/* ============================================
   I Power Tech Co., Ltd. — Corporate Website
   ============================================ */

/* ---- CSS Variables ---- */
:root {
  /* Brand Colors */
  --red: #B9131A;
  --red-dark: #921B1E;
  --red-accent: #E01F27;
  --blue: #004480;
  --blue-accent: #6DCEF5;
  --blue-deep: #27408B;

  /* Neutrals */
  --bg-primary: #0A0F1C;
  --bg-card: #111827;
  --bg-surface: #1F2937;
  --bg-surface-hover: #283548;
  --text-primary: #F9FAFB;
  --text-secondary: #9CA3AF;
  --text-muted: #6B7280;
  --border: #374151;

  /* Typography */
  --font-en: 'Inter', sans-serif;
  --font-th: 'Noto Sans Thai', sans-serif;

  /* Spacing */
  --section-padding: 100px 0;
  --container-width: 1200px;
  --container-padding: 0 24px;

  /* Transitions */
  --transition: 0.3s ease;
  --transition-slow: 0.6s ease;
}

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

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

body {
  font-family: var(--font-en);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

body[data-lang="th"] {
  font-family: var(--font-th);
}

a {
  text-decoration: none;
  color: inherit;
}

ul, ol {
  list-style: none;
}

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

/* ---- Container ---- */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--container-padding);
}

/* ---- Section ---- */
.section {
  padding: var(--section-padding);
}

.section--alt {
  background: var(--bg-card);
}

.section-title {
  text-align: center;
  margin-bottom: 60px;
}

.section-title h2 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 12px;
  background: linear-gradient(135deg, var(--text-primary), var(--blue-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-title p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* ---- Fade-in Animation ---- */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* No-JS fallback: show content when JavaScript is unavailable */
.no-js .fade-in {
  opacity: 1;
  transform: none;
}

/* ============================================
   HEADER
   ============================================ */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 16px 0;
  transition: background var(--transition), padding var(--transition), box-shadow var(--transition);
}

.header.scrolled {
  background-color: rgba(10, 15, 28, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  padding: 10px 0;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

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

.header-logo {
  height: 40px;
  width: auto;
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links {
  display: flex;
  gap: 28px;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--red);
  transition: width var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-links a:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 4px;
  border-radius: 2px;
  color: var(--text-primary);
}

/* Language Toggle */
.lang-toggle {
  display: flex;
  align-items: center;
  background: var(--bg-surface);
  border-radius: 20px;
  overflow: hidden;
  border: 1px solid var(--border);
}

.lang-toggle button {
  background: none;
  border: none;
  color: var(--text-primary);
  padding: 6px 14px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  font-family: inherit;
}

.lang-toggle button.active {
  background: var(--red);
  color: white;
}

.lang-toggle button:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 2px;
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 10px;
  margin: -10px;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: all var(--transition);
  border-radius: 2px;
}

.hamburger:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 4px;
  border-radius: 2px;
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   HERO
   ============================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  background: var(--bg-primary);
}

/* Circuit Lines Pattern */
.hero::after {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 0.08;
  background-image:
    linear-gradient(var(--blue) 1px, transparent 1px),
    linear-gradient(90deg, var(--blue) 1px, transparent 1px);
  background-size: 60px 60px;
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 800px;
  padding: 0 24px;
}

.hero-logo {
  width: 580px;
  margin: 0 auto 32px;
  filter: drop-shadow(0 0 40px rgba(109, 206, 245, 0.2));
}

.hero-tagline {
  font-size: 3.2rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 16px;
  color: var(--blue-accent);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
  font-weight: 400;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  border: none;
  font-family: inherit;
}

.btn:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 3px;
}

.btn-primary {
  background: var(--red);
  color: white;
}

.btn-primary:hover {
  background: var(--red-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(185, 19, 26, 0.3);
}

.btn-primary:focus-visible {
  outline-color: var(--blue-accent);
}

.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--blue-accent);
  color: var(--blue-accent);
  transform: translateY(-2px);
}




/* ============================================
   ABOUT
   ============================================ */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 20px;
  font-size: 1.05rem;
  line-height: 1.8;
}

.about-vision {
  margin-top: 32px;
  padding: 20px 24px;
  border-left: 3px solid var(--blue-accent);
  background: rgba(109, 206, 245, 0.04);
  border-radius: 0 8px 8px 0;
}

.about-vision h3 {
  font-size: 1.3rem;
  color: var(--blue-accent);
  margin-bottom: 8px;
  font-weight: 600;
}

.about-vision p {
  font-size: 0.95rem;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  transition: all var(--transition);
}

.stat-card:hover {
  border-color: var(--blue-accent);
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(109, 206, 245, 0.1);
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--blue-accent);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

body:not([data-lang="th"]) .stat-label {
  text-transform: uppercase;
  letter-spacing: 1px;
}

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

.service-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 36px 28px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.service-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--red), var(--blue-accent));
  opacity: 0;
  transition: opacity var(--transition);
}

.service-card:hover {
  border-color: var(--blue-accent);
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
  background: var(--bg-surface);
}

.service-card:hover::before {
  opacity: 1;
}

.service-card:active {
  border-color: var(--blue-accent);
  background: var(--bg-surface);
}

.service-card:active::before {
  opacity: 1;
}

.service-icon {
  width: 56px;
  height: 56px;
  border-radius: 12px;
  background: rgba(109, 206, 245, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--blue-accent);
}

.service-icon svg {
  width: 28px;
  height: 28px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.service-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.service-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.service-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.service-tag {
  font-size: 0.8rem;
  padding: 4px 10px;
  border-radius: 20px;
  background: rgba(109, 206, 245, 0.1);
  color: var(--blue-accent);
  border: 1px solid rgba(109, 206, 245, 0.2);
}

/* ============================================
   EXPERTISE
   ============================================ */
.expertise-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.expertise-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px 24px;
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: all var(--transition);
}

.expertise-item:hover {
  border-color: var(--red);
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(185, 19, 26, 0.15);
}

.expertise-icon {
  width: 44px;
  height: 44px;
  min-width: 44px;
  border-radius: 10px;
  background: rgba(185, 19, 26, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--red);
}

.expertise-icon svg {
  width: 22px;
  height: 22px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.expertise-info h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.expertise-info p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ============================================
   INDUSTRIES
   ============================================ */
.industries-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}

.industry-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 36px 20px;
  text-align: center;
  transition: all var(--transition);
}

.industry-card:hover {
  border-color: var(--blue-accent);
  transform: translateY(-6px);
  box-shadow: 0 10px 30px rgba(0, 68, 128, 0.2);
}

.industry-icon {
  width: 64px;
  height: 64px;
  border-radius: 16px;
  background: rgba(0, 68, 128, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  color: var(--blue-accent);
}

.industry-icon svg {
  width: 30px;
  height: 30px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.industry-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.industry-card p {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ============================================
   CONTACT
   ============================================ */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  max-width: 900px;
  margin: 0 auto;
}

.contact-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 36px 28px;
  text-align: center;
  transition: all var(--transition);
}

.contact-card:hover {
  border-color: var(--blue-accent);
  transform: translateY(-4px);
  box-shadow: 0 8px 25px rgba(109, 206, 245, 0.1);
}

.contact-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  background: rgba(109, 206, 245, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  color: var(--blue-accent);
}

.contact-icon svg {
  width: 26px;
  height: 26px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.contact-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.contact-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  overflow-wrap: break-word;
}

.contact-card a {
  color: var(--text-secondary);
  transition: color var(--transition);
  white-space: nowrap;
}

.contact-card a:hover {
  color: var(--blue-accent);
}

.contact-card a:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

/* Contact Map */
.contact-map {
  max-width: 900px;
  margin: 48px auto 0;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--border);
}

.contact-map iframe {
  display: block;
}

/* Contact Form */
.contact-form-wrapper {
  max-width: 700px;
  margin: 48px auto 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 40px 36px;
}

.contact-form-wrapper h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 24px;
  text-align: center;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.form-group input,
.form-group textarea {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 16px;
  font-size: 0.95rem;
  color: var(--text-primary);
  font-family: inherit;
  transition: border-color var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: 2px solid var(--blue-accent);
  outline-offset: 2px;
  border-color: var(--blue-accent);
}

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

.contact-form .btn {
  align-self: center;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  padding: 48px 0 24px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 40px;
}

.footer-brand {
  max-width: 320px;
}

.footer-logo {
  height: 36px;
  margin-bottom: 12px;
}

.footer-brand p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.footer-links h4 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: color var(--transition);
}

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

.footer-links a:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 20px;
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ============================================
   LANGUAGE TOGGLE CONTENT
   ============================================ */
[data-lang-en],
[data-lang-th] {
  transition: opacity 0.2s ease;
}

body[data-lang="th"] [data-lang-en] {
  display: none;
}

body:not([data-lang="th"]) [data-lang-th] {
  display: none;
}

/* ============================================
   ACCESSIBILITY
   ============================================ */

/* Forced colors (high-contrast mode) fallback */
@media (forced-colors: active) {
  .section-title h2,
  .hero-tagline {
    -webkit-text-fill-color: unset;
    background: none;
    color: CanvasText;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .fade-in {
    transition: opacity 0.3s ease;
    transform: none;
  }

  .fade-in.visible {
    transform: none;
  }

  .stat-card:hover,
  .service-card:hover,
  .expertise-item:hover,
  .industry-card:hover,
  .contact-card:hover {
    transform: none;
  }

  .btn-primary:hover,
  .btn-secondary:hover {
    transform: none;
  }
}

/* ============================================
   SKIP LINK
   ============================================ */
.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: 8px 16px;
  border-radius: 0 0 8px 8px;
  font-weight: 600;
  z-index: 9999;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 0;
}

/* ============================================
   SCROLL TO TOP
   ============================================ */
.scroll-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--red);
  color: white;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--transition), visibility var(--transition), transform var(--transition), background-color var(--transition);
  z-index: 900;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.scroll-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.scroll-to-top:hover {
  background: var(--red-dark);
}

.scroll-to-top:focus-visible {
  outline: 2px solid var(--blue-accent);
  outline-offset: 3px;
}

.scroll-to-top svg {
  width: 20px;
  height: 20px;
  stroke: currentColor;
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ============================================
   FORM VALIDATION
   ============================================ */
.form-group input:invalid:not(:placeholder-shown),
.form-group textarea:invalid:not(:placeholder-shown) {
  border-color: var(--red);
}

.form-group input:invalid:not(:placeholder-shown):focus,
.form-group textarea:invalid:not(:placeholder-shown):focus {
  outline-color: var(--red);
}

/* ============================================
   RESPONSIVE
   ============================================ */

/* Tablet */
@media (max-width: 1024px) {
  .hero-tagline {
    font-size: 2.5rem;
  }

  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .expertise-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .industries-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about-stats {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* Mobile */
@media (max-width: 768px) {
  :root {
    --section-padding: 60px 0;
  }

  .nav-links {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    height: 100dvh;
    background: rgba(10, 15, 28, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 32px;
    z-index: 998;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    font-size: 1.2rem;
  }

  .hamburger {
    display: flex;
    z-index: 999;
  }

  .lang-toggle {
    z-index: 999;
  }

  .hero-tagline {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .hero-logo {
    width: 280px;
  }

  .section-title h2 {
    font-size: 1.8rem;
  }

  .services-grid {
    grid-template-columns: 1fr;
  }

  .expertise-grid {
    grid-template-columns: 1fr;
  }

  .industries-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-stats {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-grid {
    grid-template-columns: 1fr;
  }

  .footer-content {
    flex-direction: column;
    gap: 32px;
  }

  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 280px;
    justify-content: center;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .contact-form-wrapper {
    padding: 28px 20px;
  }

  .contact-form .btn {
    align-self: stretch;
    max-width: none;
  }
}

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

  .industries-grid {
    grid-template-columns: 1fr;
  }
}