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

:root {
  --bg: #f8f9fa;
  --surface: #ffffff;
  --border: #e5e7eb;
  --text: #111827;
  --text-muted: #6b7280;
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --primary-light: #eff6ff;
  --danger: #ef4444;
  --success: #10b981;
  --warning: #f59e0b;
  --sidebar-bg: #1f2937;
  --sidebar-text: #d1d5db;
  --sidebar-active: #fff;
}

* { box-sizing: border-box; }
html, body { height: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* LOGIN */
#login-screen {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.login-box {
  background: var(--surface);
  border-radius: 16px;
  padding: 48px;
  width: 100%;
  max-width: 380px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.15);
}

.login-logo {
  font-size: 28px;
  font-weight: 800;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
  letter-spacing: -0.5px;
}

.login-sub {
  color: var(--text-muted);
  margin-bottom: 32px;
  font-size: 14px;
}

.error-msg {
  color: var(--danger);
  font-size: 13px;
  margin-top: 12px;
  padding: 8px 12px;
  background: #fee2e2;
  border-radius: 6px;
}

/* LAYOUT */
#app {
  display: flex;
  height: 100vh;
  overflow: hidden;
  background: var(--bg);
}

.sidebar {
  width: 240px;
  background: var(--sidebar-bg);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  border-right: 1px solid rgba(255,255,255,0.05);
  box-shadow: 2px 0 8px rgba(0,0,0,0.1);
}

.sidebar-logo {
  padding: 28px 20px 24px;
  font-size: 20px;
  font-weight: 800;
  color: var(--sidebar-active);
  letter-spacing: -0.5px;
}

nav {
  flex: 1;
  padding: 12px 8px;
  overflow-y: auto;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  border-radius: 10px;
  color: var(--sidebar-text);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 4px;
  transition: all 0.2s ease;
}

.nav-item:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--sidebar-active);
}

.nav-item.active {
  background: rgba(59, 130, 246, 0.15);
  color: var(--primary);
  font-weight: 600;
}

.nav-icon {
  font-size: 10px;
  opacity: 0.6;
}

.sidebar-footer {
  padding: 16px 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.sidebar-footer span {
  display: block;
  color: var(--sidebar-text);
  font-size: 12px;
  margin-bottom: 10px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.main-content {
  flex: 1;
  overflow-y: auto;
  padding: 40px;
  background: var(--bg);
}

/* PAGES */
.page {
  display: none;
  animation: fadeIn 0.3s ease-in;
}

.page.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.page-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
}

h1 {
  font-size: 28px;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.5px;
}

h2 {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 20px;
}

/* STATS */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 32px;
}

.stat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
  transition: all 0.2s ease;
}

.stat-card:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.1);
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 10px;
}

.stat-value {
  font-size: 32px;
  font-weight: 800;
  color: var(--text);
}

/* CARD */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

/* TABLE */
.table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.table th {
  text-align: left;
  padding: 12px 14px;
  border-bottom: 2px solid var(--border);
  font-weight: 600;
  color: var(--text-muted);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: #f9fafb;
}

.table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
}

.table tr:last-child td {
  border-bottom: none;
}

.table tr:hover td {
  background: #fafbfc;
}

/* LISTS */
.list-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all 0.2s ease;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.list-card:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.1);
}

.list-info h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.list-info p {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 4px;
}

.list-actions {
  display: flex;
  gap: 8px;
}

/* CAMPAIGN CARD */
.campaign-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 14px;
  transition: all 0.2s ease;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.campaign-card:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.1);
}

.campaign-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.campaign-name {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.campaign-meta {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 4px;
}

.campaign-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--border);
}

.campaign-actions {
  display: flex;
  gap: 8px;
}

/* BADGES */
.badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
}

.badge-draft {
  background: #f3f4f6;
  color: #6b7280;
}

.badge-sending {
  background: #dbeafe;
  color: #1e40af;
}

.badge-sent {
  background: #dcfce7;
  color: #166534;
}

.badge-failed {
  background: #fee2e2;
  color: #991b1b;
}

.badge-paused {
  background: #fef3c7;
  color: #92400e;
}

/* FORMS */
.field {
  margin-bottom: 20px;
}

.field label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text);
}

.field input,
.field select,
.field textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  color: var(--text);
  background: var(--surface);
  transition: all 0.15s ease;
  outline: none;
}

.field input:hover,
.field select:hover,
.field textarea:hover {
  border-color: #d1d5db;
}

.field input:focus,
.field select:focus,
.field textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.field textarea {
  resize: vertical;
  font-family: 'Monaco', 'Courier New', monospace;
  font-size: 13px;
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 24px;
}

.field-full {
  grid-column: 1 / -1;
}

.hint {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

code {
  background: #f3f4f6;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 12px;
  font-family: 'Monaco', 'Courier New', monospace;
}

/* BUTTONS */
.btn-primary {
  background: var(--primary);
  color: #fff;
  border: none;
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 2px 4px rgba(59, 130, 246, 0.2);
}

.btn-primary:hover {
  background: var(--primary-hover);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
  transform: translateY(-1px);
}

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

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
  padding: 9px 18px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-ghost:hover {
  border-color: var(--text-muted);
  color: var(--text);
  background: #f9fafb;
}

.btn-danger {
  background: transparent;
  color: var(--danger);
  border: 1px solid #fecaca;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-danger:hover {
  background: #fef2f2;
  border-color: var(--danger);
}

.btn-sm {
  padding: 7px 14px;
  font-size: 13px;
}

.btn-send {
  background: var(--success);
  color: #fff;
  border: none;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-send:hover {
  background: #059669;
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.btn-warning {
  background: var(--warning);
  color: #fff;
  border: none;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-warning:hover {
  background: #d97706;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

/* MODAL */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  backdrop-filter: blur(2px);
}

.modal-box {
  background: var(--surface);
  border-radius: 16px;
  padding: 32px;
  width: 480px;
  max-height: 85vh;
  overflow-y: auto;
  box-shadow: 0 25px 50px rgba(0, 0, 0, 0.15);
  animation: slideUp 0.3s ease;
}

.modal-wide {
  width: 720px;
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

/* STATS MODAL */
.stats-row {
  display: flex;
  justify-content: space-between;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}

.stats-row:last-child {
  border-bottom: none;
}

.stats-row span:first-child {
  color: var(--text-muted);
  font-weight: 500;
}

.stats-row span:last-child {
  font-weight: 700;
  color: var(--text);
}

/* EMPTY STATE */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
}

.empty-state p {
  margin-top: 8px;
  font-size: 14px;
}

/* SANDBOX NOTICE */
.sandbox-notice {
  background: #fffbeb;
  border: 1px solid #fde68a;
  border-radius: 8px;
  padding: 14px 16px;
  margin-bottom: 24px;
  font-size: 13px;
  color: #92400e;
}

/* RESPONSIVE */
@media (max-width: 1024px) {
  .main-content {
    padding: 24px;
  }

  .form-grid {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .modal-box {
    width: 90vw;
    max-width: 480px;
  }
}

@media (max-width: 768px) {
  .sidebar {
    width: 200px;
  }

  .main-content {
    padding: 16px;
  }

  h1 {
    font-size: 24px;
  }

  .stats-grid {
    grid-template-columns: 1fr;
  }

  .page-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
  }

  .page-header button {
    align-self: flex-end;
  }
}