/* ===================================
   MODERN AUTHENTICATION UI - DESIGN SYSTEM
   Premium, Responsive, Animated
   =================================== */

/* === CSS CUSTOM PROPERTIES === */
:root {
  /* Color Palette - Vibrant & Modern */
  --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --accent-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --success-gradient: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
  
  --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
  --glass-bg: rgba(255, 255, 255, 0.1);
  --glass-border: rgba(255, 255, 255, 0.2);
  
  --text-primary: #ffffff;
  --text-secondary: rgba(255, 255, 255, 0.8);
  --text-muted: rgba(255, 255, 255, 0.6);
  --text-dark: #1a1a2e;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  
  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.5rem;
  --font-size-2xl: 2rem;
  --font-size-3xl: 2.5rem;
  
  /* Border Radius */
  --radius-sm: 0.5rem;
  --radius-md: 1rem;
  --radius-lg: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
  --shadow-glow: 0 0 40px rgba(102, 126, 234, 0.4);
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* === GLOBAL RESET & BASE STYLES === */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--text-primary);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* === ANIMATED BACKGROUND === */
.auth-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-md);
  position: relative;
  background: var(--bg-gradient);
  background-size: 200% 200%;
  animation: gradientShift 15s ease infinite;
  overflow: hidden;
}

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

/* Animated particles background */
.auth-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 40% 20%, rgba(255, 255, 255, 0.08) 0%, transparent 50%);
  animation: particleFloat 20s ease-in-out infinite;
  pointer-events: none;
}

@keyframes particleFloat {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-20px) scale(1.05); }
}

/* === GLASSMORPHIC CARD === */
.auth-card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  width: 100%;
  max-width: 440px;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  position: relative;
  z-index: 1;
  animation: cardSlideIn 0.6s ease-out;
}

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

/* === TYPOGRAPHY === */
.auth-title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
  text-align: center;
  background: linear-gradient(135deg, #ffffff 0%, rgba(255, 255, 255, 0.8) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.auth-subtitle {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

/* === FORM ELEMENTS === */
.form-group {
  margin-bottom: var(--spacing-md);
  position: relative;
}

.form-input {
  width: 100%;
  padding: 1rem 1.25rem;
  font-size: var(--font-size-base);
  font-family: var(--font-family);
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-md);
  outline: none;
  transition: all var(--transition-base);
  backdrop-filter: blur(10px);
}

.form-input::placeholder {
  color: var(--text-muted);
}

.form-input:focus {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.4);
  box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
}

/* Floating label effect */
.form-group-float {
  position: relative;
  margin-bottom: var(--spacing-md);
}

.form-label {
  position: absolute;
  left: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: var(--font-size-base);
  color: var(--text-muted);
  pointer-events: none;
  transition: all var(--transition-base);
  background: transparent;
  padding: 0 0.25rem;
}

.form-input:focus + .form-label,
.form-input:not(:placeholder-shown) + .form-label {
  top: 0;
  font-size: var(--font-size-xs);
  color: var(--text-primary);
  background: rgba(102, 126, 234, 0.8);
  padding: 0.125rem 0.5rem;
  border-radius: var(--radius-sm);
}

/* === BUTTONS === */
.btn {
  width: 100%;
  padding: 1rem 2rem;
  font-size: var(--font-size-base);
  font-weight: 600;
  font-family: var(--font-family);
  color: var(--text-primary);
  background: var(--primary-gradient);
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.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 var(--transition-slow);
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg), 0 0 30px rgba(102, 126, 234, 0.5);
}

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

.btn:active {
  transform: translateY(-1px);
}

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

.btn-secondary {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  box-shadow: var(--shadow-md);
}

/* === LINKS === */
.auth-link {
  display: block;
  text-align: center;
  margin-top: var(--spacing-md);
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

.auth-link a {
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 600;
  transition: all var(--transition-fast);
  position: relative;
}

.auth-link a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--text-primary);
  transition: width var(--transition-base);
}

.auth-link a:hover::after {
  width: 100%;
}

/* === DIVIDER === */
.divider {
  display: flex;
  align-items: center;
  margin: var(--spacing-md) 0;
  color: var(--text-muted);
  font-size: var(--font-size-sm);
}

.divider::before,
.divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: rgba(255, 255, 255, 0.2);
}

.divider::before {
  margin-right: var(--spacing-sm);
}

.divider::after {
  margin-left: var(--spacing-sm);
}

/* === ALERTS === */
.alert {
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-md);
  font-size: var(--font-size-sm);
  animation: alertSlideIn 0.3s ease-out;
}

@keyframes alertSlideIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.alert-error {
  background: rgba(245, 87, 108, 0.2);
  border: 1px solid rgba(245, 87, 108, 0.4);
  color: #fff;
}

.alert-success {
  background: rgba(67, 233, 123, 0.2);
  border: 1px solid rgba(67, 233, 123, 0.4);
  color: #fff;
}

/* === LOADING SPINNER === */
.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* === DASHBOARD STYLES === */
.dashboard-container {
  min-height: 100vh;
  background: var(--bg-gradient);
  background-size: 200% 200%;
  animation: gradientShift 15s ease infinite;
}

.dashboard-header {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  padding: var(--spacing-md) var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
}

.dashboard-logo {
  font-size: var(--font-size-xl);
  font-weight: 700;
  background: linear-gradient(135deg, #ffffff 0%, rgba(255, 255, 255, 0.8) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.dashboard-user {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.user-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: var(--font-size-lg);
  box-shadow: var(--shadow-md);
}

.dashboard-content {
  padding: var(--spacing-xl);
  max-width: 1200px;
  margin: 0 auto;
}

.profile-card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
  box-shadow: var(--shadow-lg);
  animation: cardSlideIn 0.6s ease-out;
}

.profile-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.profile-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--primary-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: var(--font-size-2xl);
  box-shadow: var(--shadow-lg);
}

.profile-info h2 {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--spacing-xs);
}

.profile-info p {
  color: var(--text-secondary);
  font-size: var(--font-size-base);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.stat-card {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  transition: all var(--transition-base);
  animation: cardSlideIn 0.6s ease-out;
}

.stat-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  background: rgba(255, 255, 255, 0.15);
}

.stat-label {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stat-value {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  background: linear-gradient(135deg, #ffffff 0%, rgba(255, 255, 255, 0.8) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* === PASSWORD STRENGTH INDICATOR === */
.password-strength {
  margin-top: var(--spacing-xs);
  height: 4px;
  background: rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.password-strength-bar {
  height: 100%;
  transition: all var(--transition-base);
  border-radius: var(--radius-full);
}

.strength-weak { 
  width: 33%; 
  background: linear-gradient(90deg, #f5576c, #f093fb);
}

.strength-medium { 
  width: 66%; 
  background: linear-gradient(90deg, #f5576c, #f093fb, #4facfe);
}

.strength-strong { 
  width: 100%; 
  background: var(--success-gradient);
}

/* === RESPONSIVE DESIGN === */
@media (max-width: 768px) {
  :root {
    --font-size-3xl: 2rem;
    --font-size-2xl: 1.5rem;
    --spacing-xl: 2rem;
  }
  
  .auth-card {
    padding: var(--spacing-lg);
  }
  
  .dashboard-header {
    padding: var(--spacing-sm) var(--spacing-md);
  }
  
  .dashboard-content {
    padding: var(--spacing-md);
  }
  
  .profile-header {
    flex-direction: column;
    text-align: center;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .auth-container {
    padding: var(--spacing-sm);
  }
  
  .auth-card {
    padding: var(--spacing-md);
  }
  
  .btn {
    padding: 0.875rem 1.5rem;
  }
}

/* === UTILITY CLASSES === */
.text-center { text-align: center; }
.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.hidden { display: none; }
.modal-overlay.hidden { display: none !important; }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: var(--spacing-sm); }