/*
 * Public frontend styles — layered on top of stock Bootstrap 5.3.
 * Admin uses assets/css/style.css; this file is loaded only by the public templates.
 */

/* ── Sleek design refinements (safe Bootstrap variable overrides) ── */
[data-bs-theme="light"] {
    --bs-border-color: #e6e8ec;
    --bs-tertiary-bg: #f7f8fa;
    --bs-body-bg-rgb: 255, 255, 255;
}
:root {
    --bs-border-radius: .625rem;
    --bs-border-radius-sm: .45rem;
    --bs-border-radius-lg: .85rem;
}
body { -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }

/* Softer, lighter elevation than Bootstrap's default .shadow-sm */
.shadow-sm { box-shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 1px 3px rgba(15, 23, 42, .06) !important; }

/* Card links: gentle lift on hover */
.card { transition: box-shadow .15s ease, transform .15s ease, border-color .15s ease; }
a.card:hover {
    box-shadow: 0 6px 16px rgba(15, 23, 42, .08) !important;
    transform: translateY(-1px);
    border-color: var(--bs-primary);
}

/* Slimmer, quieter top navbar */
.navbar { padding-top: .5rem; padding-bottom: .5rem; }
.navbar-brand { letter-spacing: -.01em; }

/* ── Sidebar ── */
.app-sidebar .nav-link {
    color: var(--bs-body-color);
    border-radius: .375rem;
    padding: .5rem .75rem;
}
.app-sidebar .nav-link:hover {
    background-color: var(--bs-secondary-bg);
}
.app-sidebar .nav-link.active {
    color: #fff;
    background-color: var(--bs-primary);
}
.app-sidebar .sidebar-heading {
    font-size: .75rem;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--bs-secondary-color);
}

@media (min-width: 768px) {
    .app-sidebar {
        position: sticky;
        top: 0;
        height: 100vh;
        border-right: 1px solid var(--bs-border-color);
        overflow-y: auto;
    }
}

/* ── Math rendering ── */
/* Inline math flows with the text — no box and no inner scrollbar. */
.math-render { max-width: 100%; }
span.math-render { display: inline; }
/* Only block/display math can be wide enough to need horizontal scroll. */
div.math-render { display: block; margin: .5rem 0; overflow-x: auto; }

/* ── Question card difficulty accent ── */
.question-card { border-left: 4px solid var(--bs-border-color); }
.question-card.easy   { border-left-color: var(--bs-success); }
.question-card.medium { border-left-color: var(--bs-warning); }
.question-card.hard   { border-left-color: var(--bs-danger); }

/* ── Answer options ── */
.option-item .option-label { font-weight: 700; min-width: 1.5rem; color: var(--bs-primary); }
.option-item.correct {
    border-color: var(--bs-success) !important;
    background-color: rgba(var(--bs-success-rgb), .1);
}

/* ── Pagination (renderPagination() emits flat .page-link markup) ── */
.pagination { flex-wrap: wrap; gap: .25rem; justify-content: center; }
.pagination .page-link { border-radius: var(--bs-border-radius); }
.pagination .page-link.active {
    background-color: var(--bs-primary);
    border-color: var(--bs-primary);
    color: #fff;
}
.page-ellipsis { display: inline-flex; align-items: center; padding: 0 .4rem; color: var(--bs-secondary-color); }

/* ── Ad container (Google AdSense) ── */
.ad-container { margin: 2rem 0 .5rem; text-align: center; }
.ad-container .ad-label {
    display: block;
    font-size: .7rem;
    font-weight: 500;
    letter-spacing: .04em;
    text-transform: uppercase;
    color: var(--bs-secondary-color);
    margin-bottom: .35rem;
}
.ad-container .adsbygoogle { display: block; }
.ad-container .ad-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 90px;
    border: 1px dashed var(--bs-border-color);
    border-radius: var(--bs-border-radius);
    background: var(--bs-secondary-bg);
    color: var(--bs-secondary-color);
    font-size: .8rem;
}

/* ── Dark-mode toggle icon ── */
#theme-toggle .icon-sun  { display: none; }
[data-bs-theme="dark"] #theme-toggle .icon-sun  { display: inline; }
[data-bs-theme="dark"] #theme-toggle .icon-moon { display: none; }