:root {
    --qm-primary: #174b8a;
    --qm-primary-dark: #0f3564;
    --qm-accent: #0c7c74;
    --qm-bg: #f4f7fb;
    --qm-text: #172033;
    --qm-muted: #5e6878;
    --qm-border: #dce3ec;
    --qm-success: #176b45;
    --qm-success-bg: #eaf7f0;
    --qm-danger: #a52832;
    --qm-danger-bg: #fcecef;
    --qm-warning: #8a5a00;
    --qm-shadow: 0 16px 40px rgba(26, 48, 82, .1);
}

html {
    min-height: 100%;
    scroll-behavior: smooth;
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    color: var(--qm-text);
    background: var(--qm-bg);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

main { flex: 1; }

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

.skip-link {
    position: fixed;
    left: 1rem;
    top: -5rem;
    z-index: 9999;
    background: #fff;
    color: #000;
    padding: .75rem 1rem;
    border-radius: .5rem;
    box-shadow: var(--qm-shadow);
}
.skip-link:focus { top: 1rem; }

.site-header { position: relative; z-index: 1030; }
.site-header .navbar { background: linear-gradient(110deg, var(--qm-primary-dark), var(--qm-primary)); }
.navbar-brand { display: flex; align-items: center; gap: .65rem; }
.brand-mark {
    display: inline-grid;
    place-items: center;
    width: 2.2rem;
    height: 2.2rem;
    border-radius: .65rem;
    background: rgba(255,255,255,.15);
    font-size: .82rem;
    letter-spacing: .04em;
}

.hero-section {
    background:
        radial-gradient(circle at 82% 18%, rgba(12,124,116,.14), transparent 30%),
        linear-gradient(180deg, #fff, var(--qm-bg));
}

.eyebrow {
    display: inline-block;
    color: var(--qm-accent);
    font-size: .78rem;
    font-weight: 800;
    letter-spacing: .11em;
    text-transform: uppercase;
}

.hero-panel {
    display: grid;
    gap: 1rem;
    padding: 1.5rem;
    border-radius: 1.4rem;
    background: #fff;
    box-shadow: var(--qm-shadow);
    border: 1px solid rgba(23,75,138,.08);
}
.hero-stat {
    display: flex;
    align-items: baseline;
    gap: 1rem;
    padding: 1rem;
    border-radius: 1rem;
    background: #f7f9fc;
}
.hero-stat strong { font-size: 2rem; color: var(--qm-primary); }
.hero-stat span { color: var(--qm-muted); }

.btn-primary {
    --bs-btn-bg: var(--qm-primary);
    --bs-btn-border-color: var(--qm-primary);
    --bs-btn-hover-bg: var(--qm-primary-dark);
    --bs-btn-hover-border-color: var(--qm-primary-dark);
    --bs-btn-active-bg: var(--qm-primary-dark);
    --bs-btn-active-border-color: var(--qm-primary-dark);
}
.btn-outline-primary {
    --bs-btn-color: var(--qm-primary);
    --bs-btn-border-color: var(--qm-primary);
    --bs-btn-hover-bg: var(--qm-primary);
    --bs-btn-hover-border-color: var(--qm-primary);
}

.mode-card,
.app-card,
.quiz-shell,
.question-panel {
    background: #fff;
    border: 1px solid var(--qm-border);
    border-radius: 1.2rem;
    box-shadow: var(--qm-shadow);
}

.mode-card {
    display: flex;
    flex-direction: column;
    padding: 1.75rem;
}
.mode-card p { color: var(--qm-muted); }
.mode-number {
    margin-bottom: 1rem;
    color: var(--qm-accent);
    font-weight: 800;
    letter-spacing: .1em;
}
.feature-list { padding-left: 1.25rem; margin-bottom: 1.5rem; }
.feature-list li + li { margin-top: .5rem; }
.modality-data { margin-top: 1rem; }
.modality-data dt, .modality-data dd { padding-top: .4rem; padding-bottom: .4rem; border-bottom: 1px solid #edf1f6; }
.availability { font-weight: 700; }
.available { color: var(--qm-success); }
.unavailable { color: var(--qm-danger); }

.privacy-strip { color: #fff; background: linear-gradient(110deg, var(--qm-primary-dark), var(--qm-primary)); }
.page-banner { background: #fff; border-bottom: 1px solid var(--qm-border); }
.section-heading { max-width: 48rem; }

.app-card { max-width: 860px; }
.quiz-shell { padding: 1.25rem; }
.quiz-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}
.score-box {
    display: flex;
    align-items: center;
    gap: .75rem;
    padding: .65rem 1rem;
    border-radius: .8rem;
    background: #eef4fb;
}
.score-box strong { color: var(--qm-primary); font-size: 1.35rem; }
.progress { height: .75rem; background: #e7edf5; }
.progress-bar { background: linear-gradient(90deg, var(--qm-primary), var(--qm-accent)); }

.question-card { padding: .5rem; }
.question-text {
    font-size: clamp(1.25rem, 2vw, 1.65rem);
    line-height: 1.45;
    outline: none;
}
.option-list { display: grid; gap: .85rem; }
.option-button {
    width: 100%;
    display: flex;
    align-items: flex-start;
    gap: .9rem;
    text-align: left;
    padding: 1rem;
    border: 2px solid var(--qm-border);
    border-radius: .9rem;
    background: #fff;
    color: var(--qm-text);
    transition: border-color .15s ease, box-shadow .15s ease, background .15s ease;
}
.option-button:hover:not(:disabled),
.option-button:focus-visible {
    border-color: var(--qm-primary);
    box-shadow: 0 0 0 .25rem rgba(23,75,138,.14);
    outline: none;
}
.option-button:disabled { opacity: 1; cursor: default; }
.option-marker {
    flex: 0 0 auto;
    display: inline-grid;
    place-items: center;
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    background: #edf2f8;
    color: var(--qm-primary);
    font-weight: 800;
}
.option-text { padding-top: .2rem; }
.option-selected { border-color: var(--qm-primary); }
.option-correct { border-color: var(--qm-success); background: var(--qm-success-bg); }
.option-incorrect { border-color: var(--qm-danger); background: var(--qm-danger-bg); }

.feedback-box { padding: 1.1rem; border-radius: .9rem; border-left: .35rem solid; }
.feedback-correct { background: var(--qm-success-bg); border-color: var(--qm-success); }
.feedback-incorrect { background: var(--qm-danger-bg); border-color: var(--qm-danger); }

.sidebar-ad { min-height: 600px; }
.ad-space {
    min-height: 110px;
    display: grid;
    place-items: center;
    overflow: hidden;
}
.ad-placeholder {
    border: 1px dashed #aeb9c8;
    border-radius: .85rem;
    background: #f8fafc;
    color: #667085;
    font-size: .82rem;
    text-transform: uppercase;
    letter-spacing: .08em;
}

.exam-sticky-bar {
    position: sticky;
    top: 0;
    z-index: 1020;
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: 1rem;
    padding: .85rem 1rem;
    border-radius: 0 0 1rem 1rem;
    background: #fff;
    box-shadow: 0 10px 25px rgba(26,48,82,.12);
    border: 1px solid var(--qm-border);
}
.exam-sticky-bar > :last-child { justify-self: end; }
.timer { display: block; font-size: 1.6rem; font-variant-numeric: tabular-nums; color: var(--qm-primary); }
.timer-warning { color: var(--qm-warning); }
.timer-danger { color: var(--qm-danger); }

.exam-option {
    margin: 0;
    padding: 0;
    border: 2px solid var(--qm-border);
    border-radius: .9rem;
    background: #fff;
}
.exam-option:has(input:checked) { border-color: var(--qm-primary); background: #f2f7fd; }
.exam-option:focus-within { box-shadow: 0 0 0 .25rem rgba(23,75,138,.14); }
.exam-option .form-check-input { position: absolute; opacity: 0; pointer-events: none; }
.exam-option .form-check-label {
    width: 100%;
    display: flex;
    align-items: flex-start;
    gap: .9rem;
    padding: 1rem;
    cursor: pointer;
}
.exam-option input:disabled + .form-check-label { cursor: default; }
.exam-controls { display: flex; justify-content: space-between; gap: 1rem; }

.question-panel { padding: 1.25rem; top: 6.5rem; }
.question-legend { display: flex; flex-wrap: wrap; gap: 1rem; color: var(--qm-muted); font-size: .9rem; }
.question-grid { display: grid; grid-template-columns: repeat(4, minmax(0,1fr)); gap: .5rem; max-height: 55vh; overflow: auto; padding-right: .25rem; }
.question-nav-button {
    min-height: 2.8rem;
    border: 1px solid var(--qm-border);
    border-radius: .65rem;
    background: #fff;
    font-size: .8rem;
    font-weight: 700;
}
.question-nav-button.is-answered { background: var(--qm-success-bg); border-color: var(--qm-success); color: var(--qm-success); }
.question-nav-button.is-current { outline: 3px solid rgba(23,75,138,.25); border-color: var(--qm-primary); }
.question-nav-button:focus-visible { outline: 3px solid rgba(23,75,138,.35); }

.result-icon {
    display: inline-grid;
    place-items: center;
    width: 4rem;
    height: 4rem;
    border-radius: 50%;
    color: #fff;
    background: var(--qm-success);
    font-size: 2rem;
}
.result-grid { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 1rem; }
.result-metric { padding: 1.1rem; border: 1px solid var(--qm-border); border-radius: .9rem; background: #f9fbfd; }
.result-metric strong { display: block; font-size: 1.6rem; color: var(--qm-primary); }
.result-metric span { color: var(--qm-muted); }
.result-metadata dt { color: var(--qm-muted); }

.review-accordion .accordion-item { border-color: var(--qm-border); }
.review-accordion .accordion-button { gap: .8rem; font-weight: 700; }
.review-status { min-width: 7.5rem; display: inline-block; font-size: .76rem; text-align: center; padding: .35rem .55rem; border-radius: 999px; }
.status-correcta { color: var(--qm-success); background: var(--qm-success-bg); }
.status-incorrecta { color: var(--qm-danger); background: var(--qm-danger-bg); }
.status-no_respondida { color: #555; background: #eceff3; }
.review-options { display: grid; gap: .65rem; margin-bottom: 1rem; }
.review-option { display: flex; justify-content: space-between; gap: 1rem; padding: .8rem; border: 1px solid var(--qm-border); border-radius: .7rem; }
.review-option-correct { border-color: var(--qm-success); background: var(--qm-success-bg); }
.review-option-incorrect { border-color: var(--qm-danger); background: var(--qm-danger-bg); }
.review-option-tags { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: .35rem; }

.legal-page { max-width: 900px; }
.legal-page h2 { margin-top: 2rem; font-size: 1.35rem; }
.site-footer { color: #dce7f5; background: #102d50; }
.site-footer a { color: #fff; }

@media (max-width: 991.98px) {
    .exam-sticky-bar { grid-template-columns: 1fr 1fr; }
    .exam-sticky-bar > :nth-child(2) { text-align: right !important; }
    .exam-sticky-bar > :last-child { grid-column: 1 / -1; width: 100%; }
    .result-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
}

@media (max-width: 575.98px) {
    .hero-section .display-5 { font-size: 2.15rem; }
    .mode-card, .quiz-shell, .question-panel { border-radius: .9rem; }
    .quiz-shell { padding: .9rem; }
    .quiz-toolbar { align-items: flex-start; }
    .score-box { padding: .5rem .75rem; }
    .exam-sticky-bar { margin-left: -.75rem; margin-right: -.75rem; border-radius: 0; }
    .timer { font-size: 1.3rem; }
    .exam-controls { flex-direction: column; }
    .exam-controls .btn { width: 100%; }
    .question-grid { grid-template-columns: repeat(3, minmax(0,1fr)); }
    .result-grid { grid-template-columns: 1fr; }
    .review-option { flex-direction: column; }
    .review-option-tags { justify-content: flex-start; }
    .review-status { min-width: auto; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}