:root,
:root.light {
    --ds-space-0: 0;
    --ds-space-1: 0.25rem;
    --ds-space-2: 0.5rem;
    --ds-space-3: 0.75rem;
    --ds-space-4: 1rem;
    --ds-space-5: 1.25rem;
    --ds-space-6: 1.5rem;
    --ds-space-7: 1.75rem;
    --ds-space-8: 2rem;
    --ds-space-10: 2.5rem;
    --ds-space-12: 3rem;

    --ds-text-xs: 0.75rem;
    --ds-text-sm: 0.875rem;
    --ds-text-md: 1rem;
    --ds-text-lg: 1.125rem;
    --ds-text-xl: 1.25rem;
    --ds-text-2xl: 1.5rem;
    --ds-text-3xl: 1.875rem;

    --ds-radius-sm: 0.5rem;
    --ds-radius-md: 0.75rem;
    --ds-radius-lg: 1rem;
    --ds-radius-xl: 1.25rem;
    --ds-radius-pill: 999px;

    --ds-shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.08);
    --ds-shadow-md: 0 6px 14px rgba(15, 23, 42, 0.09);
    --ds-shadow-lg: 0 14px 34px rgba(15, 23, 42, 0.12);
    --ds-shadow-xl: 0 24px 60px rgba(15, 23, 42, 0.15);

    --ds-focus-ring: 0 0 0 3px color-mix(in srgb, var(--brand-primary) 32%, transparent);
    --ds-surface-0: color-mix(in srgb, var(--_surface) 96%, white);
    --ds-surface-1: color-mix(in srgb, var(--_surface) 92%, white);
    --ds-surface-2: color-mix(in srgb, var(--_surface) 88%, white);
    --ds-border-strong: color-mix(in srgb, var(--brand-neutral) 32%, transparent);
    --ds-border-soft: color-mix(in srgb, var(--brand-neutral) 20%, transparent);
    --ds-text-primary: var(--_text);
    --ds-text-secondary: color-mix(in srgb, var(--_text) 74%, var(--_bg));
    --ds-danger: #b91c1c;
    --ds-touch-target: 44px;
}

:root.dark {
    --ds-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
    --ds-shadow-md: 0 8px 20px rgba(0, 0, 0, 0.42);
    --ds-shadow-lg: 0 16px 34px rgba(0, 0, 0, 0.48);
    --ds-shadow-xl: 0 26px 60px rgba(0, 0, 0, 0.55);
    --ds-surface-0: color-mix(in srgb, var(--_surface) 96%, black);
    --ds-surface-1: color-mix(in srgb, var(--_surface) 92%, black);
    --ds-surface-2: color-mix(in srgb, var(--_surface) 88%, black);
    --ds-text-secondary: color-mix(in srgb, var(--_text) 80%, var(--_bg));
}

html {
    font-size: 16px;
}

body {
    color: var(--ds-text-primary);
    text-rendering: optimizeLegibility;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    color: var(--ds-text-primary);
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(var(--ds-text-2xl), 4vw, var(--ds-text-3xl));
}

h2 {
    font-size: clamp(var(--ds-text-xl), 2.5vw, var(--ds-text-2xl));
}

h3 {
    font-size: clamp(var(--ds-text-lg), 2vw, var(--ds-text-xl));
}

p,
li,
dd,
dt {
    color: var(--ds-text-secondary);
    font-size: var(--ds-text-md);
    line-height: 1.55;
}

small {
    font-size: var(--ds-text-xs);
}

a,
button,
input,
select,
textarea,
[role="button"] {
    touch-action: manipulation;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
[role="button"]:focus-visible {
    outline: none;
    box-shadow: var(--ds-focus-ring);
}

button,
.btn-brand,
.btn-outline-brand,
.btn-accent,
.admin-btn {
    min-height: var(--ds-touch-target);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="search"],
input[type="number"],
select,
textarea,
.admin-input,
.admin-select {
    min-height: var(--ds-touch-target);
    border-radius: var(--ds-radius-md);
}

.app-content-shell {
    width: 100%;
    padding-top: var(--ds-space-4);
    padding-bottom: var(--ds-space-6);
}

.app-main-region {
    min-width: 0;
}

.app-main-card {
    border-radius: var(--ds-radius-xl);
    border: 1px solid var(--ds-border-soft);
    background: var(--ds-surface-1);
    box-shadow: var(--ds-shadow-md);
    min-width: 0;
}

.app-toast-stack {
    width: min(20rem, calc(100vw - 1rem));
    right: 0.5rem;
    bottom: 0.5rem;
}

.app-flag-inline {
    display: inline-block;
    margin: 0 0.25rem;
    vertical-align: middle;
    border-radius: 2px;
    box-shadow: 0 0 0 1px rgba(148, 163, 184, 0.45);
}

.app-flag-inline--mr {
    margin-right: 0.35rem;
    margin-left: 0;
}

.btn-brand,
.btn-accent,
.btn-outline-brand {
    border-radius: var(--ds-radius-pill);
    font-weight: 700;
}

.btn-outline-brand {
    border-width: 1px;
}

.admin-btn {
    border-radius: var(--ds-radius-md);
    font-size: var(--ds-text-sm);
    font-weight: 700;
}

.admin-btn--outline {
    background: var(--ds-surface-0);
}

.admin-btn--danger {
    color: var(--ds-danger);
}

.admin-btn--ghost {
    border-color: transparent;
    background: transparent;
}

.admin-btn:hover,
.admin-btn:active,
.btn-brand:hover,
.btn-outline-brand:hover,
.btn-accent:hover {
    transform: none;
}

.admin-filters {
    align-items: end;
    gap: var(--ds-space-3);
}

.admin-field {
    min-height: var(--ds-touch-target);
}

.admin-field-label {
    color: var(--ds-text-secondary);
}

.admin-input,
.admin-select {
    border-color: var(--ds-border-strong);
    background: var(--ds-surface-0);
    color: var(--ds-text-primary);
}

.admin-input:focus,
.admin-select:focus {
    box-shadow: var(--ds-focus-ring);
}

.app-filter-disclosure {
    border: 1px solid var(--ds-border-soft);
    border-radius: var(--ds-radius-lg);
    background: var(--ds-surface-0);
}

.app-filter-disclosure > summary {
    cursor: pointer;
    list-style: none;
}

.app-filter-disclosure > summary::-webkit-details-marker {
    display: none;
}

.app-filter-disclosure__toggle {
    display: inline-flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--ds-space-3);
    width: 100%;
    min-height: var(--ds-touch-target);
    padding: var(--ds-space-3) var(--ds-space-4);
    color: var(--ds-text-primary);
    font-weight: 700;
    font-size: var(--ds-text-sm);
}

.app-filter-disclosure__toggle::after {
    content: "Show";
    font-size: var(--ds-text-xs);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--ds-text-secondary);
}

.app-filter-disclosure[open] .app-filter-disclosure__toggle::after {
    content: "Hide";
}

.app-filter-disclosure__body {
    padding: var(--ds-space-3);
    border-top: 1px solid var(--ds-border-soft);
}

.admin-table-wrap {
    border-radius: var(--ds-radius-lg);
    box-shadow: var(--ds-shadow-sm);
}

.admin-table {
    font-size: var(--ds-text-sm);
}

.admin-table-head-row {
    font-size: 0.68rem;
    letter-spacing: 0.1em;
}

.admin-cell {
    padding: var(--ds-space-3) var(--ds-space-4);
}

.admin-table-empty {
    color: var(--ds-text-secondary);
}

.admin-actions {
    gap: var(--ds-space-2);
}

.admin-pagination,
.app-pagination {
    margin-top: var(--ds-space-4);
}

.app-pagination__link {
    min-height: var(--ds-touch-target);
}

.dash-kpi-card,
.dash-support-metric,
.dash-focus-card,
.dash-card,
.admin-panel,
.admin-stat,
.admin-location-stat,
.admin-location-chart-card {
    border-radius: var(--ds-radius-lg);
}

/* >= 480px */
@media (min-width: 480px) {
    .app-content-shell {
        padding-top: var(--ds-space-5);
        padding-bottom: var(--ds-space-8);
    }
}

/* < 768px: mobile-first structural UX */
@media (max-width: 767px) {
    .site-header-inner {
        padding: var(--ds-space-3) var(--ds-space-4);
        gap: var(--ds-space-3);
    }

    .app-content-shell {
        padding-inline: var(--ds-space-2);
        padding-top: var(--ds-space-3);
        padding-bottom: var(--ds-space-5);
    }

    .app-main-card {
        padding: var(--ds-space-3) !important;
        border-radius: var(--ds-radius-lg);
        min-height: auto !important;
    }

    .admin-security-shell {
        padding: var(--ds-space-4) !important;
        border-radius: var(--ds-radius-lg) !important;
    }

    .admin-panel-body {
        padding: var(--ds-space-3) !important;
        gap: var(--ds-space-3) !important;
    }

    .admin-security-content,
    .admin-section {
        gap: var(--ds-space-4) !important;
    }

    .admin-security-stats,
    .admin-location-stats,
    .admin-location-chart-grid,
    .dash-support-grid,
    .dash-kpi {
        grid-template-columns: 1fr !important;
    }

    .admin-device-analytics {
        grid-template-columns: 1fr !important;
        padding: var(--ds-space-3);
    }

    .admin-section-header {
        align-items: flex-start;
        gap: var(--ds-space-3);
    }

    .admin-actions {
        justify-content: flex-start;
        width: 100%;
    }

    .support-audit-actions {
        width: 100%;
        justify-content: flex-start;
        padding: var(--ds-space-2);
    }

    .support-audit-actions .admin-btn {
        flex: 1 1 calc(50% - var(--ds-space-2));
        min-width: 0;
    }

    .admin-filters {
        display: grid;
        grid-template-columns: 1fr;
        align-items: stretch;
        width: 100%;
    }

    .admin-field--search,
    .admin-field--inline,
    .admin-field--toggle {
        width: 100%;
        max-width: 100%;
    }

    .admin-field--inline {
        display: grid;
        gap: var(--ds-space-1);
    }

    .admin-field--toggle {
        padding-inline: var(--ds-space-1);
    }

    .admin-filters .admin-btn {
        width: 100%;
    }

    .app-filter-disclosure {
        overflow: hidden;
    }

    .app-filter-disclosure__body {
        padding: var(--ds-space-3);
    }

    .admin-location-table-tabs {
        width: 100%;
        border-radius: var(--ds-radius-md);
    }

    .admin-location-table-tab {
        flex: 1 1 100%;
        min-height: var(--ds-touch-target);
        text-align: center;
    }

    .admin-table-wrap {
        border: none;
        background: transparent;
        overflow: visible;
        box-shadow: none;
    }

    .admin-table,
    .admin-table tbody {
        display: block;
    }

    .admin-table thead {
        display: none;
    }

    .admin-table-body {
        display: grid;
        gap: var(--ds-space-3);
    }

    .admin-table-row {
        display: block;
        border: 1px solid var(--ds-border-soft);
        border-radius: var(--ds-radius-lg);
        background: var(--ds-surface-1);
        box-shadow: var(--ds-shadow-sm);
        overflow: hidden;
    }

    .admin-table-row .admin-cell {
        display: grid;
        grid-template-columns: minmax(7.25rem, 42%) minmax(0, 1fr);
        align-items: start;
        gap: var(--ds-space-2);
        border-bottom: 1px dashed color-mix(in srgb, var(--ds-border-soft) 92%, transparent);
        padding: var(--ds-space-3);
        text-align: left !important;
    }

    .admin-table-row .admin-cell:last-child {
        border-bottom: none;
    }

    .admin-table-row .admin-cell::before {
        content: attr(data-label);
        color: var(--ds-text-secondary);
        font-size: 0.68rem;
        font-weight: 700;
        letter-spacing: 0.08em;
        text-transform: uppercase;
        line-height: 1.35;
        padding-top: 0.2rem;
    }

    .admin-table-row .admin-cell:not([data-label])::before {
        content: "";
    }

    .admin-cell--actions {
        grid-template-columns: 1fr !important;
    }

    .admin-cell--actions::before {
        margin-bottom: var(--ds-space-1);
    }

    .admin-cell--actions .admin-actions {
        width: 100%;
        justify-content: flex-start;
    }

    .admin-cell--actions .admin-actions form,
    .admin-cell--actions .admin-actions .admin-btn {
        width: 100%;
    }

    .admin-table-empty {
        display: block;
        padding: var(--ds-space-6) var(--ds-space-4);
        border: 1px dashed var(--ds-border-soft);
        border-radius: var(--ds-radius-lg);
        background: var(--ds-surface-0);
        text-align: center;
    }

    .app-pagination {
        gap: var(--ds-space-2);
    }

    .app-pagination__list {
        width: 100%;
        justify-content: center;
    }
}

/* >= 768px */
@media (min-width: 768px) {
    .app-content-shell {
        padding-top: var(--ds-space-6);
        padding-bottom: var(--ds-space-10);
    }

    .app-filter-disclosure {
        border: none;
        background: transparent;
    }

    .app-filter-disclosure > summary {
        display: none;
    }

    .app-filter-disclosure:not([open]) > .app-filter-disclosure__body {
        display: block;
    }

    .app-filter-disclosure__body {
        border-top: none;
        padding: 0;
    }
}

/* >= 1024px */
@media (min-width: 1024px) {
    .app-content-shell {
        padding-inline: var(--ds-space-6);
    }

    .app-main-card {
        padding: var(--ds-space-6) !important;
    }

    .admin-security-shell {
        border-radius: var(--ds-radius-xl);
    }
}

/* >= 1440px */
@media (min-width: 1440px) {
    .app-content-shell {
        padding-inline: var(--ds-space-8);
    }

    .admin-panel-body {
        padding: var(--ds-space-6);
    }
}