:root {
  --brand-dark: #0f172a;
  --brand-mid: #1e293b;
  --border: #d6d9dc;
  --surface: #f8fafc;
  --text-muted: #52606d;
  --error: #dc2626;
  --error-bg: #fef2f2;
  color-scheme: light;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
}

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

body {
  margin: 0;
  min-height: 100vh;
  background: #f5f6f7;
  color: #1f2933;
}

/* =================== LOGIN SCREEN =================== */

.login-screen {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: var(--brand-dark);
  padding: 1rem;
}

.login-card {
  background: #ffffff;
  border-radius: 0.75rem;
  padding: 2.25rem 2rem;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.22);
}

.login-brand {
  margin: 0 0 0.15rem;
  font-size: 1.75rem;
  color: var(--brand-dark);
}

.login-subtitle {
  margin: 0 0 1.5rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.login-form {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.login-form button[type="submit"] {
  margin-top: 0.25rem;
  width: 100%;
  justify-content: center;
}

.auth-secondary {
  margin-top: 1.25rem;
  border-top: 1px solid var(--border);
  padding-top: 1rem;
}

.auth-secondary summary {
  cursor: pointer;
  color: var(--text-muted);
  font-size: 0.88rem;
  user-select: none;
  padding: 0.1rem 0;
}

.auth-secondary form {
  margin-top: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

/* =================== APP SHELL =================== */

.app-shell {
  display: grid;
  grid-template-columns: 220px 1fr;
  min-height: 100vh;
}

/* =================== SIDE NAV =================== */

.side-nav {
  background: var(--brand-dark);
  color: #f1f5f9;
  display: flex;
  flex-direction: column;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.nav-brand {
  padding: 1.25rem 1.25rem 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.nav-brand-name {
  font-size: 1.1rem;
  font-weight: 700;
  color: #f1f5f9;
  letter-spacing: -0.01em;
}

.nav-user {
  padding: 0.75rem 1.25rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.nav-user-email {
  display: block;
  font-size: 0.78rem;
  color: #94a3b8;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.nav-role-badge {
  display: inline-block;
  margin-top: 0.35rem;
  padding: 0.15rem 0.5rem;
  border-radius: 0.25rem;
  background: rgba(255, 255, 255, 0.1);
  font-size: 0.73rem;
  color: #e2e8f0;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.nav-links {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 0.5rem 0;
  gap: 0.05rem;
}

.nav-item {
  display: block;
  width: 100%;
  padding: 0.65rem 1.25rem;
  text-align: left;
  background: transparent;
  border: none;
  color: #94a3b8;
  font: inherit;
  font-size: 0.875rem;
  cursor: pointer;
  transition: background 0.12s, color 0.12s;
}

.nav-item:hover {
  background: rgba(255, 255, 255, 0.07);
  color: #f1f5f9;
}

.nav-item.active {
  background: rgba(255, 255, 255, 0.13);
  color: #ffffff;
  font-weight: 600;
}

.nav-footer {
  padding: 1rem 1.25rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.sign-out-btn {
  width: 100%;
  padding: 0.5rem;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.18);
  color: #94a3b8;
  border-radius: 0.4rem;
  font: inherit;
  font-size: 0.84rem;
  cursor: pointer;
  transition: background 0.12s, color 0.12s;
}

.sign-out-btn:hover {
  background: rgba(255, 255, 255, 0.07);
  color: #f1f5f9;
}

/* =================== MAIN CONTENT =================== */

.main-content {
  padding: 1.75rem 2rem;
  overflow-y: auto;
}

.content-section {
  max-width: 920px;
}

.content-section h2 {
  margin: 0 0 1.25rem;
  font-size: 1.3rem;
}

.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.section-header h2 {
  margin: 0;
}

/* =================== FORMS =================== */

.form-panel {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 1.25rem;
  margin-bottom: 1rem;
}

.form-panel h3 {
  margin: 0 0 1rem;
  font-size: 1rem;
  font-weight: 600;
}

.form-grid {
  display: grid;
  gap: 0.75rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  align-items: center;
  margin-top: 0.25rem;
}

.form-hint {
  margin: 0 0 0.75rem;
  color: var(--text-muted);
  font-size: 0.875rem;
}

label {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  font-size: 0.925rem;
  font-weight: 500;
}

input,
select,
textarea {
  font: inherit;
  font-weight: 400;
  padding: 0.5rem 0.65rem;
  border: 1px solid var(--border);
  border-radius: 0.35rem;
  background: #fff;
  color: #1f2933;
}

input:focus,
select:focus {
  outline: 2px solid #3b82f6;
  outline-offset: 1px;
  border-color: #3b82f6;
}

button {
  font: inherit;
  padding: 0.5rem 1rem;
  border-radius: 0.35rem;
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--surface);
  color: #1f2933;
  width: fit-content;
  transition: background 0.12s;
}

button[type="submit"],
.btn-primary {
  background: var(--brand-dark);
  color: #ffffff;
  border-color: var(--brand-dark);
}

button[type="submit"]:hover,
.btn-primary:hover {
  background: var(--brand-mid);
  border-color: var(--brand-mid);
}

.btn-secondary {
  background: var(--surface);
  color: #374151;
  border-color: var(--border);
}

.btn-secondary:hover {
  background: #e2e8f0;
}

.btn-danger {
  background: var(--error);
  color: #fff;
  border-color: var(--error);
}

.btn-danger:hover {
  background: #b91c1c;
  border-color: #b91c1c;
}

/* =================== DATA TABLE =================== */

.data-table {
  width: 100%;
  border-collapse: collapse;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  overflow: hidden;
  font-size: 0.875rem;
}

.data-table th {
  background: var(--surface);
  text-align: left;
  padding: 0.65rem 1rem;
  font-weight: 600;
  color: #374151;
  border-bottom: 1px solid var(--border);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.data-table td {
  padding: 0.7rem 1rem;
  border-bottom: 1px solid #f1f5f9;
  color: #1f2933;
}

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

.data-table tbody tr:hover td {
  background: #f8fafc;
}

/* =================== STATE INDICATORS =================== */

.empty-state {
  padding: 2.5rem 1.25rem;
  text-align: center;
  color: var(--text-muted);
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  font-size: 0.925rem;
}

.loading-state {
  padding: 1.5rem 1.25rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.form-error {
  color: var(--error);
  background: var(--error-bg);
  border: 1px solid #fca5a5;
  border-radius: 0.35rem;
  padding: 0.5rem 0.75rem;
  margin: 0;
  font-size: 0.875rem;
}

/* =================== KPI CARDS =================== */

.kpi-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.kpi-card {
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 0.9rem 1rem;
  background: #ffffff;
}

.kpi-card h3 {
  margin: 0;
  font-size: 0.78rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}

.kpi-card p {
  margin: 0.35rem 0 0;
  font-weight: 600;
  font-size: 1.1rem;
}

/* =================== ACTIVITY LOG =================== */

.response-log {
  margin: 0;
  background: #111827;
  color: #e5e7eb;
  padding: 1rem;
  border-radius: 0.5rem;
  max-height: 600px;
  overflow: auto;
  font-size: 0.78rem;
  line-height: 1.55;
}

/* =================== RESPONSIVE =================== */

@media (max-width: 768px) {
  .app-shell {
    grid-template-columns: 1fr;
    grid-template-rows: auto 1fr;
  }

  .side-nav {
    position: static;
    height: auto;
    flex-direction: row;
    flex-wrap: wrap;
    overflow: visible;
  }

  .nav-brand,
  .nav-user {
    width: 100%;
  }

  .nav-links {
    flex: unset;
    flex-direction: row;
    flex-wrap: wrap;
    width: 100%;
    padding: 0.35rem;
    gap: 0.1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }

  .nav-item {
    padding: 0.5rem 0.85rem;
    width: auto;
    font-size: 0.82rem;
  }

  .nav-footer {
    width: 100%;
    padding: 0.5rem 1rem;
  }

  .sign-out-btn {
    width: auto;
  }

  .main-content {
    padding: 1.25rem;
  }

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

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