:root {
  --bg-primary: #f8fafc;
  --bg-surface: #ffffff;
  --bg-subtle: #f1f5f9;
  --border-subtle: #e2e8f0;
  --border-focus: #94a3b8;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-subtle: #94a3b8;
  --accent: #1e293b;
  --accent-hover: #0f172a;
  --accent-text: #ffffff;
  --status-success-bg: #ecfdf5;
  --status-success-text: #065f46;
  --status-success-border: #a7f3d0;
  --status-warning-bg: #fffbeb;
  --status-warning-text: #92400e;
  --status-warning-border: #fde68a;
  --status-error-bg: #fef2f2;
  --status-error-text: #991b1b;
  --status-error-border: #fecaca;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.5;
  font-size: 14px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Layout */
.app-container {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  width: 250px;
  background-color: var(--bg-surface);
  border-right: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  padding: 24px 16px;
}

.brand {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-main);
  padding: 0 12px 24px 12px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 16px;
}

.brand span {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-muted);
  display: block;
  margin-top: 2px;
}

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

.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--radius-md);
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.15s ease;
}

.nav-link svg {
  width: 18px;
  height: 18px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
}

.nav-link:hover {
  background-color: var(--bg-subtle);
  color: var(--text-main);
}

.nav-link.active {
  background-color: var(--bg-subtle);
  color: var(--text-main);
  font-weight: 600;
}

.sidebar-footer {
  margin-top: auto;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
  font-size: 12px;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.main-content {
  flex: 1;
  padding: 32px 40px;
  max-width: 1280px;
  margin: 0 auto;
  width: 100%;
}

.page-header {
  margin-bottom: 28px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.page-title {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-main);
}

.page-subtitle {
  color: var(--text-muted);
  font-size: 14px;
  margin-top: 4px;
}

/* Cards & Grid */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.card-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 24px;
}

.stat-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.stat-label {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

.stat-value {
  font-size: 24px;
  font-weight: 700;
  color: var(--text-main);
  margin-top: 6px;
  letter-spacing: -0.02em;
}

.stat-desc {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* Tables */
.table-wrapper {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 13px;
}

th {
  background-color: var(--bg-subtle);
  color: var(--text-muted);
  font-weight: 600;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border-subtle);
}

td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-main);
}

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

tr:hover td {
  background-color: #fafbfc;
}

/* Badges & Status */
.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 9999px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.badge-success {
  background-color: var(--status-success-bg);
  color: var(--status-success-text);
  border: 1px solid var(--status-success-border);
}

.badge-warning {
  background-color: var(--status-warning-bg);
  color: var(--status-warning-text);
  border: 1px solid var(--status-warning-border);
}

.badge-error {
  background-color: var(--status-error-bg);
  color: var(--status-error-text);
  border: 1px solid var(--status-error-border);
}

.badge-neutral {
  background-color: var(--bg-subtle);
  color: var(--text-muted);
  border: 1px solid var(--border-subtle);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: var(--radius-md);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.15s ease;
  text-decoration: none;
  font-family: inherit;
}

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

.btn-primary:hover {
  background-color: var(--accent-hover);
}

.btn-secondary {
  background-color: var(--bg-surface);
  color: var(--text-main);
  border-color: var(--border-subtle);
}

.btn-secondary:hover {
  background-color: var(--bg-subtle);
}

.btn-danger {
  background-color: var(--bg-surface);
  color: var(--status-error-text);
  border-color: var(--status-error-border);
}

.btn-danger:hover {
  background-color: var(--status-error-bg);
}

.btn-sm {
  padding: 4px 8px;
  font-size: 12px;
}

/* Forms */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-main);
  margin-bottom: 6px;
}

.form-input {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  font-size: 13px;
  font-family: inherit;
  color: var(--text-main);
  background-color: var(--bg-surface);
}

.form-input:focus {
  outline: none;
  border-color: var(--border-focus);
}

/* Upload dropzone */
.dropzone {
  border: 2px dashed var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 40px 20px;
  text-align: center;
  background-color: var(--bg-subtle);
  cursor: pointer;
  transition: border-color 0.15s ease;
}

.dropzone:hover {
  border-color: var(--border-focus);
}

.dropzone-icon {
  width: 36px;
  height: 36px;
  margin: 0 auto 12px auto;
  stroke: var(--text-muted);
}

/* Login Page Layout */
.login-body {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background-color: var(--bg-primary);
}

.login-card {
  width: 100%;
  max-width: 400px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-md);
}