/* ============================================
   MastersCS - Global Styles
   ============================================ */

/* Variables */
:root {
  --primary: #25D366;
  --primary-dark: #128C7E;
  --secondary: #075E54;
  --accent: #00A884;
  --background: #F0F2F5;
  --surface: #FFFFFF;
  --text-primary: #111B21;
  --text-secondary: #667781;
  --border: #E9EDEF;
  --success: #25D366;
  --warning: #FFA726;
  --danger: #EF5350;
  --info: #29B6F6;
  
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
}

/* Reset */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* Typography */
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--background);
  color: var(--text-primary);
  line-height: 1.6;
  font-size: 14px;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
}

a {
  color: var(--primary);
  text-decoration: none;
}

/* Utility Classes */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 20px;
}

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 4px; }
.gap-2 { gap: 8px; }
.gap-3 { gap: 12px; }
.gap-4 { gap: 16px; }

.text-center { text-align: center; }
.text-right { text-align: right; }

.mt-1 { margin-top: 4px; }
.mt-2 { margin-top: 8px; }
.mt-3 { margin-top: 12px; }
.mt-4 { margin-top: 16px; }
.mb-1 { margin-bottom: 4px; }
.mb-2 { margin-bottom: 8px; }
.mb-3 { margin-bottom: 12px; }
.mb-4 { margin-bottom: 16px; }

.p-2 { padding: 8px; }
.p-3 { padding: 12px; }
.p-4 { padding: 16px; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
}

.btn-primary:hover {
  box-shadow: 0 4px 12px rgba(37, 211, 102, 0.3);
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--background);
  color: var(--text-secondary);
}

.btn-secondary:hover {
  background: var(--border);
}

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

.btn-danger:hover {
  background: #D32F2F;
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--background);
}

.btn-sm {
  padding: 6px 12px;
  font-size: 12px;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 16px;
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: 50%;
}

/* Cards */
.card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.card-header {
  padding: 20px;
  border-bottom: 1px solid var(--border);
}

.card-body {
  padding: 20px;
}

.card-footer {
  padding: 15px 20px;
  border-top: 1px solid var(--border);
  background: var(--background);
}

/* Forms */
.form-group {
  margin-bottom: 20px;
}

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.form-input {
  width: 100%;
  padding: 12px 15px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-family: inherit;
  transition: all 0.2s ease;
}

.form-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 211, 102, 0.1);
}

.form-input::placeholder {
  color: #ADB5BD;
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%23667781' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10l-5 5z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 15px center;
  padding-right: 40px;
}

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
}

.table th,
.table td {
  padding: 12px 15px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.table th {
  background: var(--background);
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.table tr:hover {
  background: var(--background);
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 11px;
  font-weight: 600;
}

.badge-success { background: #E8F5E9; color: #4CAF50; }
.badge-warning { background: #FFF3E0; color: #FF9800; }
.badge-danger { background: #FFEBEE; color: #EF5350; }
.badge-info { background: #E3F2FD; color: #2196F3; }
.badge-neutral { background: #F5F5F5; color: #757575; }

/* Alerts */
.alert {
  padding: 15px 20px;
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.alert-success { background: #E8F5E9; color: #2E7D32; }
.alert-warning { background: #FFF3E0; color: #F57C00; }
.alert-danger { background: #FFEBEE; color: #C62828; }
.alert-info { background: #E3F2FD; color: #1565C0; }

/* Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: var(--surface);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  transform: scale(0.9);
  transition: transform 0.3s ease;
}

.modal-overlay.active .modal {
  transform: scale(1);
}

.modal-header {
  padding: 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-size: 18px;
  font-weight: 600;
}

.modal-close {
  width: 32px;
  height: 32px;
  border: none;
  background: var(--background);
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
}

.modal-close:hover {
  background: var(--border);
}

.modal-body {
  padding: 20px;
}

.modal-footer {
  padding: 15px 20px;
  border-top: 1px solid var(--border);
  display: flex;
  gap: 10px;
  justify-content: flex-end;
}

/* Toast */
.toast-container {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.toast {
  background: var(--surface);
  border-radius: var(--radius-md);
  padding: 15px 20px;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: 12px;
  animation: slideIn 0.3s ease;
}

.toast-success { border-left: 4px solid var(--success); }
.toast-error { border-left: 4px solid var(--danger); }
.toast-warning { border-left: 4px solid var(--warning); }
.toast-info { border-left: 4px solid var(--info); }

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

/* Loading Spinner */
.spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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

/* Responsive */
@media (max-width: 768px) {
  .hide-mobile { display: none !important; }
}

@media (min-width: 769px) {
  .hide-desktop { display: none !important; }
}