/*
Theme Name: Usfans Spreadsheet
Theme URI: https://sheetcn.com/
Author: Usfans
Author URI: https://sheetcn.com/
Description: Light, bright, and multi-color SEO-optimized WordPress theme for the Usfans Spreadsheet brand. Features a category dropdown, product category buttons with illustrated icons, and CTA buttons that drive traffic to sheetcn.com.
Version: 1.0.0
Requires at least: 5.5
Requires PHP: 7.2
License: GNU General Public License v2 or later
License URI: http://www.gnu.org/licenses/gpl-2.0.html
Text Domain: usfans-spreadsheet
Tags: seo, blog, one-column, two-columns, custom-menu, featured-images, threaded-comments
*/

/* ---------- Reset & Base ---------- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:'Nunito','Inter','Helvetica Neue',Arial,'PingFang SC','Microsoft YaHei',sans-serif;
  font-size:16px;line-height:1.7;color:#3d3650;
  background:
    radial-gradient(1200px 600px at 10% -10%, #ffe5f1 0%, transparent 60%),
    radial-gradient(1000px 500px at 90% 0%, #e0f2ff 0%, transparent 55%),
    radial-gradient(900px 500px at 50% 100%, #fff5e0 0%, transparent 55%),
    #fdfcff;
  background-attachment: fixed;
  -webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;
}
img{max-width:100%;height:auto;display:block}
a{color:#ff6b9d;text-decoration:none;transition:color .2s ease}
a:hover{color:#e63d7e;text-decoration:underline}
h1,h2,h3,h4,h5,h6{font-family:'Nunito','Inter',sans-serif;line-height:1.25;color:#2a2340;margin:0 0 .75em;font-weight:800;letter-spacing:-.01em}
h1{font-size:2.4rem}
h2{font-size:1.85rem;margin-top:1.5em}
h3{font-size:1.4rem;margin-top:1.2em}
p{margin:0 0 1em}
ul,ol{margin:0 0 1em 1.5em}
li{margin-bottom:.4em}
blockquote{border-left:4px solid #ffb3d1;background:#fff5fa;padding:1em 1.25em;margin:1.25em 0;font-style:italic;color:#6a5a7a;border-radius:0 12px 12px 0}
code{background:#f4edff;padding:2px 6px;border-radius:4px;font-size:.92em;color:#8b5cf6}

/* ---------- Layout ---------- */
.container{max-width:1200px;margin:0 auto;padding:0 24px}
.site-wrapper{min-height:100vh;display:flex;flex-direction:column}
main{flex:1}

/* ---------- Header ---------- */
.site-header{
  background:rgba(255,255,255,.85);
  backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
  border-bottom:1px solid rgba(255,215,230,.6);
  position:sticky;top:0;z-index:1000;
  box-shadow:0 2px 20px rgba(255,107,157,.08);
}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:16px 0;gap:24px;flex-wrap:wrap}
.site-branding a{display:flex;align-items:center;gap:12px;color:#2a2340;text-decoration:none}
.site-branding a:hover{text-decoration:none}
.site-logo{
  width:44px;height:44px;
  background:linear-gradient(135deg,#ff6b9d 0%,#ffb86c 50%,#8ecae6 100%);
  border-radius:14px;display:flex;align-items:center;justify-content:center;
  color:#fff;font-weight:900;font-size:1.15rem;
  box-shadow:0 6px 16px rgba(255,107,157,.3);
}
.site-title{font-size:1.4rem;font-weight:900;letter-spacing:-.015em;background:linear-gradient(135deg,#ff6b9d,#8b5cf6);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.site-tagline{font-size:.78rem;color:#8b7fa0;font-weight:600;margin-top:-2px}

/* Nav */
.main-nav{display:flex;align-items:center;gap:8px}
.main-nav ul{list-style:none;margin:0;padding:0;display:flex;gap:4px;align-items:center}
.main-nav li{margin:0}
.main-nav a{
  display:inline-block;padding:10px 16px;color:#5a4e72;font-weight:700;font-size:.95rem;border-radius:10px;
}
.main-nav a:hover{background:#fff0f6;color:#ff6b9d;text-decoration:none}

/* Dropdown */
.has-dropdown{position:relative}
.dropdown-toggle{
  background:linear-gradient(135deg,#ff6b9d,#8b5cf6);
  color:#fff !important;padding:10px 20px;border-radius:999px;cursor:pointer;
  display:inline-flex;align-items:center;gap:6px;border:none;font-weight:700;font-size:.95rem;
  box-shadow:0 4px 14px rgba(139,92,246,.3);
}
.dropdown-toggle:hover{transform:translateY(-1px);box-shadow:0 6px 18px rgba(139,92,246,.4);color:#fff !important}
.dropdown-toggle::after{content:'▾';font-size:.75rem;transition:transform .2s}
.has-dropdown:hover .dropdown-toggle::after,
.has-dropdown.open .dropdown-toggle::after{transform:rotate(180deg)}
.dropdown-menu{
  position:absolute;top:calc(100% + 10px);right:0;min-width:260px;
  background:#fff;border:1px solid #ffe0ec;border-radius:16px;
  box-shadow:0 20px 50px rgba(139,92,246,.15);
  padding:10px;opacity:0;visibility:hidden;transform:translateY(-8px);transition:all .2s ease;
  z-index:1100;
}
.has-dropdown:hover .dropdown-menu,
.has-dropdown.open .dropdown-menu,
.has-dropdown:focus-within .dropdown-menu{opacity:1;visibility:visible;transform:translateY(0)}
.dropdown-menu li{display:block}
.dropdown-menu a{
  display:flex;align-items:center;gap:10px;padding:10px 14px;color:#4a3f5e;font-weight:600;font-size:.95rem;border-radius:10px;
}
.dropdown-menu a:hover{background:linear-gradient(135deg,#fff0f6,#f0e9ff);color:#ff6b9d;text-decoration:none}

/* ---------- Hero ---------- */
.hero{
  padding:90px 0 80px;position:relative;overflow:hidden;
}
.hero::before{
  content:'';position:absolute;top:10%;right:-5%;width:420px;height:420px;
  background:radial-gradient(circle,rgba(255,184,108,.25),transparent 70%);
  border-radius:50%;z-index:0;
}
.hero::after{
  content:'';position:absolute;bottom:-15%;left:-10%;width:500px;height:500px;
  background:radial-gradient(circle,rgba(142,202,230,.22),transparent 70%);
  border-radius:50%;z-index:0;
}
.hero-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:48px;align-items:center;position:relative;z-index:2}
.hero-inner{max-width:620px}
.hero-badge{display:inline-flex;align-items:center;gap:6px;background:#fff;border:2px solid #ffd1e0;color:#ff6b9d;padding:7px 16px;border-radius:999px;font-size:.85rem;font-weight:800;margin-bottom:22px;letter-spacing:.02em;box-shadow:0 4px 14px rgba(255,107,157,.12)}
.hero h1{font-size:3.4rem;color:#2a2340;line-height:1.1;margin-bottom:22px;letter-spacing:-.02em;font-weight:900}
.hero h1 .accent{background:linear-gradient(135deg,#ff6b9d 0%,#ffb86c 50%,#8b5cf6 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero-sub{font-size:1.2rem;color:#6a5a7a;margin-bottom:34px;line-height:1.65}
.hero-ctas{display:flex;gap:14px;flex-wrap:wrap}

/* Hero illustration */
.hero-art{position:relative;height:420px}
.hero-art .blob{position:absolute;border-radius:50%;filter:blur(2px);opacity:.9}
.hero-art .b1{width:200px;height:200px;background:linear-gradient(135deg,#ffb3d1,#ff6b9d);top:30px;left:40px;animation:float 6s ease-in-out infinite}
.hero-art .b2{width:160px;height:160px;background:linear-gradient(135deg,#ffd59e,#ffb86c);top:120px;right:30px;animation:float 7s ease-in-out infinite .5s}
.hero-art .b3{width:140px;height:140px;background:linear-gradient(135deg,#a5d8ff,#8ecae6);bottom:40px;left:120px;animation:float 8s ease-in-out infinite 1s}
.hero-art .b4{width:120px;height:120px;background:linear-gradient(135deg,#d0bfff,#8b5cf6);top:40px;right:140px;animation:float 7.5s ease-in-out infinite .3s}
.hero-art .shopper{
  position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  width:260px;height:260px;z-index:3;
  background:#fff;border-radius:50%;
  display:flex;align-items:center;justify-content:center;font-size:7rem;
  box-shadow:0 30px 60px rgba(139,92,246,.2);
  animation:bob 5s ease-in-out infinite;
}
@keyframes float{0%,100%{transform:translateY(0) rotate(0)}50%{transform:translateY(-20px) rotate(5deg)}}
@keyframes bob{0%,100%{transform:translate(-50%,-50%)}50%{transform:translate(-50%,-54%)}}

/* ---------- Buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:15px 30px;border-radius:999px;font-weight:800;font-size:1rem;
  text-decoration:none;transition:all .25s ease;border:2px solid transparent;cursor:pointer;
  line-height:1;letter-spacing:.01em;
}
.btn-primary{background:linear-gradient(135deg,#ff6b9d,#ff85b8);color:#fff;box-shadow:0 8px 24px rgba(255,107,157,.35)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 12px 30px rgba(255,107,157,.5);color:#fff;text-decoration:none}
.btn-secondary{background:linear-gradient(135deg,#ffd59e,#ffb86c);color:#7a4a1a;box-shadow:0 8px 24px rgba(255,184,108,.35)}
.btn-secondary:hover{transform:translateY(-2px);box-shadow:0 12px 30px rgba(255,184,108,.5);color:#5a3410;text-decoration:none}
.btn-outline{background:#fff;color:#8b5cf6;border-color:#d0bfff}
.btn-outline:hover{background:#8b5cf6;color:#fff;border-color:#8b5cf6;text-decoration:none}

/* ---------- Section ---------- */
.section{padding:80px 0;position:relative}
.section-alt{background:rgba(255,255,255,.5);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px)}
.section-header{text-align:center;max-width:720px;margin:0 auto 54px}
.section-header .eyebrow{color:#ff6b9d;font-weight:800;font-size:.88rem;text-transform:uppercase;letter-spacing:.12em;margin-bottom:10px;display:inline-block}
.section-header h2{font-size:2.5rem;margin-bottom:14px;font-weight:900}
.section-header p{color:#6a5a7a;font-size:1.1rem}

/* ---------- Category Grid ---------- */
.category-grid{
  display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));
  gap:22px;
}
.category-card{
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  background:#fff;border:2px solid transparent;border-radius:20px;padding:32px 20px 24px;text-align:center;
  color:#2a2340;font-weight:700;transition:all .3s ease;text-decoration:none;
  min-height:200px;position:relative;overflow:hidden;
  box-shadow:0 6px 20px rgba(139,92,246,.06);
}
.category-card::before{
  content:'';position:absolute;top:0;left:0;right:0;height:70px;opacity:.55;
  transition:all .3s ease;
}
.category-card:nth-child(1)::before{background:linear-gradient(135deg,#ffd1e0,#ffb3d1)}
.category-card:nth-child(2)::before{background:linear-gradient(135deg,#d0bfff,#b4a0ff)}
.category-card:nth-child(3)::before{background:linear-gradient(135deg,#a5d8ff,#8ecae6)}
.category-card:nth-child(4)::before{background:linear-gradient(135deg,#ffd59e,#ffb86c)}
.category-card:nth-child(5)::before{background:linear-gradient(135deg,#c3f0ca,#8ee5a2)}
.category-card:nth-child(6)::before{background:linear-gradient(135deg,#fff2a8,#ffe066)}
.category-card:nth-child(7)::before{background:linear-gradient(135deg,#ffcfd2,#ffa8ad)}
.category-card:nth-child(8)::before{background:linear-gradient(135deg,#c5f0ec,#8de4df)}
.category-card:hover{
  transform:translateY(-6px);border-color:#ffd1e0;
  box-shadow:0 20px 40px rgba(255,107,157,.18);text-decoration:none;color:#2a2340;
}
.category-card:hover::before{height:100%;opacity:.15}
.category-icon{
  width:84px;height:84px;border-radius:50%;
  background:#fff;
  display:flex;align-items:center;justify-content:center;
  margin-bottom:16px;position:relative;z-index:2;
  box-shadow:0 8px 24px rgba(0,0,0,.08);
  transition:all .3s ease;
}
.category-icon svg{width:48px;height:48px}
.category-card:hover .category-icon{transform:scale(1.08) rotate(-5deg)}
.category-name{font-size:1.1rem;font-weight:800;margin-bottom:4px;position:relative;z-index:2}
.category-meta{font-size:.82rem;color:#8b7fa0;font-weight:600;position:relative;z-index:2}
.category-card:hover .category-meta{color:#ff6b9d}

/* ---------- Article Cards ---------- */
.article-grid{
  display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));
  gap:26px;
}
.article-card{
  background:#fff;border:1px solid rgba(255,215,230,.5);border-radius:20px;overflow:hidden;
  transition:all .3s ease;display:flex;flex-direction:column;
  box-shadow:0 8px 24px rgba(139,92,246,.06);
}
.article-card:hover{transform:translateY(-6px);box-shadow:0 20px 40px rgba(255,107,157,.15)}
.article-card-thumb{
  height:170px;position:relative;overflow:hidden;
  display:flex;align-items:center;justify-content:center;
  color:#fff;font-size:3rem;font-weight:900;
  text-shadow:0 2px 10px rgba(0,0,0,.15);
}
.article-card:nth-child(6n+1) .article-card-thumb{background:linear-gradient(135deg,#ff6b9d,#ffb86c)}
.article-card:nth-child(6n+2) .article-card-thumb{background:linear-gradient(135deg,#8b5cf6,#a5d8ff)}
.article-card:nth-child(6n+3) .article-card-thumb{background:linear-gradient(135deg,#ffb86c,#fff2a8)}
.article-card:nth-child(6n+4) .article-card-thumb{background:linear-gradient(135deg,#8ee5a2,#a5d8ff)}
.article-card:nth-child(6n+5) .article-card-thumb{background:linear-gradient(135deg,#ff85b8,#d0bfff)}
.article-card:nth-child(6n) .article-card-thumb{background:linear-gradient(135deg,#8de4df,#ffd59e)}
.article-card-thumb::after{
  content:'';position:absolute;top:-50%;left:-50%;width:200%;height:200%;
  background:radial-gradient(circle at 30% 30%,rgba(255,255,255,.35),transparent 50%);
}
.article-card-body{padding:24px;flex:1;display:flex;flex-direction:column}
.article-card .tag{display:inline-block;background:linear-gradient(135deg,#fff0f6,#f0e9ff);color:#8b5cf6;padding:4px 12px;border-radius:999px;font-size:.74rem;font-weight:800;text-transform:uppercase;letter-spacing:.06em;margin-bottom:12px;align-self:flex-start}
.article-card h3{font-size:1.22rem;margin-bottom:10px;line-height:1.35}
.article-card h3 a{color:#2a2340}
.article-card h3 a:hover{color:#ff6b9d;text-decoration:none}
.article-card p{color:#6a5a7a;font-size:.95rem;margin-bottom:18px;flex:1}
.article-card .read-more{color:#ff6b9d;font-weight:800;font-size:.95rem;display:inline-flex;align-items:center;gap:4px}
.article-card .read-more:hover{text-decoration:none;gap:10px;color:#e63d7e}

/* ---------- Content / Article ---------- */
.content-section{padding:80px 0;position:relative}
.content-wrap{max-width:830px;margin:0 auto;background:#fff;border-radius:24px;padding:48px 54px;box-shadow:0 20px 60px rgba(139,92,246,.08);position:relative;z-index:2}
.content-wrap h1{font-size:2.5rem;margin-bottom:16px;letter-spacing:-.02em}
.content-wrap h2{font-size:1.75rem;margin-top:1.8em;padding-top:1em;border-top:1px dashed #ffe0ec}
.content-wrap h2:first-of-type{border-top:none;padding-top:0}
.content-wrap h3{font-size:1.3rem;margin-top:1.5em;color:#4a3f5e}
.content-wrap p{color:#3d3650;font-size:1.05rem;line-height:1.8}
.content-wrap ul,.content-wrap ol{margin-left:1.5em;color:#3d3650}
.content-wrap li{line-height:1.8;margin-bottom:.6em}
.content-wrap strong{color:#2a2340;font-weight:800}
.content-wrap a{color:#ff6b9d;font-weight:700;border-bottom:2px dotted #ff6b9d}
.content-wrap a:hover{color:#e63d7e;text-decoration:none;border-bottom-style:solid}
.article-meta{color:#8b7fa0;font-size:.92rem;margin-bottom:28px;display:flex;gap:14px;flex-wrap:wrap;align-items:center}
.article-meta .cat{background:linear-gradient(135deg,#ff6b9d,#8b5cf6);color:#fff;padding:5px 14px;border-radius:999px;font-size:.78rem;font-weight:800;text-transform:uppercase;letter-spacing:.06em}

/* Breadcrumb */
.breadcrumb{font-size:.9rem;color:#8b7fa0;margin-bottom:20px}
.breadcrumb a{color:#8b7fa0;border-bottom:none;font-weight:600}
.breadcrumb a:hover{color:#ff6b9d}
.breadcrumb .sep{margin:0 8px;color:#d0bfff}

/* Internal link callout */
.home-link-callout{
  background:linear-gradient(135deg,#fff0f6,#f0e9ff,#e0f2ff);
  border:2px dashed #ffb3d1;border-radius:16px;padding:22px 26px;margin:36px 0 0;
}
.home-link-callout p{margin-bottom:8px;font-weight:800;color:#2a2340}
.home-link-callout a{color:#ff6b9d;font-weight:800;border-bottom:none}

/* ---------- CTA Band ---------- */
.cta-band{
  background:linear-gradient(135deg,#ff6b9d 0%,#8b5cf6 50%,#8ecae6 100%);
  color:#fff;padding:70px 0;text-align:center;position:relative;overflow:hidden;
}
.cta-band::before{content:'';position:absolute;top:-50%;left:-10%;width:400px;height:400px;background:radial-gradient(circle,rgba(255,255,255,.2),transparent 70%);border-radius:50%}
.cta-band::after{content:'';position:absolute;bottom:-50%;right:-10%;width:500px;height:500px;background:radial-gradient(circle,rgba(255,255,255,.15),transparent 70%);border-radius:50%}
.cta-band h2{color:#fff;font-size:2.3rem;margin-bottom:16px;position:relative;z-index:2}
.cta-band p{color:rgba(255,255,255,.95);font-size:1.15rem;margin-bottom:32px;max-width:640px;margin-left:auto;margin-right:auto;position:relative;z-index:2}
.cta-band .hero-ctas{position:relative;z-index:2}
.cta-band .btn-secondary{background:#fff;color:#ff6b9d}
.cta-band .btn-secondary:hover{background:#2a2340;color:#fff}
.cta-band .btn-outline{background:transparent;color:#fff;border-color:#fff}
.cta-band .btn-outline:hover{background:#fff;color:#ff6b9d;border-color:#fff}

/* ---------- Footer ---------- */
.site-footer{background:linear-gradient(135deg,#2a2340 0%,#3d3650 100%);color:#c9c0dc;padding:60px 0 28px;position:relative}
.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr;gap:48px;margin-bottom:40px}
.footer-col h4{color:#fff;font-size:1rem;margin-bottom:18px;text-transform:uppercase;letter-spacing:.06em;font-weight:800}
.footer-col ul{list-style:none;margin:0;padding:0}
.footer-col li{margin-bottom:10px}
.footer-col a{color:#c9c0dc;font-size:.95rem;font-weight:600}
.footer-col a:hover{color:#ff6b9d;text-decoration:none}
.footer-col p{font-size:.95rem;line-height:1.7;color:#a898c0}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding-top:22px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:.9rem;color:#8c7fa5}
.footer-bottom a{color:#a898c0;font-weight:600}

/* ---------- 404 ---------- */
.error-404{text-align:center;padding:110px 0}
.error-404 h1{font-size:7rem;background:linear-gradient(135deg,#ff6b9d,#8b5cf6);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:0;font-weight:900}
.error-404 h2{font-size:1.9rem;margin-bottom:14px}
.error-404 p{color:#6a5a7a;margin-bottom:32px}

/* ---------- Responsive ---------- */
@media (max-width:960px){
  .hero-grid{grid-template-columns:1fr;gap:40px}
  .hero-art{height:320px;max-width:360px;margin:0 auto}
  .hero h1{font-size:2.4rem}
}
@media (max-width:720px){
  .section{padding:56px 0}
  .section-header h2{font-size:1.85rem}
  .footer-grid{grid-template-columns:1fr;gap:30px}
  .header-inner{gap:12px}
  .main-nav ul{flex-wrap:wrap;justify-content:flex-end}
  .content-wrap{padding:30px 24px;border-radius:18px}
  .content-wrap h1{font-size:1.9rem}
  .content-wrap h2{font-size:1.45rem}
  .cta-band h2{font-size:1.7rem}
  .hero{padding:60px 0}
  .hero h1{font-size:2rem}
}
@media (max-width:480px){
  .hero h1{font-size:1.75rem}
  .hero-sub{font-size:1rem}
  .btn{padding:13px 22px;font-size:.95rem}
  .site-title{font-size:1.15rem}
  .site-tagline{display:none}
  .dropdown-menu{right:auto;left:0}
  .hero-art .shopper{width:200px;height:200px;font-size:5rem}
}