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

:root {
  --primary: #2c3e50;
  --primary-light: #34495e;
  --accent: #3498db;
  --accent-hover: #2980b9;
  --gold: #f39c12;
  --gold-hover: #e67e22;
  --bg: #f5f6fa;
  --surface: #ffffff;
  --border: #e0e3e8;
  --text: #2c3e50;
  --text-secondary: #7f8c8d;
  --text-light: #bdc3c7;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-hover: 0 6px 24px rgba(0,0,0,0.12);
  --radius: 10px;
  --transition: 0.25s ease;
  --max-width: 1260px;
  --header-h: 64px;
}

html{scroll-behavior:smooth;font-size:16px}
body{font-family:"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;min-height:100vh}

/* ===== Utility ===== */
.container{max-width:var(--max-width);margin:0 auto;padding:0 20px}
a{color:var(--accent);text-decoration:none;transition:color var(--transition)}
a:hover{color:var(--accent-hover)}
img{max-width:100%;height:auto}

/* ===== Header ===== */
.site-header{background:var(--surface);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100;height:var(--header-h);display:flex;align-items:center}
.site-header .container{display:flex;align-items:center;justify-content:space-between;width:100%}
.logo{display:flex;align-items:center;gap:10px;font-size:1.3rem;font-weight:700;color:var(--primary);white-space:nowrap}
.logo-icon{width:34px;height:34px;background:linear-gradient(135deg,var(--accent),var(--accent-hover));border-radius:8px;display:flex;align-items:center;justify-content:center;color:#fff;font-size:1.1rem}
.nav-links{display:flex;align-items:center;gap:24px;list-style:none}
.nav-links a{color:var(--text-secondary);font-weight:500;font-size:0.95rem;transition:color var(--transition)}
.nav-links a:hover,.nav-links a.active{color:var(--accent)}
.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:6px}
.nav-toggle span{display:block;width:24px;height:2px;background:var(--text);margin:5px 0;transition:var(--transition)}

/* ===== Search ===== */
.search-bar{position:relative;width:280px}
.search-bar input{width:100%;padding:9px 40px 9px 16px;border:1.5px solid var(--border);border-radius:24px;font-size:0.9rem;outline:none;background:var(--bg);transition:var(--transition)}
.search-bar input:focus{border-color:var(--accent);background:var(--surface)}
.search-bar .search-icon{position:absolute;right:14px;top:50%;transform:translateY(-50%);color:var(--text-light);pointer-events:none}

/* ===== Hero ===== */
.hero{padding:48px 0 36px;text-align:center}
.hero h1{font-size:2.2rem;color:var(--primary);margin-bottom:8px}
.hero p{color:var(--text-secondary);font-size:1.05rem;max-width:600px;margin:0 auto}
.hero .badge{display:inline-block;background:linear-gradient(135deg,#f39c12,#f1c40f);color:#fff;padding:4px 14px;border-radius:20px;font-size:0.8rem;font-weight:600;margin-bottom:12px}

/* ===== Category Tabs ===== */
.cat-nav{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:28px;justify-content:center}
.cat-btn{padding:8px 20px;border-radius:20px;border:1.5px solid var(--border);background:var(--surface);color:var(--text-secondary);cursor:pointer;font-size:0.9rem;font-weight:500;transition:var(--transition);white-space:nowrap}
.cat-btn:hover,.cat-btn.active{background:var(--accent);border-color:var(--accent);color:#fff}

/* ===== Ad Slots ===== */
.ad-slot{background:var(--surface);border:1px dashed var(--border);border-radius:var(--radius);display:flex;align-items:center;justify-content:center;color:var(--text-light);font-size:0.85rem;min-height:90px;transition:var(--transition)}
.ad-slot:hover{border-color:var(--accent);color:var(--text-secondary)}
.ad-top{margin-bottom:24px;min-height:80px}
.ad-sidebar{min-height:250px;margin-bottom:20px}
.ad-bottom{margin-top:40px;min-height:100px}

/* ===== Tool Cards Grid ===== */
.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:20px;margin-bottom:32px}
.tool-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:24px;transition:var(--transition);display:flex;flex-direction:column;gap:10px;position:relative;overflow:hidden}
.tool-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-hover);border-color:var(--accent)}
.tool-card.premium::after{content:"PRO";position:absolute;top:12px;right:12px;background:linear-gradient(135deg,var(--gold),var(--gold-hover));color:#fff;font-size:0.7rem;font-weight:700;padding:3px 10px;border-radius:12px}
.tool-icon{width:44px;height:44px;border-radius:10px;display:flex;align-items:center;justify-content:center;font-size:1.4rem;flex-shrink:0}
.tool-icon.blue{background:#eaf2fd;color:var(--accent)}
.tool-icon.green{background:#e8f8f0;color:#27ae60}
.tool-icon.orange{background:#fef5e7;color:#f39c12}
.tool-icon.purple{background:#f3eefb;color:#8e44ad}
.tool-icon.red{background:#fdecea;color:#e74c3c}
.tool-icon.teal{background:#e8f6f8;color:#1abc9c}
.tool-icon.indigo{background:#eef1fb;color:#5b6abf}
.tool-card h3{font-size:1.05rem;color:var(--primary)}
.tool-card p{font-size:0.88rem;color:var(--text-secondary);line-height:1.5;flex:1}
.tool-card .tool-meta{display:flex;align-items:center;gap:8px;font-size:0.78rem;color:var(--text-light)}
.tool-card .tool-meta .free{color:#27ae60;font-weight:600}
.tool-card .tool-meta .pro-badge{color:var(--gold);font-weight:600}

/* ===== Sidebar Layout ===== */
.with-sidebar{display:grid;grid-template-columns:1fr 300px;gap:28px;align-items:start}

/* ===== Content Page ===== */
.content-page{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:32px;margin-bottom:24px}

/* ===== Footer ===== */
.site-footer{background:var(--surface);border-top:1px solid var(--border);padding:24px 0;text-align:center;color:var(--text-light);font-size:0.85rem;margin-top:48px}
.site-footer a{color:var(--text-secondary)}
.site-footer a:hover{color:var(--accent)}

/* ===== Tool Page Common ===== */
.tool-header{text-align:center;padding:36px 0 24px}
.tool-header h1{font-size:1.8rem;color:var(--primary)}
.tool-header p{color:var(--text-secondary);margin-top:6px}
.tool-workspace{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:28px;margin-bottom:24px}
.control-row{display:flex;gap:12px;flex-wrap:wrap;align-items:center;margin-bottom:16px}
.control-row label{font-weight:600;font-size:0.9rem;color:var(--text);min-width:fit-content}

/* ===== Form Elements ===== */
input[type="text"],input[type="number"],input[type="date"],input[type="datetime-local"],select,textarea{font-family:inherit;font-size:0.9rem;padding:10px 14px;border:1.5px solid var(--border);border-radius:8px;outline:none;background:var(--bg);color:var(--text);transition:var(--transition);width:100%}
input:focus,select:focus,textarea:focus{border-color:var(--accent);background:var(--surface)}
textarea{resize:vertical;min-height:160px;font-family:"SF Mono","Consolas","Monaco","Courier New",monospace;font-size:0.85rem;line-height:1.6}
.btn{display:inline-flex;align-items:center;gap:6px;padding:10px 22px;border-radius:8px;border:none;font-size:0.9rem;font-weight:600;cursor:pointer;transition:var(--transition);white-space:nowrap;font-family:inherit}
.btn-primary{background:var(--accent);color:#fff}
.btn-primary:hover{background:var(--accent-hover)}
.btn-outline{background:transparent;color:var(--accent);border:1.5px solid var(--accent)}
.btn-outline:hover{background:var(--accent);color:#fff}
.btn-gold{background:linear-gradient(135deg,var(--gold),var(--gold-hover));color:#fff}
.btn-gold:hover{opacity:0.9}
.btn-sm{padding:6px 14px;font-size:0.82rem}
.result-box{background:var(--bg);border:1px solid var(--border);border-radius:8px;padding:16px;margin-top:16px;min-height:60px;font-family:"SF Mono","Consolas","Monaco","Courier New",monospace;font-size:0.85rem;white-space:pre-wrap;word-break:break-all;max-height:400px;overflow-y:auto}
.drop-zone{border:2px dashed var(--border);border-radius:var(--radius);padding:40px 20px;text-align:center;transition:var(--transition);cursor:pointer;color:var(--text-secondary)}
.drop-zone:hover,.drop-zone.drag-over{border-color:var(--accent);background:#f0f6fd;color:var(--accent)}
.drop-zone .dz-icon{font-size:2.5rem;margin-bottom:10px}
.drop-zone p{font-size:0.9rem}

/* ===== Premium Modal ===== */
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,0.5);z-index:200;display:flex;align-items:center;justify-content:center;padding:20px}
.modal{background:var(--surface);border-radius:var(--radius);padding:32px;max-width:460px;width:100%;text-align:center;box-shadow:0 20px 50px rgba(0,0,0,0.2)}
.modal h2{font-size:1.4rem;margin-bottom:8px;color:var(--primary)}
.modal p{color:var(--text-secondary);margin-bottom:20px;font-size:0.9rem}
.modal .price{font-size:2rem;font-weight:700;color:var(--gold);margin:12px 0}
.modal .btn-gold{margin-top:12px;width:100%;justify-content:center;padding:12px}
.modal-close{position:absolute;top:12px;right:16px;background:none;border:none;font-size:1.4rem;cursor:pointer;color:var(--text-light)}

/* ===== Toast ===== */
.toast{position:fixed;bottom:30px;left:50%;transform:translateX(-50%);background:var(--primary);color:#fff;padding:12px 28px;border-radius:24px;font-size:0.9rem;z-index:300;animation:toastIn 0.35s ease;box-shadow:0 8px 30px rgba(0,0,0,0.2)}
@keyframes toastIn{from{opacity:0;transform:translateX(-50%) translateY(20px)}to{opacity:1;transform:translateX(-50%) translateY(0)}}

/* ===== About Page ===== */
.about-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:20px;margin-top:24px}
.about-card{background:var(--bg);border-radius:var(--radius);padding:20px;text-align:center}
.about-card .about-icon{font-size:2rem;margin-bottom:10px}
.about-card h4{font-size:1rem;color:var(--primary);margin-bottom:6px}
.about-card p{font-size:0.85rem;color:var(--text-secondary)}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .with-sidebar{grid-template-columns:1fr}
  .ad-sidebar{display:none}
}

@media (max-width: 768px) {
  :root{--header-h:56px}
  .nav-links{display:none;position:absolute;top:var(--header-h);left:0;right:0;background:var(--surface);flex-direction:column;padding:16px;border-bottom:1px solid var(--border);box-shadow:var(--shadow)}
  .nav-links.open{display:flex}
  .nav-toggle{display:block}
  .search-bar{width:100%}
  .hero h1{font-size:1.6rem}
  .tool-grid{grid-template-columns:1fr}
  .tool-workspace{padding:16px}
  .content-page{padding:20px}
  .hero{padding:32px 0 24px}
}

@media (max-width: 480px) {
  .hero h1{font-size:1.35rem}
  .btn{font-size:0.82rem;padding:8px 16px}
  .cat-btn{padding:6px 14px;font-size:0.82rem}
}

/* ===== Print ===== */
@media print{.site-header,.site-footer,.ad-slot,.btn,.nav-links{display:none}}