/* ============================================================
   TO WATTS — Redesigned Stylesheet (Mobile-Responsive, 3D & Dials)
   Premium SaaS Power Conversion Calculator
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800;900&family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&display=swap');

/* ── TOKENS ─────────────────────────────────────────────── */
:root {
  --orange-main:       #FF6B35;
  --orange-hover:      #E0531F;
  --orange-light:      #FFF0EB;
  --orange-glow:       rgba(255, 107, 53, 0.25);
  
  --dark-solid:        #0F121F;
  --dark-solid-hover:  #161925;
  --dark-charcoal:     #1E1E24;
  
  --white:             #FFFFFF;
  --light-gray:        #F8F9FA;
  --light-gray-2:      #F1F3F5;
  --border-light:      #E9ECEF;
  
  --text-dark:         #12141D;
  --text-dark-muted:   #5C627A;
  --text-light:        #FFFFFF;
  --text-light-muted:  #FFD5C6;
  
  --success:           #00B884;
  --warning:           #F59F00;
  
  --radius-sm:         8px;
  --radius-md:         12px;
  --radius-lg:         18px;
  --radius-xl:         24px;
  
  --shadow-sm:         0 2px 8px rgba(0, 0, 0, 0.05);
  --shadow-md:         0 8px 24px rgba(0, 0, 0, 0.08);
  --shadow-lg:         0 16px 40px rgba(0, 0, 0, 0.12);
  --transition:        0.25s cubic-bezier(0.4, 0, 0.2, 1);
  
  --font-heading:      'Outfit', sans-serif;
  --font-body:         'Plus Jakarta Sans', sans-serif;
  
  /* Animation tuning custom variables */
  --flow-speed:        2s;
  --pulse-speed:       1.5s;
}

/* ── RESET ──────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background: var(--light-gray);
  color: var(--text-dark);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--orange-main); text-decoration: none; transition: all var(--transition); }
a:hover { color: var(--orange-hover); }
img { max-width: 100%; display: block; }
ul { list-style: none; }
button { font-family: var(--font-body); cursor: pointer; border: none; outline: none; }
input, select, textarea { font-family: var(--font-body); outline: none; }

/* ── SCROLLBAR ──────────────────────────────────────────── */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--light-gray); }
::-webkit-scrollbar-thumb { background: var(--orange-main); border-radius: 4px; }

/* ── TYPOGRAPHY ─────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-dark);
  letter-spacing: -0.02em;
}
h1 { font-size: clamp(2rem, 5vw, 3.5rem); font-weight: 800; }
h2 { font-size: clamp(1.5rem, 4vw, 2.5rem); font-weight: 800; }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.7rem); font-weight: 700; }
h4 { font-size: 1.15rem; font-weight: 600; }
p { color: var(--text-dark-muted); line-height: 1.75; }

.gradient-text {
  background: linear-gradient(135deg, var(--text-dark) 30%, var(--orange-main) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ── HEADER / NAV ───────────────────────────────────────── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: 80px;
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  transition: all var(--transition);
}
.site-header.scrolled {
  box-shadow: var(--shadow-sm);
  background: var(--white);
  height: 70px;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 24px;
}
.logo-link img {
  height: 56px;
  width: auto;
  transition: height var(--transition);
}
.site-header.scrolled .logo-link img {
  height: 46px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}
.nav-links a {
  color: var(--text-dark-muted);
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  transition: all var(--transition);
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--text-dark);
  background: var(--light-gray-2);
}
.nav-cta {
  background: var(--dark-solid) !important;
  color: var(--white) !important;
  padding: 10px 22px !important;
}
.nav-cta:hover {
  background: var(--orange-main) !important;
  box-shadow: var(--orange-glow);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  padding: 6px;
  cursor: pointer;
  z-index: 101;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-dark);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ── LAYOUTS ────────────────────────────────────────────── */
.page-content { padding-top: 80px; }
.container {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 24px;
}
.section { padding: 80px 0; }
.section-sm { padding: 48px 0; }

/* ── SPLIT PANEL CALCULATOR SYSTEM ───────────────────────── */
.split-layout {
  display: grid;
  grid-template-columns: 46% 54%;
  min-height: calc(100vh - 80px);
  background: var(--white);
  border-bottom: 1px solid var(--border-light);
}

/* ── LEFT PANEL (ORANGE) ────────────────────────────────── */
.panel-left {
  background: linear-gradient(145deg, #FF7B47 0%, #FF5216 100%);
  color: var(--white);
  padding: 60px 48px;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  position: relative;
  overflow: hidden;
}
.panel-left::before {
  content: '';
  position: absolute;
  top: -10%; left: -10%;
  width: 120%; height: 120%;
  background: radial-gradient(circle at 10% 10%, rgba(255, 255, 255, 0.15) 0%, transparent 60%);
  pointer-events: none;
}
.panel-left h1, .panel-left h2, .panel-left h3 {
  color: var(--white);
}

.calc-container {
  max-width: 520px;
  width: 100%;
  margin-top: 24px;
  margin-left: auto;
  margin-right: auto;
}

/* Tab Selector Styles (Solid Dark Charcoal Block) */
.toggle-group {
  display: flex;
  background: rgba(0, 0, 0, 0.15);
  padding: 5px;
  border-radius: var(--radius-md);
  margin-bottom: 32px;
  gap: 4px;
  border: 1px solid rgba(255, 255, 255, 0.1);
}
.toggle-btn {
  flex: 1;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  background: transparent;
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: all var(--transition);
  white-space: nowrap;
}
.toggle-btn:hover {
  color: var(--white);
  background: rgba(255, 255, 255, 0.05);
}
.toggle-btn.active {
  background: var(--dark-solid);
  color: var(--white);
  box-shadow: var(--shadow-sm);
}

/* Input Fields & Form styling in Orange Panel */
.form-group {
  margin-bottom: 24px;
  position: relative;
}
.form-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-light-muted);
  margin-bottom: 8px;
}
.form-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}
.form-input {
  width: 100%;
  padding: 16px 20px;
  background: rgba(255, 255, 255, 0.15);
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-md);
  color: var(--white);
  font-size: 1.15rem;
  font-weight: 600;
  transition: all var(--transition);
}
.form-input::placeholder {
  color: rgba(255, 255, 255, 0.5);
}
.form-input:focus {
  background: rgba(255, 255, 255, 0.25);
  border-color: var(--white);
  box-shadow: 0 0 0 4px rgba(255, 255, 255, 0.15);
}
.form-unit {
  position: absolute;
  right: 20px;
  font-weight: 800;
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.7);
  text-transform: uppercase;
  pointer-events: none;
}

/* Custom Select drop-down in Orange Panel */
.form-select {
  width: 100%;
  padding: 16px 20px;
  background: rgba(255, 255, 255, 0.15) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%23ffffff' stroke-width='2.5'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E") no-repeat right 20px center;
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-md);
  color: var(--white);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  appearance: none;
  transition: all var(--transition);
}
.form-select:focus {
  background-color: rgba(255, 255, 255, 0.25);
  border-color: var(--white);
}
.form-select option {
  background: #E0531F;
  color: var(--white);
  font-weight: 600;
}

/* Custom Sliders */
.slider-container {
  margin-top: 12px;
  margin-bottom: 24px;
}
.slider-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-light-muted);
  text-transform: uppercase;
  margin-top: 6px;
}
.custom-range {
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.3);
  border-radius: 3px;
  outline: none;
  appearance: none;
  cursor: pointer;
}
.custom-range::-webkit-slider-thumb {
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--dark-solid);
  border: 2px solid var(--white);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition);
}
.custom-range::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

/* Calculator action buttons */
.btn-calc-row {
  display: flex;
  gap: 12px;
  margin-top: 32px;
}
.btn-calculate {
  flex: 2;
  padding: 16px 28px;
  background: var(--dark-solid);
  color: var(--white);
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: all var(--transition);
}
.btn-calculate:hover {
  background: #000;
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
}
.btn-calculate:active { transform: translateY(0); }

.btn-clear {
  flex: 1;
  padding: 16px 20px;
  background: rgba(255, 255, 255, 0.15);
  color: var(--white);
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: all var(--transition);
}
.btn-clear:hover {
  background: rgba(255, 255, 255, 0.25);
  border-color: var(--white);
}

/* ── RIGHT PANEL (WHITE) ────────────────────────────────── */
.panel-right {
  background: var(--white);
  color: var(--text-dark);
  padding: 60px 48px;
  display: flex;
  flex-direction: column;
}

.panel-right-section {
  max-width: 620px;
  width: 100%;
  margin-left: auto;
  margin-right: auto;
}

.result-outer {
  border-bottom: 1.5px solid var(--border-light);
  padding-bottom: 36px;
  margin-bottom: 36px;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  align-items: flex-start;
}

.result-title {
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--orange-main);
  margin-bottom: 12px;
}

.result-main {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
  min-height: 80px;
}

.result-number {
  font-family: var(--font-heading);
  font-size: clamp(2.8rem, 6vw, 4.8rem);
  font-weight: 900;
  color: var(--text-dark);
  line-height: 1;
}

.result-large-unit {
  font-family: var(--font-heading);
  font-size: clamp(1.4rem, 3vw, 2.2rem);
  font-weight: 800;
  color: var(--text-dark-muted);
}

.result-details {
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--text-dark-muted);
  margin-bottom: 20px;
  word-break: break-all;
}

.btn-actions-row {
  display: flex;
  gap: 12px;
}
.btn-action-outline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  color: var(--text-dark);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: all var(--transition);
}
.btn-action-outline:hover {
  background: var(--light-gray-2);
  border-color: var(--text-dark-muted);
}
.btn-action-outline.copied {
  background: var(--success);
  color: var(--white);
  border-color: var(--success);
}

/* ── DYNAMIC FLOW VISUALIZER ────────────────────────────── */
.flow-visualizer-box {
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 36px;
}
.flow-visualizer-box h4 {
  font-size: 0.9rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dark-muted);
  margin-bottom: 12px;
}
.flow-graphic-container {
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex;
  justify-content: center;
  align-items: center;
}

@keyframes flowLine {
  to {
    stroke-dashoffset: -40;
  }
}
.flow-path-animated {
  stroke-dasharray: 8, 8;
  animation: flowLine var(--flow-speed, 2s) linear infinite;
}

@keyframes pulseGlow {
  0%, 100% {
    filter: drop-shadow(0 0 2px var(--orange-main));
    opacity: 0.7;
  }
  50% {
    filter: drop-shadow(0 0 10px var(--orange-main));
    opacity: 1;
  }
}
.load-glow-animated {
  animation: pulseGlow var(--pulse-speed, 1.5s) ease-in-out infinite;
}

/* ── 3D ISOMETRIC POWER SIMULATOR ────────────────────────── */
.scene-3d {
  perspective: 1200px;
  width: 100%;
  height: 480px;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  position: relative;
}
.board-3d {
  width: 340px;
  height: 340px;
  transform: rotateX(60deg) rotateZ(-45deg);
  transform-style: preserve-3d;
  position: relative;
  background: #F1F3F5;
  border: 5px solid var(--dark-charcoal);
  border-radius: var(--radius-md);
  box-shadow: 15px 15px 40px rgba(0, 0, 0, 0.18);
  background-image: 
    linear-gradient(rgba(0,0,0,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,0,0,0.05) 1px, transparent 1px);
  background-size: 20px 20px;
}

.wire-3d {
  position: absolute;
  background: rgba(18, 20, 29, 0.1);
  height: 4px;
  transform-style: preserve-3d;
}
.wire-3d.active {
  background: var(--orange-main);
  box-shadow: 0 0 8px var(--orange-main);
}
.wire-flow-particle {
  position: absolute;
  width: 6px;
  height: 6px;
  background: #FF9E79;
  border-radius: 50%;
  transform: translateZ(2px);
  box-shadow: 0 0 6px #FFF;
  display: none;
}
.wire-3d.active .wire-flow-particle {
  display: block;
}

/* 3D Cube Object */
.cube-3d {
  position: absolute;
  width: var(--w, 40px);
  height: var(--h, 40px);
  transform-style: preserve-3d;
  transform: translate3d(var(--x), var(--y), 0);
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.cube-face {
  position: absolute;
  width: 100%;
  height: 100%;
  background: #E9ECEF;
  border: 1px solid #CED4DA;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-weight: 800;
  color: var(--text-dark-muted);
}
.cube-top {
  height: var(--h, 40px);
  transform: translateZ(var(--z, 30px));
  background: var(--white);
  border: 1.5px solid var(--dark-charcoal);
  color: var(--text-dark);
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px;
}
.cube-top svg {
  width: 75%;
  height: 75%;
  fill: none;
  stroke: var(--dark-charcoal);
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition: stroke 0.3s ease;
}
.cube-front {
  transform: rotateX(-90deg);
  transform-origin: bottom;
  background: #DEE2E6;
  height: var(--z, 30px);
  margin-top: calc(var(--h, 40px) - var(--z, 30px));
}
.cube-side {
  transform: rotateY(90deg);
  transform-origin: right;
  background: #CED4DA;
  width: var(--z, 30px);
  margin-left: calc(var(--w, 40px) - var(--z, 30px));
}

/* Active 3D Cube Glow State */
.cube-3d.active .cube-top {
  background: var(--orange-main);
  border-color: var(--orange-hover);
  box-shadow: 0 0 15px rgba(255, 107, 53, 0.6);
}
.cube-3d.active .cube-top svg {
  stroke: var(--white);
}
.cube-3d.active .cube-front {
  background: var(--orange-hover);
}
.cube-3d.active .cube-side {
  background: #C44315;
}

/* 3D Breaker Dashboard Switches */
.breaker-panel {
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 16px;
  margin-top: 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.breaker-switch {
  width: 50px;
  height: 26px;
  background: var(--success);
  border-radius: 13px;
  position: relative;
  cursor: pointer;
  transition: all var(--transition);
}
.breaker-switch::after {
  content: '';
  position: absolute;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--white);
  top: 2px;
  left: 26px;
  transition: all var(--transition);
  box-shadow: var(--shadow-sm);
}
.breaker-switch.tripped {
  background: var(--orange-hover);
}
.breaker-switch.tripped::after {
  left: 2px;
}

/* ── CHARTS & SCHEMATICS ───────────────────────────────── */
.chart-box {
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 36px;
  position: relative;
}
.chart-box h4 {
  font-size: 0.9rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dark-muted);
  margin-bottom: 18px;
}
.chart-container-wrapper {
  position: relative;
  height: 280px;
  width: 100%;
}

.diagram-box {
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 36px;
}
.diagram-box h4 {
  font-size: 0.9rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dark-muted);
  margin-bottom: 16px;
}
.diagram-graphic {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
  background: var(--white);
  border: 1px dashed var(--border-light);
  border-radius: var(--radius-md);
  margin-top: 10px;
}

/* ── HOMEPAGE HERO (Light Elegant style with Orange features) ── */
.home-hero {
  background: radial-gradient(circle at 80% 20%, rgba(255, 107, 53, 0.08) 0%, transparent 60%), var(--white);
  padding: 100px 0 80px;
  border-bottom: 1px solid var(--border-light);
  position: relative;
}
.home-hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--orange-light);
  border: 1px solid rgba(255, 107, 53, 0.2);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--orange-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 24px;
}
.home-hero-badge .dot {
  width: 6px; height: 6px;
  background: var(--orange-main);
  border-radius: 50%;
}
.home-hero h1 {
  margin-bottom: 20px;
  line-height: 1.15;
}
.home-hero p {
  font-size: 1.15rem;
  color: var(--text-dark-muted);
  max-width: 600px;
  margin-bottom: 36px;
}
.home-hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* Hero section grid and media styles */
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

@media (max-width: 991px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 48px;
    text-align: center;
  }
  .home-hero p {
    margin-left: auto;
    margin-right: auto;
  }
  .home-hero-actions {
    justify-content: center;
  }
  .hero-media {
    margin-top: 24px;
  }
}

/* Animations for floating elements */
@keyframes float-drift-1 {
  0% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-8px) rotate(1deg); }
  100% { transform: translateY(0px) rotate(0deg); }
}

@keyframes float-drift-2 {
  0% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(8px) rotate(-1.5deg); }
  100% { transform: translateY(0px) rotate(0deg); }
}

@keyframes float-drift-3 {
  0% { transform: translate(0, 0); }
  50% { transform: translate(-6px, -4px); }
  100% { transform: translate(0, 0); }
}

@keyframes float-drift-4 {
  0% { transform: translate(0, 0); }
  50% { transform: translate(6px, 4px); }
  100% { transform: translate(0, 0); }
}

@keyframes glow-pulse {
  0% { opacity: 0.6; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.2); }
  100% { opacity: 0.6; transform: scale(1); }
}

.float-anim-1 {
  animation: float-drift-1 5s ease-in-out infinite;
}

.float-anim-2 {
  animation: float-drift-2 6s ease-in-out infinite;
}

.float-anim-3 {
  animation: float-drift-3 4.5s ease-in-out infinite;
}

.float-anim-4 {
  animation: float-drift-4 5.5s ease-in-out infinite;
}

.pulse-dot {
  animation: glow-pulse 2s ease-in-out infinite;
}

.notebook-wrap:hover {
  transform: translateY(-5px) scale(1.02);
}


/* Homepage grid of converters */
.home-tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
  gap: 24px;
  margin-top: 48px;
}
.home-tool-card {
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}
.home-tool-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--orange-main);
  opacity: 0;
  transition: opacity var(--transition);
}
.home-tool-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(255, 107, 53, 0.2);
}
.home-tool-card:hover::before {
  opacity: 1;
}
.home-tool-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: var(--orange-light);
  color: var(--orange-main);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin-bottom: 24px;
  transition: all var(--transition);
}
.home-tool-card:hover .home-tool-icon {
  background: var(--orange-main);
  color: var(--white);
}
.home-tool-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
}
.home-tool-card p {
  font-size: 0.9rem;
  margin-bottom: 24px;
  flex: 1;
}
.home-tool-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--border-light);
  padding-top: 16px;
}
.home-tool-tag {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--orange-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.home-tool-arrow {
  color: var(--text-dark-muted);
  font-size: 1.1rem;
  transition: transform var(--transition);
}
.home-tool-card:hover .home-tool-arrow {
  transform: translateX(4px);
  color: var(--orange-main);
}

/* ── DYNAMIC INFO & FORMULA STRIPS ──────────────────────── */
.formula-strip-light {
  padding: 16px 20px;
  background: var(--light-gray);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  font-family: 'Courier New', Courier, monospace;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--orange-main);
  margin-bottom: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}
.formula-strip-light span {
  color: var(--text-dark-muted);
  font-family: var(--font-body);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Breadcrumb nav */
.light-breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.light-breadcrumb a {
  color: var(--text-dark-muted);
}
.light-breadcrumb a:hover {
  color: var(--text-dark);
}
.light-breadcrumb span.sep {
  color: var(--border-light);
  font-weight: 400;
}
.light-breadcrumb span.current {
  color: var(--orange-main);
}

/* ── FAQ ACCORDION (Light clean style) ──────────────────── */
.light-faq-section {
  background: var(--light-gray);
  border-top: 1px solid var(--border-light);
  padding: 80px 0;
}
.faq-container-light {
  max-width: 800px;
  margin: 0 auto;
}
.faq-item-light {
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition);
}
.faq-item-light.open {
  border-color: rgba(255, 107, 53, 0.3);
  box-shadow: var(--shadow-md);
}
.faq-trigger-light {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 24px;
  background: none;
  text-align: left;
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-dark);
  gap: 12px;
}
.faq-trigger-light:hover {
  color: var(--orange-main);
}
.faq-icon-light {
  font-size: 1.2rem;
  color: var(--text-dark-muted);
  transition: transform var(--transition);
  flex-shrink: 0;
}
.faq-item-light.open .faq-icon-light {
  transform: rotate(45deg);
  color: var(--orange-main);
}
.faq-content-light {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out;
}
.faq-content-inner-light {
  padding: 0 24px 20px;
  color: var(--text-dark-muted);
  font-size: 0.92rem;
  line-height: 1.7;
}
.faq-item-light.open .faq-content-light {
  max-height: 350px;
}

/* ── SIDEBAR & NAVIGATION (Light clean) ─────────────────── */
.sidebar-light {
  display: flex;
  flex-direction: column;
  gap: 24px;
}
.sidebar-card-light {
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
}
.sidebar-card-light h4 {
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dark-muted);
  margin-bottom: 16px;
  border-bottom: 1.5px solid var(--border-light);
  padding-bottom: 12px;
}

.sidebar-nav-links {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.sidebar-nav-links a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  color: var(--text-dark-muted);
  font-size: 0.9rem;
  font-weight: 600;
}
.sidebar-nav-links a:hover {
  background: var(--light-gray);
  color: var(--text-dark);
}
.sidebar-nav-links a.active {
  background: var(--orange-light);
  color: var(--orange-main);
}

/* ── STATS BAR (Light style) ────────────────────────────── */
.stats-bar-light {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  margin-bottom: 40px;
}
.stat-item-light {
  padding: 28px;
  text-align: center;
  border-right: 1px solid var(--border-light);
}
.stat-item-light:last-child {
  border-right: none;
}
.stat-value-light {
  font-family: var(--font-heading);
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--text-dark);
  line-height: 1.1;
  margin-bottom: 4px;
}
.stat-label-light {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-dark-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ── FOOTER (Clean light gray style) ─────────────────────── */
.site-footer-light {
  background: var(--white);
  border-top: 1px solid var(--border-light);
  padding: 64px 0 32px;
}
.footer-grid-light {
  display: grid;
  grid-template-columns: 280px 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 32px;
}
.footer-brand-light p {
  font-size: 0.9rem;
  color: var(--text-dark-muted);
  margin-top: 16px;
}
.footer-logo-light {
  height: 54px;
  width: auto;
}
.footer-col-light h5 {
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dark);
  margin-bottom: 18px;
}
.footer-col-light ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-col-light ul a {
  font-size: 0.88rem;
  color: var(--text-dark-muted);
  font-weight: 500;
}
.footer-col-light ul a:hover {
  color: var(--orange-main);
}
.footer-bottom-light {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}
.footer-bottom-light p {
  font-size: 0.82rem;
  color: var(--text-dark-muted);
}

/* ── BUTTONS & GENERAL UTILITIES ────────────────────────── */
.btn-primary-orange {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  background: var(--orange-main);
  color: var(--white);
  border-radius: var(--radius-md);
  font-size: 0.92rem;
  font-weight: 700;
  box-shadow: var(--orange-glow);
  transition: all var(--transition);
}
.btn-primary-orange:hover {
  background: var(--orange-hover);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255, 107, 53, 0.35);
}
.btn-primary-orange:active { transform: translateY(0); }

.btn-secondary-dark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  background: var(--dark-solid);
  color: var(--white);
  border-radius: var(--radius-md);
  font-size: 0.92rem;
  font-weight: 700;
  transition: all var(--transition);
}
.btn-secondary-dark:hover {
  background: #000;
  color: var(--white);
  transform: translateY(-2px);
}
.btn-secondary-dark:active { transform: translateY(0); }

.btn-outline-dark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  background: transparent;
  border: 2px solid var(--text-dark);
  border-radius: var(--radius-md);
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-dark);
  transition: all var(--transition);
}
.btn-outline-dark:hover {
  background: var(--text-dark);
  color: var(--white);
  transform: translateY(-2px);
}

/* ── REFERENCE TABLES (Clean light gray grid) ───────────── */
.table-container-light {
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  background: var(--white);
}
.table-header-light {
  padding: 24px;
  border-bottom: 1px solid var(--border-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.table-header-light h3 {
  font-size: 1.15rem;
}
.table-light {
  width: 100%;
  border-collapse: collapse;
}
.table-light th {
  background: var(--light-gray);
  padding: 14px 20px;
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-dark-muted);
  text-align: left;
  border-bottom: 1.5px solid var(--border-light);
}
.table-light td {
  padding: 14px 20px;
  font-size: 0.9rem;
  color: var(--text-dark-muted);
  border-bottom: 1px solid var(--border-light);
}
.table-light tr:last-child td {
  border-bottom: none;
}
.table-light tbody tr:hover td {
  background: var(--light-gray);
  color: var(--text-dark);
}

/* Info Alert box in white panel */
.info-alert-light {
  display: flex;
  gap: 12px;
  padding: 18px 20px;
  background: var(--orange-light);
  border: 1.5px solid rgba(255, 107, 53, 0.25);
  border-radius: var(--radius-md);
  margin-bottom: 24px;
}
.info-alert-light i {
  color: var(--orange-main);
  font-size: 1.25rem;
  flex-shrink: 0;
}
.info-alert-light p {
  font-size: 0.88rem;
  color: var(--text-dark-muted);
}

/* ── MOBILE RESPONSIVENESS OVERHAUL ────────────────────── */
.mobile-nav-light {
  display: none;
  position: fixed;
  top: 80px;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  padding: 16px 24px;
  z-index: 99;
  flex-direction: column;
  gap: 4px;
  max-height: calc(100vh - 80px);
  overflow-y: auto;
}
.mobile-nav-light.open {
  display: flex;
}
.mobile-nav-light a {
  padding: 12px 16px;
  color: var(--text-dark-muted);
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
}
.mobile-nav-light a:hover {
  background: var(--light-gray);
  color: var(--text-dark);
}

@media (max-width: 1024px) {
  .split-layout {
    grid-template-columns: 1fr;
  }
  .panel-left {
    padding: 48px 24px;
  }
  .panel-right {
    padding: 48px 24px;
  }
  .footer-grid-light {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .site-header {
    height: 70px;
  }
  .mobile-nav-light {
    top: 70px;
  }
  .nav-links { display: none; }
  .nav-toggle { display: flex; }
  .stats-bar-light {
    grid-template-columns: 1fr 1fr;
  }
  .stat-item-light {
    border-right: none;
    border-bottom: 1px solid var(--border-light);
  }
  .stat-item-light:nth-child(2n) {
    border-right: none;
  }
  .footer-grid-light {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .home-hero {
    padding: 80px 0 60px;
  }
}

@media (max-width: 480px) {
  .stats-bar-light {
    grid-template-columns: 1fr;
  }
  .stat-item-light {
    border-bottom: 1px solid var(--border-light);
  }
  .stat-item-light:last-child {
    border-bottom: none;
  }
  .btn-calc-row {
    flex-direction: column;
    gap: 8px;
  }
  .btn-actions-row {
    flex-direction: column;
    gap: 8px;
  }
  .btn-action-outline {
    width: 100%;
    justify-content: center;
  }
  .toggle-group {
    flex-direction: column;
    gap: 2px;
  }
}

/* ============================================================
   ARTICLE & BLOG LAYOUT SYSTEM
   ============================================================ */
.article-grid {
  display: grid;
  grid-template-columns: 2.1fr 1fr;
  gap: 40px;
  margin-top: 40px;
}
@media (max-width: 991px) {
  .article-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}

.article-card {
  padding: 40px;
  border-radius: var(--radius-lg);
  background: var(--white);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
  margin-bottom: 32px;
  transition: box-shadow var(--transition);
}
.article-card:hover {
  box-shadow: var(--shadow-md);
}

.post-content h2 {
  font-size: 1.65rem;
  margin-top: 36px;
  margin-bottom: 18px;
  color: var(--text-dark);
  border-left: 4px solid var(--orange-main);
  padding-left: 14px;
  line-height: 1.3;
}
.post-content h3 {
  font-size: 1.3rem;
  margin-top: 28px;
  margin-bottom: 12px;
  color: var(--text-dark);
  line-height: 1.4;
}
.post-content p {
  margin-bottom: 22px;
  font-size: 0.98rem;
  line-height: 1.8;
  color: var(--text-dark-muted);
}
.post-content ul, .post-content ol {
  margin-left: 24px;
  margin-bottom: 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.post-content li {
  font-size: 0.96rem;
  color: var(--text-dark-muted);
  line-height: 1.7;
}
.post-content li strong {
  color: var(--text-dark);
}

.post-content .formula-block {
  background: var(--orange-light);
  border-left: 4px solid var(--orange-main);
  padding: 16px 20px;
  border-radius: var(--radius-md);
  font-family: 'Courier New', Courier, monospace;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--orange-main);
  margin: 24px 0;
  display: inline-block;
}

.post-content .ref-table {
  width: 100%;
  border-collapse: collapse;
  margin: 28px 0;
  font-size: 0.92rem;
}
.post-content .ref-table th {
  background: var(--light-gray);
  color: var(--text-dark);
  font-weight: 700;
  padding: 14px 16px;
  border-bottom: 2px solid var(--border-light);
  text-align: left;
}
.post-content .ref-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-dark-muted);
}
.post-content .ref-table tr:hover {
  background: var(--light-gray-2);
}

.post-content .info-alert-light, .post-content .warning-alert {
  margin: 28px 0 !important;
  border-radius: var(--radius-md);
}

.post-content img.article-image {
  width: 100%;
  border-radius: var(--radius-md);
  margin: 24px 0;
  box-shadow: var(--shadow-sm);
}

.post-content .icon-wrap {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--orange-light);
  color: var(--orange-main);
  margin-right: 12px;
  font-size: 1.2rem;
}

/* Pagination container */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin-top: 48px;
}
.pagination-btn {
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  background: var(--white);
  color: var(--text-dark-muted);
  border: 1px solid var(--border-light);
  font-weight: 600;
  font-size: 0.9rem;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}
.pagination-btn:hover:not(.disabled) {
  background: var(--orange-light);
  color: var(--orange-main);
  border-color: rgba(255, 107, 53, 0.25);
  cursor: pointer;
}
.pagination-btn.active {
  background: var(--orange-main);
  color: var(--white);
  border-color: var(--orange-main);
}
.pagination-btn.disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ============================================================
   MEGA MENU NAVIGATION
   ============================================================ */
.nav-dropdown {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center;
}
.nav-dropdown-trigger {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  font-weight: 600;
  color: var(--text-dark-muted);
}
.nav-dropdown:hover .nav-dropdown-trigger {
  color: var(--orange-main);
}
.mega-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(15px);
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: 28px;
  min-width: 920px;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 1000;
  margin-top: 12px;
}
.mega-menu::before {
  content: '';
  position: absolute;
  top: -15px;
  left: 0;
  width: 100%;
  height: 15px;
  background: transparent;
}
.nav-dropdown:hover .mega-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
.mega-menu-inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
}
.mega-menu-col h6 {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--orange-main);
  margin-bottom: 12px;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 6px;
}
.mega-menu-col a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-dark-muted);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}
.mega-menu-col a i {
  font-size: 1.15rem;
  color: var(--text-dark-muted);
  transition: color var(--transition);
}
.mega-menu-col a:hover {
  background: var(--orange-light);
  color: var(--orange-main);
}
.mega-menu-col a:hover i {
  color: var(--orange-main);
}

@media (max-width: 991px) {
  .nav-dropdown {
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
  }
  .nav-dropdown-trigger {
    width: 100%;
    justify-content: space-between;
    padding: 10px 14px;
  }
  .mega-menu {
    position: static;
    transform: none;
    min-width: 100%;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    border: none;
    padding: 10px 0 0 15px;
    display: none;
    margin-top: 0;
  }
  .nav-dropdown.open .mega-menu {
    display: block;
  }
  .mega-menu-inner {
    grid-template-columns: 1fr;
    gap: 20px;
  }
}