/* ==========================================
   SinhaVeli Labs - Design System
   Apple-inspired aesthetic with light/dark themes
   ========================================== */

/* Import Inter Font from Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

/* ==========================================
   CSS Custom Properties - Theme System
   ========================================== */

:root {
  /* Primary Brand Colors */
  --color-primary: #B91C1C;
  --color-primary-dark: #991B1B;
  --color-primary-light: #DC2626;

  /* Light Mode Colors */
  --color-bg-primary: #FFFFFF;
  --color-bg-secondary: #F9FAFB;
  --color-bg-tertiary: #F3F4F6;
  --color-text-primary: #1F2937;
  --color-text-secondary: #6B7280;
  --color-text-tertiary: #9CA3AF;
  --color-border: #E5E7EB;
  --color-shadow: rgba(0, 0, 0, 0.1);
  --color-overlay: rgba(0, 0, 0, 0.5);

  /* Typography */
  --font-family-base: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-weight-light: 300;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;
  --font-weight-black: 900;

  /* Font Sizes */
  --font-size-xs: 0.75rem;
  /* 12px */
  --font-size-sm: 0.875rem;
  /* 14px */
  --font-size-base: 1rem;
  /* 16px */
  --font-size-lg: 1.125rem;
  /* 18px */
  --font-size-xl: 1.25rem;
  /* 20px */
  --font-size-2xl: 1.5rem;
  /* 24px */
  --font-size-3xl: 1.875rem;
  /* 30px */
  --font-size-4xl: 2.25rem;
  /* 36px */
  --font-size-5xl: 3rem;
  /* 48px */
  --font-size-6xl: 3.75rem;
  /* 60px */
  --font-size-7xl: 4.5rem;
  /* 72px */

  /* Spacing Scale */
  --space-1: 0.25rem;
  /* 4px */
  --space-2: 0.5rem;
  /* 8px */
  --space-3: 0.75rem;
  /* 12px */
  --space-4: 1rem;
  /* 16px */
  --space-5: 1.25rem;
  /* 20px */
  --space-6: 1.5rem;
  /* 24px */
  --space-8: 2rem;
  /* 32px */
  --space-10: 2.5rem;
  /* 40px */
  --space-12: 3rem;
  /* 48px */
  --space-16: 4rem;
  /* 64px */
  --space-20: 5rem;
  /* 80px */
  --space-24: 6rem;
  /* 96px */
  --space-32: 8rem;
  /* 128px */

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);

  /* Border Radius */
  --radius-sm: 0.375rem;
  /* 6px */
  --radius-md: 0.5rem;
  /* 8px */
  --radius-lg: 0.75rem;
  /* 12px */
  --radius-xl: 1rem;
  /* 16px */
  --radius-2xl: 1.5rem;
  /* 24px */
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* Dark Mode Theme */
[data-theme="dark"] {
  --color-bg-primary: #0A0A0A;
  --color-bg-secondary: #1A1A1A;
  --color-bg-tertiary: #2A2A2A;
  --color-text-primary: #F9FAFB;
  --color-text-secondary: #D1D5DB;
  --color-text-tertiary: #9CA3AF;
  --color-border: #374151;
  --color-shadow: rgba(0, 0, 0, 0.3);
  --color-overlay: rgba(0, 0, 0, 0.7);
}

/* ==========================================
   Base Styles & Resets
   ========================================== */

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

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

body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-regular);
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  transition: background-color var(--transition-base), color var(--transition-base);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* ==========================================
   Typography
   ========================================== */

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: var(--font-weight-bold);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--color-text-primary);
}

h1 {
  font-size: var(--font-size-6xl);
  font-weight: var(--font-weight-extrabold);
}

h2 {
  font-size: var(--font-size-5xl);
  font-weight: var(--font-weight-bold);
}

h3 {
  font-size: var(--font-size-4xl);
}

h4 {
  font-size: var(--font-size-3xl);
}

h5 {
  font-size: var(--font-size-2xl);
}

h6 {
  font-size: var(--font-size-xl);
}

p {
  margin-bottom: var(--space-4);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-dark);
}

/* ==========================================
   Navigation
   ========================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-fixed);
  background-color: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  transition: all var(--transition-base);
}

[data-theme="dark"] .navbar {
  background-color: rgba(10, 10, 10, 0.8);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: var(--space-4) var(--space-6);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  height: 56px;
  transition: transform var(--transition-fast);
}

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

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--space-8);
  align-items: center;
  margin-left: auto;
}

.nav-link {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  position: relative;
}

.nav-link:hover {
  color: var(--color-primary);
  background-color: var(--color-bg-secondary);
}

.nav-link.active {
  color: var(--color-primary);
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: var(--space-4);
  right: var(--space-4);
  height: 2px;
  background-color: var(--color-primary);
  border-radius: var(--radius-full);
}

/* Theme Toggle Button */
.theme-toggle {
  background: none;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-full);
  width: 44px;
  height: 44px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  margin-left: var(--space-6);
}

.theme-toggle:hover {
  border-color: var(--color-primary);
  background-color: var(--color-bg-secondary);
  transform: rotate(15deg) scale(1.05);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: var(--font-size-2xl);
  color: var(--color-text-primary);
  cursor: pointer;
  padding: var(--space-2);
}

/* ==========================================
   Hero Section
   ========================================== */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--space-20) var(--space-6);
  background: linear-gradient(135deg, var(--color-bg-primary) 0%, var(--color-bg-secondary) 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 30% 50%, rgba(185, 28, 28, 0.1) 0%, transparent 50%);
  opacity: 0.5;
}

.hero-content {
  max-width: 900px;
  position: relative;
  z-index: 1;
}

.hero-title {
  font-size: var(--font-size-7xl);
  font-weight: var(--font-weight-black);
  margin-bottom: var(--space-6);
  background: linear-gradient(135deg, var(--color-text-primary) 0%, var(--color-text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: fadeInUp 0.8s ease-out;
}

.hero-subtitle {
  font-size: var(--font-size-2xl);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-10);
  font-weight: var(--font-weight-regular);
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-cta {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

/* ==========================================
   Buttons
   ========================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-4) var(--space-8);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-xl);
  border: none;
  cursor: pointer;
  transition: all var(--transition-base);
  font-family: var(--font-family-base);
  text-decoration: none;
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
  box-shadow: var(--shadow-lg);
}

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

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

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

/* ==========================================
   Sections
   ========================================== */

section {
  padding: var(--space-20) var(--space-6);
  position: relative;
  scroll-margin-top: 100px;
}

.section-container {
  max-width: 1280px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section-title {
  font-size: var(--font-size-5xl);
  margin-bottom: var(--space-4);
}

.section-subtitle {
  font-size: var(--font-size-xl);
  color: var(--color-text-secondary);
  max-width: 700px;
  margin: 0 auto;
}

/* ==========================================
   Services Section
   ========================================== */

.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-8);
  margin-top: var(--space-12);
}

.service-card {
  padding: var(--space-8);
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-2xl);
  border: 1px solid var(--color-border);
  transition: all var(--transition-base);
  cursor: pointer;
}

.service-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-2xl);
  border-color: var(--color-primary);
}

.service-icon {
  font-size: var(--font-size-5xl);
  margin-bottom: var(--space-4);
}

.service-title {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--space-3);
}

.service-description {
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ==========================================
   Technologies Section
   ========================================== */

.tech-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-6);
  margin-top: var(--space-12);
}

.tech-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-6);
  background-color: var(--color-bg-secondary);
  border-radius: var(--radius-xl);
  transition: all var(--transition-fast);
  border: 1px solid var(--color-border);
}

.tech-item:hover {
  transform: scale(1.05);
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
}

.tech-icon {
  font-size: var(--font-size-4xl);
  margin-bottom: var(--space-3);
}

.tech-logo-img {
  width: 64px;
  height: 64px;
  object-fit: contain;
  margin-bottom: var(--space-3);
  transition: transform var(--transition-fast);
}

.tech-item:hover .tech-logo-img {
  transform: scale(1.1);
}

.tech-name {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
}

/* ==========================================
   Contact Section
   ========================================== */

.contact-content {
  max-width: 600px;
  margin: 0 auto;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form-label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
}

.form-input,
.form-textarea {
  padding: var(--space-4);
  font-size: var(--font-size-base);
  font-family: var(--font-family-base);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-lg);
  background-color: var(--color-bg-secondary);
  color: var(--color-text-primary);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(185, 28, 28, 0.1);
}

.form-textarea {
  min-height: 150px;
  resize: vertical;
}

/* ==========================================
   Footer
   ========================================== */

.footer {
  background-color: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
  padding: var(--space-16) var(--space-6) var(--space-8);
}

.footer-content {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.footer-section h4 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--space-4);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-link {
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--color-primary);
}

.footer-bottom {
  max-width: 1280px;
  margin: 0 auto;
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
  text-align: center;
  color: var(--color-text-tertiary);
  font-size: var(--font-size-sm);
}

/* ==========================================
   Animations
   ========================================== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

.fade-in {
  opacity: 0;
  animation: fadeIn 0.8s ease-out forwards;
}

.fade-in-up {
  opacity: 0;
  animation: fadeInUp 0.8s ease-out forwards;
}

/* Scroll Animation Classes */
.scroll-animate {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.scroll-animate.active {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================
   Starry Sky Background Effect
   ========================================== */

.shooting-stars-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

/* Static Stars */
.star {
  position: absolute;
  background: rgba(100, 100, 100, 0.6);
  border-radius: 50%;
  animation: twinkle var(--twinkle-duration) ease-in-out infinite;
  animation-delay: var(--twinkle-delay);
}

/* Different star sizes */
.star.small {
  width: 1px;
  height: 1px;
}

.star.medium {
  width: 2px;
  height: 2px;
}

.star.large {
  width: 3px;
  height: 3px;
  box-shadow: 0 0 2px rgba(100, 100, 100, 0.5);
}

/* Dark mode - brighter stars */
[data-theme="dark"] .star {
  background: rgba(255, 255, 255, 0.8);
}

[data-theme="dark"] .star.large {
  box-shadow: 0 0 3px rgba(255, 255, 255, 0.6);
}

/* Twinkling animation */
@keyframes twinkle {

  0%,
  100% {
    opacity: 0.3;
  }

  50% {
    opacity: 1;
  }
}

/* Shooting Stars */
.shooting-star {
  position: absolute;
  width: 2px;
  height: 2px;
  background: linear-gradient(90deg, rgba(185, 28, 28, 0.8), transparent);
  border-radius: 50%;
  filter: blur(0.5px);
  animation: shootingStar linear forwards;
  opacity: 0;
}

/* Light mode - darker, more subtle shooting stars */
.shooting-star::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 100px;
  height: 2px;
  background: linear-gradient(90deg, rgba(185, 28, 28, 0.6), rgba(185, 28, 28, 0.3), transparent);
}

/* Dark mode - brighter, more visible shooting stars */
[data-theme="dark"] .shooting-star {
  background: linear-gradient(90deg, rgba(255, 255, 255, 0.9), transparent);
  filter: blur(0.5px);
  box-shadow: 0 0 4px rgba(255, 255, 255, 0.5);
}

[data-theme="dark"] .shooting-star::before {
  background: linear-gradient(90deg, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0.4), transparent);
}

@keyframes shootingStar {
  0% {
    opacity: 0;
    transform: translate(0, 0) rotate(-45deg);
  }

  5% {
    opacity: 1;
  }

  50% {
    opacity: 1;
  }

  100% {
    opacity: 0;
    transform: translate(var(--shooting-distance-x), var(--shooting-distance-y)) rotate(-45deg);
  }
}

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

@media (max-width: 1024px) {
  :root {
    --font-size-7xl: 3.5rem;
    --font-size-6xl: 3rem;
    --font-size-5xl: 2.5rem;
  }

  .hero {
    padding: var(--space-16) var(--space-6);
  }
}

@media (max-width: 768px) {
  :root {
    --font-size-7xl: 2.5rem;
    --font-size-6xl: 2rem;
    --font-size-5xl: 1.75rem;
  }

  .theme-toggle {
    margin-left: auto;
    margin-right: var(--space-4);
  }

  .nav-menu {
    position: fixed;
    top: 73px;
    left: -100%;
    flex-direction: column;
    background-color: var(--color-bg-primary);
    width: 100%;
    padding: var(--space-8);
    box-shadow: var(--shadow-xl);
    transition: left var(--transition-base);
    align-items: flex-start;
  }

  .nav-menu.active {
    left: 0;
  }

  .mobile-menu-toggle {
    display: block;
  }

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

  .btn {
    width: 100%;
  }

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

  .tech-grid {
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  }
}

@media (max-width: 480px) {
  .nav-container {
    padding: var(--space-3) var(--space-4);
  }

  .nav-logo {
    height: 44px;
  }

  .hero {
    min-height: 80vh;
    padding: var(--space-20) var(--space-4) var(--space-12);
  }

  .hero-title {
    font-size: 2rem !important;
    line-height: 1.1;
    margin-bottom: var(--space-4);
    /* Remove gradient effect on mobile for better visibility */
    background: none !important;
    -webkit-text-fill-color: var(--color-text-primary) !important;
    color: var(--color-text-primary) !important;
  }

  .hero-subtitle {
    font-size: var(--font-size-lg);
    margin-bottom: var(--space-6);
  }

  section {
    padding: var(--space-12) var(--space-4);
  }

  .section-title {
    font-size: 2rem;
  }

  .section-subtitle {
    font-size: var(--font-size-base);
  }

  .tech-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-4);
  }

  .service-card {
    padding: var(--space-6);
  }

  .service-title {
    font-size: var(--font-size-xl);
  }
}