:root {
  /* Color Palette - Premium Industrial */
  --c-navy: #152740;
  --c-navy-light: #1f3b5e;
  --c-blue: #0084d1;
  --c-blue-hover: #006eb3;
  --c-white: #ffffff;
  --c-bg: #f8fafc;
  --c-text: #334155;
  --c-text-light: #64748b;
  --c-border: #e2e8f0;

  /* Fonts */
  --f-main: 'Inter', system-ui, -apple-system, sans-serif;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--f-main);
  background-color: var(--c-bg);
  color: var(--c-text);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Nav */
nav {
  position: fixed;
  top: 0;
  width: 100%;
  padding: 1rem 5%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 1000;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(0,0,0,0.05);
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

.logo-container {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-img {
  height: 40px;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links li a {
  text-decoration: none;
  color: var(--c-navy);
  font-weight: 600;
  font-size: 0.95rem;
  transition: color 0.3s ease;
  position: relative;
}

.nav-links li a::after {
  content: '';
  position: absolute;
  width: 0%;
  height: 2px;
  bottom: -4px;
  left: 0;
  background-color: var(--c-blue);
  transition: width 0.3s ease;
}

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

.nav-links li a:hover {
  color: var(--c-blue);
}

.lang-switcher {
  display: flex;
  gap: 0.5rem;
}

.lang-switcher button {
  background: none;
  border: 1px solid var(--c-border);
  padding: 4px 8px;
  border-radius: 4px;
  cursor: pointer;
  font-family: var(--f-main);
  font-weight: 600;
  color: var(--c-text-light);
  transition: all 0.2s ease;
}

.lang-switcher button:hover,
.lang-switcher button.active {
  background-color: var(--c-navy);
  color: var(--c-white);
  border-color: var(--c-navy);
}

/* Sections */
section, header {
  padding: 7rem 5%;
}

/* Helper for visual blocks */
.img-fluid {
  max-width: 100%;
  height: auto;
  border-radius: 12px;
  box-shadow: 0 15px 30px rgba(0,0,0,0.1);
}

/* Header / Hero */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background-color: var(--c-navy);
  background-image: linear-gradient(to right, rgba(21, 39, 64, 0.95) 0%, rgba(21, 39, 64, 0.7) 100%), url('assets/images/pptx/image1.jpeg');
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  color: var(--c-white);
  position: relative;
}

.hero-content {
  max-width: 800px;
  z-index: 2;
}

.hero-content h1 {
  font-size: 4rem;
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  background: linear-gradient(to right, #ffffff, #a5c3e6);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-content p {
  font-size: 1.25rem;
  color: #e2e8f0;
  margin-bottom: 2.5rem;
  max-width: 650px;
}

.btn {
  display: inline-block;
  padding: 1rem 2.2rem;
  background-color: var(--c-blue);
  color: var(--c-white);
  font-weight: 600;
  text-decoration: none;
  border-radius: 6px;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  font-size: 1.05rem;
}

.btn:hover {
  background-color: var(--c-blue-hover);
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px rgba(0, 132, 209, 0.3);
}

/* Typography components */
.section-badge {
  display: inline-block;
  padding: 0.35rem 1rem;
  background-color: rgba(0, 132, 209, 0.1);
  color: var(--c-blue);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.section-title {
  font-size: 2.75rem;
  color: var(--c-navy);
  margin-bottom: 2.5rem;
  font-weight: 800;
  line-height: 1.2;
}

/* Problem Section */
#problem {
  background-color: var(--c-white);
}

.problem-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
  align-items: center;
}

.problem-text p {
  font-size: 1.15rem;
  margin-bottom: 1.5rem;
  color: var(--c-text);
}

.highlight-box {
  background-color: #f1f5f9;
  border-left: 4px solid var(--c-blue);
  padding: 2rem;
  font-weight: 700;
  font-size: 1.35rem;
  color: var(--c-navy);
  border-radius: 0 12px 12px 0;
  margin: 2.5rem 0;
}

.check-list {
  list-style: none;
}

.check-list li {
  position: relative;
  padding-left: 2.5rem;
  margin-bottom: 1.2rem;
  font-size: 1.15rem;
  font-weight: 600;
}

.check-list li::before {
  content: '\ebaa'; /* Boxicons bx-x or bx-error */
  font-family: 'boxicons';
  position: absolute;
  left: 0;
  top: 1px;
  color: #ef4444; 
  font-size: 1.4rem;
}

/* Solution Section */
#solution {
  background-color: var(--c-bg);
  position: relative;
}

.solution-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 4rem;
  align-items: center;
}

.features-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.feature-card {
  background: var(--c-white);
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 6px -1px rgba(0,0,0,0.05);
  transition: all 0.3s ease;
  border: 1px solid var(--c-border);
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
}

.feature-card:hover {
  transform: translateX(10px);
  border-color: var(--c-blue);
  box-shadow: 0 20px 25px -5px rgba(0, 132, 209, 0.1);
}

.feature-icon {
  font-size: 2.5rem;
  color: var(--c-blue);
  background: rgba(0,132,209,0.1);
  padding: 1rem;
  border-radius: 12px;
}

.feature-content h3 {
  font-size: 1.3rem;
  color: var(--c-navy);
  margin-bottom: 0.5rem;
}

/* GEDA Section */
#geda {
  background-image: linear-gradient(rgba(21, 39, 64, 0.9), rgba(21, 39, 64, 0.95)), url('assets/images/pptx/image6.png');
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  color: var(--c-white);
  text-align: center;
  padding: 8rem 5%;
}

#geda .section-title {
  color: var(--c-white);
}

#geda .section-badge {
  background-color: rgba(255,255,255,0.15);
  color: #a5c3e6;
}

#geda p {
  max-width: 800px;
  margin: 0 auto;
  font-size: 1.35rem;
  color: #e2e8f0;
}

/* Models Section */
#models {
  background-color: var(--c-white);
}

.models-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2.5rem;
  margin-top: 3rem;
}

.model-card {
  border: 1px solid var(--c-border);
  border-radius: 12px;
  overflow: hidden;
  transition: all 0.4s ease;
  background: #fff;
}

.model-card:hover {
  box-shadow: 0 20px 25px -5px rgba(0,0,0,0.1);
  transform: translateY(-8px);
  border-color: var(--c-blue);
}

.model-img {
  width: 100%;
  height: 240px;
  background-color: var(--c-white);
  background-size: contain;
  background-position: center;
  background-repeat: no-repeat;
  border-bottom: 1px solid var(--c-border);
  padding: 1rem;
}

.model-content {
  padding: 2rem;
}

.model-content h3 {
  color: var(--c-navy);
  margin-bottom: 0.75rem;
  font-size: 1.4rem;
}

.model-content p {
  color: var(--c-text-light);
  font-size: 1rem;
  line-height: 1.6;
}

/* References - Logo Ticker */
#references {
  background-color: var(--c-navy);
  text-align: center;
  color: var(--c-white);
  padding: 5rem 0;
  overflow: hidden;
}

#references .section-title {
  color: var(--c-white);
  margin-bottom: 3rem;
  padding: 0 5%;
}

.logo-ticker-wrapper {
  position: relative;
  overflow: hidden;
  width: 100%;
  /* Fade edges */
  mask-image: linear-gradient(to right, transparent 0%, black 8%, black 92%, transparent 100%);
  -webkit-mask-image: linear-gradient(to right, transparent 0%, black 8%, black 92%, transparent 100%);
}

.logo-ticker {
  display: flex;
  align-items: center;
  gap: 5rem;
  width: max-content;
  animation: ticker-scroll 22s linear infinite;
}

.logo-ticker:hover {
  animation-play-state: paused;
}

.ticker-item {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 60px;
  padding: 0 1rem;
}

.ticker-item img {
  height: 48px;
  width: auto;
  max-width: 180px;
  object-fit: contain;
  /* Render all logos in white/ghosted style for consistency */
  filter: brightness(0) invert(1);
  opacity: 0.7;
  transition: opacity 0.3s ease, filter 0.3s ease;
}

.ticker-item img:hover {
  opacity: 1;
  filter: brightness(0) invert(1) drop-shadow(0 0 8px rgba(255,255,255,0.5));
}

@keyframes ticker-scroll {
  0%   { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

/* Contact Section */
#contact {
  background-color: var(--c-white);
}

.contact-wrapper {
  max-width: 680px;
  margin: 0 auto;
  text-align: center;
}

.contact-desc {
  font-size: 1.25rem;
  margin-bottom: 3rem;
  color: var(--c-text-light);
}

.contact-email-card {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  background: var(--c-bg);
  border: 1px solid var(--c-border);
  border-radius: 16px;
  padding: 2rem 2.5rem;
  text-decoration: none;
  color: inherit;
  transition: all 0.3s ease;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.04);
}

.contact-email-card:hover {
  border-color: var(--c-blue);
  box-shadow: 0 0 0 4px rgba(0, 132, 209, 0.08), 0 8px 24px -4px rgba(0, 0, 0, 0.1);
  transform: translateY(-2px);
}

.contact-email-icon {
  flex-shrink: 0;
  width: 60px;
  height: 60px;
  background: var(--c-blue);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.contact-email-icon i {
  font-size: 1.75rem;
  color: #fff;
}

.contact-email-body {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.25rem;
  flex: 1;
}

.contact-email-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--c-text-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.contact-email-address {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--c-navy);
  letter-spacing: -0.01em;
}

.contact-email-arrow {
  font-size: 1.75rem;
  color: var(--c-blue);
  flex-shrink: 0;
  transition: transform 0.3s ease;
}

.contact-email-card:hover .contact-email-arrow {
  transform: translateX(4px);
}

/* Footer */
footer {
  background-color: var(--c-navy);
  color: rgba(255,255,255,0.5);
  text-align: center;
  padding: 2.5rem;
  border-top: 1px solid rgba(255,255,255,0.1);
}

/* Geda Stats */
.geda-stats {
  display: flex;
  justify-content: center;
  gap: 3rem;
  margin-top: 4rem;
  flex-wrap: wrap;
}

.geda-stat-box {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  padding: 2.5rem;
  border-radius: 12px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  min-width: 250px;
  transition: transform 0.4s ease, background 0.4s ease;
}

.geda-stat-box:hover {
  transform: translateY(-8px);
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.3);
}

.geda-stat-value {
  font-size: 3rem;
  font-weight: 800;
  color: var(--c-white);
  margin-bottom: 0.5rem;
  text-shadow: 0 4px 6px rgba(0,0,0,0.3);
}

.geda-stat-label {
  font-size: 1.15rem;
  color: #a5c3e6;
  font-weight: 600;
  letter-spacing: 0.5px;
}

/* Animations */
.fade-in-up {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

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

/* Responsive */
@media (max-width: 990px) {
  .problem-grid, .solution-grid {
    grid-template-columns: 1fr;
  }
  
  .hero-content h1 {
    font-size: 3.2rem;
  }
}

@media (max-width: 650px) {
  .nav-links {
    display: none;
  }
  .hero-content h1 {
    font-size: 2.5rem;
  }
  section, header {
    padding: 5rem 5%;
  }
}