/* ===================================
   OnlyCampus - Landing Page
   Main Stylesheet
   =================================== */

/* =============================
   CSS Variables & Theme
   ============================= */
:root {
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', sans-serif;
  --font-secondary: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Color Palette - Same as SolarityAI */
  --color-dark-bg: #0f172a;
  --color-dark-secondary: #1e293b;
  --color-dark-tertiary: #334155;

  --color-primary: #1e40af;
  --color-primary-dark: #1e3a8a;
  --color-primary-light: #3b82f6;

  --color-secondary: #059669;
  --color-secondary-dark: #047857;

  --color-purple: #7c3aed;
  --color-purple-dark: #6b21a8;

  --color-orange: #c2410c;
  --color-orange-dark: #9a3412;

  --color-teal: #0d9488;
  --color-teal-dark: #0f766e;

  --color-white: #ffffff;
  --color-text-primary: #f8fafc;
  --color-text-secondary: #cbd5e1;
  --color-text-tertiary: #94a3b8;

  /* Gradients */
  --gradient-blue: linear-gradient(135deg, #1e40af 0%, #1e3a8a 100%);
  --gradient-green: linear-gradient(135deg, #059669 0%, #047857 100%);
  --gradient-purple: linear-gradient(135deg, #7c3aed 0%, #6b21a8 100%);
  --gradient-orange: linear-gradient(135deg, #c2410c 0%, #9a3412 100%);
  --gradient-teal: linear-gradient(135deg, #0d9488 0%, #0f766e 100%);

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 3rem;
  --spacing-xl: 4rem;

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.2);
  --shadow-xl: 0 12px 40px rgba(0, 0, 0, 0.25);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  font-weight: 400;
  color: var(--color-text-secondary);
  background-color: var(--color-dark-bg);
  background-image:
    radial-gradient(at 0% 0%, rgba(30, 64, 175, 0.05) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(124, 58, 237, 0.05) 0px, transparent 50%);
  background-attachment: fixed;
  line-height: 1.7;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "kern" 1, "liga" 1;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-secondary);
  font-weight: 600;
  color: var(--color-text-primary);
  line-height: 1.3;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
  font-feature-settings: "kern" 1, "liga" 1;
}

h1 {
  font-size: 3.5rem;
}

h2 {
  font-size: 2.5rem;
}

h3 {
  font-size: 2rem;
}

h4 {
  font-size: 1.5rem;
}

h5 {
  font-size: 1.25rem;
}

h6 {
  font-size: 1rem;
}

p {
  font-size: 1.125rem;
  line-height: 1.8;
  margin-bottom: 1rem;
}

a {
  text-decoration: none;
  color: inherit;
  transition: all var(--transition-base);
}

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

.text-gradient {
  background: var(--gradient-blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* =============================
   Header & Navigation
   ============================= */
.ud-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(20px);
  transition: all var(--transition-base);
  padding: 1rem 0;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2), 0 2px 8px rgba(0, 0, 0, 0.1);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.ud-header.sticky {
  background: rgba(15, 23, 42, 0.95);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3), 0 4px 16px rgba(0, 0, 0, 0.2);
  padding: 0.75rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.navbar {
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  position: relative;
}

.navbar-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-text-primary);
  font-family: var(--font-secondary);
}

.logo-text {
  background: var(--gradient-blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.navbar-collapse {
  flex-grow: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
}

.navbar-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin: 0 auto;
  width: 100%;
}

.navbar-nav .nav-item {
  padding: 0;
  margin: 0;
  display: flex;
  align-items: center;
}

.navbar-nav .nav-item>a,
.navbar-nav .nav-item>.nav-link {
  color: var(--color-text-primary);
  font-weight: 500;
  font-size: 1rem;
  padding: 0.5rem 1.25rem;
  position: relative;
  transition: all var(--transition-base);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
  display: block;
  white-space: nowrap;
  text-align: center;
}

.navbar-nav .nav-item>a::after,
.navbar-nav .nav-item>.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-blue);
  transition: width var(--transition-base);
  box-shadow: 0 2px 8px rgba(30, 64, 175, 0.4);
}

.navbar-nav .nav-item>a:hover::after,
.navbar-nav .nav-item>a.active::after,
.navbar-nav .nav-item>.nav-link:hover::after,
.navbar-nav .nav-item>.nav-link.active::after {
  width: 100%;
}

.navbar-nav .nav-item>a:hover,
.navbar-nav .nav-item>a.active,
.navbar-nav .nav-item>.nav-link:hover,
.navbar-nav .nav-item>.nav-link.active {
  color: var(--color-primary-light);
  text-shadow: 0 2px 4px rgba(59, 130, 246, 0.3);
}


.navbar-toggler {
  border: none;
  padding: 0.5rem;
  position: relative;
  z-index: 1001;
  background: transparent;
  cursor: pointer;
  outline: none;
  -webkit-tap-highlight-color: transparent;
  pointer-events: auto !important;
}

.navbar-toggler .toggler-icon {
  width: 25px;
  height: 2px;
  background: var(--color-text-primary);
  display: block;
  margin: 5px 0;
  transition: all var(--transition-base);
}

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

.navbar-toggler.active .toggler-icon:nth-child(2) {
  opacity: 0;
}

.navbar-toggler.active .toggler-icon:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

@media (max-width: 991px) {
  .navbar {
    justify-content: space-between;
  }

  .navbar-collapse {
    background: var(--color-dark-secondary);
    margin-top: 1rem;
    padding: 0;
    border-radius: 8px;
    flex-grow: 0;
    display: none !important;
    width: 100%;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease, opacity 0.3s ease;
    opacity: 0;
  }

  .navbar-collapse.show {
    display: flex !important;
    max-height: 500px !important;
    padding: 1rem !important;
    width: 100% !important;
    opacity: 1 !important;
    visibility: visible !important;
  }

  .navbar-nav {
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
  }

  .navbar-nav .nav-item {
    padding: 0.5rem 0;
    width: 100%;
  }

}

/* =============================
   Hero Section
   ============================= */
.ud-hero {
  padding: 10rem 0 6rem;
  background: var(--color-dark-bg);
  position: relative;
  overflow: hidden;
}

.ud-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.3), transparent);
}

.ud-hero-content {
  position: relative;
  z-index: 1;
}

.ud-hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1.5rem;
  color: var(--color-text-primary);
}

.ud-hero-description {
  font-size: 1.25rem;
  color: var(--color-text-secondary);
  margin-bottom: 2rem;
  line-height: 1.8;
}

.ud-hero-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.ud-hero-image {
  position: relative;
  z-index: 1;
}

.phone-mockup {
  position: relative;
  max-width: 300px;
  margin: 0 auto;
  aspect-ratio: 9/16;
  background: var(--color-dark-secondary);
  border-radius: 30px;
  padding: 10px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.phone-screen {
  width: 100%;
  height: 100%;
  background: var(--color-dark-bg);
  border-radius: 25px;
  overflow: hidden;
  position: relative;
}

.app-preview {
  width: 100%;
  height: 100%;
  background: var(--color-dark-bg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  position: relative;
}

.app-header {
  background: var(--color-dark-secondary);
  padding: 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.app-status-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.35rem 1rem 0.25rem;
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.85);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.status-icons {
  display: flex;
  gap: 0.3rem;
  align-items: center;
}

.status-icons span {
  width: 0.4rem;
  height: 0.4rem;
  background: rgba(255, 255, 255, 0.7);
  border-radius: 50%;
}

.status-icons span:nth-child(2) {
  width: 0.5rem;
  height: 0.25rem;
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.6);
}

.status-icons span:nth-child(3) {
  width: 0.6rem;
  height: 0.3rem;
  border-radius: 3px;
  background: rgba(255, 255, 255, 0.5);
}

.app-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.85rem 1rem;
}

.app-nav h3 {
  font-size: 1.1rem;
  margin: 0;
  color: var(--color-text-primary);
  font-weight: 700;
  letter-spacing: -0.01em;
  background: var(--gradient-blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-icon {
  width: 1.75rem;
  height: 1.75rem;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-base);
}

.nav-icon::before {
  content: '';
  width: 0.75rem;
  height: 0.75rem;
  background: rgba(255, 255, 255, 0.4);
  border-radius: 2px;
}

.app-content {
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: linear-gradient(to bottom, var(--color-dark-bg) 0%, rgba(30, 64, 175, 0.02) 100%);
}

.app-card {
  background: var(--color-dark-secondary);
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
  transition: all var(--transition-base);
}

.app-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.4);
  border-color: rgba(255, 255, 255, 0.12);
}

.card-header {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding: 1rem;
}

.avatar {
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-purple) 100%);
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(30, 64, 175, 0.4);
  border: 2px solid rgba(255, 255, 255, 0.1);
}

.card-info {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.card-title {
  height: 0.85rem;
  width: 65%;
  background: rgba(255, 255, 255, 0.35);
  border-radius: 6px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.card-subtitle {
  height: 0.6rem;
  width: 45%;
  background: rgba(255, 255, 255, 0.25);
  border-radius: 6px;
}

.card-image {
  width: 100%;
  height: 9rem;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-purple) 100%);
  opacity: 0.5;
  position: relative;
  overflow: hidden;
}

.card-image::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(59, 130, 246, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(124, 58, 237, 0.3) 0%, transparent 50%);
}

.card-footer {
  padding: 0.85rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-actions {
  display: flex;
  gap: 1.25rem;
  align-items: center;
}

.card-actions span {
  width: 1.6rem;
  height: 1.6rem;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 8px;
  transition: all var(--transition-base);
}

.card-actions span:first-child {
  background: rgba(255, 255, 255, 0.2);
}

.app-bottom-nav {
  display: flex;
  justify-content: space-around;
  align-items: center;
  padding: 0.5rem 0 0.75rem;
  background: var(--color-dark-secondary);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.2);
  min-height: 3.5rem;
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.25rem;
  padding: 0.4rem 0.5rem;
  border-radius: 10px;
  transition: all var(--transition-base);
  cursor: pointer;
  flex: 1;
  max-width: 4rem;
  color: rgba(255, 255, 255, 0.5);
}

.nav-item i {
  font-size: 1.1rem;
  transition: all var(--transition-base);
}

.nav-item span {
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  transition: all var(--transition-base);
}

.nav-item.active {
  color: var(--color-primary-light);
  background: rgba(30, 64, 175, 0.15);
}

.nav-item.active i {
  color: var(--color-primary-light);
  transform: scale(1.1);
}

.nav-item.active span {
  color: var(--color-primary-light);
  font-weight: 600;
}

.nav-item:hover:not(.active) {
  color: rgba(255, 255, 255, 0.7);
  background: rgba(255, 255, 255, 0.05);
}

/* =============================
   Section Styles
   ============================= */
section {
  padding: 6rem 0;
  position: relative;
}

.ud-section-title {
  max-width: 700px;
  margin: 0 auto 2.5rem;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.ud-section-title span {
  display: block;
  font-size: 1rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-primary-light);
  margin-bottom: 0.5rem;
  text-shadow: 0 2px 4px rgba(59, 130, 246, 0.3);
  font-family: var(--font-primary);
}

.ud-section-title h2 {
  font-size: 3rem;
  margin-bottom: 1rem;
  text-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
  letter-spacing: -0.02em;
}

.ud-section-title p {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  line-height: 1.8;
}

/* =============================
   Features Section
   ============================= */
.ud-features {
  background: var(--color-dark-secondary);
  padding: 6rem 0;
  position: relative;
}

.ud-features::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.3), transparent);
}

.ud-features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  max-width: 100%;
}

.ud-feature-card {
  background: var(--color-dark-bg);
  border-radius: 12px;
  padding: 2rem;
  transition: all var(--transition-base);
  border: 1px solid rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.2), 0 0 0 1px rgba(255, 255, 255, 0.05);
  transform: translateY(-8px);
  text-align: left;
}

.ud-feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-blue);
  transform: scaleX(1);
  transition: transform var(--transition-base);
}

.ud-feature-card[data-color="blue"]::before {
  background: var(--gradient-blue);
}

.ud-feature-card[data-color="green"]::before {
  background: var(--gradient-green);
}

.ud-feature-card[data-color="purple"]::before {
  background: var(--gradient-purple);
}

.ud-feature-card[data-color="orange"]::before {
  background: var(--gradient-orange);
}

.ud-feature-card[data-color="teal"]::before {
  background: var(--gradient-teal);
}

.ud-feature-icon {
  width: 60px;
  height: 60px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  font-size: 1.75rem;
  background: var(--gradient-blue);
  color: var(--color-white);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4), 0 2px 8px rgba(0, 0, 0, 0.3);
  transform: scale(1.1);
}

.ud-feature-icon i {
  display: inline-block;
  font-style: normal;
  font-variant: normal;
  text-rendering: auto;
  line-height: 1;
}

.ud-feature-card[data-color="blue"] .ud-feature-icon {
  background: var(--gradient-blue);
}

.ud-feature-card[data-color="green"] .ud-feature-icon {
  background: var(--gradient-green);
}

.ud-feature-card[data-color="purple"] .ud-feature-icon {
  background: var(--gradient-purple);
}

.ud-feature-card[data-color="orange"] .ud-feature-icon {
  background: var(--gradient-orange);
}

.ud-feature-card[data-color="teal"] .ud-feature-icon {
  background: var(--gradient-teal);
}

.ud-feature-card h4 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
  color: var(--color-text-primary);
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.4;
}

.ud-feature-card p {
  font-size: 0.9375rem;
  color: var(--color-text-tertiary);
  margin: 0;
  line-height: 1.6;
  letter-spacing: 0.01em;
}

/* =============================
   About Section
   ============================= */
.ud-about {
  padding: 6rem 0;
  background: var(--color-dark-bg);
  position: relative;
}

.ud-about::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.3), transparent);
}

.ud-about-content h3 {
  margin-bottom: 1.5rem;
}

.ud-about-text {
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--color-text-secondary);
  margin-bottom: 1.5rem;
}

.ud-about-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.ud-about-list li {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
  color: var(--color-text-secondary);
  font-size: 1rem;
}

.ud-about-list li i {
  color: var(--color-primary-light);
  font-size: 1.25rem;
}

.ud-about-image {
  position: relative;
}

.about-visual {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  align-items: center;
  justify-content: center;
  height: 100%;
}

.visual-card {
  width: 100%;
  min-height: 140px;
  border-radius: 12px;
  background: var(--gradient-blue);
  opacity: 0.9;
  padding: 1.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3), 0 2px 8px rgba(0, 0, 0, 0.2);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.visual-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: rgba(255, 255, 255, 0.3);
}

.visual-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.3);
  opacity: 1;
}

.visual-card[data-color="green"] {
  background: var(--gradient-green);
}

.visual-card[data-color="purple"] {
  background: var(--gradient-purple);
}

.visual-card-content {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  z-index: 1;
  width: 100%;
}

.visual-card-content i {
  font-size: 2rem;
  color: var(--color-white);
  margin-bottom: 0.25rem;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.visual-card-content h5 {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-white);
  margin: 0;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  letter-spacing: -0.01em;
}

.visual-card-content p {
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.9);
  margin: 0;
  line-height: 1.5;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

/* =============================
   Download Section
   ============================= */
.ud-download {
  background: var(--color-dark-secondary);
  padding: 6rem 0;
  position: relative;
}

.ud-download::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.3), transparent);
}

.ud-download-buttons {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.ud-download-btn {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 2rem;
  background: var(--color-dark-bg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  color: var(--color-text-primary);
  transition: all var(--transition-base);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3), 0 2px 8px rgba(0, 0, 0, 0.2);
  min-width: 200px;
}

.ud-download-btn i {
  font-size: 2rem;
  color: var(--color-primary-light);
}

.ud-download-btn div {
  display: flex;
  flex-direction: column;
  text-align: left;
}

.ud-download-btn span {
  font-size: 0.75rem;
  color: var(--color-text-tertiary);
}

.ud-download-btn strong {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text-primary);
}

.ud-download-btn:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(30, 64, 175, 0.4), 0 4px 12px rgba(0, 0, 0, 0.3);
  border-color: var(--color-primary-light);
}

/* =============================
   Contact Section
   ============================= */
.ud-contact {
  background: var(--color-dark-bg);
  padding: 6rem 0;
}

.ud-contact-info {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.ud-single-info {
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  background: var(--color-dark-secondary);
  border-radius: 12px;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.2), 0 0 0 1px rgba(255, 255, 255, 0.05);
  transform: translateY(-8px);
  position: relative;
  overflow: hidden;
}

.ud-single-info::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-blue);
  transform: scaleX(1);
  transition: transform var(--transition-base);
}

.ud-info-icon {
  width: 50px;
  height: 50px;
  border-radius: 12px;
  background: var(--gradient-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-white);
  font-size: 1.25rem;
  flex-shrink: 0;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4), 0 2px 8px rgba(0, 0, 0, 0.3);
  transform: scale(1.1);
}

.ud-info-meta h5 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
  font-weight: 600;
  letter-spacing: -0.01em;
  font-family: var(--font-secondary);
}

.ud-info-meta p {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  margin: 0;
  line-height: 1.6;
  letter-spacing: 0.01em;
}

.ud-info-meta a {
  color: var(--color-primary-light);
}

.ud-info-meta a:hover {
  color: var(--color-primary);
}

.ud-contact-form-wrapper {
  background: var(--color-dark-secondary);
  border-radius: 12px;
  padding: 2rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.2), 0 0 0 1px rgba(255, 255, 255, 0.05);
  transform: translateY(-8px);
}

.ud-contact-form-wrapper::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-blue);
  transform: scaleX(1);
  transition: transform var(--transition-base);
  z-index: 10;
}

.ud-contact-form-title {
  font-size: 1.375rem;
  margin-bottom: 2rem;
  color: var(--color-text-primary);
}

.ud-form-group {
  margin-bottom: 1.5rem;
}

.ud-form-group label {
  display: block;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-primary);
  margin-bottom: 0.5rem;
}

.ud-form-group label .required {
  color: var(--color-primary-light);
}

.ud-form-group input,
.ud-form-group textarea {
  width: 100%;
  padding: 0.875rem 1.25rem;
  background: var(--color-dark-bg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  color: var(--color-text-primary);
  font-size: 1rem;
  font-family: inherit;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3), 0 2px 4px rgba(0, 0, 0, 0.2), inset 0 1px 2px rgba(255, 255, 255, 0.05);
  transition: all var(--transition-base);
}

.ud-form-group input:focus,
.ud-form-group textarea:focus {
  outline: none;
  border-color: var(--color-primary-light);
  box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.2), 0 6px 20px rgba(30, 64, 175, 0.15), 0 2px 8px rgba(0, 0, 0, 0.3);
  transform: translateY(-1px);
}

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

.ud-main-btn {
  display: inline-block;
  padding: 1rem 2rem;
  background: var(--gradient-blue);
  color: var(--color-white);
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-base);
  text-align: center;
  width: 100%;
  box-shadow: 0 6px 20px rgba(30, 64, 175, 0.4), 0 2px 8px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.2);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
  position: relative;
  overflow: hidden;
}

.ud-main-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 ease;
}

.ud-main-btn:hover::before {
  left: 100%;
}

.ud-main-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(30, 64, 175, 0.5), 0 4px 12px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
  opacity: 0.95;
}

.ud-main-btn:active {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(30, 64, 175, 0.4), 0 2px 4px rgba(0, 0, 0, 0.3);
}

.ud-secondary-btn {
  display: inline-block;
  padding: 1rem 2rem;
  background: transparent;
  color: var(--color-text-primary);
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-base);
  text-align: center;
}

.ud-secondary-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--color-primary-light);
  color: var(--color-primary-light);
  transform: translateY(-3px);
}

/* =============================
   Footer
   ============================= */
.ud-footer {
  background: var(--color-dark-secondary);
  padding: 4rem 0 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.2);
  position: relative;
}

.ud-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.5), transparent);
}

.ud-footer-widgets {
  padding-bottom: 3rem;
}

.ud-footer-logo {
  display: inline-block;
  margin-bottom: 1.5rem;
}

.ud-widget-desc {
  color: var(--color-text-tertiary);
  font-size: 0.9375rem;
  line-height: 1.6;
  margin-bottom: 0;
}

.ud-widget-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 1.5rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  letter-spacing: 0.01em;
}

.ud-widget-links {
  list-style: none;
  padding: 0;
  margin: 0;
}

.ud-widget-links li {
  margin-bottom: 0.75rem;
}

.ud-widget-links li a {
  color: var(--color-text-tertiary);
  font-size: 0.9375rem;
  transition: all var(--transition-base);
  display: inline-block;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.ud-widget-links li a:hover {
  color: var(--color-primary-light);
  padding-left: 8px;
  text-shadow: 0 2px 4px rgba(59, 130, 246, 0.3);
  transform: translateX(2px);
}

.ud-footer-bottom {
  background: var(--color-dark-bg);
  padding: 1.5rem 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.2);
}

.ud-footer-bottom-right {
  color: var(--color-text-tertiary);
  font-size: 0.875rem;
  margin: 0;
}

/* =============================
   Back to Top
   ============================= */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  background: var(--gradient-blue);
  color: var(--color-white);
  border-radius: 50%;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 999;
  transition: all var(--transition-base);
  box-shadow: 0 8px 24px rgba(30, 64, 175, 0.4), 0 4px 12px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.1);
  cursor: pointer;
}

.back-to-top:hover {
  transform: translateY(-5px) scale(1.1);
  box-shadow: 0 12px 32px rgba(30, 64, 175, 0.5), 0 6px 16px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.back-to-top:active {
  transform: translateY(-2px) scale(1.05);
}

.back-to-top i {
  font-size: 1.25rem;
}

/* =============================
   Responsive Design
   ============================= */
@media (max-width: 1199px) {
  h1 {
    font-size: 3rem;
  }

  h2 {
    font-size: 2.25rem;
  }

  .ud-hero-title {
    font-size: 3rem;
  }

  .ud-section-title h2 {
    font-size: 2.75rem;
  }
}

@media (max-width: 991px) {
  section {
    padding: 4rem 0;
  }

  .ud-hero {
    padding: 8rem 0 4rem;
  }

  .ud-features-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 767px) {
  h1 {
    font-size: 2.5rem;
  }

  h2 {
    font-size: 2rem;
  }

  h3 {
    font-size: 1.75rem;
  }

  .ud-hero-title {
    font-size: 2.5rem;
  }

  .ud-section-title h2 {
    font-size: 2.5rem;
  }

  section {
    padding: 4rem 0;
  }

  .ud-hero {
    padding: 8rem 0 4rem;
  }

  .ud-features-grid {
    grid-template-columns: 1fr;
  }

  .ud-hero-buttons {
    flex-direction: column;
  }

  .ud-hero-buttons .ud-main-btn,
  .ud-hero-buttons .ud-secondary-btn {
    width: 100%;
  }

  .ud-download-buttons {
    flex-direction: column;
    align-items: stretch;
  }

  .ud-download-btn {
    width: 100%;
  }

  .back-to-top {
    bottom: 1.5rem;
    right: 1.5rem;
    width: 45px;
    height: 45px;
  }
}

@media (max-width: 575px) {
  .ud-section-title {
    margin-bottom: 3rem;
  }

  .ud-section-title h2 {
    font-size: 2.25rem;
  }

  .ud-feature-card {
    padding: 1.5rem;
  }
}