/* ==========================================================================
   ElectricityBillCalc.online - Solid White & Sky Blue Theme (Hard Text High Contrast)
   ========================================================================== */

:root {
  /* Solid White & Crisp Light Palette */
  --bg-main: #ffffff;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f9ff;
  --bg-subtle: #f0f9ff;
  --bg-input: #ffffff;
  
  /* Crisp Borders */
  --border-color: #cbd5e1;
  --border-focus: #0284c7;
  --border-sky-light: #bae6fd;
  
  /* Hard Texts (High Contrast Dark Blacks & Slates) */
  --text-primary: #020617;     /* Hardest black/slate */
  --text-secondary: #1e293b;   /* Hard dark slate */
  --text-muted: #334155;       /* Strong legible dark slate */
  
  /* Sky Blue Brand Accents */
  --accent-sky: #0284c7;
  --accent-sky-light: #0ea5e9;
  --accent-sky-dark: #0369a1;
  --accent-sky-soft: #e0f2fe;
  
  --accent-amber: #d97706;
  --accent-emerald: #059669;
  --accent-rose: #e11d48;
  
  /* Gradients */
  --grad-primary: linear-gradient(135deg, #0284c7 0%, #0ea5e9 100%);
  --grad-sky-banner: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
  --grad-card: #ffffff;
  
  /* Typography & Layout */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 8px 20px rgba(0, 0, 0, 0.08);
  
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
}

/* Dark Theme Toggle Override */
[data-theme="dark"] {
  --bg-main: #0a0f1d;
  --bg-surface: #111827;
  --bg-card: #111827;
  --bg-card-hover: #1e293b;
  --bg-subtle: #1e293b;
  --bg-input: #0f172a;
  
  --border-color: #334155;
  --border-focus: #38bdf8;
  --border-sky-light: #0284c7;
  
  --text-primary: #ffffff;
  --text-secondary: #e2e8f0;
  --text-muted: #94a3b8;
  
  --accent-sky: #38bdf8;
  --accent-sky-light: #0ea5e9;
  --accent-sky-soft: rgba(56, 189, 248, 0.15);
  
  --grad-sky-banner: linear-gradient(135deg, #111827 0%, #1e293b 100%);
  --grad-card: #111827;
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.5);
}

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

html {
  font-family: var(--font-family);
  font-size: 16px;
  line-height: 1.6;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg-main);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition-normal), color var(--transition-normal);
  font-weight: 500;
}

a {
  color: var(--accent-sky);
  text-decoration: none;
  font-weight: 600;
  transition: color var(--transition-fast);
}

a:hover {
  text-decoration: underline;
  color: var(--accent-sky-dark);
}

button, input, select {
  font-family: inherit;
  font-size: 1rem;
}

/* Container */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: #ffffff;
  border-bottom: 2px solid var(--border-sky-light);
  box-shadow: 0 2px 8px rgba(2, 132, 199, 0.06);
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

[data-theme="dark"] .site-header {
  background: var(--bg-surface);
  border-bottom-color: var(--border-color);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  gap: 1rem;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.brand-logo:hover {
  text-decoration: none;
}

.logo-bolt {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--grad-primary);
  border-radius: 10px;
  color: #ffffff;
}

.brand-name-part {
  color: var(--accent-sky);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.currency-select-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.currency-select {
  background: #ffffff;
  color: var(--text-primary);
  border: 1.5px solid var(--border-color);
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 700;
  cursor: pointer;
  outline: none;
  transition: border-color var(--transition-fast);
}

[data-theme="dark"] .currency-select {
  background: var(--bg-subtle);
}

.currency-select:hover, .currency-select:focus {
  border-color: var(--accent-sky);
}

.theme-toggle-btn, .btn-header-action {
  background: var(--bg-subtle);
  color: var(--text-primary);
  border: 1.5px solid var(--border-color);
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle-btn:hover, .btn-header-action:hover {
  background: var(--accent-sky-soft);
  border-color: var(--accent-sky);
  color: var(--accent-sky);
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero-section {
  padding: 2.75rem 0 1.75rem;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--accent-sky-soft);
  border: 1.5px solid var(--border-sky-light);
  color: var(--accent-sky-dark);
  padding: 0.4rem 1rem;
  border-radius: 9999px;
  font-size: 0.875rem;
  font-weight: 700;
  margin-bottom: 1.25rem;
}

.hero-title {
  font-size: clamp(2.25rem, 4.5vw, 3.25rem);
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 0.85rem;
  letter-spacing: -0.03em;
  color: var(--text-primary);
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.2rem);
  color: var(--text-secondary);
  max-width: 720px;
  margin: 0 auto;
  font-weight: 500;
  line-height: 1.6;
}

/* ==========================================================================
   Calculator Navigation Tabs
   ========================================================================== */
.calc-nav-wrapper {
  margin: 1.5rem 0 2rem;
  display: flex;
  justify-content: center;
}

.calc-tabs {
  display: flex;
  background: #ffffff;
  border: 2px solid var(--border-sky-light);
  padding: 0.35rem;
  border-radius: var(--radius-lg);
  gap: 0.35rem;
  max-width: 100%;
  overflow-x: auto;
  box-shadow: var(--shadow-sm);
}

[data-theme="dark"] .calc-tabs {
  background: var(--bg-surface);
  border-color: var(--border-color);
}

.tab-btn {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.75rem 1.4rem;
  border-radius: var(--radius-md);
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.tab-btn svg {
  width: 18px;
  height: 18px;
}

.tab-btn:hover {
  color: var(--accent-sky);
  background: var(--accent-sky-soft);
}

.tab-btn.active {
  background: var(--grad-primary);
  color: #ffffff;
}

/* ==========================================================================
   Main Calculator Grid Layout
   ========================================================================== */
.calc-grid {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: 2rem;
  margin-bottom: 3rem;
  align-items: start;
}

@media (max-width: 960px) {
  .calc-grid {
    grid-template-columns: 1fr;
  }
}

/* Card Styling */
.card {
  background: #ffffff;
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  transition: border-color var(--transition-normal), box-shadow var(--transition-normal);
}

[data-theme="dark"] .card {
  background: var(--bg-card);
}

.card:hover {
  border-color: var(--border-sky-light);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  padding-bottom: 0.85rem;
  border-bottom: 1.5px solid var(--border-color);
}

.card-title {
  font-size: 1.35rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.card-title-icon {
  color: var(--accent-sky);
}

/* ==========================================================================
   Form Fields, Inputs & Sliders
   ========================================================================== */
.form-group {
  margin-bottom: 1.35rem;
}

.label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
}

.form-label {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.tooltip-icon {
  cursor: help;
  color: var(--accent-sky);
  width: 16px;
  height: 16px;
}

.input-with-affix {
  position: relative;
  display: flex;
  align-items: center;
}

.input-affix-prefix, .input-affix-suffix {
  position: absolute;
  color: var(--text-muted);
  font-weight: 700;
  font-size: 1rem;
  pointer-events: none;
}

.input-affix-prefix {
  left: 1rem;
}

.input-affix-suffix {
  right: 1rem;
}

.form-input {
  width: 100%;
  background: #ffffff;
  color: var(--text-primary);
  border: 1.5px solid var(--border-color);
  padding: 0.85rem 1rem;
  border-radius: var(--radius-md);
  font-size: 1.05rem;
  font-weight: 700;
  outline: none;
  transition: all var(--transition-fast);
}

[data-theme="dark"] .form-input {
  background: var(--bg-input);
}

.form-input:focus {
  border-color: var(--border-focus);
}

.input-with-affix .form-input.has-prefix {
  padding-left: 2.4rem;
}

.input-with-affix .form-input.has-suffix {
  padding-right: 3.75rem;
}

/* Range Slider */
.slider-container {
  margin-top: 0.65rem;
}

.range-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: var(--accent-sky-soft);
  outline: none;
  transition: background var(--transition-fast);
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent-sky);
  cursor: pointer;
  transition: transform var(--transition-fast);
}

.range-slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

.range-slider::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent-sky);
  cursor: pointer;
  border: none;
}

/* Segmented Control / Toggle Buttons */
.segmented-control {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--bg-subtle);
  border: 1.5px solid var(--border-sky-light);
  padding: 0.35rem;
  border-radius: var(--radius-md);
  gap: 0.35rem;
  margin-bottom: 1.35rem;
}

.seg-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.6rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.seg-btn.active {
  background: #ffffff;
  color: var(--accent-sky);
  box-shadow: var(--shadow-sm);
}

[data-theme="dark"] .seg-btn.active {
  background: var(--bg-surface);
}

/* Two-column subgrid in forms */
.form-row-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}

@media (max-width: 540px) {
  .form-row-2 {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   Tiered / Slab Rate Editor
   ========================================================================== */
.slab-info-banner {
  background: var(--accent-sky-soft);
  border: 1.5px solid var(--border-sky-light);
  border-radius: var(--radius-md);
  padding: 0.85rem 1.15rem;
  margin-bottom: 1.35rem;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  line-height: 1.5;
}

.slab-table-wrapper {
  overflow-x: auto;
  margin-bottom: 1.25rem;
}

.slab-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
}

.slab-table th {
  text-align: left;
  padding: 0.65rem 0.75rem;
  color: var(--text-primary);
  border-bottom: 2px solid var(--border-color);
  font-weight: 800;
}

.slab-table td {
  padding: 0.65rem 0.5rem;
  vertical-align: middle;
}

.slab-input {
  width: 100%;
  background: #ffffff;
  color: var(--text-primary);
  border: 1.5px solid var(--border-color);
  padding: 0.55rem 0.75rem;
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-weight: 700;
  outline: none;
}

[data-theme="dark"] .slab-input {
  background: var(--bg-input);
}

.slab-input:focus {
  border-color: var(--border-focus);
}

.btn-remove-slab {
  background: rgba(225, 29, 72, 0.1);
  color: var(--accent-rose);
  border: 1.5px solid rgba(225, 29, 72, 0.3);
  border-radius: var(--radius-sm);
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-remove-slab:hover {
  background: var(--accent-rose);
  color: #ffffff;
}

.slab-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.btn-secondary {
  background: #ffffff;
  color: var(--accent-sky);
  border: 2px solid var(--accent-sky);
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius-md);
  font-size: 0.9375rem;
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: all var(--transition-fast);
}

.btn-secondary:hover {
  background: var(--accent-sky);
  color: #ffffff;
}

/* ==========================================================================
   Appliance Energy Audit Builder
   ========================================================================== */
.appliance-controls-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
  gap: 0.85rem;
}

.appliances-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  max-height: 540px;
  overflow-y: auto;
  padding-right: 0.35rem;
}

.appliance-item {
  background: #ffffff;
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 1.15rem;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr auto;
  gap: 0.85rem;
  align-items: center;
  transition: border-color var(--transition-fast);
}

[data-theme="dark"] .appliance-item {
  background: var(--bg-surface);
}

.appliance-item:hover {
  border-color: var(--accent-sky);
}

@media (max-width: 768px) {
  .appliance-item {
    grid-template-columns: 1fr 1fr;
    gap: 0.6rem;
  }
  .appliance-item-info {
    grid-column: span 2;
  }
  .appliance-item-actions {
    grid-column: span 2;
    display: flex;
    justify-content: flex-end;
  }
}

.appliance-meta {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.appliance-icon {
  font-size: 1.35rem;
}

.appliance-name {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--text-primary);
}

.appliance-sub {
  font-size: 0.8125rem;
  color: var(--text-muted);
  font-weight: 600;
}

.compact-input-group {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.compact-label {
  font-size: 0.725rem;
  color: var(--text-primary);
  text-transform: uppercase;
  font-weight: 800;
}

.compact-input {
  background: #ffffff;
  color: var(--text-primary);
  border: 1.5px solid var(--border-color);
  padding: 0.45rem 0.6rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 700;
  width: 100%;
}

[data-theme="dark"] .compact-input {
  background: var(--bg-input);
}

/* ==========================================================================
   Results & Visual Cost Dashboard
   ========================================================================== */
.results-card {
  position: sticky;
  top: 90px;
  border: 2px solid var(--border-sky-light);
}

.bill-hero-box {
  background: var(--grad-sky-banner);
  border: 2px solid var(--border-sky-light);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  text-align: center;
  margin-bottom: 1.5rem;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.bill-hero-label {
  font-size: 0.875rem;
  font-weight: 800;
  color: var(--accent-sky-dark);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.35rem;
}

.bill-hero-amount {
  font-size: clamp(2.4rem, 3.8vw, 3.25rem);
  font-weight: 900;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  line-height: 1.1;
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 0.25rem;
}

.bill-hero-period {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--text-muted);
}

.bill-hero-kwh-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  background: #ffffff;
  color: var(--accent-sky-dark);
  border: 1.5px solid var(--border-sky-light);
  padding: 0.35rem 0.95rem;
  border-radius: 9999px;
  font-size: 0.875rem;
  font-weight: 700;
  margin-top: 0.85rem;
  box-shadow: var(--shadow-sm);
}

/* Cost Horizons Grid (Daily / Weekly / Monthly / Annual) */
.horizons-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.65rem;
  margin-bottom: 1.5rem;
}

@media (max-width: 480px) {
  .horizons-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.horizon-card {
  background: #ffffff;
  border: 1.5px solid var(--border-color);
  padding: 0.75rem 0.5rem;
  border-radius: var(--radius-md);
  text-align: center;
}

[data-theme="dark"] .horizon-card {
  background: var(--bg-surface);
}

.horizon-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  font-weight: 800;
}

.horizon-val {
  font-size: 1.1rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-top: 0.2rem;
}

/* SVG Chart & Breakdown */
.chart-breakdown-section {
  display: flex;
  align-items: center;
  gap: 1.35rem;
  margin-bottom: 1.5rem;
  background: var(--bg-subtle);
  border: 1.5px solid var(--border-sky-light);
  padding: 1.15rem;
  border-radius: var(--radius-lg);
}

@media (max-width: 480px) {
  .chart-breakdown-section {
    flex-direction: column;
    text-align: center;
  }
}

.chart-wrapper {
  width: 115px;
  height: 115px;
  flex-shrink: 0;
  position: relative;
}

.chart-legend {
  flex-grow: 1;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.legend-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.875rem;
}

.legend-color-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-primary);
  font-weight: 700;
}

.legend-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex-shrink: 0;
}

.legend-value {
  font-weight: 800;
  color: var(--text-primary);
}

/* Itemized Details List */
.bill-line-items {
  border-top: 1.5px solid var(--border-color);
  padding-top: 1.15rem;
  margin-bottom: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  font-size: 0.9375rem;
}

.line-item {
  display: flex;
  justify-content: space-between;
  color: var(--text-secondary);
  font-weight: 600;
}

.line-item strong {
  color: var(--text-primary);
  font-weight: 800;
}

.line-item.total {
  border-top: 2px dashed var(--border-color);
  padding-top: 0.6rem;
  margin-top: 0.35rem;
  font-weight: 800;
  color: var(--text-primary);
  font-size: 1.1rem;
}

/* Action Buttons (Print, Share, Reset) */
.results-action-buttons {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.btn-primary {
  background: var(--grad-primary);
  color: #ffffff;
  border: none;
  padding: 0.85rem 1rem;
  border-radius: var(--radius-md);
  font-weight: 800;
  font-size: 0.95rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: all var(--transition-fast);
}

.btn-primary:hover {
  background: var(--accent-sky-dark);
}

.btn-primary:active {
  transform: translateY(0);
}

/* ==========================================================================
   Savings What-If Simulator
   ========================================================================== */
.simulator-card {
  margin-bottom: 3rem;
  background: #ffffff;
  border: 2px solid var(--border-sky-light);
}

.savings-banner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 1.75rem;
  align-items: center;
}

@media (max-width: 680px) {
  .savings-banner {
    grid-template-columns: 1fr;
  }
}

.savings-highlight-box {
  background: var(--accent-sky-soft);
  border: 2px solid var(--border-sky-light);
  border-radius: var(--radius-lg);
  padding: 1.5rem 2rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.savings-amount {
  font-size: 2rem;
  font-weight: 900;
  color: var(--accent-sky-dark);
}

.savings-subtitle {
  font-size: 0.875rem;
  color: var(--text-primary);
  font-weight: 700;
}

/* ==========================================================================
   Informational & SEO Content Sections
   ========================================================================== */
.content-section {
  margin-bottom: 3.5rem;
}

.section-header {
  text-align: center;
  margin-bottom: 2rem;
}

.section-badge {
  font-size: 0.875rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--accent-sky-dark);
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
  display: block;
}

.section-title {
  font-size: clamp(1.75rem, 3vw, 2.35rem);
  font-weight: 900;
  letter-spacing: -0.02em;
  margin-bottom: 0.6rem;
  color: var(--text-primary);
}

.section-desc {
  color: var(--text-secondary);
  max-width: 720px;
  margin: 0 auto;
  font-size: 1.05rem;
  font-weight: 500;
}

/* Feature / Formula Cards Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: #ffffff;
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

[data-theme="dark"] .feature-card {
  background: var(--bg-card);
}

.feature-card:hover {
  transform: translateY(-3px);
  border-color: var(--accent-sky);
}

.feature-icon-box {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--accent-sky-soft);
  color: var(--accent-sky-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.15rem;
}

.feature-title {
  font-size: 1.2rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.feature-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.65;
  font-weight: 500;
}

.code-badge {
  display: inline-block;
  background: var(--bg-subtle);
  color: var(--accent-sky-dark);
  border: 1px solid var(--border-sky-light);
  padding: 0.35rem 0.65rem;
  border-radius: 6px;
  font-family: monospace;
  font-size: 0.875rem;
  font-weight: 700;
  margin-top: 0.75rem;
}

/* ==========================================================================
   Appliance Reference Wattage Table
   ========================================================================== */
.table-filter-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  gap: 1rem;
  flex-wrap: wrap;
}

.search-input {
  max-width: 340px;
}

.seo-table-container {
  overflow-x: auto;
  background: #ffffff;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

[data-theme="dark"] .seo-table-container {
  background: var(--bg-card);
}

.seo-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.seo-table th {
  background: var(--bg-subtle);
  padding: 1.1rem 1.25rem;
  color: var(--text-primary);
  font-weight: 800;
  border-bottom: 2px solid var(--border-color);
}

.seo-table td {
  padding: 0.95rem 1.25rem;
  border-bottom: 1.5px solid var(--border-color);
  color: var(--text-secondary);
  font-weight: 500;
}

.seo-table tbody tr:hover {
  background: var(--accent-sky-soft);
}

.seo-table .appliance-col {
  font-weight: 700;
  color: var(--text-primary);
}

/* ==========================================================================
   Interactive FAQ Accordion
   ========================================================================== */
.faq-accordion {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.95rem;
}

.faq-item {
  background: #ffffff;
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-fast);
}

[data-theme="dark"] .faq-item {
  background: var(--bg-card);
}

.faq-item:hover {
  border-color: var(--accent-sky);
}

.faq-question {
  width: 100%;
  background: none;
  border: none;
  padding: 1.25rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  text-align: left;
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-primary);
  cursor: pointer;
  gap: 1rem;
}

.faq-icon {
  width: 22px;
  height: 22px;
  transition: transform var(--transition-fast);
  color: var(--accent-sky);
  flex-shrink: 0;
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s ease;
  padding: 0 1.5rem;
  color: var(--text-secondary);
  font-size: 0.98rem;
  line-height: 1.7;
  font-weight: 500;
}

.faq-item.active .faq-answer {
  max-height: 400px;
  padding-bottom: 1.35rem;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  margin-top: auto;
  background: #ffffff;
  border-top: 2px solid var(--border-sky-light);
  padding: 3rem 0 2rem;
  color: var(--text-secondary);
}

[data-theme="dark"] .site-footer {
  background: var(--bg-surface);
  border-top-color: var(--border-color);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 2.5rem;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

.footer-brand-desc {
  font-size: 0.95rem;
  margin-top: 0.85rem;
  max-width: 400px;
  line-height: 1.65;
  color: var(--text-secondary);
}

.footer-col-title {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 600;
}

.footer-links a:hover {
  color: var(--accent-sky);
}

.footer-bottom {
  border-top: 1.5px solid var(--border-color);
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 600;
  flex-wrap: wrap;
  gap: 1rem;
}

/* ==========================================================================
   Toast Notification & Modal
   ========================================================================== */
.toast-notification {
  position: fixed;
  bottom: 25px;
  right: 25px;
  background: #020617;
  color: #ffffff;
  border: 1.5px solid var(--accent-sky);
  padding: 0.85rem 1.35rem;
  border-radius: var(--radius-md);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  z-index: 1000;
  transform: translateY(120%);
  opacity: 0;
  font-weight: 700;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.toast-notification.show {
  transform: translateY(0);
  opacity: 1;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.modal-backdrop.active {
  opacity: 1;
  pointer-events: auto;
}

.modal-content {
  background: #ffffff;
  border: 2px solid var(--border-sky-light);
  border-radius: var(--radius-xl);
  max-width: 650px;
  width: 100%;
  max-height: 85vh;
  overflow-y: auto;
  padding: 2.25rem;
  position: relative;
  box-shadow: var(--shadow-lg);
}

.modal-close-btn {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: var(--bg-subtle);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 34px;
  height: 34px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ==========================================================================
   Print Stylesheet (@media print)
   ========================================================================== */
@media print {
  body {
    background: #ffffff !important;
    color: #000000 !important;
  }
  
  .site-header, .calc-nav-wrapper, .simulator-card, .content-section, 
  .site-footer, .results-action-buttons, .theme-toggle-btn, .currency-select-wrapper,
  .btn-remove-slab, .slab-actions, .appliance-controls-bar, .appliance-item-actions {
    display: none !important;
  }
  
  .container {
    max-width: 100% !important;
    padding: 0 !important;
  }
  
  .calc-grid {
    grid-template-columns: 1fr !important;
    gap: 1rem !important;
  }
  
  .card {
    border: 1.5px solid #000000 !important;
    background: #ffffff !important;
    box-shadow: none !important;
    padding: 1rem !important;
  }
  
  .results-card {
    position: static !important;
  }
  
  .print-receipt-header {
    display: block !important;
    border-bottom: 2px solid #000000;
    padding-bottom: 1rem;
    margin-bottom: 1.5rem;
  }
  
  .print-receipt-header h1 {
    font-size: 1.5rem;
  }
}

.print-receipt-header {
  display: none;
}

/* ==========================================================================
   Advertisement Slots Styling
   ========================================================================== */
.ad-slot {
  margin: 1.5rem auto;
  text-align: center;
  max-width: 100%;
  overflow-x: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  clear: both;
}

.ad-label {
  font-size: 0.65rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #94a3b8;
  margin-bottom: 0.25rem;
}

.ad-728x90 {
  min-height: 90px;
  width: 100%;
}

.ad-300x250 {
  min-height: 250px;
  width: 300px;
}

.ad-160x300 {
  min-height: 300px;
  width: 160px;
}

.ad-native {
  width: 100%;
  max-width: 1000px;
  min-height: 120px;
}

.ad-row-flex {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin: 1.75rem auto;
}

@media print {
  .ad-slot, .ad-label, .ad-row-flex {
    display: none !important;
  }
}