/* ==========================================
   Modern CSS with Dark Mode & Glassmorphism
   ========================================== */

/* === CSS Variables for Light Mode === */
:root {
  --primary-color: #667eea;
  --secondary-color: #764ba2;
  --accent-color: #f093fb;
  --bg-color: #f0f4f8;
  --card-bg: rgba(255, 255, 255, 0.7);
  --text-color: #2d3748;
  --text-secondary: #718096;
  --navbar-bg: rgba(102, 126, 234, 0.95);
  --shadow: rgba(0, 0, 0, 0.1);
  --shadow-lg: rgba(0, 0, 0, 0.15);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* === CSS Variables for Dark Mode === */
@media (prefers-color-scheme: dark) {
  :root {
    --primary-color: #9f7aea;
    --secondary-color: #b794f4;
    --accent-color: #d6bcfa;
    --bg-color: #1a202c;
    --card-bg: rgba(45, 55, 72, 0.7);
    --text-color: #e2e8f0;
    --text-secondary: #a0aec0;
    --navbar-bg: rgba(74, 85, 104, 0.95);
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-lg: rgba(0, 0, 0, 0.5);
  }
}

/* === Manual Dark Mode Override === */
body.dark-mode {
  --primary-color: #9f7aea;
  --secondary-color: #b794f4;
  --accent-color: #d6bcfa;
  --bg-color: #1a202c;
  --card-bg: rgba(45, 55, 72, 0.7);
  --text-color: #e2e8f0;
  --text-secondary: #a0aec0;
  --navbar-bg: rgba(74, 85, 104, 0.95);
  --shadow: rgba(0, 0, 0, 0.3);
  --shadow-lg: rgba(0, 0, 0, 0.5);
}

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

body {
  font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background: var(--bg-color);
  transition: var(--transition);
}

/* === Theme Toggle Button === */
.theme-toggle {
  margin-left: auto;
  position: relative;
  background: var(--card-bg);
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  width: 50px;
  height: 50px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  margin-right: 1rem;
}

.theme-toggle:hover {
  transform: scale(1.1) rotate(15deg);
  box-shadow: 0 5px 20px var(--shadow-lg);
}

.theme-toggle:active {
  transform: scale(0.95);
}

.theme-toggle svg {
  position: absolute;
  transition: var(--transition);
}

.sun-icon {
  opacity: 1;
  transform: rotate(0deg);
}

body.dark-mode .sun-icon {
  opacity: 0;
  transform: rotate(180deg);
}

.moon-icon {
  opacity: 0;
  transform: rotate(-180deg);
}

body.dark-mode .moon-icon {
  opacity: 1;
  transform: rotate(0deg);
}

/* === Navigation Styles === */
.navbar {
  background: var(--navbar-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: 0 4px 20px var(--shadow);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: var(--transition);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand h1 {
  color: white;
  font-size: 1.5rem;
  padding: 1rem 0;
  font-weight: 700;
  letter-spacing: -0.5px;
}

/* === Hamburger Menu === */
.hamburger {
  display: none;
  flex-direction: column;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  z-index: 1001;
}

.hamburger-line {
  width: 25px;
  height: 3px;
  background-color: white;
  margin: 3px 0;
  transition: var(--transition);
  border-radius: 3px;
}

/* === Navigation Menu === */
.nav-menu {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 0.5rem;
}

.nav-menu li {
  margin: 0;
}

.nav-menu a {
  display: block;
  color: white;
  text-decoration: none;
  padding: 0.75rem 1.5rem;
  border-radius: 10px;
  transition: var(--transition);
  font-weight: 500;
  background: rgba(255, 255, 255, 0.1);
}

.nav-menu a:hover,
.nav-menu a:focus {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
  box-shadow: 0 5px 15px var(--shadow);
}

/* === Main Content === */
main {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 20px;
}

/* === Glassmorphism Cards === */
.card,
section {
  background: var(--card-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  margin-bottom: 2rem;
  padding: 2.5rem;
  border-radius: 20px;
  box-shadow: 0 8px 32px var(--shadow);
  transition: var(--transition);
}

.card:hover,
section:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 40px var(--shadow-lg);
  border-color: rgba(255, 255, 255, 0.3);
}

h2 {
  color: var(--text-color);
  margin-bottom: 1.5rem;
  font-size: 2rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

p {
  color: var(--text-color);
  margin-bottom: 1rem;
  line-height: 1.8;
}

ul {
  margin-left: 2rem;
  color: var(--text-color);
}

li {
  margin-bottom: 0.75rem;
  position: relative;
  padding-left: 0.5rem;
}

li::before {
  content: '•';
  color: var(--primary-color);
  font-weight: bold;
  position: absolute;
  left: -1rem;
}

/* === Special Sections === */
#about {
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
}

#features {
  background: linear-gradient(135deg, rgba(240, 147, 251, 0.1), rgba(159, 122, 234, 0.1));
}

#demo {
  background: linear-gradient(135deg, rgba(118, 75, 162, 0.1), rgba(240, 147, 251, 0.1));
}

#contribute {
  background: linear-gradient(135deg, rgba(159, 122, 234, 0.1), rgba(102, 126, 234, 0.1));
}

/* === Footer === */
footer {
  background: var(--navbar-bg);
  backdrop-filter: blur(10px);
  color: white;
  text-align: center;
  padding: 2rem;
  margin-top: 3rem;
  border-radius: 20px 20px 0 0;
}

footer p {
  color: white;
  margin: 0;
}

/* === Responsive Design === */
@media screen and (max-width: 768px) {
  .hamburger {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    top: 0;
    right: -100%;
    height: 100vh;
    width: 70%;
    max-width: 300px;
    flex-direction: column;
    background: var(--navbar-bg);
    backdrop-filter: blur(20px);
    padding-top: 4rem;
    transition: right 0.3s ease;
    box-shadow: -5px 0 20px var(--shadow-lg);
    gap: 0;
  }

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

  .nav-menu li {
    width: 100%;
  }

  .nav-menu a {
    padding: 1.2rem 2rem;
    width: 100%;
    border-radius: 0;
  }

  .hamburger.active .hamburger-line:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
  }

  .hamburger.active .hamburger-line:nth-child(2) {
    opacity: 0;
  }

  .hamburger.active .hamburger-line:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
  }

  .nav-brand h1 {
    font-size: 1.2rem;
  }

  .card,
  section {
    padding: 1.5rem;
  }

  h2 {
    font-size: 1.5rem;
  }
}

@media screen and (max-width: 480px) {
  .nav-brand h1 {
    font-size: 1rem;
  }

  .theme-toggle {
    width: 40px;
    height: 40px;
  }

  .card,
  section {
    padding: 1rem;
    border-radius: 15px;
  }

  main {
    padding: 0 15px;
  }
}

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

.card,
section {
  animation: fadeIn 0.6s ease-out;
}

/* === Accessibility === */
.nav-menu a:focus-visible,
.theme-toggle:focus-visible,
.hamburger:focus-visible {
  outline: 3px solid var(--accent-color);
  outline-offset: 2px;
}

/* === Smooth Scrolling === */
html {
  scroll-behavior: smooth;
}