:root {
    --body-bg: #eef3fb;
    --body-color: #182235;
    --surface-bg: rgba(255, 255, 255, 0.92);
    --surface-border: rgba(148, 163, 184, 0.24);
    --surface-shadow: 0 18px 45px rgba(15, 23, 42, 0.08);
    --header-bg: rgba(248, 250, 252, 0.88);
    --muted-color: #5b6b84;
    --accent: #2563eb;
    --danger-soft: rgba(220, 38, 38, 0.08);
    --danger-border: rgba(248, 113, 113, 0.32);
    --table-header-bg: rgba(241, 245, 249, 0.95);
    --table-border-color: rgba(148, 163, 184, 0.22);
    --code-bg: #e2e8f0;
    --code-color: #1d4ed8;
}

body.theme-dark {
    --body-bg: #07101d;
    --body-color: #f8fafc;
    --surface-bg: rgba(17, 27, 45, 0.9);
    --surface-border: rgba(71, 85, 105, 0.35);
    --surface-shadow: 0 18px 45px rgba(2, 6, 23, 0.5);
    --header-bg: rgba(23, 37, 63, 0.86);
    --muted-color: #a9b8cf;
    --accent: #60a5fa;
    --danger-soft: rgba(248, 113, 113, 0.12);
    --danger-border: rgba(248, 113, 113, 0.28);
    --table-header-bg: rgba(27, 41, 67, 0.95);
    --table-border-color: rgba(71, 85, 105, 0.3);
    --code-bg: rgba(37, 99, 235, 0.14);
    --code-color: #bfdbfe;
}

body {
    min-height: 100vh;
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    color: var(--body-color);
    background:
        radial-gradient(circle at top left, rgba(37, 99, 235, 0.09), transparent 28%),
        radial-gradient(circle at top right, rgba(14, 165, 233, 0.08), transparent 24%),
        linear-gradient(180deg, rgba(226, 232, 240, 0.55), transparent 240px),
        var(--body-bg);
    transition: background-color 0.25s ease, color 0.25s ease;
}

body.theme-dark {
    background:
        radial-gradient(circle at top left, rgba(37, 99, 235, 0.18), transparent 28%),
        radial-gradient(circle at top right, rgba(14, 165, 233, 0.1), transparent 22%),
        linear-gradient(180deg, rgba(15, 23, 42, 0.7), transparent 260px),
        var(--body-bg);
}

.app-navbar {
    background: linear-gradient(90deg, #15356d 0%, #1d4ed8 55%, #1d7cf2 100%);
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.16);
}

.navbar-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    font-weight: 700;
}

.navbar .nav-link,
.navbar .btn {
    font-size: 0.92rem;
}

.logout-link {
    white-space: nowrap;
}

.app-shell {
    min-height: calc(100vh - 68px);
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 1rem;
    flex-wrap: wrap;
}

.page-header h1 {
    font-size: clamp(2rem, 2.7vw, 2.7rem);
    font-weight: 700;
    margin-bottom: 0.35rem;
}

.eyebrow {
    display: inline-flex;
    margin-bottom: 0.55rem;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent);
}

.surface-card,
.card {
    background: var(--surface-bg);
    border: 1px solid var(--surface-border);
    border-radius: 20px;
    box-shadow: var(--surface-shadow);
    backdrop-filter: blur(16px);
}

.surface-card-header,
.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.15rem;
    background: var(--header-bg);
    border-bottom: 1px solid var(--surface-border);
    border-radius: 20px 20px 0 0 !important;
    color: var(--body-color);
}

.surface-card-header h5,
.card-header h5 {
    margin: 0;
    font-weight: 700;
}

.surface-card-body,
.card-body {
    padding: 1.15rem;
}

.text-muted,
.form-text,
small {
    color: var(--muted-color) !important;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1rem;
}

.metric-card {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    min-height: 142px;
    padding: 1.2rem 1.25rem;
    border-radius: 18px;
    color: #fff;
    box-shadow: 0 18px 35px rgba(15, 23, 42, 0.18);
}

.metric-card p {
    margin-bottom: 0.55rem;
    color: rgba(255, 255, 255, 0.8);
}

.metric-card h2 {
    margin: 0;
    font-size: clamp(2rem, 2.8vw, 2.55rem);
    font-weight: 700;
}

.metric-card i {
    font-size: 2rem;
    opacity: 0.65;
}

.metric-primary { background: linear-gradient(135deg, #2457d6, #1d4ed8); }
.metric-warning { background: linear-gradient(135deg, #b45309, #c26511); }
.metric-success { background: linear-gradient(135deg, #15803d, #16a34a); }
.metric-info { background: linear-gradient(135deg, #0f8fd0, #1da6f0); }

.content-grid {
    display: grid;
    gap: 1rem;
}

.content-grid-dashboard {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.config-layout {
    display: grid;
    grid-template-columns: minmax(290px, 360px) minmax(0, 1fr);
    gap: 1rem;
    align-items: start;
}

.config-main {
    min-width: 0;
}

.chat-status-box {
    padding: 0.95rem 1rem;
    border-radius: 14px;
    border: 1px dashed var(--surface-border);
    background: rgba(148, 163, 184, 0.06);
}

.today-columns {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1rem;
}

.today-column-header {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin-bottom: 0.75rem;
}

.today-column .list-group {
    min-height: 260px;
    max-height: 320px;
    overflow-y: auto;
    background: transparent;
}

.list-group-item {
    background: transparent;
    border-color: var(--surface-border);
    color: var(--body-color);
}

.table {
    margin-bottom: 0;
    color: inherit;
    --bs-table-bg: transparent;
    --bs-table-striped-bg: rgba(148, 163, 184, 0.08);
    --bs-table-hover-bg: rgba(59, 130, 246, 0.08);
    --bs-table-border-color: var(--table-border-color);
}

.table thead th,
.table-light th {
    background: var(--table-header-bg) !important;
    color: var(--body-color);
    font-weight: 700;
    border-color: var(--table-border-color);
}

.table tbody td,
.table tbody th {
    background: transparent !important;
    color: var(--body-color);
    border-color: var(--table-border-color);
}

.table tbody tr.table-danger {
    background: var(--danger-soft) !important;
    box-shadow: inset 4px 0 0 #ff6b6b;
}

.table tbody tr.table-danger td,
.table tbody tr.table-danger th {
    color: var(--body-color);
}

.badge.bg-info-subtle {
    background: rgba(14, 165, 233, 0.16) !important;
}

code {
    background: var(--code-bg);
    color: var(--code-color);
    padding: 0.12rem 0.45rem;
    border-radius: 0.45rem;
}

.empty-state {
    min-height: 240px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: var(--muted-color);
    padding: 2rem 1rem;
}

.empty-state.compact {
    min-height: 180px;
}

.empty-state i {
    font-size: 2.4rem;
    margin-bottom: 0.8rem;
}

.quickstart-list li + li {
    margin-top: 0.55rem;
}

.system-log-wrapper {
    max-height: 420px;
    overflow-y: auto;
}

.theme-dark .attempt-card {
    background: rgba(14, 24, 42, 0.96);
    border-color: rgba(59, 130, 246, 0.18);
}

.theme-dark .attempt-card .text-muted,
.theme-dark .attempt-card small {
    color: #cbd5e1 !important;
}

.theme-dark .attempt-card .question-row {
    background: rgba(10, 18, 32, 0.9);
    border-color: rgba(71, 85, 105, 0.4);
}

.theme-dark .attempt-card .badge.text-bg-light {
    background-color: #e5edf9 !important;
    color: #0f172a !important;
}

.theme-dark .attempt-card .answer-chip-danger {
    background: rgba(185, 28, 28, 0.28);
    color: #ffe2e2;
    border: 1px solid rgba(248, 113, 113, 0.34);
}

.theme-dark .attempt-card .answer-chip-success {
    background: rgba(21, 128, 61, 0.28);
    color: #dcfce7;
    border: 1px solid rgba(74, 222, 128, 0.25);
}

.form-control,
.form-select {
    border-radius: 0.9rem;
    border-color: rgba(148, 163, 184, 0.34);
    padding: 0.72rem 0.9rem;
    background: rgba(255, 255, 255, 0.88);
    color: var(--body-color);
}

.theme-dark .form-control,
.theme-dark .form-select {
    background: rgba(15, 23, 42, 0.72);
    border-color: rgba(71, 85, 105, 0.46);
    color: var(--body-color);
}

.form-control:focus,
.form-select:focus {
    border-color: rgba(37, 99, 235, 0.55);
    box-shadow: 0 0 0 0.25rem rgba(37, 99, 235, 0.16);
}

.btn {
    border-radius: 0.85rem;
}

.btn-sm {
    border-radius: 0.75rem;
}

.login-page {
    background:
        radial-gradient(circle at 20% 15%, rgba(37, 99, 235, 0.18), transparent 25%),
        radial-gradient(circle at 80% 10%, rgba(14, 165, 233, 0.18), transparent 20%),
        linear-gradient(180deg, #09152d 0%, #10244b 42%, #19376b 100%);
    background-attachment: fixed;
}

.login-shell {
    min-height: 100vh;
}

.login-hero {
    color: #fff;
    max-width: 620px;
}

.login-hero h1 {
    font-size: clamp(2.4rem, 4vw, 3.9rem);
    font-weight: 700;
    line-height: 1.02;
    margin-bottom: 1rem;
}

.login-hero .lead {
    font-size: 1.07rem;
    color: rgba(255, 255, 255, 0.82);
    max-width: 48rem;
}

.login-feature-list {
    display: grid;
    gap: 0.85rem;
    margin-top: 1.4rem;
}

.login-feature {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.9rem 1rem;
    border-radius: 1rem;
    background: rgba(15, 23, 42, 0.22);
    border: 1px solid rgba(255, 255, 255, 0.14);
}

.login-icon {
    width: 72px;
    height: 72px;
    display: grid;
    place-items: center;
    border-radius: 50%;
    background: rgba(37, 99, 235, 0.12);
    color: #2563eb;
    font-size: 2rem;
}

.login-card {
    position: relative;
    background: rgba(255, 255, 255, 0.94);
    overflow: visible;
}

.login-card::before {
    content: "";
    position: absolute;
    inset: -24px;
    border-radius: 32px;
    background:
        radial-gradient(circle, rgba(96, 165, 250, 0.22) 0%, rgba(96, 165, 250, 0.08) 45%, transparent 72%);
    filter: blur(14px);
    z-index: -1;
    pointer-events: none;
}

.theme-dark .surface-card,
.theme-dark .card,
.theme-dark .list-group-item {
    color: var(--body-color);
}

@media (max-width: 1199px) {
    .stats-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .config-layout {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 991px) {
    .content-grid-dashboard,
    .today-columns {
        grid-template-columns: 1fr;
    }

    .page-header {
        align-items: flex-start;
    }
}

@media (max-width: 767px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }

    .metric-card {
        min-height: 120px;
    }

    .surface-card-header,
    .card-header,
    .surface-card-body,
    .card-body {
        padding: 0.95rem;
    }
}