/* ==============================================================================
   NUVINTI.COM — Sustainable Energy Technology Services Portal
   Design System & Modern CSS Variables
   ============================================================================== */

:root {
  /* Color Palette */
  --bg-dark: #070c14;
  --bg-card: #0e1726;
  --bg-card-hover: #132035;
  --bg-glass: rgba(14, 23, 38, 0.75);
  --bg-glass-light: rgba(255, 255, 255, 0.04);
  
  --primary: #10b981;
  --primary-light: #34d399;
  --primary-dark: #059669;
  --primary-glow: rgba(16, 185, 129, 0.25);
  
  --solar: #f59e0b;
  --solar-light: #fbbf24;
  --solar-glow: rgba(245, 158, 11, 0.25);
  
  --cyan: #06b6d4;
  --cyan-light: #22d3ee;
  --cyan-dark: #0891b2;
  --cyan-glow: rgba(6, 182, 212, 0.25);
  
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-active: rgba(16, 185, 129, 0.35);
  --border-cyan: rgba(6, 182, 212, 0.35);
  
  /* Gradients */
  --grad-primary: linear-gradient(135deg, #10b981 0%, #06b6d4 100%);
  --grad-solar: linear-gradient(135deg, #f59e0b 0%, #10b981 100%);
  --grad-hero: radial-gradient(circle at 50% 20%, rgba(6, 182, 212, 0.15), rgba(16, 185, 129, 0.12) 35%, rgba(7, 12, 20, 0) 70%);
  --grad-card: linear-gradient(180deg, rgba(30, 41, 59, 0.4) 0%, rgba(15, 23, 42, 0.7) 100%);
  
  /* Shadows & Effects */
  --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 20px 40px -15px rgba(6, 182, 212, 0.15);
  --shadow-primary: 0 10px 25px -5px rgba(16, 185, 129, 0.3);
  --shadow-cyan: 0 10px 25px -5px rgba(6, 182, 212, 0.3);
  
  /* Radius & Transitions */
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 9999px;
  
  --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* Selection */
::selection {
  background: var(--primary);
  color: #000;
}

/* Container */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Typography Helpers */
h1, h2, h3, h4, h5, h6 {
  color: #fff;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.gradient-text {
  background: linear-gradient(135deg, var(--cyan-light), var(--primary-light), var(--solar-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.gradient-solar {
  background: linear-gradient(135deg, var(--solar-light), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.gradient-cyan {
  background: linear-gradient(135deg, var(--cyan-light), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Top Announcement Banner */
.top-bar {
  background: rgba(14, 23, 38, 0.9);
  border-bottom: 1px solid var(--border-subtle);
  padding: 0.5rem 0;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.top-bar-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.top-bar-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background-color: var(--primary-light);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--primary);
  display: inline-block;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 6px rgba(16, 185, 129, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

/* Navigation Bar */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(7, 12, 20, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 78px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
}

.logo-icon {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--solar), var(--cyan-dark), var(--primary));
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 15px rgba(6, 182, 212, 0.3);
  transition: var(--transition);
}

.logo:hover .logo-icon {
  transform: scale(1.05) rotate(3deg);
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-size: 1.4rem;
  font-weight: 900;
  letter-spacing: -0.03em;
  color: #fff;
}

.logo-title span {
  color: var(--cyan-light);
}

.logo-tagline {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--primary-light);
}

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

.nav-links a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 600;
  transition: var(--transition);
  position: relative;
}

.nav-links a:hover, .nav-links a.active {
  color: #fff;
}

.nav-links a:hover::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--grad-primary);
  border-radius: 2px;
}

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

/* Language Dropdown */
.lang-selector {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 0.45rem 0.8rem;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  outline: none;
  transition: var(--transition);
}

.lang-selector:focus {
  border-color: var(--cyan-light);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.6rem;
  font-size: 0.9rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.btn-primary {
  background: var(--grad-primary);
  color: #051410;
  box-shadow: var(--shadow-primary);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px -5px rgba(16, 185, 129, 0.45);
}

.btn-solar {
  background: var(--grad-solar);
  color: #1e1302;
  box-shadow: 0 10px 25px -5px rgba(245, 158, 11, 0.35);
}

.btn-solar:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 30px -5px rgba(245, 158, 11, 0.5);
}

.btn-outline {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.2);
  color: #fff;
  transform: translateY(-2px);
}

.btn-sm {
  padding: 0.45rem 1rem;
  font-size: 0.8rem;
  border-radius: var(--radius-sm);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 24px;
  height: 18px;
  background: transparent;
  border: none;
  cursor: pointer;
}

.hamburger span {
  width: 100%;
  height: 2px;
  background-color: #fff;
  border-radius: 2px;
  transition: var(--transition);
}

/* Hero Section */
.hero {
  position: relative;
  padding: 5rem 0 6rem;
  background: var(--grad-hero);
  overflow: hidden;
}

.hero-glow-bg {
  position: absolute;
  top: 10%;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 450px;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.18) 0%, rgba(16, 185, 129, 0.12) 40%, transparent 70%);
  filter: blur(80px);
  z-index: 0;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 920px;
  margin: 0 auto;
}

.badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1.1rem;
  border-radius: var(--radius-full);
  background: rgba(6, 182, 212, 0.1);
  border: 1px solid rgba(6, 182, 212, 0.3);
  color: var(--cyan-light);
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 1.75rem;
}

.hero-title {
  font-size: 3.6rem;
  font-weight: 900;
  margin-bottom: 1.5rem;
  letter-spacing: -0.03em;
  line-height: 1.1;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 760px;
  margin: 0 auto 2.5rem;
  font-weight: 400;
}

.hero-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}

/* Hero Stats Bar */
.hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-top: 4rem;
  text-align: left;
}

.stat-item {
  background: var(--bg-glass);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-subtle);
  padding: 1.5rem;
  border-radius: var(--radius-md);
  transition: var(--transition);
}

.stat-item:hover {
  transform: translateY(-4px);
  border-color: var(--border-cyan);
  box-shadow: var(--shadow-md);
}

.stat-value {
  font-size: 2rem;
  font-weight: 900;
  color: #fff;
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
}

.stat-value small {
  font-size: 1rem;
  color: var(--primary-light);
  font-weight: 700;
}

.stat-label {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--cyan-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 0.25rem;
}

.stat-sub {
  font-size: 0.75rem;
  color: var(--text-dim);
  margin-top: 0.25rem;
}

/* Section Shared Styling */
.section {
  padding: 6rem 0;
  position: relative;
}

.section-alt {
  background: #090f1a;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.section-header {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 3.5rem;
}

.section-eyebrow {
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--primary-light);
  margin-bottom: 0.75rem;
  display: block;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 900;
  margin-bottom: 1rem;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
}

/* Ecosystem / Services Grid */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.service-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.service-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--grad-primary);
  opacity: 0;
  transition: var(--transition);
}

.service-card:hover {
  transform: translateY(-8px);
  border-color: rgba(16, 185, 129, 0.3);
  box-shadow: var(--shadow-lg);
}

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

.service-icon-wrap {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary-light);
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
}

.service-card.cyan .service-icon-wrap {
  background: rgba(6, 182, 212, 0.1);
  border-color: rgba(6, 182, 212, 0.2);
  color: var(--cyan-light);
}

.service-card.solar .service-icon-wrap {
  background: rgba(245, 158, 11, 0.1);
  border-color: rgba(245, 158, 11, 0.2);
  color: var(--solar-light);
}

.service-title {
  font-size: 1.3rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
}

.service-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.service-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag-pill {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.3rem 0.7rem;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-muted);
}

/* Karga Spotlight & Hardware Showcase */
.karga-spotlight-card {
  background: linear-gradient(135deg, #0f1c2e 0%, #0a1420 100%);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-lg);
  padding: 3.5rem;
  box-shadow: var(--shadow-lg);
}

.karga-split {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 3.5rem;
  align-items: center;
}

.karga-info {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.karga-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-full);
  background: rgba(6, 182, 212, 0.15);
  border: 1px solid rgba(6, 182, 212, 0.35);
  color: var(--cyan-light);
  font-size: 0.8rem;
  font-weight: 800;
  width: fit-content;
}

.karga-title {
  font-size: 2.4rem;
  font-weight: 900;
  line-height: 1.15;
}

.karga-text {
  font-size: 1rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.karga-features-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin: 0.5rem 0;
}

.karga-feat-item {
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid var(--border-subtle);
  padding: 0.85rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  color: #e2e8f0;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.karga-feat-item svg {
  color: var(--cyan-light);
  flex-shrink: 0;
}

.karga-hardware-box {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  text-align: center;
  position: relative;
}

.charger-img {
  width: 100%;
  max-width: 380px;
  height: auto;
  margin: 0 auto;
  display: block;
  border-radius: var(--radius-md);
  filter: drop-shadow(0 15px 25px rgba(0, 0, 0, 0.6));
  transition: var(--transition);
}

.charger-img:hover {
  transform: scale(1.03);
}

/* Contact Section */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 3.5rem;
}

.contact-info-list {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
  margin-top: 2rem;
}

.contact-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.contact-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary-light);
  flex-shrink: 0;
}

.contact-item h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.contact-item p {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* Form Styles */
.contact-form {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
}

.form-group {
  margin-bottom: 1.25rem;
}

.form-label {
  display: block;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.form-control {
  width: 100%;
  background: rgba(7, 12, 20, 0.75);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.85rem 1rem;
  color: #fff;
  font-size: 0.9rem;
  font-family: inherit;
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--cyan-light);
  box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.15);
}

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

/* Notification Box */
.form-feedback {
  display: none;
  padding: 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 600;
  text-align: center;
  margin-top: 1rem;
}

.form-feedback.success {
  display: block;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.4);
  color: var(--primary-light);
}

/* Footer */
.footer {
  background: #04080e;
  border-top: 1px solid var(--border-subtle);
  padding: 4.5rem 0 2rem;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3.5rem;
}

.footer-col h4 {
  font-size: 0.95rem;
  font-weight: 800;
  color: #fff;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-col a {
  color: var(--text-muted);
  text-decoration: none;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--primary-light);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 2rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.8rem;
  color: var(--text-dim);
  flex-wrap: wrap;
  gap: 1rem;
}

/* Responsive Media Queries */
@media (max-width: 1024px) {
  .hero-title { font-size: 2.8rem; }
  .services-grid { grid-template-columns: 1fr 1fr; }
  .solar-showcase-grid { grid-template-columns: 1fr 1fr; }
  .hero-stats-grid { grid-template-columns: 1fr 1fr; }
  .karga-split { grid-template-columns: 1fr; }
  .calc-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .hamburger { display: flex; }
  .nav-links {
    position: fixed;
    top: 78px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 78px);
    background: rgba(7, 12, 20, 0.98);
    flex-direction: column;
    padding: 3rem 2rem;
    gap: 1.75rem;
    transition: var(--transition);
    border-top: 1px solid var(--border-subtle);
  }
  .nav-links.active { left: 0; }
  .hero-title { font-size: 2.2rem; }
  .hero-subtitle { font-size: 1rem; }
  .services-grid { grid-template-columns: 1fr; }
  .solar-showcase-grid { grid-template-columns: 1fr; }
  .hero-stats-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
}