/*
 * Quantum Solid Power - Design System
 * Navy blue theme with clean, professional look
 *
 * COLOR PALETTE:
 * --navy-900: #0a1628  (darkest - footer bg)
 * --navy-800: #0f2040  (dark sections bg)
 * --navy-700: #152d54  (navbar bg)
 * --navy-600: #1a3a6b  (primary buttons, accents)
 * --navy-500: #1e4d8f  (hover states)
 * --navy-400: #2a6ab8  (links, highlights)
 * --navy-300: #4a8fd4  (light accents)
 * --navy-200: #7db3e8  (subtle highlights)
 * --navy-100: #c0d9f5  (light bg tint)
 * --navy-50:  #e8f0fa  (lightest bg)
 *
 * --accent:   #2ecc71  (green accent for energy/eco)
 * --accent-dark: #27ae60
 * --gold:     #f39c12  (for highlights, stats)
 * --white:    #ffffff
 * --gray-50:  #f8f9fa
 * --gray-100: #f1f3f5
 * --gray-200: #e9ecef
 * --gray-300: #dee2e6
 * --gray-500: #6c757d
 * --gray-700: #495057
 * --gray-900: #212529
 */

:root {
  --navy-900: #0a1628;
  --navy-800: #0f2040;
  --navy-700: #152d54;
  --navy-600: #1a3a6b;
  --navy-500: #1e4d8f;
  --navy-400: #2a6ab8;
  --navy-300: #4a8fd4;
  --navy-200: #7db3e8;
  --navy-100: #c0d9f5;
  --navy-50: #e8f0fa;

  --accent: #2ecc71;
  --accent-dark: #27ae60;
  --accent-light: #d4efdf;
  --gold: #f39c12;

  --white: #ffffff;
  --gray-50: #f8f9fa;
  --gray-100: #f1f3f5;
  --gray-200: #e9ecef;
  --gray-300: #dee2e6;
  --gray-500: #6c757d;
  --gray-700: #495057;
  --gray-900: #212529;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 25px rgba(0,0,0,0.15);

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  --transition: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--gray-900);
  background: var(--white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--navy-400);
  text-decoration: none;
  transition: color var(--transition);
}
a:hover {
  color: var(--navy-500);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--navy-800);
}

/* ============================================================
   LAYOUT UTILITIES
   ============================================================ */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 80px 0;
}

.section--dark {
  background: var(--navy-800);
  color: var(--white);
}
.section--dark h2,
.section--dark h3 {
  color: var(--white);
}

.section--light {
  background: var(--navy-50);
}

.section--gray {
  background: var(--gray-50);
}

.section__header {
  text-align: center;
  margin-bottom: 48px;
}

.section__title {
  font-size: 2.25rem;
  margin-bottom: 16px;
}

.section__subtitle {
  font-size: 1.125rem;
  color: var(--gray-500);
  max-width: 600px;
  margin: 0 auto;
}

.section--dark .section__subtitle {
  color: var(--navy-200);
}

/* ============================================================
   GRID
   ============================================================ */
.grid {
  display: grid;
  gap: 24px;
}
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 992px) {
  .grid--3, .grid--4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 576px) {
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
}

/* ============================================================
   NAVBAR
   ============================================================ */
#navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: transparent;
  transition: background var(--transition), box-shadow var(--transition);
  padding: 16px 0;
}

#navbar.scrolled {
  background: rgba(15, 32, 64, 0.97);
  box-shadow: var(--shadow-lg);
  padding: 8px 0;
}

.navbar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar__logo img {
  height: 48px;
  width: auto;
}

.navbar__links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.navbar__links a {
  color: var(--white);
  font-weight: 500;
  font-size: 0.95rem;
  opacity: 0.9;
  transition: opacity var(--transition);
}
.navbar__links a:hover {
  opacity: 1;
  color: var(--accent);
}

.navbar__lang {
  display: flex;
  gap: 4px;
  margin-left: 16px;
}

.navbar__lang button {
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.3);
  color: var(--white);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 600;
  transition: all var(--transition);
}
.navbar__lang button.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--white);
}
.navbar__lang button:hover:not(.active) {
  background: rgba(255,255,255,0.25);
}

/* Hamburger */
#hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
#hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--white);
  transition: all var(--transition);
}
#hamburger.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
#hamburger.open span:nth-child(2) { opacity: 0; }
#hamburger.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* Mobile menu */
#mobile-menu {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--navy-900);
  z-index: 999;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 24px;
}
#mobile-menu.open {
  display: flex;
}
#mobile-menu a {
  color: var(--white);
  font-size: 1.5rem;
  font-weight: 600;
}

@media (max-width: 768px) {
  .navbar__links { display: none; }
  #hamburger { display: flex; }
}

/* ============================================================
   HERO SECTION
   ============================================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, var(--navy-900) 0%, var(--navy-700) 50%, var(--navy-600) 100%);
  overflow: hidden;
}

.hero__bg-video {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: 0.25;
}

.hero__content {
  position: relative;
  z-index: 2;
  max-width: 700px;
  color: var(--white);
}

.hero__title {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 20px;
  color: var(--white);
}

.hero__subtitle {
  font-size: 1.25rem;
  opacity: 0.85;
  margin-bottom: 32px;
  line-height: 1.6;
}

.hero__buttons {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

@media (max-width: 768px) {
  .hero__title { font-size: 2.25rem; }
  .hero__subtitle { font-size: 1rem; }
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition);
  border: 2px solid transparent;
  text-decoration: none;
}

.btn--primary {
  background: var(--accent);
  color: var(--white);
  border-color: var(--accent);
}
.btn--primary:hover {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
  color: var(--white);
}

.btn--outline {
  background: transparent;
  color: var(--white);
  border-color: var(--white);
}
.btn--outline:hover {
  background: var(--white);
  color: var(--navy-800);
}

.btn--navy {
  background: var(--navy-600);
  color: var(--white);
  border-color: var(--navy-600);
}
.btn--navy:hover {
  background: var(--navy-500);
  border-color: var(--navy-500);
  color: var(--white);
}

.btn--lg {
  padding: 16px 36px;
  font-size: 1.1rem;
}

/* ============================================================
   CARDS (Services, Products)
   ============================================================ */
.card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition), box-shadow var(--transition);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.card__icon {
  width: 56px;
  height: 56px;
  background: var(--navy-50);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  font-size: 1.5rem;
}

.card__title {
  font-size: 1.25rem;
  margin-bottom: 8px;
  color: var(--navy-800);
}

.card__text {
  color: var(--gray-500);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Product card */
.product-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition), box-shadow var(--transition);
}
.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}
.product-card.featured {
  border: 2px solid var(--accent);
}

.product-card__image {
  width: 100%;
  height: 220px;
  object-fit: cover;
  background: var(--gray-100);
}

.product-card__body {
  padding: 20px;
}

.product-card__name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--navy-800);
  margin-bottom: 4px;
}

.product-card__type {
  font-size: 0.85rem;
  color: var(--gray-500);
  margin-bottom: 12px;
}

.product-card__specs {
  display: flex;
  gap: 16px;
  margin-bottom: 16px;
}

.product-card__spec {
  text-align: center;
  flex: 1;
}
.product-card__spec-value {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--navy-600);
}
.product-card__spec-label {
  font-size: 0.75rem;
  color: var(--gray-500);
  text-transform: uppercase;
}

.product-card__featured-badge {
  display: inline-block;
  background: var(--accent);
  color: var(--white);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  margin-bottom: 8px;
  text-transform: uppercase;
}

/* ============================================================
   STATS SECTION
   ============================================================ */
.stats {
  display: flex;
  justify-content: center;
  gap: 64px;
  flex-wrap: wrap;
}

.stat {
  text-align: center;
}

.stat__value {
  font-size: 3rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
}

.stat__label {
  font-size: 1rem;
  margin-top: 8px;
  opacity: 0.85;
}

.stat__unit {
  font-size: 1.5rem;
  font-weight: 400;
}

/* ============================================================
   FEATURED PRODUCT
   ============================================================ */
.featured-product {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.featured-product__image {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

.featured-product__name {
  font-size: 2.5rem;
  color: var(--navy-800);
  margin-bottom: 8px;
}

.featured-product__type {
  font-size: 1rem;
  color: var(--gray-500);
  margin-bottom: 16px;
}

.featured-product__desc {
  font-size: 1.05rem;
  color: var(--gray-700);
  margin-bottom: 24px;
  line-height: 1.7;
}

.featured-product__highlights {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 32px;
}

.highlight {
  display: flex;
  align-items: center;
  gap: 8px;
}
.highlight__value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--navy-600);
}
.highlight__label {
  font-size: 0.85rem;
  color: var(--gray-500);
}

@media (max-width: 768px) {
  .featured-product {
    grid-template-columns: 1fr;
  }
  .featured-product__name {
    font-size: 1.75rem;
  }
}

/* ============================================================
   PRODUCT DETAIL PAGE
   ============================================================ */
.product-detail__header {
  padding-top: 120px;
  padding-bottom: 40px;
  background: linear-gradient(135deg, var(--navy-900) 0%, var(--navy-700) 100%);
  color: var(--white);
}

.product-detail__back {
  color: var(--navy-200);
  font-size: 0.9rem;
  margin-bottom: 16px;
  display: inline-block;
}
.product-detail__back:hover {
  color: var(--white);
}

.product-detail__name {
  font-size: 2.5rem;
  color: var(--white);
  margin-bottom: 8px;
}

.product-detail__type {
  font-size: 1.1rem;
  color: var(--navy-200);
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
}
.spec-table tr:nth-child(even) {
  background: var(--gray-50);
}
.spec-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--gray-200);
}
.spec-table td:first-child {
  font-weight: 600;
  color: var(--navy-700);
  width: 40%;
}

/* Gallery */
.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}
.gallery img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: transform var(--transition);
}
.gallery img:hover {
  transform: scale(1.03);
}

/* Video gallery */
.video-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 16px;
}
.video-gallery video {
  width: 100%;
  border-radius: var(--radius-md);
}

/* ============================================================
   CATEGORY FILTER
   ============================================================ */
.category-filter {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.category-filter__btn {
  padding: 8px 20px;
  border: 2px solid var(--navy-200);
  background: transparent;
  color: var(--navy-600);
  border-radius: 9999px;
  cursor: pointer;
  font-weight: 500;
  font-size: 0.9rem;
  transition: all var(--transition);
}
.category-filter__btn:hover {
  background: var(--navy-50);
}
.category-filter__btn.active {
  background: var(--navy-600);
  color: var(--white);
  border-color: var(--navy-600);
}

/* ============================================================
   CONTACT FORM
   ============================================================ */
.contact-form {
  max-width: 600px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--navy-700);
  font-size: 0.9rem;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-family: var(--font-sans);
  transition: border-color var(--transition);
}
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--navy-400);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  background: var(--navy-900);
  color: rgba(255,255,255,0.7);
  padding: 48px 0 24px;
}

.footer__top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 32px;
}

.footer__brand img {
  height: 40px;
  margin-bottom: 16px;
}

.footer__tagline {
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer__heading {
  color: var(--white);
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
}

.footer__links {
  list-style: none;
}
.footer__links li { margin-bottom: 8px; }
.footer__links a {
  color: rgba(255,255,255,0.6);
  font-size: 0.9rem;
}
.footer__links a:hover {
  color: var(--accent);
}

.footer__bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
}

@media (max-width: 768px) {
  .footer__top {
    grid-template-columns: 1fr;
  }
  .footer__bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }
}

/* ============================================================
   ABOUT PAGE
   ============================================================ */
.about-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}
.about-section:nth-child(even) {
  direction: rtl;
}
.about-section:nth-child(even) > * {
  direction: ltr;
}

@media (max-width: 768px) {
  .about-section,
  .about-section:nth-child(even) {
    grid-template-columns: 1fr;
    direction: ltr;
  }
}

/* ============================================================
   PAGE HEADERS (non-home pages)
   ============================================================ */
.page-header {
  padding: 140px 0 60px;
  background: linear-gradient(135deg, var(--navy-900) 0%, var(--navy-700) 100%);
  color: var(--white);
  text-align: center;
}

.page-header__title {
  font-size: 2.5rem;
  color: var(--white);
  margin-bottom: 12px;
}

.page-header__subtitle {
  font-size: 1.1rem;
  color: var(--navy-200);
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================================
   LIGHTBOX (simple image overlay)
   ============================================================ */
.lightbox {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.9);
  z-index: 10000;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}
.lightbox.active {
  display: flex;
}
.lightbox img {
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius-md);
}

/* ============================================================
   ANIMATION UTILITIES
   ============================================================ */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================================
   EV CHARGING SECTION (brief mention)
   ============================================================ */
.ev-brief {
  background: var(--navy-50);
  border-left: 4px solid var(--accent);
  padding: 24px 32px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin-top: 24px;
}

/* ============================================================
   PRINT STYLES
   ============================================================ */
@media print {
  #navbar, .footer, .hero__bg-video { display: none; }
  .hero { min-height: auto; padding: 32px 0; }
  .section { padding: 24px 0; }
}