/*
Theme Name: Superbuy Spreadsheet
Theme URI: https://sheetcn.com/
Author: SheetCN
Author URI: https://sheetcn.com/
Description: SEO-optimized dark theme for Superbuy Spreadsheet product links and guides.
Version: 1.0.0
Requires at least: 6.0
Tested up to: 6.7
License: GPL v2 or later
Tags: seo, dark, one-column, custom-menu
Text Domain: superbuy-spreadsheet
*/

/* === TOKENS === */
:root {
  --bg:        #0f0f0f;
  --surface:   #191919;
  --surface2:  #222222;
  --border:    #2e2e2e;
  --accent:    #e53e3e;
  --accent-h:  #c53030;
  --accent-bg: #1c0808;
  --text:      #f0ede8;
  --muted:     #959595;
  --radius:    8px;
  --radius-lg: 14px;
  --max-w:     1200px;
  --gap:       20px;
}

/* === RESET === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

/* === LAYOUT === */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 var(--gap); }
.section { padding: 60px 0; }
.section + .section { padding-top: 0; }

/* === NAV === */
#site-nav {
  background: #0a0a0a;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 200;
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 62px;
  gap: 16px;
}
.site-logo {
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -.3px;
  white-space: nowrap;
  flex-shrink: 0;
}
.site-logo span { color: var(--accent); }

/* Primary menu */
#primary-menu {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
  flex-wrap: nowrap;
}
#primary-menu > li { position: relative; }
#primary-menu > li > a,
#primary-menu > li > button {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 7px 13px;
  border-radius: var(--radius);
  font-size: .82rem;
  font-weight: 500;
  color: var(--muted);
  background: none;
  border: none;
  cursor: pointer;
  white-space: nowrap;
  transition: color .15s, background .15s;
  font-family: inherit;
}
#primary-menu > li > a:hover,
#primary-menu > li > button:hover { color: var(--text); background: var(--surface); }
#primary-menu > li > button::after { content: '▾'; font-size: .65rem; }

/* Dropdown */
.sub-menu {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  min-width: 210px;
  padding: 6px;
  list-style: none;
  box-shadow: 0 10px 30px rgba(0,0,0,.55);
  z-index: 300;
}
.menu-item-has-children:hover > .sub-menu,
.menu-item-has-children:focus-within > .sub-menu { display: block; }
.sub-menu li a {
  display: block;
  padding: 9px 12px;
  font-size: .82rem;
  color: var(--muted);
  border-radius: 6px;
  transition: color .15s, background .15s;
}
.sub-menu li a:hover { color: var(--text); background: var(--surface2); }

/* Nav CTA */
.nav-cta > a,
a.nav-cta {
  background: var(--accent) !important;
  color: #fff !important;
  font-weight: 700 !important;
  border-radius: var(--radius) !important;
  padding: 7px 16px !important;
  transition: background .15s !important;
}
.nav-cta > a:hover,
a.nav-cta:hover { background: var(--accent-h) !important; }

/* Mobile toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.4rem;
  cursor: pointer;
  padding: 6px;
}

/* === HERO === */
.hero {
  background: linear-gradient(155deg, #1c0909 0%, #0f0f0f 55%);
  padding: 90px var(--gap) 72px;
  text-align: center;
}
.hero-tag {
  display: inline-block;
  background: var(--accent-bg);
  border: 1px solid var(--accent);
  color: var(--accent);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 22px;
}
.hero h1 {
  font-size: clamp(2rem, 5.5vw, 3.4rem);
  font-weight: 800;
  line-height: 1.12;
  max-width: 780px;
  margin: 0 auto 18px;
  letter-spacing: -.5px;
}
.hero h1 span { color: var(--accent); }
.hero-desc {
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 560px;
  margin: 0 auto 38px;
}
.hero-btns {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* === BUTTONS === */
.btn-primary {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 14px 32px;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: .95rem;
  transition: background .15s, transform .12s;
}
.btn-primary:hover { background: var(--accent-h); transform: translateY(-1px); color: #fff; }
.btn-outline {
  display: inline-block;
  border: 1.5px solid var(--border);
  color: var(--text);
  padding: 13px 28px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: .95rem;
  transition: border-color .15s, background .15s;
}
.btn-outline:hover { border-color: var(--accent); background: var(--accent-bg); color: var(--text); }

/* === STATS BAR === */
.stats-bar {
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 28px var(--gap);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
}
.stat-num { font-size: 1.65rem; font-weight: 800; color: var(--accent); }
.stat-label { font-size: .78rem; color: var(--muted); margin-top: 3px; }

/* === SECTION HEADING === */
.section-head { margin-bottom: 32px; }
.section-head h2 { font-size: 1.55rem; font-weight: 800; margin-bottom: 6px; }
.section-head p { color: var(--muted); font-size: .9rem; }

/* === CATEGORY GRID === */
.cat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 14px;
}
.cat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px 18px;
  display: flex;
  align-items: center;
  gap: 14px;
  transition: border-color .15s, background .15s, transform .15s;
}
.cat-card:hover {
  border-color: var(--accent);
  background: var(--surface2);
  transform: translateY(-2px);
}
.cat-icon {
  width: 46px;
  height: 46px;
  background: var(--accent-bg);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}
.cat-name { font-weight: 700; font-size: .88rem; }
.cat-sub  { font-size: .74rem; color: var(--muted); margin-top: 2px; }

/* === ARTICLE BOX === */
.article-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px 44px;
}
.article-label {
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--accent);
  margin-bottom: 12px;
}
.article-box h2 { font-size: 1.65rem; font-weight: 800; margin-bottom: 18px; line-height: 1.3; }
.article-box h3 { font-size: 1.05rem; font-weight: 700; margin: 24px 0 8px; color: var(--text); }
.article-box p  { color: var(--muted); line-height: 1.78; margin-bottom: 14px; font-size: .93rem; }
.article-box p strong { color: var(--text); }
.article-box a  { color: var(--accent); }
.article-box a:hover { text-decoration: underline; }
.article-btns { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 30px; }

/* === GUIDE CARDS === */
.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
  gap: 18px;
}
.guide-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 26px;
  transition: border-color .15s, transform .15s;
  display: flex;
  flex-direction: column;
}
.guide-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.guide-badge {
  display: inline-block;
  background: var(--accent-bg);
  color: var(--accent);
  font-size: .7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 14px;
  width: fit-content;
}
.guide-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 10px; line-height: 1.38; }
.guide-card p  { font-size: .83rem; color: var(--muted); flex: 1; margin-bottom: 20px; }
.guide-link {
  font-size: .82rem;
  font-weight: 700;
  color: var(--accent);
  display: flex;
  align-items: center;
  gap: 5px;
}
.guide-link::after { content: '→'; }
.guide-link:hover { text-decoration: underline; }

/* === SINGLE POST / PAGE === */
.post-wrap { max-width: 800px; margin: 0 auto; padding: 56px var(--gap); }
.post-header { margin-bottom: 32px; }
.post-badge {
  display: inline-block;
  background: var(--accent-bg);
  color: var(--accent);
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 14px;
}
.post-header h1 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); font-weight: 800; line-height: 1.2; margin-bottom: 12px; }
.post-meta { font-size: .8rem; color: var(--muted); }
.post-content { line-height: 1.78; }
.post-content h2 { font-size: 1.35rem; font-weight: 700; margin: 32px 0 10px; }
.post-content h3 { font-size: 1.1rem; font-weight: 700; margin: 24px 0 8px; }
.post-content p  { color: var(--muted); margin-bottom: 16px; font-size: .94rem; }
.post-content p strong { color: var(--text); }
.post-content a  { color: var(--accent); }
.post-content a:hover { text-decoration: underline; }
.post-content ul, .post-content ol { padding-left: 1.5rem; margin-bottom: 16px; color: var(--muted); font-size: .94rem; }
.post-content li { margin-bottom: 6px; }
.internal-links {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  margin: 36px 0;
}
.internal-links h4 { font-size: .85rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); margin-bottom: 14px; }
.internal-links ul { list-style: none; padding: 0; margin: 0; }
.internal-links ul li { margin-bottom: 8px; }
.internal-links ul li a { font-size: .88rem; color: var(--accent); }
.internal-links ul li a:hover { text-decoration: underline; }
.back-home { margin-top: 32px; }

/* === FOOTER === */
#site-footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 48px 0 24px;
  margin-top: 48px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 36px;
}
.footer-about-text { font-size: .83rem; color: var(--muted); margin-top: 12px; line-height: 1.72; }
.footer-col h4 {
  font-size: .78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--muted);
  margin-bottom: 14px;
}
.footer-col a { display: block; font-size: .83rem; color: var(--muted); margin-bottom: 9px; transition: color .15s; }
.footer-col a:hover { color: var(--text); }
.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 22px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}
.footer-bottom p { font-size: .78rem; color: var(--muted); }
.footer-bottom a { color: var(--accent); }

/* === RESPONSIVE === */
@media (max-width: 900px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid .footer-about { grid-column: 1 / -1; }
  .guide-grid { grid-template-columns: 1fr; }
}
@media (max-width: 680px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .article-box { padding: 24px 20px; }
  .nav-toggle { display: flex; }
  #primary-menu {
    display: none;
    position: absolute;
    top: 62px;
    left: 0;
    right: 0;
    background: #0a0a0a;
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: stretch;
    padding: 12px;
    gap: 2px;
  }
  #primary-menu.is-open { display: flex; }
  #primary-menu > li > a,
  #primary-menu > li > button { font-size: .9rem; padding: 10px 14px; }
  .sub-menu { position: static; border: none; background: var(--surface2); box-shadow: none; margin-top: 2px; }
}
@media (max-width: 480px) {
  .cat-grid { grid-template-columns: 1fr 1fr; }
  .hero { padding: 60px var(--gap) 48px; }
}