/* Material Design CSS for Certificate Management System */

/* Import Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&display=swap');
@import url('https://fonts.googleapis.com/icon?family=Material+Icons');

/* CSS Variables for Material Design */
:root {
  /* Primary Colors */
  --primary-50: #e8eaf6;
  --primary-100: #c5cae9;
  --primary-200: #9fa8da;
  --primary-300: #7986cb;
  --primary-400: #5c6bc0;
  --primary-500: #3f51b5;
  --primary-600: #3949ab;
  --primary-700: #303f9f;
  --primary-800: #283593;
  --primary-900: #1a237e;

  /* Secondary Colors */
  --secondary-200: #f8bbd9;
  --secondary-400: #f06292;
  --secondary-500: #e91e63;

  /* Surface Colors */
  --surface: #ffffff;
  --background: #fafafa;
  --surface-variant: #f5f5f5;
  
  /* Text Colors */
  --on-surface: #1c1b1f;
  --on-surface-variant: #49454f;
  --on-primary: #ffffff;
  
  /* State Colors */
  --success: #4caf50;
  --warning: #ff9800;
  --error: #f44336;
  --info: #2196f3;

  /* Shadows */
  --elevation-1: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
  --elevation-2: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
  --elevation-3: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);
  --elevation-4: 0 14px 28px rgba(0,0,0,0.25), 0 10px 10px rgba(0,0,0,0.22);
  --elevation-5: 0 19px 38px rgba(0,0,0,0.30), 0 15px 12px rgba(0,0,0,0.22);

  /* Border Radius */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-2xl: 48px;
}

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

body {
  font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: var(--background);
  color: var(--on-surface);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 500;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
}

h1 { font-size: 2.125rem; font-weight: 400; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }
h5 { font-size: 1rem; }
h6 { font-size: 0.875rem; }

p { margin-bottom: var(--spacing-md); }

/* Navigation Bar */
.navbar {
  background: var(--surface);
  box-shadow: var(--elevation-2);
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(0,0,0,0.12);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--primary-700);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

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

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: var(--on-surface-variant);
  font-weight: 500;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
}

.nav-link:hover {
  background-color: var(--primary-50);
  color: var(--primary-700);
}

.nav-link.active {
  background-color: var(--primary-100);
  color: var(--primary-700);
}

.nav-user {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-left: var(--spacing-lg);
  padding-left: var(--spacing-lg);
  border-left: 1px solid rgba(0,0,0,0.12);
}

.nav-user span {
  font-size: 0.875rem;
  color: var(--on-surface-variant);
}

.logout {
  color: var(--error) !important;
}

.logout:hover {
  background-color: rgba(244, 67, 54, 0.08) !important;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-lg);
}

/* Page Header */
.page-header {
  margin-bottom: var(--spacing-2xl);
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: var(--spacing-lg);
}

.page-header h1 {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  color: var(--on-surface);
  margin-bottom: var(--spacing-xs);
}

.page-header p {
  color: var(--on-surface-variant);
  margin-bottom: 0;
}

.page-actions {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
}

/* Material Design Cards */
.card, .dashboard-card, .stat-card, .client-card, .certificate-card {
  background: var(--surface);
  border-radius: var(--radius-md);
  box-shadow: var(--elevation-1);
  transition: box-shadow 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
}

.card:hover, .dashboard-card:hover, .client-card:hover, .certificate-card:hover {
  box-shadow: var(--elevation-2);
}

.card-header, .certificate-header {
  padding: var(--spacing-lg);
  border-bottom: 1px solid rgba(0,0,0,0.12);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.card-content, .certificate-content {
  padding: var(--spacing-lg);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: 10px 24px;
  border: none;
  border-radius: var(--radius-lg);
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.btn:before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255,255,255,0.3);
  transition: width 0.6s, height 0.6s, top 0.6s, left 0.6s;
  transform: translate(-50%, -50%);
}

.btn:active:before {
  width: 300px;
  height: 300px;
}

.btn-primary {
  background: var(--primary-500);
  color: var(--on-primary);
}

.btn-primary:hover {
  background: var(--primary-600);
  box-shadow: var(--elevation-2);
}

.btn-secondary {
  background: var(--secondary-500);
  color: var(--on-primary);
}

.btn-secondary:hover {
  background: var(--secondary-400);
  box-shadow: var(--elevation-2);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--primary-500);
  color: var(--primary-500);
}

.btn-outline:hover {
  background: var(--primary-50);
}

.btn-success {
  background: var(--success);
  color: white;
}

.btn-warning {
  background: var(--warning);
  color: white;
}

.btn-error {
  background: var(--error);
  color: white;
}

.btn-sm {
  padding: 6px 16px;
  font-size: 0.75rem;
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1rem;
}

/* Floating Action Button */
.fab {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--primary-500);
  color: var(--on-primary);
  border: none;
  box-shadow: var(--elevation-3);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  position: fixed;
  bottom: var(--spacing-lg);
  right: var(--spacing-lg);
  z-index: 1000;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.fab:hover {
  box-shadow: var(--elevation-4);
  transform: scale(1.1);
}

/* Forms */
.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-group label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
  color: var(--on-surface);
}

.form-control, input, textarea, select {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid rgba(0,0,0,0.12);
  border-radius: var(--radius-xs);
  font-family: inherit;
  font-size: 1rem;
  background: var(--surface);
  color: var(--on-surface);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.form-control:focus, input:focus, textarea:focus, select:focus {
  outline: none;
  border-color: var(--primary-500);
  box-shadow: 0 0 0 3px rgba(63, 81, 181, 0.12);
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-2xl);
}

.stat-card {
  padding: var(--spacing-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.stat-icon {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--on-primary);
}

.stat-icon.clients { background: linear-gradient(135deg, var(--primary-500), var(--primary-700)); }
.stat-icon.certificates { background: linear-gradient(135deg, var(--success), #388e3c); }
.stat-icon.activities { background: linear-gradient(135deg, var(--info), #1976d2); }

.stat-content h3 {
  font-size: 2.5rem;
  font-weight: 300;
  margin-bottom: var(--spacing-xs);
  color: var(--on-surface);
}

.stat-content p {
  color: var(--on-surface-variant);
  margin-bottom: 0;
  font-size: 0.875rem;
}

/* Dashboard Grid */
.dashboard-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: var(--spacing-lg);
}

/* Quick Actions */
.quick-actions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
}

.action-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-lg);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: var(--on-surface);
  background: var(--surface-variant);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: center;
}

.action-btn:hover {
  background: var(--primary-50);
  color: var(--primary-700);
  transform: translateY(-2px);
  box-shadow: var(--elevation-2);
}

.action-btn i {
  font-size: 2rem;
  margin-bottom: var(--spacing-xs);
}

/* Activity List */
.activity-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.activity-item {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  border-radius: var(--radius-sm);
  transition: background-color 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.activity-item:hover {
  background: var(--surface-variant);
}

.activity-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary-100);
  color: var(--primary-700);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.activity-content {
  flex: 1;
}

.activity-text {
  margin-bottom: var(--spacing-xs);
  font-size: 0.875rem;
}

.activity-time {
  color: var(--on-surface-variant);
  font-size: 0.75rem;
}

/* Alerts */
.alert {
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--radius-sm);
  margin-bottom: var(--spacing-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.alert-success {
  background: rgba(76, 175, 80, 0.1);
  color: #2e7d32;
  border-left: 4px solid var(--success);
}

.alert-error {
  background: rgba(244, 67, 54, 0.1);
  color: #c62828;
  border-left: 4px solid var(--error);
}

.alert-warning {
  background: rgba(255, 152, 0, 0.1);
  color: #ef6c00;
  border-left: 4px solid var(--warning);
}

.alert-info {
  background: rgba(33, 150, 243, 0.1);
  color: #1565c0;
  border-left: 4px solid var(--info);
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: var(--spacing-2xl);
  color: var(--on-surface-variant);
}

.empty-icon {
  font-size: 4rem;
  color: var(--primary-200);
  margin-bottom: var(--spacing-lg);
}

.empty-state h3 {
  color: var(--on-surface);
  margin-bottom: var(--spacing-md);
}

/* Loading */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-lg);
  color: var(--on-surface-variant);
}

/* Login Page */
.login-body {
  background: linear-gradient(135deg, var(--primary-500), var(--primary-700));
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.login-container {
  width: 100%;
  max-width: 400px;
  padding: var(--spacing-lg);
}

.login-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--elevation-5);
  overflow: hidden;
}

.login-header {
  padding: var(--spacing-2xl) var(--spacing-lg) var(--spacing-lg);
  text-align: center;
  background: var(--surface);
}

.login-header i {
  font-size: 3rem;
  color: var(--primary-500);
  margin-bottom: var(--spacing-md);
}

.login-header h1 {
  color: var(--on-surface);
  margin-bottom: var(--spacing-sm);
}

.login-header p {
  color: var(--on-surface-variant);
  margin-bottom: 0;
}

.login-form {
  padding: var(--spacing-lg);
}

.login-btn {
  width: 100%;
  justify-content: center;
  margin-top: var(--spacing-md);
}

.login-footer {
  padding: var(--spacing-lg);
  text-align: center;
  background: var(--surface-variant);
  color: var(--on-surface-variant);
  font-size: 0.75rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav-container {
    padding: 0 var(--spacing-md);
    flex-wrap: wrap;
    height: auto;
    min-height: 64px;
  }
  
  .nav-menu {
    order: 3;
    width: 100%;
    justify-content: space-around;
    padding: var(--spacing-md) 0;
    border-top: 1px solid rgba(0,0,0,0.12);
  }
  
  .nav-user {
    margin-left: 0;
    padding-left: 0;
    border-left: none;
  }
  
  .container {
    padding: var(--spacing-lg) var(--spacing-md);
  }
  
  .page-header {
    flex-direction: column;
    align-items: stretch;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .dashboard-grid {
    grid-template-columns: 1fr;
  }
  
  .quick-actions {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .quick-actions {
    grid-template-columns: 1fr;
  }
  
  .fab {
    bottom: var(--spacing-md);
    right: var(--spacing-md);
  }
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
  from { transform: translateX(-100%); }
  to { transform: translateX(0); }
}

.fade-in {
  animation: fadeIn 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-in {
  animation: slideIn 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Utility Classes */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }

.p-0 { padding: 0; }
.p-1 { padding: var(--spacing-xs); }
.p-2 { padding: var(--spacing-sm); }
.p-3 { padding: var(--spacing-md); }
.p-4 { padding: var(--spacing-lg); }