/* ============================================================
   TheSmartCalculator — Global Stylesheet
   ============================================================ */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --bg:#f8f7f4;
  --surface:#ffffff;
  --surface2:#f0ede6;
  --border:#e2ddd6;
  --text:#1c1a17;
  --muted:#7a7468;
  --accent:#1a56db;
  --accent-light:#e8f0fd;
  --accent2:#dc2626;
  --accent3:#16a34a;
  --accent4:#d97706;
  --shadow:0 1px 3px rgba(0,0,0,0.08),0 4px 16px rgba(0,0,0,0.06);
  --shadow-lg:0 4px 6px rgba(0,0,0,0.07),0 10px 40px rgba(0,0,0,0.1);
  --radius:14px;
}
html{scroll-behavior:smooth}
body{font-family:'Segoe UI',system-ui,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;display:flex;flex-direction:column;font-size:16px;line-height:1.6}

/* HEADER */
header{background:var(--surface);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100;box-shadow:0 1px 8px rgba(0,0,0,0.06)}
.header-inner{max-width:1200px;margin:0 auto;padding:0 24px;height:62px;display:flex;align-items:center;justify-content:space-between;gap:16px}
.logo{font-size:1.45rem;font-weight:800;color:var(--text);text-decoration:none;letter-spacing:-0.5px;white-space:nowrap}
.logo span{color:var(--accent)}
.logo sub{font-size:0.5rem;font-weight:600;color:var(--muted);letter-spacing:0.05em;vertical-align:middle;margin-left:3px}
.header-search{position:relative;flex:1;max-width:340px}
.header-search input{width:100%;padding:9px 16px 9px 38px;border:1.5px solid var(--border);border-radius:50px;background:var(--surface2);font-size:0.875rem;outline:none;transition:all 0.2s;color:var(--text)}
.header-search input:focus{border-color:var(--accent);background:var(--surface);box-shadow:0 0 0 3px rgba(26,86,219,0.1)}
.search-icon{position:absolute;left:12px;top:50%;transform:translateY(-50%);color:var(--muted)}
.search-results{display:none;position:absolute;top:calc(100% + 6px);left:0;right:0;background:var(--surface);border:1px solid var(--border);border-radius:12px;box-shadow:var(--shadow-lg);z-index:200;max-height:320px;overflow-y:auto}
.search-results.open{display:block}
.search-item{padding:10px 14px;cursor:pointer;display:flex;align-items:center;gap:10px;border-bottom:1px solid var(--border);transition:background 0.12s;text-decoration:none;color:var(--text)}
.search-item:last-child{border-bottom:none}
.search-item:hover{background:var(--surface2)}
.si-icon{font-size:1.1rem;width:28px;text-align:center}
.si-name{font-size:0.85rem;font-weight:600}
.si-cat{font-size:0.72rem;color:var(--muted)}
.header-nav{display:flex;gap:4px}
.header-nav a{padding:7px 13px;border-radius:8px;font-size:0.82rem;font-weight:600;color:var(--muted);text-decoration:none;transition:all 0.15s;white-space:nowrap}
.header-nav a:hover,.header-nav a.active{color:var(--accent);background:var(--accent-light)}

/* BREADCRUMB */
.breadcrumb{background:var(--surface);border-bottom:1px solid var(--border);padding:10px 0}
.breadcrumb-inner{max-width:1200px;margin:0 auto;padding:0 24px;font-size:0.78rem;color:var(--muted);display:flex;align-items:center;gap:6px;flex-wrap:wrap}
.breadcrumb a{color:var(--accent);text-decoration:none}
.breadcrumb a:hover{text-decoration:underline}
.breadcrumb .sep{color:var(--border)}

/* MAIN LAYOUT */
.container{max-width:1200px;margin:0 auto;padding:0 24px;width:100%}
.page-layout{display:block;padding:36px 0 60px}
.main-content{min-width:0}
.sidebar{display:none}

/* PAGE HEADER */
.page-hero{background:linear-gradient(135deg,#1a56db,#1e40af);color:#fff;padding:40px 0 36px}
.page-hero-inner{max-width:1200px;margin:0 auto;padding:0 24px}
.page-hero h1{font-size:clamp(1.5rem,3vw,2.2rem);font-weight:800;letter-spacing:-0.5px;margin-bottom:8px}
.page-hero p{font-size:1rem;opacity:0.85;max-width:600px;line-height:1.6}

/* CALCULATOR CARD */
.calc-card-main{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden;margin-bottom:28px}
.calc-card-body{padding:28px}

/* FORM ELEMENTS */
.form-group{margin-bottom:16px}
.form-group label{display:block;font-size:0.75rem;font-weight:700;color:var(--muted);margin-bottom:6px;text-transform:uppercase;letter-spacing:0.05em}
.form-group input,.form-group select,.form-group textarea{width:100%;padding:12px 14px;border:1.5px solid var(--border);border-radius:10px;font-size:0.95rem;background:var(--surface2);color:var(--text);outline:none;transition:all 0.15s;font-family:inherit}
.form-group input:focus,.form-group select:focus{border-color:var(--accent);background:var(--surface);box-shadow:0 0 0 3px rgba(26,86,219,0.08)}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.form-row-3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:14px}
.submit-btn{width:100%;padding:14px;background:var(--accent);color:#fff;border:none;border-radius:10px;font-size:1rem;font-weight:700;cursor:pointer;transition:all 0.15s;font-family:inherit;letter-spacing:0.02em;margin-top:4px}
.submit-btn:hover{background:#1342b0;transform:translateY(-1px);box-shadow:0 4px 12px rgba(26,86,219,0.3)}
.submit-btn:active{transform:translateY(0)}

/* RESULT PANEL */
.result-panel{margin-top:20px;background:var(--surface2);border:1px solid var(--border);border-radius:12px;padding:20px;display:none}
.result-panel.show{display:block}
.result-highlight{background:var(--accent);color:#fff;border-radius:10px;padding:16px 18px;margin-bottom:14px;display:flex;justify-content:space-between;align-items:center}
.rh-label{font-size:0.82rem;opacity:0.85}
.rh-val{font-size:1.4rem;font-weight:800;font-family:monospace}
.result-row{display:flex;justify-content:space-between;align-items:center;padding:7px 0;font-size:0.9rem;border-bottom:1px solid var(--border)}
.result-row:last-child{border-bottom:none}
.result-label{color:var(--muted)}
.result-val{font-weight:700;font-family:monospace}
.rv-blue{color:var(--accent)}
.rv-green{color:var(--accent3)}
.rv-red{color:var(--accent2)}
.rv-orange{color:var(--accent4)}
.divider{border:none;border-top:1px solid var(--border);margin:12px 0}
.info-box{background:var(--accent-light);border:1px solid #bdd0f8;border-radius:8px;padding:12px 14px;font-size:0.82rem;color:#1e40af;margin-top:14px;line-height:1.6}

/* RESULT TOOLBAR */
.result-toolbar{display:flex;gap:10px;margin-top:12px}
.rtb-btn{display:inline-flex;align-items:center;gap:6px;padding:9px 18px;background:var(--surface);border:1.5px solid var(--border);border-radius:8px;font-size:0.82rem;font-weight:600;color:var(--muted);cursor:pointer;transition:all 0.15s;font-family:inherit;white-space:nowrap}
.rtb-btn:hover{border-color:var(--accent);color:var(--accent);background:var(--accent-light)}
.rtb-btn.copied,.rtb-btn.saved{background:var(--accent);border-color:var(--accent);color:#fff}

/* TOAST NOTIFICATION */
.ch-toast{position:fixed;bottom:28px;left:50%;transform:translateX(-50%) translateY(20px);background:#1c1a17;color:#fff;padding:11px 22px;border-radius:50px;font-size:0.85rem;font-weight:600;opacity:0;pointer-events:none;transition:all 0.25s ease;z-index:9999;white-space:nowrap;box-shadow:0 4px 20px rgba(0,0,0,0.25)}
.ch-toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* SCIENTIFIC CALC */
.calc-display{background:#1c1a17;border-radius:12px;padding:18px 16px 14px;margin-bottom:14px;text-align:right}
.calc-display .expr{font-family:monospace;font-size:0.8rem;color:#666;min-height:18px;margin-bottom:4px;word-break:break-all}
.calc-display .result{font-family:monospace;font-size:2.2rem;font-weight:500;color:#fff;word-break:break-all;line-height:1.1}
.btn-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-bottom:4px}
.btn-grid button{padding:16px 8px;border:none;border-radius:10px;font-family:monospace;font-size:0.95rem;font-weight:600;cursor:pointer;transition:all 0.1s;user-select:none}
.btn-grid button:active{transform:scale(0.93)}
.btn-num{background:var(--surface2);color:var(--text)}
.btn-num:hover{background:var(--border)}
.btn-op{background:#dce8fd;color:var(--accent);font-weight:700}
.btn-op:hover{background:#c5d9fb}
.btn-eq{background:var(--accent);color:#fff;font-size:1.1rem}
.btn-eq:hover{background:#1342b0}
.btn-clear{background:#fee2e2;color:var(--accent2);font-weight:700}
.btn-clear:hover{background:#fecaca}
.btn-fn{background:#f3f0ff;color:#7c3aed;font-size:0.72rem}
.btn-fn:hover{background:#ede9fe}
.span2{grid-column:span 2}
.sci-fns{display:grid;grid-template-columns:repeat(5,1fr);gap:6px;margin-bottom:10px}
.sci-fns button{padding:10px 4px;border:none;border-radius:8px;font-family:monospace;font-size:0.72rem;background:#f3f0ff;color:#7c3aed;cursor:pointer;transition:background 0.1s}
.sci-fns button:hover{background:#ede9fe}

/* SEO CONTENT SECTIONS */
.content-section{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:28px;margin-bottom:20px}
.content-section h2{font-size:1.2rem;font-weight:800;margin-bottom:14px;letter-spacing:-0.3px;color:var(--text)}
.content-section h3{font-size:1rem;font-weight:700;margin:18px 0 8px;color:var(--text)}
.content-section p{font-size:0.92rem;color:#3a3730;line-height:1.75;margin-bottom:12px}
.content-section p:last-child{margin-bottom:0}
.content-section ul,.content-section ol{padding-left:20px;margin-bottom:12px}
.content-section li{font-size:0.9rem;color:#3a3730;line-height:1.7;margin-bottom:4px}
.formula-box{background:var(--surface2);border:1px solid var(--border);border-radius:8px;padding:14px 16px;font-family:monospace;font-size:0.9rem;margin:12px 0;color:var(--text);border-left:3px solid var(--accent)}

/* FAQ */
.faq-item{border-bottom:1px solid var(--border);padding:14px 0}
.faq-item:last-child{border-bottom:none}
.faq-q{font-size:0.92rem;font-weight:700;cursor:pointer;display:flex;justify-content:space-between;align-items:center;gap:8px}
.faq-a{font-size:0.88rem;color:var(--muted);line-height:1.7;margin-top:8px;display:none}
.faq-a.open{display:block}
.faq-icon{font-size:0.8rem;color:var(--muted);flex-shrink:0;transition:transform 0.2s}
.faq-icon.open{transform:rotate(180deg)}

/* SIDEBAR WIDGETS */
.sidebar-widget{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden}
.widget-title{padding:14px 18px;font-size:0.82rem;font-weight:700;text-transform:uppercase;letter-spacing:0.05em;color:var(--muted);border-bottom:1px solid var(--border);background:var(--surface2)}
.widget-links a{display:flex;align-items:center;gap:10px;padding:11px 18px;text-decoration:none;color:var(--text);font-size:0.87rem;border-bottom:1px solid var(--border);transition:background 0.12s}
.widget-links a:last-child{border-bottom:none}
.widget-links a:hover{background:var(--surface2);color:var(--accent)}
.widget-links .wl-icon{font-size:1rem;width:24px;text-align:center}

/* AD BANNER */

/* HOMEPAGE */
.hero{background:linear-gradient(135deg,#1a56db 0%,#1e40af 60%,#1d3a8a 100%);color:#fff;padding:56px 0 50px}
.hero-inner{max-width:1200px;margin:0 auto;padding:0 24px;text-align:center}
.hero h1{font-size:clamp(2rem,4vw,3rem);font-weight:800;letter-spacing:-1px;margin-bottom:12px}
.hero p{font-size:1.05rem;opacity:0.85;max-width:520px;margin:0 auto 28px;line-height:1.6}
.hero-stats{display:flex;gap:40px;justify-content:center;flex-wrap:wrap}
.hero-stat .num{font-size:1.8rem;font-weight:800;display:block}
.hero-stat .lbl{font-size:0.72rem;opacity:0.75;text-transform:uppercase;letter-spacing:0.1em}
.hero-search{max-width:500px;margin:0 auto 32px;position:relative}
.hero-search input{width:100%;padding:15px 20px 15px 48px;border:none;border-radius:50px;font-size:1rem;outline:none;color:var(--text);box-shadow:0 4px 20px rgba(0,0,0,0.2)}
.hero-search .hs-icon{position:absolute;left:18px;top:50%;transform:translateY(-50%);font-size:1.1rem}
.hero-search-results{display:none;position:absolute;top:calc(100% + 8px);left:0;right:0;background:var(--surface);border-radius:12px;box-shadow:var(--shadow-lg);z-index:200;max-height:300px;overflow-y:auto;text-align:left}
.hero-search-results.open{display:block}

/* HOMEPAGE SECTIONS */
.home-main{padding:48px 0 60px}
.section-block{margin-bottom:52px}
.section-head{display:flex;align-items:center;gap:14px;margin-bottom:22px;padding-bottom:14px;border-bottom:2px solid var(--border)}
.section-icon{width:44px;height:44px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:1.2rem;flex-shrink:0}
.section-title{font-size:1.3rem;font-weight:800;letter-spacing:-0.3px}
.section-subtitle{font-size:0.82rem;color:var(--muted);margin-top:2px}
.section-link{margin-left:auto;font-size:0.82rem;color:var(--accent);text-decoration:none;font-weight:600;white-space:nowrap}
.section-link:hover{text-decoration:underline}
.calc-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:12px}
.calc-tile{background:var(--surface);border:1.5px solid var(--border);border-radius:12px;padding:18px 16px;text-decoration:none;display:flex;align-items:center;gap:12px;transition:all 0.18s;color:var(--text)}
.calc-tile:hover{border-color:var(--accent);box-shadow:var(--shadow-lg);transform:translateY(-2px);background:var(--accent-light);color:var(--accent)}
.calc-tile .ct-icon{font-size:1.3rem;flex-shrink:0;width:32px;text-align:center}
.calc-tile .ct-name{font-size:0.87rem;font-weight:700;line-height:1.3}


/* BELOW CALCULATOR WIDGETS */
.below-calc-widgets{display:flex;gap:20px;flex-wrap:wrap;margin-top:24px;margin-bottom:8px}
.below-calc-widgets .sidebar-widget{flex:1;min-width:220px;max-width:400px}
.below-calc-widgets .widget-links{display:flex;flex-wrap:wrap}
.below-calc-widgets .widget-links a{flex:1 0 auto;min-width:140px}

/* FOOTER */
footer{background:#1c1a17;color:#e5e7eb;padding:48px 0 24px;margin-top:auto}
.footer-grid{max-width:1200px;margin:0 auto;padding:0 24px;display:grid;grid-template-columns:2fr repeat(4,1fr);gap:40px;margin-bottom:40px}
.footer-brand .logo{color:#fff;font-size:1.3rem}
.footer-brand p{font-size:0.82rem;color:#9ca3af;margin-top:10px;line-height:1.6;max-width:220px}
.footer-col h4{font-size:0.78rem;font-weight:700;text-transform:uppercase;letter-spacing:0.08em;color:#9ca3af;margin-bottom:12px}
.footer-col a{display:block;font-size:0.83rem;color:#9ca3af;text-decoration:none;margin-bottom:7px;transition:color 0.15s}
.footer-col a:hover{color:#fff}
.footer-bottom{max-width:1200px;margin:0 auto;padding:20px 24px 0;border-top:1px solid #374151;display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:12px}
.footer-copy{font-size:0.78rem;color:#6b7280}
.footer-links{display:flex;gap:18px}
.footer-links a{font-size:0.78rem;color:#6b7280;text-decoration:none;transition:color 0.15s}
.footer-links a:hover{color:#fff}

/* RESPONSIVE */
@media(max-width:1024px){
  .page-layout{padding:24px 0}
  .footer-grid{grid-template-columns:1fr 1fr;gap:28px}
}
@media(max-width:768px){
  .header-nav{display:none}
  .header-inner{padding:0 14px;height:50px}
  .logo{font-size:1.1rem}
  .header-search{max-width:none;flex:1}
  .form-row,.form-row-3{grid-template-columns:1fr}
  .calc-grid{grid-template-columns:repeat(auto-fill,minmax(140px,1fr))}
  .footer-grid{grid-template-columns:1fr 1fr}
  .hero{padding:20px 0 24px}
  
  .main-content{padding:16px 14px 32px}
  .calc-card-body{padding:16px 14px}
  .submit-btn{padding:12px;font-size:0.9rem;width:100%}
  .result-panel{padding:12px}
  .result-toolbar{gap:6px;margin-top:10px}
  .rtb-btn{padding:8px 14px;font-size:0.78rem}
  .page-hero{padding:20px 16px 24px}
  .page-hero-inner h1{font-size:1.4rem}
  .breadcrumb{padding:8px 14px;font-size:0.75rem}
  .rh-val{font-size:1.4rem}
}
@media(max-width:480px){
  .header-inner{padding:0 12px;height:46px}
  .logo{font-size:1rem}
  .calc-grid{grid-template-columns:1fr 1fr}
  .footer-grid{grid-template-columns:1fr}
  .hero-stats{gap:12px}
  .calc-card-body{padding:12px}
  .form-group label{font-size:0.8rem;margin-bottom:4px}
  .form-group input,.form-group select{padding:10px 11px;font-size:16px !important}
  .submit-btn{padding:11px;font-size:0.88rem}
  .result-highlight{padding:12px 14px}
  .rh-label{font-size:0.75rem}
  .rh-val{font-size:1.25rem}
  .result-row{padding:5px 0;font-size:0.82rem}
  .result-label{font-size:0.8rem}
  .result-val{font-size:0.82rem}
  .rtb-btn{padding:7px 12px;font-size:0.74rem;gap:4px}
  .page-hero-inner h1{font-size:1.2rem}
  .page-hero-inner p{font-size:0.82rem}
  .content-section h2{font-size:1.1rem}
  .faq-q{font-size:0.88rem}
  .faq-a{font-size:0.82rem}
}
@media(max-width:360px){
  .calc-grid{grid-template-columns:1fr}
  .rtb-btn{font-size:0.7rem;padding:7px 10px}
  .submit-btn{font-size:0.84rem}
}
::-webkit-scrollbar{width:6px}
::-webkit-scrollbar-track{background:var(--surface2)}
::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}