gray-600);
  font-size: 0.9rem;
  font-weight: 500;
  margin-left: 24px;
}
.nav-link:hover, .nav-link.active { color: var(--blue-600); text-decoration: none; }

/* === Hero === */
.hero {
  padding: 80px 0 60px;
  text-align: center;
  background: linear-gradient(180deg, var(--blue-50) 0%, var(--white) 100%);
}
.hero h1 { margin-bottom: 16px; color: var(--gray-900); }
.hero-sub {
  font-size: 1.15rem;
  color: var(--gray-500);
  max-width: 560px;
  margin: 0 auto 32px;
}

/* === Generator === */
.generator {
  padding: 60px 0 80px;
}
.generator-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}

/* Form */
.form-panel { display: flex; flex-direction: column; gap: 24px; }
.form-section {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 20px;
}
.form-section h3 { margin-bottom: 12px; color: var(--gray-700); }

input[type="text"],
input[type="email"],
input[type="number"],
input[type="date"],
textarea,
select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-family: inherit;
  color: var(--gray-800);
  background: var(--white);
  margin-bottom: 8px;
  transition: border-color 0.15s;
}
input:focus, textarea:focus, select:focus {
  outline: none;
  border-color: var(--blue-600);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}
label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--gray-500);
  margin-bottom: 4px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
}
.form-group { margin-bottom: 0; }
.form-group input, .form-group select { margin-bottom: 0; }

/* Line Items */
.line-items-header {
  display: grid;
  grid-template-columns: 1fr 70px 90px 90px 36px;
  gap: 8px;
  padding: 0 0 8px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--gray-400);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.line-item-row {
  display: grid;
  grid-template-columns: 1fr 70px 90px 90px 36px;
  gap: 8px;
  margin-bottom: 8px;
  align-items: center;
}
.line-item-row input { margin-bottom: 0; }
.li-amount-display {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--gray-700);
  text-align: right;
  padding-right: 4px;
}
.line-item-remove {
  width: 32px;
  height: 32px;
  border: none;
  background: none;
  color: var(--gray-400);
  cursor: pointer;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
}
.line-item-remove:hover { background: var(--gray-100); color: var(--red-500); }

/* Pro feature lockout */
.pro-feature { position: relative; opacity: 0.6; }
.pro-feature input:disabled { cursor: not-allowed; }
.pro-badge {
  display: inline-block;
  background: var(--blue-600);
  color: var(--white);
  font-size: 0.65rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 99px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  vertical-align: middle;
  margin-left: 6px;
}
.pro-hint {
  font-size: 0.8rem;
  color: var(--gray-400);
  margin-top: 4px;
}

/* Preview */
.preview-panel { position: relative; }
.preview-sticky { position: sticky; top: 88px; }
.preview-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}
.preview-toolbar h3 { color: var(--gray-600); }

.invoice-preview {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 40px;
  min-height: 600px;
  font-size: 0.85rem;
}

/* Invoice preview styles */
.inv-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 32px;
  padding-bottom: 20px;
  border-bottom: 2px solid var(--blue-600);
}
.inv-title {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--blue-600);
}
.inv-from { text-align: right; color: var(--gray-600); font-size: 0.8rem; line-height: 1.5; }
.inv-from strong { color: var(--gray-800); font-size: 0.9rem; }

.inv-meta {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 32px;
}
.inv-to { color: var(--gray-600); font-size: 0.8rem; line-height: 1.5; }
.inv-to strong { color: var(--gray-800); font-size: 0.9rem; }
.inv-details { text-align: right; }
.inv-details table { margin-left: auto; }
.inv-details td { padding: 2px 0; font-size: 0.8rem; }
.inv-details td:first-child { color: var(--gray-400); padding-right: 16px; text-transform: uppercase; font-size: 0.7rem; font-weight: 600; }

.inv-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 24px;
}
.inv-table th {
  text-align: left;
  padding: 10px 8px;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--gray-400);
  border-bottom: 1px solid var(--gray-200);
}
.inv-table th:nth-child(2),
.inv-table th:nth-child(3),
.inv-table th:nth-child(4) { text-align: right; }
.inv-table td {
  padding: 10px 8px;
  border-bottom: 1px solid var(--gray-100);
  font-size: 0.85rem;
}
.inv-table td:nth-child(2),
.inv-table td:nth-child(3),
.inv-table td:nth-child(4) { text-align: right; }

.inv-totals {
  display: flex;
  justify-content: flex-end;
  margin-bottom: 32px;
}
.inv-totals table { min-width: 200px; }
.inv-totals td { padding: 4px 0; font-size: 0.85rem; }
.inv-totals td:first-child { color: var(--gray-500); padding-right: 24px; }
.inv-totals td:last-child { text-align: right; font-weight: 600; }
.inv-totals tr.inv-total-row td {
  padding-top: 8px;
  border-top: 2px solid var(--gray-800);
  font-size: 1rem;
  font-weight: 700;
  color: var(--gray-900);
}

.inv-notes {
  padding-top: 16px;
  border-top: 1px solid var(--gray-200);
  font-size: 0.8rem;
  color: var(--gray-500);
  line-height: 1.5;
}
.inv-notes strong { color: var(--gray-700); }

.inv-watermark {
  text-align: center;
  margin-top: 32px;
  padding-top: 16px;
  border-top: 1px solid var(--gray-100);
  font-size: 0.7rem;
  color: var(--gray-300);
}
.inv-watermark a { color: var(--gray-400); }

/* === Features === */
/* === How It Works === */
.how-it-works {
  padding: 80px 0;
  background: var(--gray-50);
}
.how-it-works h2 { text-align: center; margin-bottom: 8px; }
.section-sub { text-align: center; color: var(--gray-500); margin-bottom: 48px; }
.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 48px;
  position: relative;
  counter-reset: step;
}
.step-card {
  text-align: left;
  padding: 0;
  background: none;
  border: none;
  position: relative;
}
.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--blue-600);
  color: var(--white);
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 14px;
  flex-shrink: 0;
}
.step-card h3 { margin-bottom: 6px; font-size: 1rem; }
.step-card p { color: var(--gray-500); font-size: 0.88rem; line-height: 1.5; }

/* === Features === */
.features {
  padding: 80px 0;
}
.features h2 { text-align: center; margin-bottom: 48px; }
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}
.feature-card {
  text-align: center;
  padding: 32px 24px;
  background: var(--white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
}
.feature-icon { font-size: 2rem; margin-bottom: 16px; }
.feature-card h3 { margin-bottom: 8px; }
.feature-card p { color: var(--gray-500); font-size: 0.9rem; }

/* === Use Cases === */
.use-cases {
  padding: 80px 0;
  background: var(--gray-50);
}
.use-cases h2 { text-align: center; margin-bottom: 48px; }
.use-cases-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  max-width: 800px;
  margin: 0 auto;
}
.use-case {
  padding: 24px;
  background: var(--white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
}
.use-case h3 { margin-bottom: 8px; }
.use-case p { color: var(--gray-500); font-size: 0.9rem; }

/* === CTA === */
.cta {
  padding: 80px 0;
  text-align: center;
}
.cta h2 { margin-bottom: 8px; }
.cta p { color: var(--gray-500); margin-bottom: 24px; }

/* === Footer === */
.footer {
  border-top: 1px solid var(--gray-200);
  padding: 24px 0;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--gray-400);
}
.footer nav a { color: var(--gray-400); margin-left: 20px; }
.footer nav a:hover { color: var(--gray-600); }

/* === Pricing Page === */
.pricing-hero {
  padding: 60px 0 40px;
  text-align: center;
  background: linear-gradient(180deg, var(--blue-50) 0%, var(--white) 100%);
}
.pricing-hero h1 { margin-bottom: 12px; }
.pricing-hero p { color: var(--gray-500); font-size: 1.1rem; }

.pricing-cards { padding: 40px 0 80px; }
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  max-width: 720px;
  margin: 0 auto;
}
.price-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 32px;
  position: relative;
}
.price-card-featured {
  border-color: var(--blue-600);
  box-shadow: 0 0 0 1px var(--blue-600), var(--shadow-lg);
}
.price-card-badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--blue-600);
  color: var(--white);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: 99px;
  text-transform: uppercase;
}
.price-card-header { margin-bottom: 24px; }
.price-card-header h2 { margin-bottom: 8px; }
.price {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--gray-900);
}
.price span { font-size: 1rem; font-weight: 400; color: var(--gray-400); }

.price-features {
  list-style: none;
  margin-bottom: 32px;
}
.price-features li {
  padding: 6px 0;
  font-size: 0.9rem;
  color: var(--gray-600);
  padding-left: 24px;
  position: relative;
}
.price-features li.included::before {
  content: "\2713";
  position: absolute;
  left: 0;
  color: var(--green-500);
  font-weight: 700;
}
.price-features li.excluded::before {
  content: "\2717";
  position: absolute;
  left: 0;
  color: var(--gray-300);
}
.price-features li.excluded { color: var(--gray-400); }

/* === FAQ === */
.faq { padding: 60px 0 80px; background: var(--gray-50); }
.faq h2 { text-align: center; margin-bottom: 40px; }
.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  max-width: 800px;
  margin: 0 auto;
}
.faq-item h3 { margin-bottom: 8px; font-size: 1rem; }
.faq-item p { color: var(--gray-500); font-size: 0.9rem; }

/* === Blog === */
.blog-hero {
  padding: 60px 0 40px;
  text-align: center;
  background: linear-gradient(180deg, var(--blue-50) 0%, var(--white) 100%);
}
.blog-hero h1 { margin-bottom: 12px; }
.blog-hero p { color: var(--gray-500); font-size: 1.1rem; }

.blog-list { padding: 40px 0 80px; }
.blog-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  max-width: 720px;
  margin: 0 auto;
}
.blog-card {
  display: block;
  padding: 28px 32px;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  background: var(--white);
  color: var(--gray-800);
  transition: border-color 0.15s, box-shadow 0.15s;
}
.blog-card:hover {
  text-decoration: none;
  border-color: var(--blue-600);
  box-shadow: var(--shadow);
}
.blog-card-meta {
  font-size: 0.8rem;
  color: var(--gray-400);
  margin-bottom: 8px;
}
.blog-card h2 {
  font-size: 1.2rem;
  margin-bottom: 8px;
  color: var(--gray-900);
}
.blog-card p {
  color: var(--gray-500);
  font-size: 0.9rem;
  margin-bottom: 12px;
  line-height: 1.5;
}
.blog-card-link {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--blue-600);
}

/* Blog Post */
.blog-post { padding: 48px 0 80px; }
.blog-post-content {
  max-width: 680px;
  margin: 0 auto;
}
.blog-post-meta {
  font-size: 0.85rem;
  color: var(--gray-400);
  margin-bottom: 16px;
}
.blog-post-meta a { color: var(--blue-600); }
.blog-post-content h1 {
  font-size: 2rem;
  margin-bottom: 20px;
  line-height: 1.25;
}
.blog-post-intro {
  font-size: 1.1rem;
  color: var(--gray-600);
  line-height: 1.6;
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--gray-200);
}
.blog-post-content h2 {
  margin-top: 36px;
  margin-bottom: 12px;
  font-size: 1.3rem;
}
.blog-post-content p {
  color: var(--gray-600);
  margin-bottom: 14px;
  font-size: 0.95rem;
  line-height: 1.7;
}
.blog-post-content ul, .blog-post-content ol {
  color: var(--gray-600);
  margin-bottom: 14px;
  padding-left: 24px;
  font-size: 0.95rem;
  line-height: 1.7;
}
.blog-post-content li { margin-bottom: 6px; }
.blog-post-content a { color: var(--blue-600); }
.blog-post-content a.btn-primary { color: var(--white); }

.blog-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0 24px;
  font-size: 0.9rem;
}
.blog-table th {
  text-align: left;
  padding: 10px 12px;
  background: var(--gray-50);
  border-bottom: 2px solid var(--gray-200);
  font-weight: 600;
  color: var(--gray-700);
  font-size: 0.85rem;
}
.blog-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--gray-100);
  color: var(--gray-600);
}

.blog-cta {
  text-align: center;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--gray-200);
}

/* === Legal Pages === */
.legal { padding: 60px 0 80px; }
.legal-content { max-width: 720px; margin: 0 auto; }
.legal-content h1 { margin-bottom: 8px; }
.legal-updated { color: var(--gray-400); font-size: 0.85rem; margin-bottom: 32px; }
.legal-content h2 { margin-top: 32px; margin-bottom: 12px; font-size: 1.2rem; }
.legal-content h3 { margin-top: 20px; margin-bottom: 8px; font-size: 1rem; }
.legal-content p { color: var(--gray-600); margin-bottom: 12px; font-size: 0.95rem; }
.legal-content ul { color: var(--gray-600); margin-bottom: 12px; padding-left: 24px; font-size: 0.95rem; }
.legal-content li { margin-bottom: 6px; }

/* === Responsive === */
@media (max-width: 768px) {
  h1 { font-size: 1.8rem; }
  .hero { padding: 48px 0 40px; }
  .generator-layout { grid-template-columns: 1fr; }
  .preview-sticky { position: static; }
  .steps-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .use-cases-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: 1fr; max-width: 400px; }
  .faq-grid { grid-template-columns: 1fr; }
  .line-items-header,
  .line-item-row {
    grid-template-columns: 1fr 60px 70px 70px 32px;
  }
}