/* ============================================================
   AI Agent Transfer Hub - Global Stylesheet
   Pure White Enterprise Theme | PHP 7.4 Compatible
   ============================================================ */

/* ---- CSS Variables ---- */
:root {
    --color-primary: #2563EB;
    --color-primary-dark: #1D4ED8;
    --color-primary-light: #DBEAFE;
    --color-primary-50: #EFF6FF;

    --color-bg: #FFFFFF;
    --color-bg-secondary: #F8FAFC;
    --color-bg-tertiary: #F1F5F9;
    --color-bg-elevated: #FFFFFF;

    --color-text-primary: #0F172A;
    --color-text-secondary: #475569;
    --color-text-tertiary: #94A3B8;
    --color-text-muted: #CBD5E1;

    --color-border: #E2E8F0;
    --color-border-light: #F1F5F9;
    --color-divider: #F1F5F9;

    --color-success: #059669;
    --color-success-bg: #ECFDF5;
    --color-warning: #D97706;
    --color-warning-bg: #FFFBEB;
    --color-danger: #DC2626;
    --color-danger-bg: #FEF2F2;
    --color-info: #2563EB;
    --color-info-bg: #EFF6FF;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 1px 3px rgba(0, 0, 0, 0.08), 0 4px 12px rgba(0, 0, 0, 0.04);
    --shadow-lg: 0 4px 24px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 12px 48px rgba(0, 0, 0, 0.08);

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-full: 9999px;

    --font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', monospace;

    --transition: all 0.2s ease;
    --transition-slow: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);

    --nav-height: 68px;
    --content-max-width: 1280px;
    --section-padding: 100px;
}

/* ---- Reset & Base ---- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: 14px;
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg-secondary);
    min-height: 100vh;
}

.page-wrapper {
    min-height: calc(100vh - 300px);
}

a {
    text-decoration: none;
    color: var(--color-primary);
    transition: var(--transition);
}

a:hover {
    color: var(--color-primary-dark);
}

img {
    max-width: 100%;
    height: auto;
}

button {
    cursor: pointer;
    font-family: inherit;
    border: none;
    background: none;
}

input, textarea, select {
    font-family: inherit;
    font-size: 14px;
}

/* ---- Navigation ---- */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(20px) saturate(1.8);
    -webkit-backdrop-filter: blur(20px) saturate(1.8);
    border-bottom: 1px solid var(--color-border-light);
    z-index: 1000;
}

.nav-container {
    max-width: var(--content-max-width);
    margin: 0 auto;
    padding: 0 32px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none !important;
}

.logo-text {
    font-size: 18px;
    font-weight: 700;
    color: var(--color-text-primary);
    letter-spacing: -0.01em;
}

.nav-menu {
    display: flex;
    align-items: center;
    list-style: none;
    gap: 4px;
}

.nav-menu li a {
    display: block;
    padding: 8px 16px;
    color: var(--color-text-secondary);
    font-size: 14px;
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: var(--transition);
}

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

.nav-menu li a.active {
    color: var(--color-primary);
    background: var(--color-primary-50);
}

.nav-menu li a.admin-link {
    color: var(--color-primary);
    font-weight: 600;
}

.nav-menu li a.btn {
    padding: 8px 20px;
}

.nav-user {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-left: 8px;
    padding-left: 16px;
    border-left: 1px solid var(--color-border);
}

.user-name {
    font-size: 13px;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: 8px;
}

.nav-toggle span {
    display: block;
    width: 20px;
    height: 2px;
    background: var(--color-text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

.admin-sidebar-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: 8px;
    background: none;
    border: none;
    cursor: pointer;
}

.admin-sidebar-toggle span {
    display: block;
    width: 20px;
    height: 2px;
    background: var(--color-text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

/* ---- Buttons ---- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 24px;
    font-size: 14px;
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition-slow);
    border: 1.5px solid transparent;
    white-space: nowrap;
}

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

.btn-primary:hover {
    background: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--color-text-secondary);
    border-color: var(--color-border);
}

.btn-outline:hover {
    background: var(--color-bg-tertiary);
    border-color: var(--color-text-muted);
    color: var(--color-text-primary);
}

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

.btn-danger:hover {
    background: #B91C1C;
    border-color: #B91C1C;
    color: #fff;
}

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

.btn-success:hover {
    background: #047857;
    border-color: #047857;
    color: #fff;
}

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

.btn-secondary:hover {
    background: var(--color-border-light);
    color: var(--color-text-primary);
}

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
    border-color: transparent;
}

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

.btn-sm {
    padding: 6px 16px;
    font-size: 13px;
}

.btn-lg {
    padding: 14px 32px;
    font-size: 15px;
}

.btn-block {
    width: 100%;
}

.btn svg {
    flex-shrink: 0;
}

/* ---- Forms ---- */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    margin-bottom: 6px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text-primary);
}

.form-label .required {
    color: var(--color-danger);
    margin-left: 2px;
}

.form-input {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-bg);
    color: var(--color-text-primary);
    font-size: 14px;
    transition: var(--transition);
    outline: none;
}

.form-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-input::placeholder {
    color: var(--color-text-muted);
}

.form-input:disabled {
    background: var(--color-bg-tertiary);
    cursor: not-allowed;
}

select.form-input {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2394A3B8' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
}

textarea.form-input {
    resize: vertical;
    min-height: 100px;
}

.form-hint {
    margin-top: 4px;
    font-size: 12px;
    color: var(--color-text-tertiary);
}

.form-error {
    margin-top: 4px;
    font-size: 12px;
    color: var(--color-danger);
}

/* ---- Cards ---- */
.card {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-slow);
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card-body {
    padding: 24px;
}

.card-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--color-border-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-text-primary);
}

/* ---- Stat Cards ---- */
.stat-card {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    padding: 24px;
    transition: var(--transition-slow);
}

.stat-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.stat-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 14px;
}

.stat-icon.blue { background: var(--color-primary-50); color: var(--color-primary); }
.stat-icon.green { background: var(--color-success-bg); color: var(--color-success); }
.stat-icon.orange { background: var(--color-warning-bg); color: var(--color-warning); }
.stat-icon.red { background: var(--color-danger-bg); color: var(--color-danger); }
.stat-icon.gray { background: var(--color-bg-tertiary); color: var(--color-text-secondary); }

.stat-value {
    font-size: 26px;
    font-weight: 700;
    color: var(--color-text-primary);
    line-height: 1.2;
    margin-bottom: 4px;
}

.stat-label {
    font-size: 13px;
    color: var(--color-text-tertiary);
    font-weight: 500;
}

.stat-change {
    font-size: 12px;
    font-weight: 600;
    margin-top: 8px;
}

.stat-change.up { color: var(--color-success); }
.stat-change.down { color: var(--color-danger); }

/* ---- Tables ---- */
.data-table-wrapper {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    overflow: hidden;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
}

.data-table thead th {
    padding: 14px 20px;
    text-align: left;
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    background: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    white-space: nowrap;
}

.data-table tbody td {
    padding: 14px 20px;
    font-size: 13px;
    color: var(--color-text-secondary);
    border-bottom: 1px solid var(--color-border-light);
    vertical-align: middle;
}

.data-table tbody tr {
    transition: var(--transition);
}

.data-table tbody tr:hover {
    background: var(--color-bg-secondary);
}

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

/* ---- Badges ---- */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    border-radius: var(--radius-full);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.01em;
}

.badge-success {
    background: var(--color-success-bg);
    color: var(--color-success);
}

.badge-warning {
    background: var(--color-warning-bg);
    color: var(--color-warning);
}

.badge-danger {
    background: var(--color-danger-bg);
    color: var(--color-danger);
}

.badge-info {
    background: var(--color-info-bg);
    color: var(--color-info);
}

.badge-gray {
    background: var(--color-bg-tertiary);
    color: var(--color-text-secondary);
}

/* ---- Alerts ---- */
.alert {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 18px;
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 500;
    margin-bottom: 20px;
}

.alert-success {
    background: var(--color-success-bg);
    color: var(--color-success);
    border: 1px solid #A7F3D0;
}

.alert-error {
    background: var(--color-danger-bg);
    color: var(--color-danger);
    border: 1px solid #FECACA;
}

.alert-warning {
    background: var(--color-warning-bg);
    color: var(--color-warning);
    border: 1px solid #FDE68A;
}

.alert-info {
    background: var(--color-info-bg);
    color: var(--color-info);
    border: 1px solid #BFDBFE;
}

.alert svg {
    flex-shrink: 0;
}

/* ---- Layout Containers ---- */
.container {
    max-width: var(--content-max-width);
    margin: 0 auto;
    padding: 0 32px;
}

.container-sm {
    max-width: 480px;
    margin: 0 auto;
    padding: 0 24px;
}

.container-md {
    max-width: 720px;
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: var(--section-padding) 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    background: var(--color-primary-50);
    color: var(--color-primary);
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    color: var(--color-text-primary);
    line-height: 1.2;
    margin-bottom: 12px;
}

.section-desc {
    font-size: 16px;
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.7;
}

/* ---- Grid System ---- */
.grid {
    display: grid;
    gap: 24px;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-5 { grid-template-columns: repeat(5, 1fr); }

/* ---- Auth Pages (Login/Register) ---- */
.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-secondary) 100%);
}

.auth-card {
    width: 100%;
    max-width: 440px;
    background: var(--color-bg);
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border-light);
    box-shadow: var(--shadow-xl);
    padding: 40px 36px;
}

.auth-logo {
    text-align: center;
    margin-bottom: 32px;
}

.auth-logo svg {
    margin: 0 auto 12px;
    display: block;
}

.auth-logo h1 {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-text-primary);
}

.auth-logo p {
    font-size: 13px;
    color: var(--color-text-tertiary);
    margin-top: 4px;
}

.auth-footer {
    text-align: center;
    margin-top: 24px;
    padding-top: 24px;
    border-top: 1px solid var(--color-border-light);
    font-size: 13px;
    color: var(--color-text-tertiary);
}

.auth-footer a {
    font-weight: 600;
}

/* ---- Dashboard Layout ---- */
.dashboard-page {
    padding-top: calc(var(--nav-height) + 32px);
    padding-bottom: 48px;
}

.page-header {
    margin-bottom: 32px;
}

.page-header h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: 4px;
}

.page-header p {
    font-size: 14px;
    color: var(--color-text-secondary);
}

/* ---- Stat Grid ---- */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-bottom: 32px;
}

/* ---- Chart Cards ---- */
.chart-card {
    background: var(--color-bg-elevated);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    padding: 24px;
    margin-bottom: 24px;
}

.chart-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.chart-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--color-text-primary);
}

.chart-wrapper {
    position: relative;
    height: 280px;
}

.chart-wrapper-sm {
    height: 200px;
}

/* ---- Tabs ---- */
.tabs {
    display: flex;
    gap: 4px;
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md);
    padding: 4px;
    margin-bottom: 24px;
}

.tab-btn {
    padding: 8px 18px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    transition: var(--transition);
    cursor: pointer;
    border: none;
    background: none;
}

.tab-btn:hover {
    color: var(--color-text-primary);
}

.tab-btn.active {
    background: var(--color-bg);
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

/* ---- Pagination ---- */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    margin-top: 24px;
}

.page-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 36px;
    height: 36px;
    padding: 0 10px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text-secondary);
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: var(--transition);
    cursor: pointer;
}

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

.page-btn.active {
    background: var(--color-primary);
    color: #fff;
    border-color: var(--color-primary);
}

.page-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

/* ---- Modal ---- */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.45);
    backdrop-filter: blur(4px);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.modal-overlay.active {
    display: flex;
}

.modal-content {
    background: var(--color-bg);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 520px;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from { opacity: 0; transform: translateY(-20px) scale(0.97); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
    padding: 24px 28px 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-header h3 {
    font-size: 18px;
    font-weight: 700;
}

.modal-close {
    width: 32px;
    height: 32px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-tertiary);
    transition: var(--transition);
    cursor: pointer;
}

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

.modal-body {
    padding: 20px 28px;
}

.modal-footer {
    padding: 0 28px 24px;
    display: flex;
    gap: 10px;
    justify-content: flex-end;
}

/* ---- Model Selector (Checkbox Grid) ---- */
.model-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
    max-height: 320px;
    overflow-y: auto;
    padding: 4px;
}

.model-option {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 12px;
    border-radius: var(--radius-md);
    border: 1.5px solid var(--color-border);
    cursor: pointer;
    transition: var(--transition);
}

.model-option:hover {
    border-color: var(--color-primary);
    background: var(--color-primary-50);
}

.model-option input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--color-primary);
    flex-shrink: 0;
}

.model-option .model-name {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-primary);
    display: block;
}

.model-option .model-desc {
    font-size: 11px;
    color: var(--color-text-tertiary);
    display: block;
}

/* ---- Key Display ---- */
.key-display {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 10px 14px;
    font-family: var(--font-mono);
    font-size: 12px;
}

.key-text {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    color: var(--color-text-secondary);
}

.key-actions {
    display: flex;
    gap: 4px;
    flex-shrink: 0;
}

.icon-btn {
    width: 28px;
    height: 28px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-tertiary);
    background: transparent;
    border: none;
    cursor: pointer;
    transition: var(--transition);
}

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

/* ---- Admin Layout ---- */
.admin-layout {
    display: flex;
    min-height: 100vh;
}

.admin-sidebar {
    width: 260px;
    background: var(--color-bg);
    border-right: 1px solid var(--color-border);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    z-index: 100;
}

.admin-brand {
    padding: 20px 24px;
    border-bottom: 1px solid var(--color-border-light);
    display: flex;
    align-items: center;
    gap: 10px;
}

.admin-brand span {
    font-size: 16px;
    font-weight: 700;
    color: var(--color-text-primary);
}

.admin-nav {
    padding: 16px 12px;
    list-style: none;
}

.admin-nav li {
    margin-bottom: 2px;
}

.admin-nav li a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 14px;
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: var(--transition);
}

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

.admin-nav li a.active {
    background: var(--color-primary-50);
    color: var(--color-primary);
    font-weight: 600;
}

.admin-nav-section {
    padding: 16px 12px 8px 24px;
    font-size: 11px;
    font-weight: 700;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.admin-main {
    flex: 1;
    margin-left: 260px;
    background: var(--color-bg-secondary);
    min-height: 100vh;
}

.admin-header {
    height: 64px;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 32px;
    position: sticky;
    top: 0;
    z-index: 50;
}

.admin-page-title {
    font-size: 18px;
    font-weight: 700;
}

.admin-body {
    padding: 32px;
}

.admin-footer {
    padding: 20px 32px;
    text-align: center;
    font-size: 12px;
    color: var(--color-text-tertiary);
    border-top: 1px solid var(--color-border-light);
}

/* ---- Admin Stats Cards ---- */
.admin-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-bottom: 32px;
}

.admin-stat-card {
    background: var(--color-bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    padding: 24px;
}

.admin-stat-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 12px;
}

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

.admin-stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--color-text-primary);
}

/* ---- Search Bar ---- */
.search-bar {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 24px;
}

.search-input-wrapper {
    flex: 1;
    position: relative;
    max-width: 360px;
}

.search-input-wrapper svg {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-text-muted);
    pointer-events: none;
}

.search-input-wrapper input {
    width: 100%;
    padding: 10px 14px 10px 38px;
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-bg);
    outline: none;
    font-size: 13px;
    transition: var(--transition);
}

.search-input-wrapper input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* ---- Status Dots ---- */
.status-dot {
    display: inline-block;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    margin-right: 6px;
}

.status-dot.online { background: var(--color-success); box-shadow: 0 0 0 2px var(--color-success-bg); }
.status-dot.offline { background: var(--color-danger); box-shadow: 0 0 0 2px var(--color-danger-bg); }
.status-dot.warning { background: var(--color-warning); box-shadow: 0 0 0 2px var(--color-warning-bg); }

/* ---- Empty State ---- */
.empty-state {
    text-align: center;
    padding: 60px 24px;
}

.empty-state svg {
    color: var(--color-text-muted);
    margin-bottom: 16px;
}

.empty-state h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: 6px;
}

.empty-state p {
    font-size: 13px;
    color: var(--color-text-tertiary);
}

/* ---- Tooltip ---- */
.tooltip {
    position: relative;
}

.tooltip::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-6px);
    padding: 4px 10px;
    background: var(--color-text-primary);
    color: #fff;
    font-size: 11px;
    border-radius: var(--radius-sm);
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
}

.tooltip:hover::after {
    opacity: 1;
}

/* ---- Animations ---- */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

.animate-fade-in {
    animation: fadeIn 0.5s ease forwards;
}

.animate-slide-up {
    animation: slideUp 0.6s ease forwards;
}

/* ---- Scrollbar ---- */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--color-text-muted);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-tertiary);
}

/* ---- Selection ---- */
::selection {
    background: var(--color-primary-light);
    color: var(--color-primary-dark);
}

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

@media (max-width: 1024px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-5 { grid-template-columns: repeat(3, 1fr); }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .admin-stats { grid-template-columns: repeat(2, 1fr); }

    .admin-sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s ease;
        z-index: 200;
    }

    .admin-sidebar.open {
        transform: translateX(0);
    }

    .admin-main {
        margin-left: 0;
    }

    .admin-sidebar-toggle {
        display: flex !important;
    }
}

@media (max-width: 768px) {
    :root {
        --section-padding: 60px;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        flex-direction: column;
        padding: 8px 16px;
        gap: 2px;
        box-shadow: var(--shadow-lg);
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-menu li {
        width: 100%;
    }

    .nav-menu li a {
        padding: 12px 16px;
        width: 100%;
    }

    .nav-user {
        border-left: none;
        margin-left: 0;
        padding-left: 0;
        padding-top: 8px;
        border-top: 1px solid var(--color-border);
        flex-direction: column;
        align-items: flex-start;
    }

    .section-title {
        font-size: 26px;
    }

    .grid-2, .grid-3, .grid-4, .grid-5 {
        grid-template-columns: 1fr;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .stat-value {
        font-size: 22px;
    }

    .container {
        padding: 0 20px;
    }

    .chart-wrapper {
        height: 220px;
    }

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

    .auth-card {
        padding: 32px 24px;
    }

    .admin-stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .admin-header {
        padding: 0 20px;
    }

    .admin-body {
        padding: 20px;
    }

    .search-bar {
        flex-direction: column;
        align-items: stretch;
    }

    .search-input-wrapper {
        max-width: none;
    }

    .data-table-wrapper {
        overflow-x: auto;
    }

    .data-table {
        min-width: 700px;
    }
}

@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }

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

    .section-title {
        font-size: 22px;
    }

    .btn-lg {
        padding: 12px 24px;
        font-size: 14px;
    }
}

/* ============================================================
   HOMEPAGE SPECIFIC STYLES
   ============================================================ */

/* Hero Section */
.hero-section {
    padding-top: calc(var(--nav-height) + 80px);
    padding-bottom: var(--section-padding);
    background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-secondary) 100%);
    position: relative;
    overflow: hidden;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: var(--color-primary-50);
    border: 1px solid var(--color-primary-light);
    border-radius: var(--radius-full);
    font-size: 13px;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 24px;
}

.hero-title {
    font-size: 48px;
    font-weight: 800;
    color: var(--color-text-primary);
    line-height: 1.1;
    letter-spacing: -0.02em;
    margin-bottom: 20px;
}

.hero-title .accent {
    color: var(--color-primary);
}

.hero-desc {
    font-size: 17px;
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: 32px;
    max-width: 480px;
}

.hero-actions {
    display: flex;
    gap: 12px;
}

.hero-visual {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-card-visual {
    background: var(--color-bg);
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-xl);
    padding: 32px;
    width: 100%;
    max-width: 440px;
}

.hero-card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--color-border-light);
}

.hero-card-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.hero-card-dot.red { background: #FF5F57; }
.hero-card-dot.yellow { background: #FFBD2E; }
.hero-card-dot.green { background: #28C840; }

.hero-card-title {
    font-size: 13px;
    color: var(--color-text-tertiary);
    font-weight: 500;
}

.code-block {
    background: var(--color-bg-secondary);
    border-radius: var(--radius-md);
    padding: 16px 20px;
    font-family: var(--font-mono);
    font-size: 12px;
    line-height: 1.8;
    color: var(--color-text-secondary);
}

.code-keyword { color: var(--color-primary); font-weight: 600; }
.code-string { color: var(--color-success); }
.code-comment { color: var(--color-text-muted); }

/* Feature Cards */
.feature-section {
    background: var(--color-bg);
}

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

.feature-card {
    padding: 32px;
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-lg);
    transition: var(--transition-slow);
}

.feature-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: var(--color-border);
}

.feature-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon svg {
    color: var(--color-primary);
}

.feature-title {
    font-size: 17px;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: 10px;
}

.feature-desc {
    font-size: 14px;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* Advantages Section */
.advantage-section {
    background: var(--color-bg-secondary);
}

.advantage-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.advantage-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 24px;
    background: var(--color-bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    transition: var(--transition);
}

.advantage-item:hover {
    box-shadow: var(--shadow-md);
}

.advantage-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    background: var(--color-primary-50);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.advantage-icon svg {
    color: var(--color-primary);
}

.advantage-content h3 {
    font-size: 15px;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: 6px;
}

.advantage-content p {
    font-size: 13px;
    color: var(--color-text-secondary);
    line-height: 1.6;
}

/* CTA Section */
.cta-section {
    background: var(--color-bg);
    padding: 80px 0;
}

.cta-card {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    border-radius: var(--radius-xl);
    padding: 60px 40px;
    text-align: center;
    color: #fff;
}

.cta-title {
    font-size: 30px;
    font-weight: 700;
    margin-bottom: 12px;
}

.cta-desc {
    font-size: 15px;
    opacity: 0.85;
    margin-bottom: 28px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.cta-actions .btn {
    background: #fff;
    color: var(--color-primary);
    border-color: #fff;
    font-weight: 700;
}

.cta-actions .btn:hover {
    background: rgba(255,255,255,0.92);
    color: var(--color-primary-dark);
    box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

/* ---- Responsive Homepage ---- */
@media (max-width: 1024px) {
    .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-title {
        font-size: 38px;
    }

    .hero-desc {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-visual {
        order: -1;
    }

    .hero-card-visual {
        max-width: 100%;
    }
}

@media (max-width: 768px) {
    .hero-section {
        padding-top: calc(var(--nav-height) + 40px);
    }

    .hero-title {
        font-size: 30px;
    }

    .hero-desc {
        font-size: 15px;
    }

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

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

    .cta-card {
        padding: 40px 24px;
    }

    .cta-title {
        font-size: 22px;
    }
}