:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-card: #1e293b;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #38bdf8;
  --accent-hover: #0284c7;
  --accent-light: rgba(56, 189, 248, 0.15);
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --border: #334155;
  --radius: 8px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root[data-theme="light"] {
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --accent: #0284c7;
    --accent-hover: #0369a1;
    --accent-light: rgba(2, 132, 199, 0.1);
    --border: #e2e8f0;
  }
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  font-size: 14px;
  height: 100vh;
  overflow: hidden;
}

/* Layout */
.app-container {
  display: flex;
  height: 100vh;
  width: 100vw;
  overflow: hidden;
}

/* Sidebar */
.sidebar {
  width: 260px;
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}

.brand-header {
  padding: 18px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  border-bottom: 1px solid var(--border);
}

.brand-logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--accent);
  display: flex;
  align-items: center;
  gap: 8px;
}

.badge-tag {
  font-size: 10px;
  background: var(--accent-light);
  color: var(--accent);
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
  text-transform: uppercase;
}

.sidebar-content {
  padding: 16px 12px;
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.btn-compose {
  width: 100%;
  background-color: var(--accent);
  color: #ffffff;
  border: none;
  padding: 10px 16px;
  border-radius: var(--radius);
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: background 0.15s ease;
}
.btn-compose:hover { background-color: var(--accent-hover); }

.nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-radius: var(--radius);
  color: var(--text-secondary);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.15s ease;
}

.nav-item:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.nav-item.active {
  background-color: var(--accent-light);
  color: var(--accent);
  font-weight: 600;
}

.nav-badge {
  background: var(--accent);
  color: #fff;
  font-size: 11px;
  padding: 1px 7px;
  border-radius: 10px;
  font-weight: 600;
}

.sidebar-footer {
  padding: 16px;
  border-top: 1px solid var(--border);
  font-size: 12px;
  color: var(--text-muted);
}

.storage-meter {
  margin-top: 6px;
  background: var(--bg-tertiary);
  border-radius: 4px;
  height: 6px;
  overflow: hidden;
}

.storage-bar {
  background: var(--accent);
  height: 100%;
  width: 0%;
  transition: width 0.3s ease;
}

/* Mail List Column */
.mail-list-col {
  width: 380px;
  background: var(--bg-primary);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}

.search-box {
  padding: 14px;
  border-bottom: 1px solid var(--border);
}

.search-input {
  width: 100%;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 8px 12px;
  color: var(--text-primary);
  font-size: 13px;
  outline: none;
}
.search-input:focus { border-color: var(--accent); }

.mail-list-items {
  flex: 1;
  overflow-y: auto;
}

.mail-item {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: background 0.1s ease;
}

.mail-item:hover { background-color: var(--bg-secondary); }
.mail-item.active {
  background-color: var(--accent-light);
  border-left: 3px solid var(--accent);
}
.mail-item.unread .mail-sender { font-weight: 700; color: var(--text-primary); }
.mail-item.unread .mail-subject { font-weight: 600; color: var(--text-primary); }

.mail-header-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}

.mail-sender {
  font-size: 13px;
  color: var(--text-secondary);
  max-width: 220px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.mail-date {
  font-size: 11px;
  color: var(--text-muted);
}

.mail-subject {
  font-size: 13px;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  margin-bottom: 4px;
}

.mail-snippet {
  font-size: 12px;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: flex;
  align-items: center;
  gap: 6px;
}

.attachment-tag {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  font-size: 10px;
  color: var(--accent);
  background: var(--accent-light);
  padding: 1px 5px;
  border-radius: 4px;
}

/* Mail Detail Pane */
.mail-detail-pane {
  flex: 1;
  background: var(--bg-secondary);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.detail-toolbar {
  padding: 12px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.toolbar-group {
  display: flex;
  gap: 8px;
}

.btn-tool {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  padding: 6px 12px;
  border-radius: var(--radius);
  font-size: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
}
.btn-tool:hover { background: var(--border); }
.btn-tool.danger { color: var(--danger); }
.btn-tool.danger:hover { background: rgba(239, 68, 68, 0.15); border-color: var(--danger); }

.detail-content {
  flex: 1;
  overflow-y: auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.detail-subject {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
}

.detail-meta-card {
  background: var(--bg-primary);
  padding: 14px 18px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.meta-row {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
}

.meta-label {
  color: var(--text-muted);
  width: 50px;
}

.meta-val {
  color: var(--text-primary);
  font-weight: 500;
}

.sec-pill {
  font-size: 10px;
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
}
.sec-pass { background: rgba(16, 185, 129, 0.15); color: var(--success); }
.sec-fail { background: rgba(239, 68, 68, 0.15); color: var(--danger); }

/* Attachments Block */
.attachments-section {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-primary);
  padding: 14px 18px;
}

.attachments-title {
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.attachment-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 10px;
}

.attachment-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 12px;
}

.attachment-info {
  display: flex;
  align-items: center;
  gap: 8px;
  overflow: hidden;
}

.att-name {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 130px;
  font-weight: 500;
}

.att-size {
  color: var(--text-muted);
  font-size: 11px;
}

.btn-download {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  padding: 4px 8px;
  border-radius: 4px;
  background: var(--accent-light);
}
.btn-download:hover { background: var(--accent); color: #fff; }

.mail-body-frame {
  width: 100%;
  min-height: 350px;
  background: #ffffff;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

/* Modals */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  backdrop-filter: blur(2px);
}

.modal {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 680px;
  max-width: 95vw;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
}

.modal-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal-title {
  font-size: 16px;
  font-weight: 700;
}

.btn-close {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 20px;
  cursor: pointer;
}
.btn-close:hover { color: var(--text-primary); }

.modal-body {
  padding: 20px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
}

.form-input, .form-textarea, .form-select {
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 8px 12px;
  color: var(--text-primary);
  font-size: 13px;
  outline: none;
}
.form-input:focus, .form-textarea:focus, .form-select:focus {
  border-color: var(--accent);
}

.form-textarea { min-height: 160px; resize: vertical; font-family: inherit; }

/* File Drop Zone */
.dropzone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 20px;
  text-align: center;
  color: var(--text-muted);
  cursor: pointer;
  transition: border 0.15s ease;
}
.dropzone:hover, .dropzone.dragover {
  border-color: var(--accent);
  background: var(--accent-light);
}

.file-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 8px;
}

.file-pill {
  background: var(--bg-tertiary);
  padding: 4px 10px;
  border-radius: 12px;
  font-size: 11px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.file-pill .remove-file {
  cursor: pointer;
  color: var(--danger);
  font-weight: bold;
}

.modal-footer {
  padding: 14px 20px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.btn {
  padding: 8px 16px;
  border-radius: var(--radius);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-secondary { background: var(--bg-tertiary); color: var(--text-primary); border-color: var(--border); }
.btn-secondary:hover { background: var(--border); }

/* Admin Dashboard Specific */
.admin-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px;
  width: 100%;
  overflow-y: auto;
  height: 100vh;
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.stat-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.stat-title {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  font-weight: 600;
}

.stat-value {
  font-size: 24px;
  font-weight: 700;
  color: var(--accent);
}

.stat-sub {
  font-size: 11px;
  color: var(--text-secondary);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-secondary);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  margin-bottom: 24px;
}

.data-table th, .data-table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  font-size: 13px;
}

.data-table th {
  background: var(--bg-tertiary);
  font-weight: 600;
  color: var(--text-secondary);
}

.code-block {
  background: var(--bg-primary);
  border: 1px solid var(--border);
  padding: 8px 12px;
  border-radius: 4px;
  font-family: monospace;
  font-size: 12px;
  color: #38bdf8;
  display: flex;
  align-items: center;
  justify-content: space-between;
  word-break: break-all;
}

.btn-copy {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 3px 8px;
  border-radius: 4px;
  font-size: 11px;
  cursor: pointer;
  flex-shrink: 0;
  margin-left: 8px;
}
.btn-copy:hover { background: var(--accent); color: #fff; }

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
  color: var(--text-muted);
  text-align: center;
  gap: 12px;
}

.empty-icon {
  font-size: 48px;
  opacity: 0.5;
}