:root {
  --primary: #9ca3af;
  /* Grey-400 */
  --primary-dark: #6b7280;
  --secondary: #d1d5db;
  /* Grey-300 */
  --accent: #e5e7eb;
  /* Grey-200 */
  --success: #10b981;
  --error: #ef4444;
  --bg-dark: #111827;
  /* Very Dark Grey (Inputs) */
  --bg-card: #1f2937;
  /* Dark Grey (Cards) */
  --bg-card-hover: #374151;
  /* Lighter Grey (Hover) */
  --text-primary: #f9fafb;
  /* White-ish */
  --text-secondary: #9ca3af;
  /* Grey */
  --border: #4b5563;
  /* Grey-600 */
  --shadow: rgba(0, 0, 0, 0.4);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
  /* Dark Grey Gradient */
  min-height: 100vh;
  color: var(--text-primary);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1rem;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

/* Landing Page Styles */
.landing-header {
  text-align: center;
  margin-bottom: 3rem;
  animation: fadeInDown 0.6s ease-out;
}

.landing-header h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  background: linear-gradient(135deg, #fff 0%, #9ca3af 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.landing-header p {
  font-size: 1.125rem;
  color: var(--text-secondary);
}

.auth-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: 0 20px 60px var(--shadow);
  border: 1px solid rgba(255, 255, 255, 0.1);
  width: 100%;
  max-width: 450px;
  animation: fadeInUp 0.6s ease-out;
}

.tabs {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid var(--border);
}

.tab {
  flex: 1;
  padding: 0.75rem;
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  position: relative;
}

.tab:hover {
  color: var(--text-primary);
}

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

.tab.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  animation: slideIn 0.3s ease-out;
}

.tab-content {
  display: none;
  animation: fadeIn 0.4s ease-out;
}

.tab-content.active {
  display: block;
}

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

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  font-weight: 500;
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.form-group input {
  width: 100%;
  padding: 0.875rem 1rem;
  background: var(--bg-dark);
  border: 2px solid var(--border);
  border-radius: 10px;
  color: var(--text-primary);
  font-size: 1rem;
  transition: all 0.3s ease;
}

.form-group input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.btn {
  width: 100%;
  padding: 1rem;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  border: none;
  border-radius: 10px;
  color: white;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}

.btn:active {
  transform: translateY(0);
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.message {
  padding: 1rem;
  border-radius: 10px;
  margin-bottom: 1.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  animation: slideDown 0.3s ease-out;
}

.message.success {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid var(--success);
  color: var(--success);
}

.message.error {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid var(--error);
  color: var(--error);
}

/* Portfolio Page Styles */
.portfolio-header {
  text-align: center;
  margin-bottom: 3rem;
  animation: fadeInDown 0.6s ease-out;
}

.portfolio-header h1 {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  background: linear-gradient(135deg, #fff 0%, #9ca3af 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.user-info {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border-radius: 15px;
  padding: 1.5rem;
  margin-bottom: 2rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  animation: fadeIn 0.6s ease-out;
}

.user-details h2 {
  font-size: 1.5rem;
  margin-bottom: 0.25rem;
}

.user-details p {
  color: var(--text-secondary);
}

.btn-logout {
  padding: 0.75rem 1.5rem;
  background: rgba(239, 68, 68, 0.2);
  border: 1px solid var(--error);
  border-radius: 10px;
  color: var(--error);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-logout:hover {
  background: var(--error);
  color: white;
  transform: translateY(-2px);
}

.portfolio-content {
  display: grid;
  gap: 2rem;
  animation: fadeInUp 0.6s ease-out;
}

.section-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border-radius: 20px;
  padding: 2rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all 0.3s ease;
}

.section-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 40px var(--shadow);
  border-color: rgba(102, 126, 234, 0.3);
}

.section-card h2 {
  font-size: 1.75rem;
  margin-bottom: 1rem;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-card h2::before {
  content: '';
  width: 4px;
  height: 1.5rem;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 2px;
}

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

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.skill-tag {
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.2) 0%, rgba(118, 75, 162, 0.2) 100%);
  padding: 0.75rem 1rem;
  border-radius: 10px;
  text-align: center;
  font-weight: 600;
  border: 1px solid rgba(102, 126, 234, 0.3);
  transition: all 0.3s ease;
}

.skill-tag:hover {
  border-color: var(--primary);
  transform: scale(1.05);
}

.projects-list {
  display: grid;
  gap: 1.5rem;
  margin-top: 1rem;
}

.project-item {
  background: rgba(17, 24, 39, 0.5);
  padding: 1.5rem;
  border-radius: 15px;
  border-left: 4px solid var(--primary);
  transition: all 0.3s ease;
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.project-item:hover {
  border-left-width: 8px;
  transform: translateX(5px);
}

.project-item h3 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.project-item p {
  margin-bottom: 0.5rem;
}

.project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}

.tech-badge {
  background: rgba(102, 126, 234, 0.2);
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  border: 1px solid rgba(102, 126, 234, 0.3);
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }

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

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }

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

@keyframes slideIn {
  from {
    transform: scaleX(0);
  }

  to {
    transform: scaleX(1);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }

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

/* Responsive Design */
@media (max-width: 768px) {
  .landing-header h1 {
    font-size: 2rem;
  }

  .auth-card {
    padding: 2rem 1.5rem;
  }

  .portfolio-header h1 {
    font-size: 2rem;
  }

  .user-info {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }

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

  .section-card {
    padding: 1.5rem;
  }
}

@media (max-width: 480px) {
  .landing-header h1 {
    font-size: 1.75rem;
  }

  .auth-card {
    padding: 1.5rem;
  }

  .tabs {
    gap: 0.5rem;
  }

  .tab {
    font-size: 0.875rem;
  }
}