/* =========================================================================
   Sudoku SB — Marketing / Content Site Stylesheet
   Shared by the homepage and every SEO content page (/daily-sudoku,
   /easy-sudoku, /how-to-play-sudoku, etc). Deliberately lean — no game
   board or overlay rules live here, so these pages stay fast. Uses the
   same brand palette as the game (play/css/styles.css) for consistency.
   ========================================================================= */

:root {
  --purple-900: #241148;
  --purple-800: #2b1a5e;
  --purple-700: #3d2472;
  --purple-600: #4f2f96;
  --purple-500: #6c3fc9;
  --gold-500: #e8b84b;
  --gold-400: #f3cd6e;
  --cream-100: #fbf7ef;
  --cream-200: #f4ecdb;
  --white: #ffffff;
  --navy-900: #10142b;
  --green-500: #2fa870;
  --red-500: #e0605a;

  --bg: var(--cream-100);
  --bg-elevated: var(--white);
  --text-primary: #241a3d;
  --text-secondary: #6a6079;
  --card-shadow: 0 10px 30px rgba(43, 26, 94, 0.12);
  --card-shadow-sm: 0 4px 14px rgba(43, 26, 94, 0.08);
  --border-soft: rgba(43, 26, 94, 0.08);
  --accent: var(--purple-600);
  --accent-strong: var(--purple-700);
  --radius-lg: 22px;
  --radius-md: 16px;
  --radius-sm: 10px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'Segoe UI', system-ui, -apple-system, 'Noto Sans', Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
}
a { color: var(--accent-strong); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 12px; color: var(--purple-800); }
p { margin: 0 0 14px; }
ul, ol { margin: 0 0 14px; padding-left: 22px; }
li { margin-bottom: 6px; }
.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 20px;
}
.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
}
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--purple-800);
  color: white;
  padding: 10px 16px;
  border-radius: 0 0 10px 0;
  z-index: 999;
}
.skip-link:focus { left: 0; }

/* ---------------------------------------------------------------------
   Header / nav
   --------------------------------------------------------------------- */
.site-header {
  background: linear-gradient(135deg, var(--purple-800), var(--purple-600));
  padding: 14px 0;
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: 0 2px 14px rgba(0,0,0,0.15);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.brand-link { display: flex; flex-direction: column; color: white; }
.brand-link:hover { text-decoration: none; }
.brand-link .brand-name { font-size: 22px; font-weight: 800; letter-spacing: 0.3px; }
.brand-link .brand-name span { color: var(--gold-400); }
.brand-link .brand-sub { font-size: 10.5px; letter-spacing: 2.5px; color: rgba(255,255,255,0.72); text-transform: lowercase; margin-top: -2px; }

.nav-toggle {
  display: none;
  background: rgba(255,255,255,0.14);
  border: 1px solid rgba(255,255,255,0.3);
  color: white;
  border-radius: 10px;
  padding: 8px 12px;
  font-size: 18px;
  line-height: 1;
}
.site-nav { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; }
.site-nav a {
  color: rgba(255,255,255,0.88);
  font-size: 13.5px;
  font-weight: 600;
  padding: 8px 12px;
  border-radius: 999px;
  transition: background 160ms ease;
}
.site-nav a:hover { background: rgba(255,255,255,0.12); text-decoration: none; }
.nav-cta {
  background: linear-gradient(135deg, var(--gold-500), var(--gold-400)) !important;
  color: #2b1a04 !important;
  font-weight: 800 !important;
}

/* ---------------------------------------------------------------------
   Hero (homepage)
   --------------------------------------------------------------------- */
.hero {
  background: linear-gradient(180deg, #1b1140 0%, #2b1a5e 45%, #4a2e86 100%);
  color: white;
  padding: 56px 0 64px;
  text-align: center;
}
.hero h1 { color: white; font-size: 34px; margin-bottom: 14px; }
.hero .lede { color: rgba(255,255,255,0.88); font-size: 17px; max-width: 620px; margin: 0 auto 26px; }
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin-bottom: 10px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  border-radius: var(--radius-md);
  padding: 15px 28px;
  font-size: 15.5px;
  font-weight: 800;
  letter-spacing: 0.3px;
  cursor: pointer;
  transition: transform 150ms ease, box-shadow 150ms ease;
}
.btn:hover { transform: translateY(-1px); text-decoration: none; }
.btn-primary {
  background: linear-gradient(135deg, var(--gold-500), var(--gold-400));
  color: #2b1a04;
  box-shadow: 0 8px 22px rgba(232, 184, 75, 0.35);
}
.btn-secondary {
  background: rgba(255,255,255,0.14);
  color: white;
  border: 1.5px solid rgba(255,255,255,0.4);
}
.btn-outline {
  background: var(--bg-elevated);
  color: var(--accent-strong);
  border: 1.5px solid var(--border-soft);
  box-shadow: var(--card-shadow-sm);
}
.daily-nudge {
  margin-top: 22px;
  display: inline-block;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.25);
  border-radius: 999px;
  padding: 10px 20px;
  font-size: 13.5px;
  color: white;
}

/* ---------------------------------------------------------------------
   Sections / cards
   --------------------------------------------------------------------- */
.section { padding: 48px 0; }
.section-alt { background: var(--bg-elevated); }
.section h2 { font-size: 25px; text-align: center; margin-bottom: 8px; }
.section .section-sub { text-align: center; color: var(--text-secondary); max-width: 620px; margin: 0 auto 30px; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}
.feature-card {
  background: var(--bg-elevated);
  border-radius: var(--radius-md);
  box-shadow: var(--card-shadow-sm);
  padding: 22px 18px;
}
.feature-card .icon { font-size: 26px; margin-bottom: 8px; display: block; }
.feature-card h3 { font-size: 16px; margin-bottom: 6px; }
.feature-card p { font-size: 13.5px; color: var(--text-secondary); margin: 0; }

.link-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 12px;
}
.link-card {
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  box-shadow: var(--card-shadow-sm);
  padding: 16px 18px;
  color: var(--text-primary);
  display: block;
}
.link-card:hover { box-shadow: var(--card-shadow); text-decoration: none; }
.link-card .link-title { font-weight: 800; color: var(--accent-strong); font-size: 14.5px; display: block; margin-bottom: 3px; }
.link-card .link-desc { font-size: 12.5px; color: var(--text-secondary); }

/* ---------------------------------------------------------------------
   Article-style content pages
   --------------------------------------------------------------------- */
.breadcrumbs {
  font-size: 12.5px;
  color: var(--text-secondary);
  padding: 16px 0 0;
}
.breadcrumbs a { color: var(--text-secondary); }
.breadcrumbs .sep { margin: 0 6px; }

.article-header { padding: 24px 0 8px; }
.article-header h1 { font-size: 28px; }
.article-header .article-lede { font-size: 15.5px; color: var(--text-secondary); }

.article-body { padding-bottom: 8px; }
.article-body h2 { font-size: 20px; margin-top: 30px; }
.article-body h3 { font-size: 16.5px; margin-top: 20px; }
.article-body p, .article-body li { font-size: 15px; color: var(--text-primary); }

.cta-band {
  background: linear-gradient(135deg, var(--purple-800), var(--purple-600));
  color: white;
  border-radius: var(--radius-lg);
  padding: 34px 26px;
  text-align: center;
  margin: 32px 0;
}
.cta-band h2 { color: white; margin-bottom: 8px; }
.cta-band p { color: rgba(255,255,255,0.85); margin-bottom: 18px; }

.diff-badge {
  display: inline-block;
  background: var(--gold-500);
  color: #2b1a04;
  font-weight: 800;
  font-size: 12px;
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 14px;
}

/* ---------------------------------------------------------------------
   FAQ
   --------------------------------------------------------------------- */
.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-item {
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  box-shadow: var(--card-shadow-sm);
  padding: 4px 20px;
}
.faq-item summary {
  cursor: pointer;
  font-weight: 700;
  padding: 16px 0;
  font-size: 15px;
  list-style: none;
  position: relative;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: '+';
  position: absolute;
  right: 0;
  top: 14px;
  font-size: 20px;
  color: var(--accent-strong);
}
.faq-item[open] summary::after { content: '−'; }
.faq-item p { padding-bottom: 16px; color: var(--text-secondary); font-size: 14px; margin: 0; }

/* ---------------------------------------------------------------------
   Footer
   --------------------------------------------------------------------- */
.site-footer {
  background: var(--navy-900);
  color: rgba(255,255,255,0.7);
  padding: 40px 0 28px;
  margin-top: 24px;
}
.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 24px;
  margin-bottom: 24px;
}
.footer-grid h4 { color: white; font-size: 13px; text-transform: uppercase; letter-spacing: 0.6px; margin-bottom: 10px; }
.footer-grid a { color: rgba(255,255,255,0.68); font-size: 13.5px; display: block; margin-bottom: 8px; }
.footer-grid a:hover { color: white; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.12);
  padding-top: 20px;
  text-align: center;
  font-size: 12.5px;
}
.footer-bottom .heart { color: #ff8fa3; }

@media (max-width: 780px) {
  .nav-toggle { display: inline-flex; align-items: center; justify-content: center; }
  .site-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    order: 3;
    margin-top: 10px;
  }
  .site-nav.open { display: flex; }
  .site-nav a { padding: 12px 14px; }
  .hero h1 { font-size: 27px; }
}