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

:root {
  --primary: #1976d2;
  --primary-dark: #1565c0;
  --danger: #f44336;
  --success: #4caf50;
  --bg-dark: #0d1b2a;
  --panel-bg: rgba(20, 30, 40, 0.92);
  --text-light: #e0e0e0;
  --text-muted: #aaa;
  --border-color: #333;
}

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: linear-gradient(135deg, var(--bg-dark), #1a2a3a, #0d1b2a);
  color: var(--text-light);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
  overflow: hidden;
}

.loader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-dark);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  opacity: 1;
  transition: opacity 0.6s ease;
}

.loader.hidden {
  opacity: 0;
  pointer-events: none;
}

.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid rgba(255, 255, 255, 0.3);
  border-top: 4px solid var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: 16px;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

#main.hidden {
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
}

#main {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.8s ease, transform 0.6s ease;
  width: 100%;
  max-width: 400px;
}

.login-container {
  background: var(--panel-bg);
  backdrop-filter: blur(8px);
  border-radius: 16px;
  padding: 32px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.5);
  text-align: center;
  animation: fadeInUp 0.8s ease forwards;
  opacity: 0;
  transform: translateY(30px);
}

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

.logo .cloud-icon {
  font-size: 2.2rem;
  display: block;
  margin-bottom: 12px;
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.logo h1 {
  font-size: 1.6rem;
  font-weight: 600;
  color: #bbdefb;
}

.login-form {
  text-align: left;
}

.input-group {
  position: relative;
  margin-bottom: 24px;
}

.input-group label {
  display: block;
  font-size: 0.85rem;
  margin-bottom: 6px;
  color: var(--text-muted);
  transition: color 0.3s;
}

.input-group input {
  width: 100%;
  padding: 12px 14px;
  background: rgba(10, 15, 20, 0.7);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: white;
  font-size: 1rem;
  outline: none;
  transition: border-color 0.3s, background 0.3s;
}

.input-group input:focus {
  border-color: var(--primary);
  background: rgba(25, 35, 45, 0.9);
}

.input-border {
  position: absolute;
  bottom: 0;
  left: 0;
  height: 2px;
  width: 0;
  background: var(--primary);
  transition: width 0.4s ease;
}

.input-group input:focus ~ .input-border {
  width: 100%;
}

.btn-submit {
  width: 100%;
  padding: 13px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 8px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.btn-submit:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(25, 118, 210, 0.3);
}

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

.btn-submit::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 5px;
  height: 5px;
  background: rgba(255, 255, 255, 0.5);
  opacity: 0;
  border-radius: 100%;
  transform: scale(1, 1) translate(-50%);
  transform-origin: 50% 50%;
}

.btn-submit:focus:not(:active)::after {
  animation: ripple 0.6s ease-out;
}

@keyframes ripple {
  0% {
    transform: scale(0, 0);
    opacity: 0.5;
  }
  100% {
    transform: scale(50, 50);
    opacity: 0;
  }
}

.error-message {
  color: var(--danger);
  font-size: 0.9rem;
  margin-top: 16px;
  text-align: center;
  height: 20px;
  opacity: 0;
  transform: translateY(-10px);
  transition: opacity 0.4s, transform 0.4s;
}

.error-message.show {
  opacity: 1;
  transform: translateY(0);
}

.login-footer {
  margin-top: 30px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

@media (max-width: 480px) {
  .login-container {
    padding: 24px 20px;
  }

  .logo h1 {
    font-size: 1.4rem;
  }

  .input-group input {
    padding: 11px;
    font-size: 0.95rem;
  }

  .btn-submit {
    padding: 12px;
  }
}

@media (max-width: 360px) {
  body {
    padding: 10px;
  }

  .login-container {
    padding: 20px 16px;
  }
}