/* ============================================================
   VOLTAGE DROP CALCULATORS — PREMIUM STYLESHEET v2
   Adapted from Chemistry Calculators Design System
   ============================================================ */


/* ── Variables ──────────────────────────────────────────── */
:root {
  --emerald:       #2563eb;
  --emerald-dark:  #1d4ed8;
  --emerald-deep:  #1e3a5f;
  --emerald-light: #dbeafe;
  --emerald-glow:  rgba(37,99,235,.18);
  --teal:          #3b82f6;
  --teal-light:    #eff6ff;
  --mint:          #93c5fd;

  --text:          #111827;
  --text-2:        #374151;
  --text-3:        #525252;
  --text-4:        #737373;

  --bg:            #ffffff;
  --bg-soft:       #f8fafc;
  --bg-muted:      #f0f2f5;
  --border:        #e2e8f0;
  --border-light:  #f1f5f9;

  --success:       #10b981;
  --warning:       #f59e0b;
  --danger:        #ef4444;

  --radius-xl:     24px;
  --radius:        16px;
  --radius-sm:     12px;
  --radius-xs:     8px;
  --shadow-sm:     0 1px 2px rgba(0,0,0,.04);
  --shadow:        0 4px 12px rgba(0,0,0,.03), 0 1px 3px rgba(0,0,0,.04);
  --shadow-lg:     0 20px 40px rgba(0,0,0,.04);
  --shadow-glow:   0 0 0 3px var(--emerald-light);
  --transition:    .22s ease;
  --t-fast:        .14s ease;
  --max-w:         1220px;
}

/* ── Reset ──────────────────────────────────────────────── */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:'Inter',system-ui,-apple-system,sans-serif;
  background:var(--bg-muted);
  color:var(--text);
  line-height:1.7;
  font-size:16px;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:var(--emerald);text-decoration:none;transition:color var(--transition)}
a:hover{color:var(--emerald-dark)}
::selection{background:var(--emerald-light);color:var(--emerald-deep)}

/* ═══════════════════════════════════════════════════════════
   HEADER / MEGA-NAV
   ═══════════════════════════════════════════════════════════ */
.site-header{
  position:sticky;top:0;z-index:200;
  background:#ffffff;
  border-bottom:1px solid var(--border-light);
  transition:box-shadow var(--transition);
}
.site-header.scrolled{box-shadow:0 2px 20px rgba(0,0,0,.07)}

.nav-inner{
  display:flex;align-items:center;justify-content:space-between;
  max-width:var(--max-w);margin:0 auto;
  padding:0 28px;height:62px;
}

/* Logo */
.nav-logo{display:flex;align-items:center;gap:10px;text-decoration:none;}
.nav-logo-icon{
  width:36px;height:36px;
  background:linear-gradient(135deg,var(--emerald),var(--teal));
  border-radius:10px;
  display:flex;align-items:center;justify-content:center;
  font-size:18px;
  box-shadow:0 2px 8px rgba(37,99,235,.25);
}
.nav-logo-text{
  font-size:1.05rem;font-weight:800;color:var(--text);
  letter-spacing:-.4px;
}

/* Nav links row */
.nav-links{
  display:flex;gap:2px;list-style:none;align-items:center;
}
.nav-links li{position:relative}
.nav-links>li>a{
  font-size:.82rem;font-weight:500;color:var(--text-2);
  padding:7px 11px;border-radius:var(--radius-xs);
  transition:all var(--t-fast);white-space:nowrap;
  display:flex;align-items:center;gap:4px;
}
.nav-links>li>a:hover,
.nav-links>li>a.active{
  background:var(--emerald-light);color:var(--emerald-dark);
}

/* Nav socials */
.nav-socials {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-left: 14px;
  margin-left: 14px;
  border-left: 1px solid var(--border);
}
.social-icon {
  color: var(--text-3);
  transition: color var(--t-fast);
  display: flex;
  align-items: center;
}
.social-icon:hover {
  color: var(--emerald);
}

/* Dropdown trigger arrow */
.nav-links .has-drop>a::after{
  content:'';display:inline-block;width:0;height:0;
  border-left:4px solid transparent;border-right:4px solid transparent;
  border-top:4px solid currentColor;margin-left:2px;
  transition:transform var(--t-fast);
}
.nav-links .has-drop:hover>a::after{transform:rotate(180deg)}

/* Dropdown mega panel */
.nav-drop{
  display:none;position:absolute;top:100%;left:50%;
  transform:translateX(-50%);
  min-width:480px;
  background:#fff;border:1px solid var(--border);
  border-radius:var(--radius);
  box-shadow:var(--shadow-lg);
  padding:16px;
  z-index:300;
}
.nav-links .has-drop:hover .nav-drop{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:4px;
  animation:fadeDown .18s ease;
}
.nav-drop a{
  display:flex;align-items:center;gap:10px;
  padding:10px 12px;border-radius:var(--radius-sm);
  color:var(--text-2);font-size:.86rem;font-weight:500;
  transition:all var(--t-fast);
}
.nav-drop a:hover{background:var(--emerald-light);color:var(--emerald-dark);}
.nav-drop-icon{
  width:32px;height:32px;border-radius:8px;
  background:var(--bg-muted);
  display:flex;align-items:center;justify-content:center;
  font-size:16px;flex-shrink:0;
  transition:background var(--t-fast);
}
.nav-drop a:hover .nav-drop-icon{background:var(--emerald-light);}

/* Hamburger */
.nav-toggle{
  display:none;flex-direction:column;gap:5px;
  background:none;border:none;cursor:pointer;padding:6px;
}
.nav-toggle span{
  display:block;width:22px;height:2px;
  background:var(--text);border-radius:2px;
  transition:all var(--transition);
}

@keyframes fadeDown{
  from{opacity:0;transform:translateX(-50%) translateY(-6px)}
  to{opacity:1;transform:translateX(-50%) translateY(0)}
}

/* ═══════════════════════════════════════════════════════════
   PAGE HERO (calculator pages)
   ═══════════════════════════════════════════════════════════ */
.page-hero{
  padding:48px 28px 0;
  max-width:var(--max-w);margin:0 auto;
}
.page-hero h1{
  font-size:clamp(1.8rem,4.5vw,2.6rem);
  font-weight:900;letter-spacing:-.6px;
  color:var(--text);line-height:1.15;
  margin-bottom:10px;
}
.page-hero h1 .kw{color:var(--emerald)} /* coloured keyword */
.page-hero p{
  font-size:1.05rem;color:var(--text-3);
  max-width:600px;line-height:1.6;
}
.page-hero.center-hero{text-align:center}
.page-hero.center-hero p{margin:0 auto;max-width:750px}

/* ═══════════════════════════════════════════════════════════
   MAIN WRAPPER
   ═══════════════════════════════════════════════════════════ */
.main-wrapper{
  max-width:var(--max-w);margin:0 auto;
  padding:32px 28px 60px;
}

/* ═══════════════════════════════════════════════════════════
   TWO-COLUMN LAYOUT
   ═══════════════════════════════════════════════════════════ */
.calc-layout{
  display:grid;
  grid-template-columns:1fr 400px;
  gap:36px;align-items:start;
}
.content-col{min-width:0}
.sticky-card{position:sticky;top:80px}

/* ═══════════════════════════════════════════════════════════
   CALCULATOR CARD — CLEAN DESIGN
   ═══════════════════════════════════════════════════════════ */
.calc-card{
  background:#ffffff;
  border:1px solid var(--border);
  border-radius:var(--radius-xl);
  padding:32px 28px;
  box-shadow:var(--shadow-lg);
  position:relative;
  overflow:hidden;
}
.calc-card-title{
  font-size:1.1rem;font-weight:800;color:var(--text);
  margin-bottom:24px;
  display:flex;align-items:center;gap:10px;
}
.calc-card-title span{font-size:1.3rem}

/* Form fields */
.field-group{margin-bottom:18px}
.field-group label{
  display:block;font-size:.7rem;font-weight:700;
  color:var(--text-3);margin-bottom:6px;
  text-transform:uppercase;letter-spacing:1px;
}
.field-group input,
.field-group select{
  width:100%;padding:12px 14px;
  border:1.5px solid var(--border);
  border-radius:var(--radius-sm);
  font-size:.95rem;font-family:inherit;
  color:var(--text);background:var(--bg);
  transition:border-color var(--t-fast),box-shadow var(--t-fast);
  outline:none;
  -webkit-appearance:none;
  appearance:none;
}
.field-group select{
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%236b7280'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 16px;
  padding-right: 36px;
  cursor:pointer;
}
.input-with-unit {
  display: flex;
  align-items: stretch;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  transition: border-color var(--t-fast), box-shadow var(--t-fast);
  overflow: hidden;
}
.input-with-unit:focus-within {
  border-color: var(--emerald);
  box-shadow: var(--shadow-glow);
}
.input-with-unit input {
  border: none;
  border-radius: 0;
  box-shadow: none;
  flex: 1;
}
.input-with-unit input:focus {
  border-color: transparent;
  box-shadow: none;
}
.input-with-unit select {
  border: none;
  border-radius: 0;
  box-shadow: none;
  background: var(--bg-soft);
  color: var(--emerald);
  font-weight: 600;
  width: auto;
  border-left: 1.5px solid var(--border);
  padding: 12px 14px;
  cursor: pointer;
  background-image: none;
}
.input-with-unit select:focus {
  border-color: transparent;
  box-shadow: none;
  outline: none;
}

.field-group input:focus,
.field-group select:focus{
  border-color:var(--emerald);
  box-shadow:0 0 0 3px var(--emerald-glow);
}
.field-hint{font-size:.74rem;color:var(--text-4);margin-top:4px}

/* Calculate button */
.btn-calc{
  width:100%;padding:16px;
  background:var(--emerald);
  color:#fff;border:none;
  border-radius:var(--radius-sm);
  font-size:1.05rem;font-weight:800;font-family:inherit;
  cursor:pointer;letter-spacing:.5px;
  transition:all var(--t-fast);
  margin-top:10px;
}
.btn-calc:hover{
  background:var(--emerald-dark);
  box-shadow:var(--shadow-lg);
  transform:translateY(-1px);
}
.btn-calc:active{transform:translateY(0)}

/* Result box */
.result-box{
  margin-top:24px;
  background:var(--bg-soft);
  border:1.5px solid var(--emerald-light);
  border-radius:var(--radius-sm);
  padding:24px;display:none;
}
.result-box.show{display:block;animation:slideUp .3s ease}
.result-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px}
.result-label{
  font-size:.75rem;font-weight:700;
  color:var(--emerald-dark);
  text-transform:uppercase;letter-spacing:1px;
}
.result-value{
  font-size:2.2rem;font-weight:900;color:var(--text);
  margin:4px 0 2px;letter-spacing:-.5px;
  font-family:'JetBrains Mono','Courier New',monospace;
}

/* Realtime result area */
.realtime-results{
  margin-top:24px;
  background:var(--bg-soft);
  border:1.5px solid var(--emerald-light);
  border-radius:var(--radius-sm);
  padding:24px;
}
.rt-row{
  display:flex;justify-content:space-between;align-items:baseline;
  padding:10px 0;
  border-bottom:1px solid var(--border-light);
}
.rt-row:last-child{border-bottom:none}
.rt-label{
  font-size:.75rem;font-weight:700;
  color:var(--text-3);
  text-transform:uppercase;letter-spacing:1px;
}
.rt-value{
  font-size:1.6rem;font-weight:900;
  color:var(--text);
  font-family:'JetBrains Mono','Courier New',monospace;
  letter-spacing:-.5px;
}
.rt-value.success{color:var(--success)}
.rt-value.warning{color:var(--warning)}
.rt-value.danger{color:var(--danger)}
.rt-value.primary{color:var(--emerald)}
.rt-sub{
  font-size:.78rem;font-weight:600;
  margin-top:2px;text-align:right;
}

/* Omni-Style Action Buttons */
.calc-actions {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 12px;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--border-light);
}
.action-stack {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.action-btn {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  padding: 8px 12px;
  font-size: .85rem;
  font-weight: 600;
  color: var(--text-2);
  cursor: pointer;
  transition: border-color var(--t-fast), color var(--t-fast);
  font-family:inherit;
}
.action-btn:hover {
  border-color: var(--emerald);
  color: var(--emerald-dark);
}
.share-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 16px 8px;
}
.share-icon {
  background: var(--emerald);
  color: white;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 10px var(--emerald-glow);
}

/* Feedback Box */
.calc-feedback {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--border-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: .8rem;
  color: var(--text-3);
}
.feedback-btns { display: flex; gap: 8px; }
.fb-btn {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 10px;
  font-size: .8rem;
  cursor: pointer;
  color: var(--text-2);
  font-family:inherit;
}
.fb-btn:hover { border-color: var(--emerald); color: var(--emerald); }

/* ═══════════════════════════════════════════════════════════
   CONTENT SECTIONS
   ═══════════════════════════════════════════════════════════ */
.content-section{margin-bottom:40px}
.content-section h2{
  font-size:1.3rem;font-weight:800;
  color:var(--text);margin-bottom:14px;
  padding-bottom:10px;
  border-bottom:2px solid var(--emerald-light);
  display:flex;align-items:center;gap:8px;
}
.content-section p{color:var(--text-2);margin-bottom:12px}
.content-section ul,.content-section ol{
  color:var(--text-2);padding-left:22px;
}
.content-section li{margin-bottom:7px}
.content-section strong{color:var(--text)}

/* Data Table */
.table-responsive{overflow-x:auto;margin:16px 0}
.data-table{
  width:100%;border-collapse:collapse;
  font-size:.88rem;
}
.data-table th{
  background:var(--emerald-light);
  color:var(--emerald-dark);
  font-weight:700;text-align:left;
  padding:10px 14px;font-size:.75rem;
  text-transform:uppercase;letter-spacing:.5px;
  border-bottom:2px solid var(--emerald);
}
.data-table td{
  padding:10px 14px;
  border-bottom:1px solid var(--border-light);
  color:var(--text-2);
}
.data-table tbody tr:hover{background:var(--bg-soft)}
.data-table td:nth-child(3),
.data-table td:nth-child(4),
.data-table th:nth-child(3),
.data-table th:nth-child(4){
  text-align:right;font-family:'JetBrains Mono','Courier New',monospace;
}

/* Tips list */
.tips-list{list-style:none;padding:0}
.tips-list li{
  padding:10px 14px 10px 40px;
  position:relative;
  margin-bottom:8px;
  background:var(--bg-soft);
  border-radius:var(--radius-xs);
  color:var(--text-2);
  font-size:.9rem;
}
.tips-list li::before{
  content:'💡';position:absolute;left:12px;top:10px;
}

/* Formula badge */
.formula-badge{
  background:var(--bg-soft);
  border:1.5px solid var(--emerald);
  border-radius:var(--radius-sm);
  padding:18px 22px;
  font-family:'JetBrains Mono','Courier New',monospace;
  font-size:1.1rem;font-weight:700;
  color:var(--emerald-deep);
  margin:14px 0 20px;
  position:relative;
}
.formula-badge::before{
  content:'FORMULA';position:absolute;
  top:-9px;left:16px;
  background:var(--bg);padding:0 8px;
  font-size:.65rem;font-weight:700;
  color:var(--emerald);letter-spacing:1px;
  font-family:'Inter',sans-serif;
}

/* Steps list */
.steps-list{list-style:none;padding:0;counter-reset:steps}
.steps-list li{
  counter-increment:steps;
  padding:12px 16px 12px 52px;position:relative;
  background:var(--bg-soft);
  border:1px solid var(--border-light);
  border-radius:var(--radius-sm);
  margin-bottom:8px;color:var(--text-2);
  transition:border-color var(--t-fast);
}
.steps-list li:hover{border-color:var(--emerald-light)}
.steps-list li::before{
  content:counter(steps);
  position:absolute;left:14px;top:50%;transform:translateY(-50%);
  width:26px;height:26px;
  background:var(--emerald);color:#fff;
  border-radius:50%;display:flex;align-items:center;justify-content:center;
  font-size:.78rem;font-weight:700;
}

/* Example box */
.example-box{
  background:var(--bg);
  border:1px solid var(--border);
  border-radius:var(--radius);padding:26px 28px;
  box-shadow:var(--shadow-sm);
}
.example-box .ex-step{
  display:flex;gap:10px;margin-bottom:8px;
  font-size:.92rem;color:var(--text-2);
}
.ex-label{font-weight:700;color:var(--emerald);min-width:72px}

/* FAQ */
.faq-item{
  border:1px solid var(--border-light);
  border-radius:var(--radius-sm);
  margin-bottom:8px;overflow:hidden;
  transition:border-color var(--t-fast);
}
.faq-item:hover{border-color:var(--emerald-light)}
.faq-question{
  font-weight:600;color:var(--text);
  cursor:pointer;padding:16px 18px;
  display:flex;justify-content:space-between;align-items:center;
  gap:12px;user-select:none;font-size:.95rem;
}
.faq-question::after{
  content:'›';font-size:1.3rem;color:var(--emerald);
  transition:transform var(--transition);flex-shrink:0;
  font-weight:300;
}
.faq-item.open .faq-question::after{transform:rotate(90deg)}
.faq-answer{
  display:none;color:var(--text-2);
  padding:0 18px 16px;font-size:.9rem;line-height:1.7;
}
.faq-item.open .faq-answer{display:block;animation:slideUp .2s ease}
.faq-item.open{border-color:var(--emerald-light);background:var(--bg-soft)}

/* ═══════════════════════════════════════════════════════════
   "OTHER CALCULATORS" GRID (on homepage)
   ═══════════════════════════════════════════════════════════ */
.other-calcs{
  margin-top:48px;padding-top:40px;
  border-top:2px solid var(--border-light);
}
.other-calcs-title{
  font-size:1.4rem;font-weight:800;color:var(--text);
  margin-bottom:4px;
}
.other-calcs-sub{color:var(--text-3);margin-bottom:24px;font-size:.95rem}

.calc-grid{
  display:grid;
  grid-template-columns:repeat(2,1fr);
  gap:16px;
}
.calc-grid-card{
  background:var(--bg);
  border:1.5px solid var(--border);
  border-radius:var(--radius);
  padding:22px 20px;
  transition:all var(--transition);
  text-decoration:none;color:var(--text);
  display:flex;align-items:flex-start;gap:14px;
  position:relative;overflow:hidden;
}
.calc-grid-card::before{
  content:'';position:absolute;bottom:0;left:0;right:0;
  height:3px;
  background:linear-gradient(90deg,var(--emerald),var(--teal));
  transform:scaleX(0);transform-origin:left;
  transition:transform var(--transition);
}
.calc-grid-card:hover{
  border-color:var(--emerald);
  box-shadow:0 4px 20px rgba(37,99,235,.1);
  transform:translateY(-3px);
}
.calc-grid-card:hover::before{transform:scaleX(1)}
.cgc-icon{
  width:44px;height:44px;
  background:var(--emerald-light);
  border-radius:12px;
  display:flex;align-items:center;justify-content:center;
  font-size:20px;flex-shrink:0;
  transition:background var(--t-fast);
}
.calc-grid-card:hover .cgc-icon{background:var(--emerald);color:#fff}
.cgc-body{min-width:0}
.cgc-title{font-size:.9rem;font-weight:700;color:var(--text);margin-bottom:3px}
.cgc-desc{font-size:.8rem;color:var(--text-3);line-height:1.45}
.cgc-arrow{
  position:absolute;top:18px;right:16px;
  color:var(--emerald);opacity:0;font-size:1rem;
  transition:all var(--t-fast);
}
.calc-grid-card:hover .cgc-arrow{opacity:1;transform:translateX(3px)}

/* ═══════════════════════════════════════════════════════════
   RELATED CALCULATORS (on sub-pages)
   ═══════════════════════════════════════════════════════════ */
.related-grid{
  display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));
  gap:12px;margin-top:14px;
}
.related-card{
  display:flex;align-items:center;gap:12px;
  background:var(--bg);border:1px solid var(--border);
  border-radius:var(--radius-sm);padding:14px 16px;
  transition:all var(--transition);text-decoration:none;color:var(--text);
}
.related-card:hover{
  border-color:var(--emerald);
  box-shadow:0 4px 16px rgba(37,99,235,.1);
  transform:translateY(-2px);color:var(--emerald-dark);
}
.related-icon{
  width:36px;height:36px;border-radius:var(--radius-sm);
  background:var(--emerald-light);
  display:flex;align-items:center;justify-content:center;
  font-size:17px;flex-shrink:0;
}
.related-text{font-size:.87rem;font-weight:600}

/* ═══════════════════════════════════════════════════════════
   BREADCRUMB
   ═══════════════════════════════════════════════════════════ */
.breadcrumb{
  font-size:.82rem;color:var(--text-4);
  margin-bottom:20px;display:flex;align-items:center;gap:6px;flex-wrap:wrap;
}
.breadcrumb a{color:var(--text-4)}
.breadcrumb a:hover{color:var(--emerald)}
.breadcrumb .sep{color:var(--border)}
.breadcrumb .current{color:var(--emerald);font-weight:500}

/* ═══════════════════════════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════════════════════════ */
.site-footer{
  background:#111827;color:#9ca3af;
  padding:52px 28px 28px;margin-top:64px;
}
.footer-inner{
  max-width:var(--max-w);margin:0 auto;
  display:grid;grid-template-columns:2fr 1fr 1fr;gap:44px;
}
.footer-brand p{font-size:.87rem;margin-top:12px;line-height:1.7;color:#6b7280}
.footer-col h4{
  font-size:.82rem;font-weight:700;color:#e5e7eb;
  margin-bottom:14px;letter-spacing:.5px;text-transform:uppercase;
}
.footer-col ul{list-style:none}
.footer-col li{margin-bottom:8px}
.footer-col a{color:#6b7280;font-size:.85rem;transition:color var(--t-fast)}
.footer-col a:hover{color:var(--mint)}
.footer-bottom{
  max-width:var(--max-w);margin:36px auto 0;
  padding-top:20px;border-top:1px solid #1f2937;
  display:flex;justify-content:space-between;align-items:center;
  flex-wrap:wrap;gap:10px;font-size:.8rem;color:#4b5563;
}
.footer-socials{display:flex;align-items:center;gap:16px}
.footer-socials .social-icon{color:#6b7280;transition:color var(--t-fast)}
.footer-socials .social-icon:hover{color:var(--mint)}
.footer-bottom-links{display:flex;gap:16px}
.footer-bottom-links a{color:#4b5563;font-size:.8rem}
.footer-bottom-links a:hover{color:var(--mint)}

/* ═══════════════════════════════════════════════════════════
   ANIMATIONS
   ═══════════════════════════════════════════════════════════ */
@keyframes slideUp{
  from{opacity:0;transform:translateY(10px)}
  to{opacity:1;transform:translateY(0)}
}
@keyframes fadeIn{
  from{opacity:0}
  to{opacity:1}
}
@keyframes pulseGlow{
  0%,100%{box-shadow:0 0 20px rgba(37,99,235,.15)}
  50%{box-shadow:0 0 35px rgba(37,99,235,.3)}
}

/* ═══════════════════════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════════════════════ */
@media(max-width:1024px){
  .calc-grid{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:900px){
  .calc-layout{grid-template-columns:1fr}
  .sidebar-col{order:-1}
  .sticky-card{position:static}
  .footer-inner{grid-template-columns:1fr 1fr}
}
@media(max-width:640px){
  .nav-links{
    display:none;position:absolute;
    top:62px;left:0;right:0;
    background:rgba(255,255,255,.97);
    backdrop-filter:blur(12px);
    -webkit-backdrop-filter:blur(12px);
    padding:12px 20px 20px;
    border-bottom:1px solid var(--border);
    flex-direction:column;gap:2px;
  }
  .nav-links.open{display:flex}
  .nav-links .has-drop .nav-drop{
    display:none;position:static;transform:none;
    min-width:0;border:none;box-shadow:none;
    padding:4px 0 4px 18px;
    grid-template-columns:1fr;
  }
  .nav-links.open .has-drop:hover .nav-drop,
  .nav-links.open .has-drop.open-mobile .nav-drop{
    display:grid;animation:none;
  }
  .nav-toggle{display:flex}
  .footer-inner{grid-template-columns:1fr}
  .footer-bottom{flex-direction:column;text-align:center}
  .calc-grid{grid-template-columns:1fr}
  .related-grid{grid-template-columns:1fr}
  .page-hero h1{font-size:1.6rem}
  .nav-socials{
    padding-left:0;margin-left:0;border-left:none;
    border-top:1px solid var(--border);
    padding-top:14px;margin-top:8px;
    justify-content:center;
  }
}

/* ═══════════════════════════════════════════════════════════
   CLEAN DASHBOARD UI (OVERHAUL)
   ═══════════════════════════════════════════════════════════ */
.calc-dashboard {
  margin-top: 24px;
  background: var(--bg-soft);
  border: 1.5px solid var(--emerald-light);
  border-radius: var(--radius-sm);
  padding: 24px;
}

.dashboard-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}

.dashboard-results {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  flex: 1;
}

.dashboard-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.dashboard-label {
  font-size: .65rem;
  font-weight: 700;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.8px;
}

.dashboard-value {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text);
  font-family: 'JetBrains Mono', monospace;
}

.dashboard-value.primary { color: var(--emerald); }
.dashboard-value.success { color: var(--success); }
.dashboard-value.warning { color: var(--warning); }
.dashboard-value.danger { color: var(--danger); }

.dashboard-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: 20px;
  border-left: 1px solid var(--border-light);
}

.dash-action-btn {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  padding: 8px 12px;
  font-size: .75rem;
  font-weight: 700;
  color: var(--text-2);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--t-fast);
  white-space: nowrap;
  font-family: inherit;
}

.dash-action-btn:hover {
  border-color: var(--emerald);
  color: var(--emerald);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.dash-action-btn svg {
  flex-shrink: 0;
}

.dashboard-status {
  grid-column: span 3;
  font-size: .78rem;
  font-weight: 600;
  margin-top: 4px;
  padding-top: 8px;
  border-top: 1px solid var(--border-light);
}

/* Mobile dashboard */
@media (max-width: 768px) {
  .dashboard-header {
    flex-direction: column;
    align-items: stretch;
  }
  .dashboard-results {
    grid-template-columns: 1fr;
    gap: 12px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-light);
  }
  .dashboard-actions {
    padding-left: 0;
    border-left: none;
    padding-top: 16px;
    justify-content: center;
  }
  .dashboard-status {
    grid-column: span 1;
  }
}

/* ═══════════════════════════════════════════════════════════
   PREMIUM SEO GUIDE SECTION — DARK NAVY & ORANGE
   ═══════════════════════════════════════════════════════════ */
:root {
    --seo-navy-bg: #061b2f;
    --seo-navy-card: #08233d;
    --seo-navy-border: #0b3157;
    --seo-orange: #ff7a00;
    --seo-orange-glow: rgba(255, 122, 0, 0.2);
    --seo-glass: rgba(255, 255, 255, 0.03);
    --seo-glass-border: rgba(255, 255, 255, 0.08);
}

.seo-guide-section {
    background-color: var(--seo-navy-bg);
    color: #f9fafb;
    padding: 90px 24px;
    font-family: 'Inter', sans-serif;
    line-height: 1.7;
}

.seo-container {
    max-width: 1180px;
    margin: 0 auto;
}

/* Section 1: Intro */
.seo-intro {
    text-align: center;
    margin-bottom: 60px;
}
.seo-eyebrow {
    font-size: 0.75rem;
    font-weight: 800;
    color: var(--seo-orange);
    text-transform: uppercase;
    letter-spacing: 2px;
    display: inline-block;
    position: relative;
    margin-bottom: 15px;
    padding: 0 40px;
}
.seo-eyebrow::before, .seo-eyebrow::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 30px;
    height: 2px;
    background: var(--seo-orange);
}
.seo-eyebrow::before { left: 0; }
.seo-eyebrow::after { right: 0; }

.seo-intro h2 {
    font-size: clamp(2rem, 5vw, 3.2rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 20px;
    letter-spacing: -1.5px;
}
.seo-intro p {
    color: #9ca3af;
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto;
}

/* Section 2: Feature Panel */
.seo-feature-panel {
    background: var(--seo-glass);
    backdrop-filter: blur(12px);
    border: 1px solid var(--seo-glass-border);
    border-radius: 24px;
    padding: 50px;
    margin-bottom: 40px;
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 40px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.3);
    position: relative;
    overflow: hidden;
}
.seo-feature-panel::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, var(--seo-orange-glow), transparent 70%);
    z-index: -1;
}

.seo-feature-panel h3 {
    font-size: 1.8rem;
    font-weight: 800;
    margin-bottom: 20px;
    color: white;
}
.seo-feature-panel p {
    font-size: 1rem;
    color: #9ca3af;
    margin-bottom: 20px;
}

.feature-list {
    list-style: none;
    padding: 0;
}
.feature-list li {
    padding: 12px 0;
    border-bottom: 1px solid var(--seo-glass-border);
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 0.95rem;
    color: #e5e7eb;
}
.feature-list li i {
    color: var(--seo-orange);
    font-size: 1.2rem;
}

/* Section 3: Problem Grid */
.problem-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}
.problem-card {
    background: var(--seo-navy-card);
    border: 1px solid var(--seo-navy-border);
    border-radius: 24px;
    padding: 30px;
    transition: 0.3s ease;
}
.problem-card:hover {
    transform: translateY(-5px);
    border-color: var(--seo-orange);
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}
.problem-card i {
    font-size: 1.8rem;
    color: var(--seo-orange);
    margin-bottom: 20px;
    display: block;
}
.problem-card h4 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 12px;
}
.problem-card p {
    font-size: 0.88rem;
    color: #9ca3af;
    line-height: 1.6;
}

/* Section 4: Safety Grid */
.safety-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 40px;
}
.safety-card {
    background: var(--seo-navy-card);
    border: 1px solid var(--seo-navy-border);
    border-radius: 24px;
    padding: 40px;
}
.warning-card {
    background: #0a111a;
    border: 2px solid var(--seo-orange);
    box-shadow: 0 0 20px var(--seo-orange-glow);
}

/* Section 5: Timeline */
.repair-timeline {
    margin: 60px 0;
    display: flex;
    justify-content: space-between;
    position: relative;
    gap: 20px;
}
.repair-timeline::before {
    content: '';
    position: absolute;
    top: 25px;
    left: 40px;
    right: 40px;
    height: 2px;
    background: var(--seo-navy-border);
    z-index: 0;
}
.timeline-step {
    flex: 1;
    text-align: center;
    position: relative;
    z-index: 1;
}
.step-dot {
    width: 50px;
    height: 50px;
    background: var(--seo-orange);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    margin: 0 auto 20px;
    box-shadow: 0 0 15px var(--seo-orange-glow);
    border: 4px solid var(--seo-navy-bg);
}
.timeline-step h5 {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 8px;
}
.timeline-step p {
    font-size: 0.8rem;
    color: #9ca3af;
}

/* Section 6: Info Grid */
.seo-info-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 40px;
}
.info-panel {
    background: var(--seo-glass);
    border: 1px solid var(--seo-glass-border);
    border-radius: 24px;
    padding: 40px;
}

/* Section 7: CTA Band */
.seo-final-cta {
    background: linear-gradient(90deg, #0b3157 0%, #061b2f 100%);
    border: 1px solid var(--seo-glass-border);
    border-radius: 24px;
    padding: 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 40px;
}
.cta-text h4 { font-size: 1.5rem; font-weight: 800; margin-bottom: 8px; }
.cta-text p { color: #9ca3af; }

.cta-btns {
    display: flex;
    gap: 15px;
}
.btn-premium {
    padding: 14px 28px;
    border-radius: 12px;
    font-weight: 700;
    text-decoration: none;
    transition: 0.3s;
}
.btn-orange {
    background: var(--seo-orange);
    color: white;
    box-shadow: 0 5px 15px var(--seo-orange-glow);
}
.btn-orange:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--seo-orange-glow);
}
.btn-outline {
    border: 1px solid var(--seo-glass-border);
    color: white;
}
.btn-outline:hover {
    background: var(--seo-glass);
}

@media (max-width: 850px) {
    .seo-guide-section { padding: 55px 20px; }
    .seo-feature-panel, .safety-grid, .seo-info-grid, .seo-final-cta {
        grid-template-columns: 1fr;
        padding: 30px;
    }
    .repair-timeline {
        flex-direction: column;
        gap: 30px;
    }
    .repair-timeline::before { display: none; }
    .timeline-step { text-align: left; display: flex; gap: 20px; align-items: center; }
    .step-dot { margin: 0; flex-shrink: 0; }
}