/* ===== Modern Professional CSS ===== */

:root {
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --primary-light: #3b82f6;
  --accent: #06b6d4;
  --accent-dark: #0891b2;
  --text: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --bg: #f8fafc;
  --card: #ffffff;
  --border: #e2e8f0;
  --success: #10b981;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --radius: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
}

/* ===== Global Reset ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 72px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 40px;
  transition: var(--transition);
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
  background: rgba(255, 255, 255, 0.95);
}

.site-header h1 {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
}

.site-logo {
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  object-fit: cover;
  transition: var(--transition);
}

.site-logo:hover {
  transform: scale(1.05);
}

.brand-text {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 800;
  letter-spacing: -0.5px;
}

/* Social Icons */
.social-icons {
  display: flex;
  gap: 12px;
}

.social-icons a {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  border-radius: 50%;
  color: var(--text-secondary);
  transition: var(--transition);
  text-decoration: none;
  font-size: 18px;
}

.social-icons a:hover {
  background: var(--primary);
  color: white;
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

/* ===== Navigation Sidebar ===== */
.sidebar {
  position: fixed;
  top: 72px;
  left: 0;
  width: 280px;
  height: calc(100vh - 72px);
  background: white;
  border-right: 1px solid var(--border);
  padding: 24px 0;
  z-index: 900;
  transition: var(--transition);
  overflow-y: auto;
  box-shadow: var(--shadow);
}

.sidebar-header {
  padding: 0 24px 24px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}

.sidebar-header span {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.sidebar-arrow {
  margin-left: auto;
  color: var(--text-muted);
  transition: var(--transition);
}

.sidebar a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 24px;
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
  border-left: 3px solid transparent;
  margin: 4px 0;
}

.sidebar a:hover,
.sidebar a.active {
  background: linear-gradient(90deg, rgba(37, 99, 235, 0.05), transparent);
  color: var(--primary);
  border-left-color: var(--primary);
}

.sidebar a i {
  font-size: 20px;
  width: 24px;
}

/* Mobile Toggle */
.sidebar-toggle {
  position: fixed;
  top: 14px;
  left: 20px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1100;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
}

.sidebar-toggle:hover {
  background: var(--primary-dark);
  transform: scale(1.05);
}

.sidebar-toggle i {
  font-size: 20px;
}

/* Sidebar Overlay */
.sidebar-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: 850;
  opacity: 0;
  transition: opacity 0.3s;
}

.sidebar-overlay.active {
  display: block;
  opacity: 1;
}

/* ===== Main Content ===== */
.main-content {
  margin-left: 280px;
  margin-top: 72px;
  padding: 48px 40px;
  min-height: calc(100vh - 72px);
  transition: var(--transition);
}

/* ===== Sections ===== */
.section {
  background: white;
  padding: 48px;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
  margin-bottom: 32px;
  border: 1px solid var(--border);
}

.section h2 {
  font-size: 36px;
  font-weight: 800;
  color: var(--text);
  margin-bottom: 24px;
  position: relative;
  padding-bottom: 16px;
}

.section h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px;
}

.section p {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
  font-size: 16px;
}

/* Hero Section */
.hero-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: white;
  text-align: center;
  padding: 80px 48px;
  border-radius: var(--radius-xl);
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg width="60" height="60" xmlns="http://www.w3.org/2000/svg"><circle cx="30" cy="30" r="1.5" fill="white" opacity="0.1"/></svg>');
  animation: float 20s linear infinite;
}

@keyframes float {
  from { transform: translateY(0); }
  to { transform: translateY(-60px); }
}

.hero-section h2 {
  color: white;
  font-size: 48px;
  margin-bottom: 20px;
  position: relative;
}

.hero-section h2::after {
  display: none;
}

.hero-section p {
  color: rgba(255, 255, 255, 0.95);
  font-size: 18px;
  max-width: 600px;
  margin: 0 auto 32px;
  position: relative;
}

/* Scroll Sections */
.scroll-section {
  background: white;
  padding: 40px;
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.scroll-section:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.scroll-section h3 {
  font-size: 24px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.scroll-section h3::before {
  content: '';
  width: 4px;
  height: 24px;
  background: linear-gradient(180deg, var(--primary), var(--accent));
  border-radius: 2px;
}

.scroll-section p {
  color: var(--text-secondary);
  line-height: 1.7;
}

.placeholder-box {
  height: 200px;
  background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%);
  border-radius: var(--radius);
  margin-top: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-weight: 500;
  border: 2px dashed var(--border);
}

/* ===== Slider ===== */
.slider-container {
  position: relative;
  width: 100%;
  max-width: 900px;
  height: 500px;
  margin: 32px auto;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--bg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
}

.slider-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.6s ease;
}

.slider-slide.active {
  opacity: 1;
  z-index: 2;
}

#mainImage {
  width: 100%;
  height: 100%;
  object-fit: contain;
  padding: 20px;
  transition: transform 0.4s ease;
}

.slider-container:hover #mainImage {
  transform: scale(1.03);
}

/* Thumbnails */
.slider-thumbnails {
  max-width: 900px;
  margin: 24px auto 0;
  overflow: hidden;
  padding: 0 12px;
}

.slider-thumbnails-track {
  display: flex;
  gap: 12px;
  transition: transform 0.3s ease;
  padding-bottom: 12px;
}

.slider-thumbnails img {
  width: 100px;
  height: 75px;
  object-fit: cover;
  border-radius: var(--radius);
  cursor: pointer;
  border: 3px solid transparent;
  transition: var(--transition);
  flex-shrink: 0;
  opacity: 0.6;
}

.slider-thumbnails img:hover {
  opacity: 1;
  transform: scale(1.08);
  box-shadow: var(--shadow-md);
}

.slider-thumbnails img.active {
  opacity: 1;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

/* Slider Buttons */
.slider-buttons {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-top: 32px;
}

.slider-buttons button {
  padding: 14px 28px;
  border: none;
  border-radius: 50px;
  background: var(--primary);
  color: white;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: var(--transition);
  box-shadow: var(--shadow);
}

.slider-buttons button:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.slider-buttons button i {
  font-size: 14px;
}

/* Product Detail */
.product-detail {
  text-align: center;
  padding: 48px 32px;
  background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
  border-radius: var(--radius-lg);
  margin-top: 32px;
  border: 1px solid var(--border);
}

.detail-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 16px;
}

.detail-desc {
  color: var(--text-secondary);
  line-height: 1.8;
  max-width: 700px;
  margin: 0 auto;
  font-size: 16px;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  border: none;
  border-radius: 50px;
  font-weight: 600;
  font-size: 15px;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s;
}

.btn:hover::before {
  left: 100%;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

.btn-secondary {
  background: white;
  color: var(--primary);
  border: 2px solid var(--primary);
}

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

/* ===== Contact Form ===== */
.contact-section {
  max-width: 700px;
  margin: 0 auto;
}

.contact-section form {
  display: flex;
  flex-direction: column;
  gap: 24px;
  margin-top: 32px;
}

.contact-section label {
  display: block;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
  font-size: 15px;
}

.contact-section input,
.contact-section textarea {
  width: 100%;
  padding: 14px 18px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  font-size: 15px;
  font-family: inherit;
  transition: var(--transition);
  background: white;
  color: var(--text);
}

.contact-section input:focus,
.contact-section textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

.contact-section textarea {
  resize: vertical;
  min-height: 140px;
}

.btn-submit {
  align-self: flex-start;
  padding: 14px 32px;
}

#formMessage {
  padding: 16px 24px;
  border-radius: var(--radius);
  font-weight: 500;
  text-align: center;
  margin-top: 20px;
  display: none;
}

#formMessage.success {
  display: block;
  background: #d1fae5;
  color: #065f46;
  border: 2px solid #10b981;
}

/* ===== Footer ===== */
.footer-contact {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  padding: 48px 40px;
  border-radius: var(--radius-xl);
  text-align: center;
  margin-top: 48px;
  position: relative;
  overflow: hidden;
}

.footer-contact::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg width="60" height="60" xmlns="http://www.w3.org/2000/svg"><circle cx="30" cy="30" r="1.5" fill="white" opacity="0.1"/></svg>');
}

.footer-contact > * {
  position: relative;
}

.footer-contact h3 {
  font-size: 28px;
  margin-bottom: 24px;
  font-weight: 700;
}

.footer-contact p {
  color: rgba(255, 255, 255, 0.95);
  margin: 12px 0;
  font-size: 16px;
}

.footer-contact .btn {
  margin-top: 24px;
  background: white;
  color: var(--primary);
}

.footer-contact .btn:hover {
  background: rgba(255, 255, 255, 0.9);
  transform: translateY(-2px);
}

/* ===== Animations ===== */
.fade-in {
  animation: fadeIn 0.6s ease-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ===== Responsive Design ===== */

/* Tablet */
@media (max-width: 1024px) {
  .main-content {
    margin-left: 0;
    padding: 32px 24px;
  }

  .sidebar {
    transform: translateX(-100%);
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .sidebar-toggle {
    display: flex;
  }

  .section {
    padding: 32px;
  }

  .slider-container {
    height: 400px;
  }
}

/* Mobile */
@media (max-width: 768px) {
  .site-header {
    padding: 0 20px;
    height: 64px;
    justify-content: center;
  }

  .site-header h1 {
    font-size: 18px;
  }

  .site-logo {
    width: 40px;
    height: 40px;
  }

  .brand-text {
    font-size: 16px;
  }

  /* Hide social icons on mobile to prevent overlap */
  .social-icons {
    display: none;
  }

  .main-content {
    margin-top: 64px;
    padding: 24px 16px;
  }

  .section {
    padding: 24px 20px;
    border-radius: var(--radius-lg);
  }

  .section h2 {
    font-size: 28px;
  }

  .hero-section {
    padding: 48px 24px;
  }

  .hero-section h2 {
    font-size: 32px;
  }

  .hero-section p {
    font-size: 16px;
  }

  .scroll-section {
    padding: 24px 20px;
  }

  .scroll-section h3 {
    font-size: 20px;
  }

  .slider-container {
    height: 300px;
    margin: 24px auto;
  }

  .slider-thumbnails img {
    width: 70px;
    height: 55px;
  }

  .slider-buttons {
    flex-direction: column;
    gap: 12px;
  }

  .slider-buttons button {
    width: 100%;
    justify-content: center;
    padding: 12px 24px;
  }

  .product-detail {
    padding: 32px 20px;
  }

  .detail-title {
    font-size: 22px;
  }

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

  .btn-submit {
    width: 100%;
  }

  .footer-contact {
    padding: 32px 20px;
  }

  .footer-contact h3 {
    font-size: 24px;
  }
}

/* Small Mobile */
@media (max-width: 480px) {
  .site-header h1 {
    font-size: 16px;
  }

  .brand-text {
    display: none;
  }

  .section h2 {
    font-size: 24px;
  }

  .hero-section h2 {
    font-size: 28px;
  }

  .slider-container {
    height: 250px;
  }

  .slider-thumbnails img {
    width: 60px;
    height: 48px;
  }

  .placeholder-box {
    height: 150px;
  }
}

/* ===== Accessibility ===== */
:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}