/* ==========================================================================
   ENERGY SOLUTIONS VSP - MAIN DESIGN SYSTEM STYLESHEET
   Domain: energysolutionsvsp.com
   Industrial B2B Theme: Deep Navy, Steel Grey, Electric Blue, Orange Accents
   ========================================================================== */

/* 1. CSS CUSTOM PROPERTIES (DESIGN TOKENS) */
:root {
  /* Brand Palette */
  --color-navy-dark: #090d16;
  --color-navy: #0f172a;
  --color-navy-light: #1e293b;
  --color-steel-dark: #334155;
  --color-steel: #64748b;
  --color-steel-light: #94a3b8;
  --color-bg-light: #f8fafc;
  --color-white: #ffffff;

  /* Accent Colors */
  --color-electric-blue: #0ea5e9;
  --color-electric-hover: #0284c7;
  --color-orange-accent: #f97316;
  --color-orange-hover: #ea580c;
  --color-whatsapp: #25d366;
  --color-whatsapp-hover: #1da851;

  /* Status Colors */
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-danger: #ef4444;

  /* Typography */
  --font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  --font-family-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  /* Spacing System */
  --space-xs: 0.25rem;  /* 4px */
  --space-sm: 0.5rem;   /* 8px */
  --space-md: 1rem;     /* 16px */
  --space-lg: 1.5rem;   /* 24px */
  --space-xl: 2.5rem;   /* 40px */
  --space-2xl: 4rem;    /* 64px */

  /* Borders & Radius */
  --border-color: #e2e8f0;
  --border-color-dark: #334155;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;

  /* Elevations / Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.15), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 20px rgba(14, 165, 233, 0.25);

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
  --transition-smooth: 0.35s cubic-bezier(0.4, 0, 0.2, 1);

  /* Layout */
  --container-max-width: 1240px;
  --header-height: 80px;
}

/* 2. BASE RESET & ACCESSIBILITY */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-steel-dark);
  background-color: var(--color-bg-light);
  overflow-x: hidden;
}

img, svg {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-electric-blue);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-electric-hover);
}

/* Accessible Skip Link */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--color-orange-accent);
  color: var(--color-white);
  padding: 0.75rem 1.25rem;
  font-weight: 700;
  border-radius: var(--radius-sm);
  z-index: 10000;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 1rem;
  outline: 3px solid var(--color-navy);
}

/* Visible Focus Indicator */
:focus-visible {
  outline: 3px solid var(--color-electric-blue);
  outline-offset: 2px;
}

/* 3. TYPOGRAPHY & UTILITIES */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-navy);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

h1 { font-size: 2.75rem; }
h2 { font-size: 2.125rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.125rem; }

p {
  margin-bottom: 1rem;
}

.text-muted { color: var(--color-steel); }
.text-center { text-align: center; }
.text-left { text-align: left; }
.w-full { width: 100%; }
.mt-4 { margin-top: 1rem; }
.pt-4 { padding-top: 1rem; }
.mb-3 { margin-bottom: 0.75rem; }
.border-top { border-top: 1px solid var(--border-color); }

.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-md);
  padding-right: var(--space-md);
}

.section-padding {
  padding-top: var(--space-2xl);
  padding-bottom: var(--space-2xl);
}

.section-header {
  margin-bottom: var(--space-xl);
}

.section-title {
  font-size: 2.25rem;
  color: var(--color-navy);
  position: relative;
  display: inline-block;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--color-steel);
  max-width: 680px;
  margin-top: 0.5rem;
}

.section-header.text-center .section-subtitle {
  margin-left: auto;
  margin-right: auto;
}

/* Badge & Tag Elements */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--radius-sm);
}

.badge-primary {
  background-color: rgba(14, 165, 233, 0.12);
  color: var(--color-electric-blue);
}

.badge-warning {
  background-color: rgba(249, 115, 22, 0.12);
  color: var(--color-orange-accent);
}

/* 4. BUTTONS & CONTROLS */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-size: 0.9375rem;
  font-weight: 600;
  line-height: 1;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
  gap: 0.5rem;
}

.btn-primary {
  background-color: var(--color-orange-accent);
  color: var(--color-white);
}
.btn-primary:hover {
  background-color: var(--color-orange-hover);
  color: var(--color-white);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--color-navy);
  color: var(--color-white);
}
.btn-secondary:hover {
  background-color: var(--color-navy-light);
  color: var(--color-white);
}

.btn-outline {
  background-color: transparent;
  border-color: var(--color-steel-light);
  color: var(--color-navy);
}
.btn-outline:hover {
  border-color: var(--color-navy);
  background-color: rgba(15, 23, 42, 0.04);
}

.btn-whatsapp {
  background-color: var(--color-whatsapp);
  color: var(--color-white);
}
.btn-whatsapp:hover {
  background-color: var(--color-whatsapp-hover);
  color: var(--color-white);
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.0625rem;
}

/* 5. SITE HEADER & NAVIGATION */
.site-header {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background-color: var(--color-navy);
  border-bottom: 1px solid var(--color-navy-light);
  z-index: 1000;
  transition: background-color var(--transition-fast), box-shadow var(--transition-fast);
}

.site-header.is-scrolled {
  box-shadow: var(--shadow-lg);
  background-color: rgba(15, 23, 42, 0.96);
  backdrop-filter: blur(8px);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--color-white);
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.03em;
}

.brand-logo svg {
  width: 38px;
  height: 38px;
}

.brand-name {
  color: var(--color-white);
}
.brand-highlight {
  color: var(--color-electric-blue);
}

.site-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 1.75rem;
}

.nav-list a {
  color: #cbd5e1;
  font-weight: 500;
  font-size: 0.9375rem;
  padding: 0.5rem 0;
  position: relative;
}

.nav-list a:hover,
.nav-list a.active {
  color: var(--color-white);
}

.nav-list a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-orange-accent);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Mobile Hamburger Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-white);
  cursor: pointer;
  padding: 0.5rem;
}
.mobile-menu-toggle svg {
  width: 28px;
  height: 28px;
}

/* 6. HERO SECTION */
.hero-section {
  position: relative;
  background-color: var(--color-navy-dark);
  color: var(--color-white);
  padding-top: var(--space-2xl);
  padding-bottom: var(--space-2xl);
  min-height: 540px;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-background-pattern {
  position: absolute;
  top: 0;
  right: 0;
  width: 60%;
  height: 100%;
  opacity: 0.15;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 720px;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: rgba(14, 165, 233, 0.15);
  border: 1px solid rgba(14, 165, 233, 0.3);
  color: var(--color-electric-blue);
  padding: 0.35rem 0.85rem;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
}

.hero-title {
  color: var(--color-white);
  font-size: 3.125rem;
  line-height: 1.15;
  margin-bottom: 1.25rem;
}

.hero-description {
  font-size: 1.1875rem;
  color: #94a3b8;
  line-height: 1.6;
  margin-bottom: 2rem;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

/* 7. TRUST & STRENGTHS SECTION */
.trust-section {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--border-color);
}

.strengths-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

.strength-card {
  padding: 1.75rem;
  background-color: var(--color-bg-light);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.strength-card:hover {
  transform: translateY(-2px);
  border-color: var(--color-electric-blue);
}

.strength-icon {
  width: 48px;
  height: 48px;
  background-color: rgba(14, 165, 233, 0.1);
  color: var(--color-electric-blue);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}

.strength-icon svg {
  width: 24px;
  height: 24px;
}

/* 8. PRODUCTS CATALOGUE SECTION */
.products-section {
  background-color: var(--color-bg-light);
}

.catalog-controls {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  margin-bottom: var(--space-xl);
  background-color: var(--color-white);
  padding: 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.search-box {
  position: relative;
  width: 100%;
}

.search-box input {
  width: 100%;
  padding: 0.85rem 1rem 0.85rem 2.75rem;
  font-size: 1rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  background-color: var(--color-bg-light);
  color: var(--color-navy);
}

.search-icon {
  position: absolute;
  left: 0.85rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-steel);
  pointer-events: none;
}

.search-reset-btn {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  font-size: 1.25rem;
  color: var(--color-steel);
  cursor: pointer;
  display: none;
}

.category-tabs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.category-filter-btn {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
  font-weight: 600;
  background-color: var(--color-bg-light);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--color-steel-dark);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.category-filter-btn:hover,
.category-filter-btn.active {
  background-color: var(--color-navy);
  color: var(--color-white);
  border-color: var(--color-navy);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-lg);
}

.product-card {
  background-color: var(--color-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-electric-blue);
}

.product-card-image {
  position: relative;
  background-color: var(--color-navy-dark);
  height: 200px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-card-image svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.product-badge {
  position: absolute;
  top: 0.75rem;
  left: 0.75rem;
  background-color: rgba(15, 23, 42, 0.85);
  color: var(--color-electric-blue);
  border: 1px solid rgba(14, 165, 233, 0.4);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.25rem 0.6rem;
  border-radius: var(--radius-sm);
}

.product-card-body {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.product-title {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.product-desc {
  font-size: 0.9375rem;
  color: var(--color-steel);
  margin-bottom: 1rem;
}

.product-highlights h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-steel-dark);
  margin-bottom: 0.35rem;
}

.product-highlights ul {
  padding-left: 1.2rem;
  font-size: 0.875rem;
  color: var(--color-steel-dark);
}

.product-card-footer {
  padding: 1.25rem 1.5rem;
  background-color: var(--color-bg-light);
  border-top: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.product-card-footer .btn {
  flex: 1;
  font-size: 0.875rem;
  padding: 0.6rem 0.75rem;
}

/* 9. SERVICES SECTION */
.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-lg);
}

.service-card {
  background-color: var(--color-white);
  border: 1px solid var(--border-color);
  padding: 2rem;
  border-radius: var(--radius-md);
  transition: transform var(--transition-fast);
}

.service-card:hover {
  transform: translateY(-2px);
  border-color: var(--color-orange-accent);
}

.service-number {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-electric-blue);
  margin-bottom: 0.75rem;
}

/* 10. ENQUIRY / FORM SECTION */
.enquiry-section {
  background-color: var(--color-white);
}

.enquiry-container-grid {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: var(--space-2xl);
}

.enquiry-info-box {
  background-color: var(--color-navy);
  color: var(--color-white);
  padding: 2.5rem;
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.enquiry-info-box h2 {
  color: var(--color-white);
}

.contact-info-list {
  list-style: none;
  margin-top: 1.5rem;
}

.contact-info-list li {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.contact-icon {
  color: var(--color-electric-blue);
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.enquiry-form-box {
  background-color: var(--color-bg-light);
  padding: 2.5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.form-group {
  display: flex;
  flex-direction: column;
}

.form-group.full-width {
  grid-column: span 2;
}

.form-label {
  font-weight: 600;
  font-size: 0.875rem;
  margin-bottom: 0.4rem;
  color: var(--color-navy);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 0.9375rem;
  font-family: var(--font-family);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  background-color: var(--color-white);
  color: var(--color-navy);
  transition: border-color var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  border-color: var(--color-electric-blue);
  outline: none;
}

.form-input.is-invalid,
.form-select.is-invalid,
.form-textarea.is-invalid {
  border-color: var(--color-danger);
}

.form-error-msg {
  color: var(--color-danger);
  font-size: 0.8rem;
  margin-top: 0.25rem;
}

.form-actions-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

/* 11. MODAL WINDOWS */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(9, 13, 22, 0.75);
  backdrop-filter: blur(4px);
  z-index: 9000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
  padding: 1rem;
}

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

.modal-container {
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 850px;
  max-height: 90vh;
  overflow-y: auto;
  position: relative;
  padding: 2rem;
  box-shadow: var(--shadow-lg);

  transform: translateY(20px);
  transition: transform var(--transition-normal);
}

.modal-backdrop.is-open .modal-container {
  transform: translateY(0);
}

.modal-close-btn {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: none;
  border: none;
  font-size: 2rem;
  line-height: 1;
  color: var(--color-steel);
  cursor: pointer;
}

.modal-body {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 2rem;
  margin-top: 1.5rem;
}

.specs-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 0.75rem;
  font-size: 0.875rem;
}

.specs-table th,
.specs-table td {
  padding: 0.6rem 0.8rem;
  border-bottom: 1px solid var(--border-color);
  text-align: left;
}

.specs-table th {
  background-color: var(--color-bg-light);
  color: var(--color-navy);
  font-weight: 600;
  width: 40%;
}

/* 12. FOOTER */
.site-footer {
  background-color: var(--color-navy-dark);
  color: #94a3b8;
  padding-top: var(--space-2xl);
  padding-bottom: var(--space-lg);
  border-top: 1px solid var(--color-navy-light);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: var(--space-xl);
  margin-bottom: var(--space-2xl);
}

.footer-brand p {
  margin-top: 1rem;
  font-size: 0.9375rem;
  line-height: 1.6;
}

.footer-col h4 {
  color: var(--color-white);
  font-size: 1rem;
  margin-bottom: 1.25rem;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.65rem;
}

.footer-links a {
  color: #cbd5e1;
  font-size: 0.9rem;
}

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

.footer-bottom {
  border-top: 1px solid var(--color-navy-light);
  padding-top: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
}

/* Back to Top Floating Button */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--color-navy);
  color: var(--color-white);
  border: 1px solid var(--color-steel-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-fast), transform var(--transition-fast);
  z-index: 800;
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  background-color: var(--color-orange-accent);
  border-color: var(--color-orange-accent);
  transform: translateY(-3px);
}

/* 13. PREFERS REDUCED MOTION */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}