:root {
    --app-bg: #f3f5fb;
    --app-bg-accent-1: rgba(99, 102, 241, 0.08);
    --app-bg-accent-2: rgba(14, 165, 233, 0.06);
    --app-surface: rgba(255, 255, 255, 0.86);
    --app-surface-strong: #ffffff;
    --app-surface-soft: #f8fbff;
    --app-border: rgba(226, 232, 240, 0.95);
    --app-border-strong: rgba(203, 213, 225, 0.95);
    --app-text: #0f172a;
    --app-text-soft: #475569;
    --app-text-faint: #94a3b8;

    --app-primary: #315efb;
    --app-primary-hover: #2348d9;
    --app-primary-soft: rgba(49, 94, 251, 0.10);

    --app-success: #16a34a;
    --app-danger: #dc2626;
    --app-warning: #ca8a04;

    --app-shadow-sm: 0 8px 24px rgba(15, 23, 42, 0.05);
    --app-shadow-md: 0 18px 40px rgba(15, 23, 42, 0.08);
    --app-shadow-lg: 0 26px 60px rgba(15, 23, 42, 0.12);

    --app-radius-sm: 12px;
    --app-radius-md: 18px;
    --app-radius-lg: 24px;

    --app-admin-bg: #111827;
    --app-admin-bg-soft: #1e293b;
    --app-admin-border: rgba(148, 163, 184, 0.18);
    --app-admin-text: #f8fafc;
    --app-admin-text-soft: rgba(226, 232, 240, 0.78);
    --app-admin-badge-bg: rgba(96, 165, 250, 0.16);
    --app-admin-badge-border: rgba(147, 197, 253, 0.28);
    --app-admin-badge-text: #dbeafe;
}

html,
body {
    background:
        radial-gradient(circle at top left, var(--app-bg-accent-1), transparent 28%),
        radial-gradient(circle at top right, var(--app-bg-accent-2), transparent 24%),
        linear-gradient(180deg, #f8fbff 0%, var(--app-bg) 100%);
    color: var(--app-text);
    font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    min-height: 100vh;
}

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

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

/* Navbar */
.navbar {
    min-height: 74px;
    background: rgba(255, 255, 255, 0.72) !important;
    backdrop-filter: saturate(180%) blur(18px);
    -webkit-backdrop-filter: saturate(180%) blur(18px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.85) !important;
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.04);
}

.navbar-admin {
    background:
        linear-gradient(135deg, rgba(15, 23, 42, 0.97) 0%, rgba(30, 41, 59, 0.98) 55%, rgba(36, 52, 71, 0.98) 100%) !important;
    border-bottom: 1px solid var(--app-admin-border) !important;
    box-shadow: 0 16px 40px rgba(2, 6, 23, 0.28);
}

.navbar-admin,
.navbar-admin .app-brand,
.navbar-admin .nav-user-name,
.navbar-admin .nav-user-meta,
.navbar-admin .nav-user-separator {
    color: var(--app-admin-text);
}

.navbar-admin .nav-user-meta,
.navbar-admin .app-brand-subtitle {
    color: var(--app-admin-text-soft);
}

.navbar-admin .btn-outline-secondary {
    color: var(--app-admin-text);
    border-color: rgba(226, 232, 240, 0.24);
    background: rgba(255, 255, 255, 0.04);
}

.navbar-admin .btn-outline-secondary:hover {
    color: var(--app-admin-text);
    border-color: rgba(226, 232, 240, 0.36);
    background: rgba(255, 255, 255, 0.09);
}

.app-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.85rem;
    font-weight: 700;
    color: var(--app-text);
    letter-spacing: -0.03em;
}

.app-brand img {
    display: block;
}

.app-brand-text {
    display: flex;
    flex-direction: column;
    gap: 0.08rem;
    min-width: 0;
}

.app-brand-title {
    font-size: 1rem;
    line-height: 1.1;
    font-weight: 760;
    color: inherit;
}

.app-brand-subtitle {
    font-size: 0.77rem;
    line-height: 1.15;
    color: var(--app-text-soft);
    font-weight: 500;
    letter-spacing: -0.01em;
}

.nav-user {
    display: inline-flex;
    align-items: center;
    gap: 0.85rem;
}

.nav-user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 999px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(180deg, rgba(49, 94, 251, 0.12), rgba(49, 94, 251, 0.07));
    color: var(--app-primary);
    border: 1px solid rgba(49, 94, 251, 0.12);
    font-size: 0.95rem;
    flex: 0 0 auto;
}

.navbar-admin .nav-user-avatar {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.14);
    color: var(--app-admin-text);
}

.nav-user-text {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    min-width: 0;
}

.nav-user-name-row {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-width: 0;
}

.nav-user-name {
    font-size: 0.93rem;
    line-height: 1.15;
    font-weight: 720;
    color: var(--app-text);
    max-width: 240px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.nav-user-meta {
    font-size: 0.78rem;
    line-height: 1.15;
    color: var(--app-text-soft);
    font-weight: 500;
    max-width: 260px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.nav-user-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 24px;
    padding: 0.2rem 0.55rem;
    border-radius: 999px;
    background: rgba(49, 94, 251, 0.08);
    border: 1px solid rgba(49, 94, 251, 0.12);
    color: var(--app-primary);
    font-size: 0.7rem;
    line-height: 1;
    font-weight: 750;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.navbar-admin .nav-user-badge {
    background: var(--app-admin-badge-bg);
    border-color: var(--app-admin-badge-border);
    color: var(--app-admin-badge-text);
}

.nav-user-separator {
    width: 1px;
    align-self: stretch;
    background: rgba(148, 163, 184, 0.28);
}

/* Layout */
.app-shell {
    padding-top: 2rem;
    padding-bottom: 2rem;
}

.app-page-header {
    margin-bottom: 1.5rem;
}

.app-page-title {
    margin: 0;
    font-size: 1.9rem;
    line-height: 1.05;
    font-weight: 750;
    letter-spacing: -0.05em;
    color: var(--app-text);
}

.app-page-subtitle {
    margin-top: 0.55rem;
    color: var(--app-text-soft);
    font-size: 0.98rem;
}

/* Cards */
.card {
    border: 1px solid var(--app-border);
    border-radius: var(--app-radius-lg);
    box-shadow: var(--app-shadow-sm);
    background: var(--app-surface);
}

.card.shadow-sm,
.card.shadow {
    box-shadow: var(--app-shadow-md) !important;
}

.card-header {
    background: transparent;
    border-bottom: 1px solid var(--app-border);
    padding: 1rem 1.25rem;
    border-top-left-radius: var(--app-radius-lg) !important;
    border-top-right-radius: var(--app-radius-lg) !important;
}

.card-body {
    padding: 1.35rem;
}

.app-card-soft {
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.95) 0%, rgba(248, 251, 255, 0.92) 100%);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

.app-card-soft:hover {
    box-shadow: var(--app-shadow-md);
    transition: box-shadow 0.22s ease, transform 0.22s ease;
}

#ebookList > .btn {
    background: rgba(255, 255, 255, 0.72);
    border: 1px solid var(--app-border);
    border-radius: 18px;
}

#ebookList > .btn:hover {
    border-color: rgba(49, 94, 251, 0.22);
    background: rgba(255, 255, 255, 0.96);
    transform: translateY(-1px);
}

#ebookList > .btn.border-primary {
    border-color: rgba(49, 94, 251, 0.45) !important;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.98), rgba(237, 244, 255, 0.95)) !important;
    box-shadow: 0 14px 32px rgba(49, 94, 251, 0.10);
}

#ebookList.admin-mode > .btn {
    padding: 0.8rem 0.9rem !important;
}

#ebookList.admin-mode .fw-semibold.text-truncate {
    font-size: 0.93rem;
}

#ebookList.admin-mode .small {
    line-height: 1.2;
}

.ebook-owner {
    margin-top: 0.35rem;
    padding-top: 0.35rem;
    border-top: 1px dashed rgba(148, 163, 184, 0.22);
}

.ebook-owner-name {
    display: block;
    color: var(--app-text);
    font-size: 0.8rem;
    font-weight: 670;
    line-height: 1.2;
}

.ebook-owner-meta {
    display: block;
    color: var(--app-text-soft);
    font-size: 0.76rem;
    line-height: 1.2;
    margin-top: 0.12rem;
}

/* KPI cards */
.kpi-card {
    border: 1px solid var(--app-border);
    border-radius: 22px;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.94), rgba(248, 251, 255, 0.90));
    box-shadow: var(--app-shadow-sm);
    padding: 1.15rem 1.15rem 1rem;
    height: 100%;
}

.kpi-label {
    font-size: 0.84rem;
    color: var(--app-text-soft);
    margin-bottom: 0.55rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.kpi-value {
    font-size: 2.1rem;
    line-height: 1;
    letter-spacing: -0.05em;
    font-weight: 760;
    color: var(--app-text);
}

.kpi-meta {
    margin-top: 0.55rem;
    font-size: 0.82rem;
    color: var(--app-text-faint);
}

/* Buttons */
.btn {
    border-radius: 999px;
    font-weight: 650;
    transition: all 0.18s ease;
    box-shadow: none !important;
}

.btn-lg {
    min-height: 52px;
    padding-left: 1rem;
    padding-right: 1rem;
}

.btn-primary {
    background: linear-gradient(180deg, #3d6bff 0%, #315efb 100%);
    border-color: #315efb;
}

.btn-primary:hover,
.btn-primary:focus {
    background: linear-gradient(180deg, #345ff0 0%, #2348d9 100%);
    border-color: #2348d9;
    transform: translateY(-1px);
}

.btn-outline-primary {
    border-color: rgba(49, 94, 251, 0.35);
    color: var(--app-primary);
    background: rgba(255, 255, 255, 0.78);
}

.btn-outline-primary:hover,
.btn-outline-primary:focus {
    border-color: rgba(49, 94, 251, 0.6);
    color: var(--app-primary-hover);
    background: rgba(49, 94, 251, 0.05);
}

.btn-outline-secondary {
    border-color: var(--app-border-strong);
    color: var(--app-text-soft);
    background: rgba(255, 255, 255, 0.8);
}

.btn-outline-secondary:hover {
    background: #f8fafc;
    color: var(--app-text);
    border-color: var(--app-border-strong);
}

/* Forms */
.form-label {
    font-size: 0.92rem;
    font-weight: 650;
    color: var(--app-text);
    margin-bottom: 0.45rem;
}

.form-control,
.form-select {
    border-radius: 16px;
    border: 1px solid var(--app-border);
    min-height: 48px;
    color: var(--app-text);
    background-color: rgba(255, 255, 255, 0.86);
    box-shadow: none;
}

.form-control-lg,
.form-select-lg {
    min-height: 54px;
    font-size: 1rem;
    border-radius: 18px;
}

.form-control::placeholder {
    color: #94a3b8;
}

.form-control:focus,
.form-select:focus {
    border-color: rgba(49, 94, 251, 0.38);
    box-shadow: 0 0 0 5px rgba(49, 94, 251, 0.08);
}

/* Login */
.auth-page {
    min-height: 100vh;
    background:
        radial-gradient(circle at top left, rgba(49, 94, 251, 0.10), transparent 28%),
        radial-gradient(circle at bottom right, rgba(14, 165, 233, 0.08), transparent 30%),
        var(--app-bg);
}

.auth-wrap {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.5rem;
}

.auth-card {
    width: 100%;
    max-width: 440px;
    border: 1px solid rgba(226, 232, 240, 0.95);
    border-radius: 28px;
    background: rgba(255, 255, 255, 0.84);
    box-shadow: var(--app-shadow-lg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
}

.auth-card .card-body {
    padding: 1.6rem;
}

.auth-logo {
    margin-bottom: 1.25rem;
    text-align: center;
}

.auth-title {
    font-size: 1.45rem;
    line-height: 1.16;
    font-weight: 760;
    text-align: center;
    letter-spacing: -0.04em;
    margin-bottom: 0.5rem;
    color: var(--app-text);
}

.auth-subtitle {
    color: var(--app-text-soft);
    text-align: center;
    font-size: 0.95rem;
    margin-bottom: 1.25rem;
}

/* Alerts */
.alert {
    border: 1px solid transparent;
    border-radius: 16px;
    font-size: 0.93rem;
    padding: 0.85rem 1rem;
}

.alert-danger {
    color: #991b1b;
    background: #fef2f2;
    border-color: #fecaca;
}

.alert-success {
    color: #166534;
    background: #f0fdf4;
    border-color: #bbf7d0;
}

.alert-warning {
    color: #92400e;
    background: #fffbeb;
    border-color: #fde68a;
}

.alert-info {
    color: #1e40af;
    background: #eff6ff;
    border-color: #bfdbfe;
}

/* Empty state */
.empty-state {
    text-align: center;
    padding: 2.5rem 1.25rem;
    color: var(--app-text-soft);
}

.empty-state-title {
    font-weight: 700;
    color: var(--app-text);
    margin-bottom: 0.4rem;
}

.empty-state-text {
    margin: 0;
    font-size: 0.95rem;
}

/* Dashboard */
.ebook-cover-main {
    width: 120px;
    max-width: 100%;
    border-radius: 18px;
}

.chart-wrap-lg {
    height: 420px;
}

.ebook-cover-thumb {
    width: 44px;
    height: 60px;
    object-fit: cover;
    border-radius: 12px;
}

.ebook-cover-empty {
    width: 44px;
    height: 60px;
    font-size: 12px;
    border-radius: 12px;
}

.latest-rank-col {
    width: 120px;
}

.latest-status-col {
    width: 140px;
}

.badge.text-bg-warning {
    background: linear-gradient(180deg, #facc15 0%, #eab308 100%) !important;
    color: #422006 !important;
    border-radius: 999px;
    font-weight: 700;
    padding: 0.5rem 0.7rem;
}

.table {
    --bs-table-bg: transparent;
}

.table thead th {
    color: var(--app-text-soft);
    font-size: 0.82rem;
    font-weight: 700;
    border-bottom-color: rgba(226, 232, 240, 0.9);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.table td {
    vertical-align: middle;
    border-bottom-color: rgba(226, 232, 240, 0.72);
}

canvas#rankingChart {
    filter: saturate(1.05);
}

/* Mobile ebook picker */
.mobile-picker-toggle {
    width: 100%;
    border: 1px solid var(--app-border);
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(248, 251, 255, 0.92));
    border-radius: 20px;
    padding: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.85rem;
    text-align: left;
    color: var(--app-text);
    box-shadow: var(--app-shadow-sm);
}

.mobile-picker-toggle.is-open {
    border-color: rgba(49, 94, 251, 0.35);
    box-shadow: 0 14px 34px rgba(49, 94, 251, 0.10);
}

.mobile-picker-toggle-media {
    flex: 0 0 auto;
}

.mobile-picker-cover,
.mobile-picker-item-cover {
    width: 46px;
    height: 62px;
    object-fit: cover;
    border-radius: 12px;
    background: #eef2f7;
}

.mobile-picker-cover-fallback,
.mobile-picker-item-cover-fallback {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    color: var(--app-text-soft);
    text-align: center;
    padding: 0.25rem;
}

.mobile-picker-toggle-body,
.mobile-picker-item-body {
    min-width: 0;
    flex: 1 1 auto;
}

.mobile-picker-title,
.mobile-picker-item-title {
    font-size: 0.96rem;
    font-weight: 700;
    line-height: 1.2;
    color: var(--app-text);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.mobile-picker-meta,
.mobile-picker-item-meta {
    font-size: 0.8rem;
    color: var(--app-text-soft);
    margin-top: 0.2rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.mobile-picker-chevron {
    flex: 0 0 auto;
    font-size: 1rem;
    color: var(--app-text-soft);
}

.mobile-picker-menu {
    margin-top: 0.8rem;
    display: flex;
    flex-direction: column;
    gap: 0.65rem;
}

.mobile-picker-item {
    width: 100%;
    border: 1px solid var(--app-border);
    background: rgba(255, 255, 255, 0.88);
    border-radius: 18px;
    padding: 0.8rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-align: left;
    color: var(--app-text);
}

.mobile-picker-item.is-selected {
    border-color: rgba(49, 94, 251, 0.42);
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.98), rgba(237, 244, 255, 0.95));
    box-shadow: 0 14px 28px rgba(49, 94, 251, 0.10);
}

.mobile-picker-item-badge {
    flex: 0 0 auto;
}

.mobile-picker-empty {
    border: 1px dashed var(--app-border-strong);
    border-radius: 18px;
    padding: 1rem;
    color: var(--app-text-soft);
    text-align: center;
    background: rgba(255, 255, 255, 0.65);
}

@media (max-width: 991.98px) {
    .chart-wrap-lg {
        height: 360px;
    }

    .nav-user-name {
        max-width: 180px;
    }

    .nav-user-meta {
        max-width: 190px;
    }
}

@media (max-width: 575.98px) {
    .navbar {
        min-height: 64px;
    }

    .app-shell {
        padding-top: 1rem;
        padding-bottom: 1rem;
    }

    .app-page-title {
        font-size: 1.5rem;
    }

    .auth-card .card-body {
        padding: 1.25rem;
    }

    .kpi-value {
        font-size: 1.65rem;
    }

    .btn-lg,
    .form-control-lg,
    .form-select-lg {
        min-height: 50px;
    }

    .chart-wrap-lg {
        height: 320px;
    }

    .app-brand-subtitle,
    .nav-user-meta,
    .nav-user-separator {
        display: none;
    }

    .nav-user {
        gap: 0.55rem;
    }

    .nav-user-name {
        max-width: 120px;
    }

    .nav-user-avatar {
        width: 36px;
        height: 36px;
        font-size: 0.88rem;
    }

    .nav-user-badge {
        min-height: 22px;
        padding: 0.18rem 0.48rem;
        font-size: 0.66rem;
    }
}