/* ========================================
   MK CEO — Design System
   Reference: Zapier, NerdWallet, G2
   ======================================== */

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

/* ---------- Design Tokens ---------- */
:root {
  --blue-50: #eff6ff;
  --blue-100: #dbeafe;
  --blue-500: #3b82f6;
  --blue-600: #2563eb;
  --blue-700: #1d4ed8;
  --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-900: #111827;
  --amber-500: #f59e0b;
  --green-500: #10b981;
  --red-500: #ef4444;

  --color-primary: var(--blue-600);
  --color-primary-hover: var(--blue-700);
  --color-primary-light: var(--blue-50);
  --color-accent: var(--amber-500);
  --color-success: var(--green-500);
  --color-text: var(--gray-900);
  --color-text-secondary: var(--gray-600);
  --color-text-muted: var(--gray-400);
  --color-bg: #ffffff;
  --color-bg-secondary: var(--gray-50);
  --color-bg-tertiary: var(--gray-100);
  --color-border: var(--gray-200);
  --color-border-light: var(--gray-100);
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 24px rgba(0,0,0,0.08);
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 14px;
  --content-w: 720px;
  --wide-w: 840px;
  --nav-h: 60px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding-top: var(--nav-h);
}

/* ---------- Skip Link (Accessibility) ---------- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 8px;
  padding: 8px 16px;
  background: var(--color-primary);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  z-index: 200;
  transition: top 0.15s;
}
.skip-link:focus {
  top: 0;
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ---------- Focus visible (accessibility) ---------- */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}
:focus:not(:focus-visible) {
  outline: none;
}

/* ---------- Utilities ---------- */
.container {
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 0 24px;
}

.container-wide {
  max-width: var(--wide-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ========================================
   NAVIGATION
   ======================================== */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-h);
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
}

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.nav-logo {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.nav-logo:hover {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.nav-links::-webkit-scrollbar {
  display: none;
}

.nav-links a {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  transition: background 0.15s, color 0.15s;
}

.nav-links a:hover,
.nav-links a.nav-active {
  background: var(--color-bg-secondary);
  color: var(--color-text);
}

.nav-links a.nav-active {
  color: var(--color-primary);
  font-weight: 600;
}

/* ========================================
   HERO
   ======================================== */
.hero {
  padding: 56px 0 48px;
  text-align: center;
  background: linear-gradient(180deg, var(--color-bg-secondary) 0%, var(--color-bg) 100%);
  border-bottom: 1px solid var(--color-border-light);
}

.hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  line-height: 1.15;
  color: var(--color-text);
}

.hero .subtitle {
  font-size: 1.1rem;
  color: var(--color-primary);
  font-weight: 500;
  margin-top: 6px;
}

.hero .tagline {
  font-size: 1rem;
  color: var(--color-text-secondary);
  margin-top: 12px;
  max-width: 520px;
  margin-left: auto;
  margin-right: auto;
}

/* ========================================
   HOMEPAGE CATEGORIES
   ======================================== */
.home-section {
  padding: 40px 0;
}

.home-section-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.category-grid {
  display: grid;
  gap: 16px;
}

@media (min-width: 640px) {
  .category-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.category-card {
  display: flex;
  flex-direction: column;
  padding: 24px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--color-text);
  transition: border-color 0.2s, box-shadow 0.2s, transform 0.15s;
}

.category-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.category-card h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 6px;
}

.category-card p {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
  flex: 1;
}

.category-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--color-border-light);
}

.article-count {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.category-arrow {
  font-size: 0.9rem;
  color: var(--color-primary);
  opacity: 0;
  transition: opacity 0.2s, transform 0.2s;
}

.category-card:hover .category-arrow {
  opacity: 1;
  transform: translateX(4px);
}

/* ========================================
   ARTICLE LIST (Homepage & Category)
   ======================================== */
.article-list {
  list-style: none;
}

.article-list li {
  padding: 0;
  border-bottom: 1px solid var(--color-border-light);
}

.article-list li:last-child {
  border-bottom: none;
}

.article-list a {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 18px 0;
  text-decoration: none;
  color: var(--color-text);
  transition: padding-left 0.15s;
}

.article-list a:hover {
  padding-left: 6px;
}

.article-list a:hover .article-title {
  color: var(--color-primary);
}

.article-title {
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.4;
  transition: color 0.15s;
}

.article-meta {
  font-size: 0.82rem;
  color: var(--color-text-muted);
}

/* ========================================
   ARTICLE PAGE
   ======================================== */

/* Breadcrumb */
.article-header {
  padding: 28px 0 12px;
}

.breadcrumb {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-bottom: 12px;
}

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

.breadcrumb a:hover {
  text-decoration: underline;
}

.article-header h1 {
  font-size: 1.85rem;
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.015em;
}

/* Byline */
.byline {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--color-border-light);
}

.byline-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
  flex-shrink: 0;
}

.byline-info {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

.byline-info strong {
  color: var(--color-text);
  font-weight: 600;
}

/* Article Content */
.article-content {
  font-size: 1.07rem;
  line-height: 1.85;
  padding: 32px 0 56px;
}

.article-content h2 {
  font-size: 1.4rem;
  font-weight: 700;
  margin: 44px 0 14px;
  padding-top: 4px;
}

.article-content h3 {
  font-size: 1.13rem;
  font-weight: 600;
  margin: 28px 0 10px;
  color: var(--color-text-secondary);
}

.article-content p {
  margin-bottom: 18px;
}

.article-content ul, .article-content ol {
  margin: 0 0 18px 24px;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.article-content a:hover {
  color: var(--color-primary-hover);
}

.article-content strong {
  font-weight: 700;
}

/* Article featured image */
.article-content .featured-image {
  border-radius: var(--radius);
  width: 100%;
  height: auto;
  aspect-ratio: 800 / 450;
  object-fit: cover;
  margin-bottom: 28px;
  display: block;
  background: var(--color-bg-tertiary);
}

/* ========================================
   TABLE OF CONTENTS
   ======================================== */
.toc {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 0 0 32px;
}

.toc-title {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  margin-bottom: 12px;
}

.toc-list {
  list-style: none;
  margin: 0;
}

.toc-list li {
  padding: 3px 0;
}

.toc-list a {
  font-size: 0.92rem;
  color: var(--color-primary);
  text-decoration: none;
  padding: 2px 0;
  display: inline-block;
}

.toc-list a:hover {
  text-decoration: underline;
}

/* ========================================
   COMPARISON TABLE
   ======================================== */
.table-wrapper {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 24px 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  min-width: 480px;
}

.compare-table th,
.compare-table td {
  text-align: left;
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
}

.compare-table th {
  background: var(--color-bg-secondary);
  font-weight: 700;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--color-text-secondary);
}

.compare-table tbody tr:nth-child(even) {
  background: var(--color-bg-secondary);
}

.compare-table tbody tr:hover {
  background: var(--color-primary-light);
}

.compare-table td:first-child {
  font-weight: 600;
  white-space: nowrap;
  color: var(--color-text);
}

/* Winner tag in table */
.winner-tag {
  display: inline-block;
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: #d1fae5;
  color: #065f46;
  padding: 2px 8px;
  border-radius: 20px;
  margin-left: 6px;
}

/* ========================================
   VERDICT BLOCKS
   ======================================== */
.verdict {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 20px 22px;
  margin: 24px 0;
  box-shadow: var(--shadow-sm);
}

.verdict strong {
  display: block;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--color-text);
}

.verdict-winner {
  border-left-color: var(--color-success);
}

.verdict-winner strong::after {
  content: " ✓ BEST CHOICE";
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--color-success);
  letter-spacing: 0.04em;
  margin-left: 8px;
}

/* ========================================
   PROS / CONS
   ======================================== */
.pros-cons {
  display: grid;
  gap: 16px;
  margin: 24px 0;
}

@media (min-width: 600px) {
  .pros-cons {
    grid-template-columns: 1fr 1fr;
  }
}

.pros, .cons {
  padding: 16px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
}

.pros {
  background: #f0fdf4;
}

.cons {
  background: #fef2f2;
}

.pros-title, .cons-title {
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.pros-title { color: #065f46; }
.cons-title { color: #991b1b; }

.pros ul, .cons ul {
  list-style: none;
  margin: 0;
}

.pros li, .cons li {
  font-size: 0.9rem;
  padding: 3px 0;
  margin: 0;
}

.pros li::before {
  content: "✓ ";
  color: var(--color-success);
  font-weight: 700;
}

.cons li::before {
  content: "✗ ";
  color: var(--red-500);
  font-weight: 700;
}

/* ========================================
   RELATED ARTICLES
   ======================================== */
.related-articles {
  margin: 40px 0 48px;
  padding-top: 32px;
  border-top: 1px solid var(--color-border);
}

.related-articles h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.related-grid {
  display: grid;
  gap: 12px;
}

@media (min-width: 600px) {
  .related-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.related-card {
  display: block;
  padding: 16px 20px;
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--color-text);
  transition: border-color 0.15s;
  font-size: 0.92rem;
  font-weight: 500;
}

.related-card:hover {
  border-color: var(--color-primary);
}

.related-card .related-meta {
  display: block;
  font-size: 0.78rem;
  font-weight: 400;
  color: var(--color-text-muted);
  margin-top: 4px;
}

/* ========================================
   BACK TO TOP
   ======================================== */
.back-to-top {
  text-align: center;
  margin: 8px 0 24px;
}

.back-to-top a {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  text-decoration: none;
  padding: 6px 16px;
  border: 1px solid var(--color-border);
  border-radius: 20px;
  transition: background 0.15s, color 0.15s;
}

.back-to-top a:hover {
  background: var(--color-bg-secondary);
  color: var(--color-text);
}

/* ========================================
   HR & DISCLOSURE
   ======================================== */
.article-content hr {
  margin: 40px 0;
  border: none;
  border-top: 1px solid var(--color-border);
}

.article-disclosure {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* ========================================
   CATEGORY PAGE
   ======================================== */
.category-header {
  padding: 36px 0 24px;
}

.category-header h1 {
  font-size: 1.75rem;
  font-weight: 800;
  margin-top: 8px;
}

.category-header .tagline {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  margin-top: 6px;
}

/* ========================================
   FOOTER
   ======================================== */
.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--color-border);
  padding: 32px 0;
  text-align: center;
  background: var(--color-bg-secondary);
}

.footer-brand {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--color-text);
}

.footer-tagline {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-top: 2px;
}

.footer-disclaimer {
  margin-top: 10px;
  font-size: 0.75rem;
  color: var(--color-text-muted);
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

/* ========================================
   RESPONSIVE
   ======================================== */
@media (max-width: 640px) {
  body {
    padding-top: var(--nav-h);
  }

  .hero {
    padding: 36px 0 32px;
  }
  .hero h1 {
    font-size: 1.7rem;
  }
  .hero .subtitle {
    font-size: 1rem;
  }

  .article-header h1 {
    font-size: 1.35rem;
  }
  .article-content {
    font-size: 1rem;
  }
  .article-content h2 {
    font-size: 1.2rem;
  }

  .container {
    padding: 0 16px;
  }
  .container-wide {
    padding: 0 16px;
  }
  .nav-inner {
    padding: 0 16px;
  }

  .verdict {
    padding: 14px 16px;
  }
  .toc {
    padding: 14px 16px;
  }

  .byline {
    flex-wrap: wrap;
  }

  .category-card {
    padding: 18px;
  }

  .pros-cons {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   404 PAGE
   ======================================== */
.page-404 {
  text-align: center;
  padding: 100px 0;
}

.page-404 h1 {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--color-primary);
  line-height: 1;
}

.page-404 p {
  color: var(--color-text-secondary);
  margin: 16px 0 24px;
  font-size: 1.05rem;
}

.back-home {
  display: inline-block;
  padding: 10px 24px;
  background: var(--color-primary);
  color: #fff;
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.92rem;
  transition: background 0.15s;
}

.back-home:hover {
  background: var(--color-primary-hover);
}