/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  color: #000000;
  background: radial-gradient(circle at center, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #feca57);
  background-size: 400% 400%;
  animation: gradientShift 8s ease infinite;
  min-height: 100vh;
  scroll-behavior: smooth;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.container {
  max-width: 1200px;
  margin: auto;
  padding: 20px;
}

/* Navigation Bar */
nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(0, 0, 0, 0.7);
  padding: 15px 30px;
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
}

nav .logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: #000000;
}

nav a {
  color: #000000;
  margin-left: 20px;
  text-decoration: none;
  transition: color 0.3s;
  font-weight: 500;
}

nav a:hover {
  color: #00ffd5;
}

/* Section Styles */
section, header {
  padding: 60px 20px;
}

header {
  text-align: center;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  margin-top: 20px;
  backdrop-filter: blur(10px);
}

.section-title {
  font-size: 2rem;
  margin-bottom: 20px;
  text-align: center;
  color: #000000;
  text-shadow: 2px 2px 8px rgba(255, 255, 255, 0.5);
  font-weight: 600;
}

/* Grid Layouts */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
}

/* Portfolio Items */
.portfolio-item {
  background: rgba(255, 255, 255, 0.15);
  padding: 20px;
  border-radius: 10px;
  transition: transform 0.3s ease, background 0.3s ease;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.portfolio-item:hover {
  transform: translateY(-5px);
  background: rgba(255, 255, 255, 0.25);
}

/* Forms */
form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

input, textarea {
  padding: 12px;
  border: none;
  border-radius: 8px;
  font-size: 16px;
  width: 100%;
  background: rgba(255, 255, 255, 0.8);
  color: #000000;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

input::placeholder, textarea::placeholder {
  color: #666666;
  opacity: 0.9;
}

button {
  padding: 12px;
  font-size: 16px;
  background: linear-gradient(45deg, #00ffd5, #00c6a1);
  color: #000000;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(0, 255, 213, 0.3);
  font-weight: 600;
}

button:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 255, 213, 0.4);
}

/* Back to Top Button */
#backToTop {
  position: fixed;
  bottom: 40px;
  right: 40px;
  display: none;
  background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
  color: #fff;
  border: none;
  border-radius: 50%;
  width: 60px;
  height: 60px;
  font-size: 24px;
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  z-index: 999;
  transition: all 0.3s ease;
}

#backToTop:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 25px rgba(0, 0, 0, 0.4);
}

/* Footer */
footer {
  text-align: center;
  padding: 30px 20px;
  background: rgba(255, 255, 255, 0.8);
  color: #000000;
  font-size: 14px;
  backdrop-filter: blur(10px);
}

/* Accessibility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Media Queries */
@media screen and (max-width: 768px) {
  nav {
    flex-direction: column;
    align-items: flex-start;
  }

  nav a {
    margin-left: 0;
    margin-top: 10px;
  }

  header h1 {
    font-size: 1.8rem;
  }
  
  #backToTop {
    width: 50px;
    height: 50px;
    font-size: 20px;
    bottom: 30px;
    right: 30px;
  }
}

@media screen and (max-width: 480px) {
  .section-title {
    font-size: 1.5rem;
  }

  .container {
    padding: 15px;
  }

  button {
    font-size: 14px;
  }

  input, textarea {
    font-size: 14px;
  }
  
  #backToTop {
    width: 45px;
    height: 45px;
    font-size: 18px;
    bottom: 20px;
    right: 20px;
  }
}