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

body {
  font-family:
    "Inter",
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    Oxygen,
    Ubuntu,
    sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #333;
  position: relative;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image:
    radial-gradient(
      circle at 20% 50%,
      rgba(120, 119, 198, 0.3) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 80% 80%,
      rgba(255, 119, 198, 0.3) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 40% 20%,
      rgba(255, 255, 255, 0.1) 0%,
      transparent 50%
    );
  z-index: -1;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
  animation: fadeInUp 0.8s ease-out;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Header Styles */
.header {
  text-align: center;
  margin-bottom: 3rem;
}

.logo-container {
  margin-bottom: 1.5rem;
  animation: scaleIn 0.5s ease-out;
}

@keyframes scaleIn {
  from {
    transform: scale(0.8);
    opacity: 0;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}

.logo {
  width: 150px;
  height: auto;
  filter: drop-shadow(0 10px 30px rgba(0, 0, 0, 0.2));
  transition: transform 0.3s ease;
}

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

.title {
  font-size: 3rem;
  font-weight: 700;
  color: white;
  margin-bottom: 0.5rem;
  text-shadow: 2px 4px 8px rgba(0, 0, 0, 0.2);
  letter-spacing: -0.5px;
}

.subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.9);
  font-weight: 300;
  letter-spacing: 0.5px;
}

/* Main Content */
.main-content {
  margin-bottom: 3rem;
}

.auth-options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
  gap: 2rem;
  max-width: 800px;
  margin: 0 auto;
}

.auth-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  padding: 3rem 2rem;
  text-align: center;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.auth-card::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(
    45deg,
    transparent,
    rgba(255, 255, 255, 0.1),
    transparent
  );
  transform: rotate(45deg);
  transition: all 0.5s ease;
}

.auth-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.2);
}

.auth-card:hover::before {
  animation: shine 0.5s ease;
}

@keyframes shine {
  0% {
    transform: rotate(45deg) translateY(-200%);
  }
  100% {
    transform: rotate(45deg) translateY(200%);
  }
}

.card-icon {
  margin-bottom: 1.5rem;
  display: inline-flex;
  padding: 1rem;
  background: linear-gradient(
    135deg,
    rgba(74, 144, 226, 0.1) 0%,
    rgba(74, 144, 226, 0.05) 100%
  );
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.auth-card:nth-child(2) .card-icon {
  background: linear-gradient(
    135deg,
    rgba(40, 167, 69, 0.1) 0%,
    rgba(40, 167, 69, 0.05) 100%
  );
}

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(74, 144, 226, 0.4);
  }
  70% {
    box-shadow: 0 0 0 10px rgba(74, 144, 226, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(74, 144, 226, 0);
  }
}

.card-title {
  font-size: 1.75rem;
  font-weight: 600;
  color: #2c3e50;
  margin-bottom: 1rem;
}

.card-description {
  font-size: 1rem;
  color: #6c757d;
  margin-bottom: 2rem;
  line-height: 1.6;
}

/* Button Styles */
.btn {
  padding: 1rem 2.5rem;
  font-size: 1.1rem;
  font-weight: 500;
  border: none;
  border-radius: 50px;
  cursor: pointer;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.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;
}

.btn:hover::before {
  left: 100%;
}

.btn-primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.btn-success {
  background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
  color: white;
}

.btn-success:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(40, 167, 69, 0.4);
}

/* Footer Styles */
.footer {
  text-align: center;
  color: white;
  opacity: 0.9;
}

.security-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  padding: 0.5rem 1rem;
  border-radius: 25px;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

.security-badge svg {
  stroke: white;
}

.copyright {
  font-size: 0.9rem;
  opacity: 0.8;
}

/* ==========================================
   Responsive Design — Tablet (≤ 768px)
   ========================================== */
@media (max-width: 768px) {
  .title {
    font-size: 2rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .auth-options {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

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

  .card-title {
    font-size: 1.5rem;
  }

  .btn {
    padding: 0.875rem 2rem;
    font-size: 1rem;
    min-height: 48px;
  }

  .container {
    padding: 1.5rem;
  }

  .header {
    margin-bottom: 2rem;
  }

  .logo {
    width: 120px;
  }
}

/* ==========================================
   Responsive Design — Small phones (≤ 480px)
   ========================================== */
@media (max-width: 480px) {
  .container {
    padding: 1rem;
  }

  .title {
    font-size: 1.65rem;
    letter-spacing: -0.3px;
  }

  .subtitle {
    font-size: 0.9rem;
  }

  .header {
    margin-bottom: 1.5rem;
  }

  .logo {
    width: 100px;
  }

  .auth-card {
    padding: 1.5rem 1.25rem;
    border-radius: 16px;
  }

  .card-icon {
    margin-bottom: 1rem;
  }

  .card-title {
    font-size: 1.3rem;
    margin-bottom: 0.75rem;
  }

  .card-description {
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
  }

  .btn {
    padding: 0.75rem 1.5rem;
    font-size: 0.95rem;
    min-height: 44px;
  }

  .security-badge {
    font-size: 0.8rem;
    padding: 0.4rem 0.75rem;
  }

  .copyright {
    font-size: 0.8rem;
  }

  .footer {
    margin-top: 1.5rem;
  }

  .main-content {
    margin-bottom: 2rem;
  }
}

/* Loading Animation */
@keyframes gradient {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

/* Accessibility */
.btn:focus,
.btn:active {
  outline: 3px solid rgba(255, 255, 255, 0.5);
  outline-offset: 2px;
}

/* Additional hover effects */
.logo-container {
  position: relative;
}

.logo-container::after {
  content: "";
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60%;
  height: 2px;
  background: linear-gradient(90deg, transparent, white, transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.logo-container:hover::after {
  opacity: 0.6;
}