/* ============================================================
   Clases · Identidad visual
   Tema tecnológico oscuro, limpio y responsive. Sin animaciones pesadas.
   ============================================================ */

:root {
    --bg: #0d1220;
    --bg-soft: #131a2e;
    --surface: #1a2338;
    --surface-2: #212c47;
    --border: #2c3a5e;
    --text: #e8edf7;
    --text-muted: #93a1c0;
    --primary: #6c5ce7;
    --primary-2: #4f8cff;
    --success: #2ecc71;
    --danger: #ff5f6d;
    --warning: #f5a623;
    --radius: 12px;
    --shadow: 0 8px 24px rgba(0, 0, 0, .35);
    --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { -webkit-text-size-adjust: 100%; }

body {
    font-family: var(--font);
    background: radial-gradient(1200px 600px at 80% -10%, #1b2444 0%, var(--bg) 55%);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a { color: var(--primary-2); text-decoration: none; }
a:hover { text-decoration: underline; }

h1 { font-size: 1.7rem; }
h2 { font-size: 1.25rem; }
h3 { font-size: 1.05rem; }
h1, h2, h3 { line-height: 1.3; margin-bottom: .5rem; }

.muted { color: var(--text-muted); font-size: .92rem; }
.hint { color: var(--text-muted); font-size: .85rem; margin: .5rem 0; }
.prose { white-space: normal; }
.prose p { margin-bottom: .6rem; }

/* ---------- Barra superior ---------- */
.topbar {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(13, 18, 32, .92);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border);
}

.topbar-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: .7rem 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.brand { display: flex; align-items: center; gap: .55rem; color: var(--text); font-weight: 700; font-size: 1.15rem; }
.brand:hover { text-decoration: none; }

.brand-mark {
    display: inline-flex; align-items: center; justify-content: center;
    width: 34px; height: 34px; border-radius: 10px;
    background: linear-gradient(135deg, var(--primary), var(--primary-2));
    color: #fff; font-weight: 800; font-size: 1.05rem;
    box-shadow: 0 4px 14px rgba(108, 92, 231, .45);
}

.brand-mark-lg { width: 56px; height: 56px; font-size: 1.7rem; border-radius: 16px; }

.main-nav { display: flex; align-items: center; gap: .35rem; margin-left: auto; flex-wrap: wrap; }

.nav-link {
    color: var(--text-muted);
    padding: .45rem .75rem;
    border-radius: 8px;
    font-size: .92rem;
}
.nav-link:hover { color: var(--text); text-decoration: none; background: var(--surface-2); }
.nav-link.active { color: #fff; background: linear-gradient(135deg, var(--primary), var(--primary-2)); }

.nav-logout { margin: 0; }
.nav-logout-btn { background: none; border: none; cursor: pointer; font-family: inherit; }

.nav-toggle {
    display: none;
    margin-left: auto;
    background: var(--surface-2);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: .3rem .7rem;
    font-size: 1.1rem;
    cursor: pointer;
}

/* ---------- Contenido ---------- */
.app-main { flex: 1; width: 100%; max-width: 1100px; margin: 0 auto; padding: 1.4rem 1rem 3rem; }

.page { }
.page-narrow { max-width: 820px; margin: 0 auto; }

.page-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 1rem; margin-bottom: 1.3rem; flex-wrap: wrap; }

.breadcrumb { font-size: .85rem; color: var(--text-muted); margin-bottom: .3rem; }
.breadcrumb a { color: var(--primary-2); }

.section-title { margin: 1.6rem 0 .8rem; border-bottom: 1px solid var(--border); padding-bottom: .4rem; }

/* ---------- Tarjetas ---------- */
.grid { display: grid; gap: 1rem; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.1rem 1.2rem;
    box-shadow: var(--shadow);
}

.card-accent { border-left: 4px solid var(--primary); }
.card-success { border-left: 4px solid var(--success); }
.card-error { border-left: 4px solid var(--danger); }

.card-title { font-weight: 700; font-size: 1.1rem; }

.card-actions { margin-top: 1rem; display: flex; gap: .6rem; flex-wrap: wrap; }
.course-card-head { display: flex; gap: .8rem; align-items: center; margin-bottom: .6rem; }
.course-icon { font-size: 1.9rem; }
.course-meta { display: flex; gap: .8rem; align-items: center; flex-wrap: wrap; margin: .6rem 0; }

/* ---------- Estado vacío ---------- */
.empty-state {
    text-align: center;
    padding: 2.6rem 1.2rem;
    background: var(--surface);
    border: 1px dashed var(--border);
    border-radius: var(--radius);
    margin: 1rem 0;
}
.empty-icon { font-size: 2.6rem; margin-bottom: .5rem; }
.empty-state .btn { margin-top: .9rem; }

/* ---------- Botones ---------- */
.btn {
    display: inline-block;
    padding: .55rem 1.1rem;
    border-radius: 9px;
    border: 1px solid var(--border);
    background: var(--surface-2);
    color: var(--text);
    font-size: .92rem;
    cursor: pointer;
    transition: filter .15s ease;
}
.btn:hover { filter: brightness(1.15); text-decoration: none; }

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-2));
    border: none;
    color: #fff;
    font-weight: 600;
    box-shadow: 0 6px 18px rgba(108, 92, 231, .4);
}

.btn-success { background: var(--success); border: none; color: #08301b; font-weight: 600; }
.btn-ghost { background: transparent; }
.btn-block { width: 100%; text-align: center; }

/* ---------- Formularios ---------- */
.field { display: block; margin-bottom: .9rem; }
.field span { display: block; font-size: .85rem; color: var(--text-muted); margin-bottom: .3rem; }

input[type="text"], input[type="email"], input[type="password"], textarea {
    width: 100%;
    padding: .6rem .75rem;
    border-radius: 9px;
    border: 1px solid var(--border);
    background: var(--bg-soft);
    color: var(--text);
    font-family: inherit;
    font-size: .95rem;
}
input:focus, textarea:focus { outline: 2px solid var(--primary); border-color: transparent; }
textarea { resize: vertical; }

/* ---------- Alertas ---------- */
.alert {
    padding: .75rem 1rem;
    border-radius: 9px;
    margin-bottom: 1rem;
    font-size: .92rem;
}
.alert-success { background: rgba(46, 204, 113, .12); border: 1px solid rgba(46, 204, 113, .4); color: #7ce0a8; }
.alert-error { background: rgba(255, 95, 109, .12); border: 1px solid rgba(255, 95, 109, .4); color: #ff9aa4; }

/* ---------- Preguntas ---------- */
.question-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.1rem 1.2rem;
    margin-bottom: 1rem;
}

.question-head { display: flex; align-items: center; flex-wrap: wrap; gap: .5rem; margin-bottom: .5rem; }
.question-text { font-weight: 600; margin-bottom: .8rem; }
.technical-text { white-space: normal; overflow-wrap: anywhere; }
.technical-text code {
    padding: .08rem .35rem;
    border: 1px solid var(--border);
    border-radius: 5px;
    background: var(--bg-soft);
    color: #b9d4ff;
    font-family: Consolas, "Courier New", monospace;
    font-size: .92em;
}

/* Preguntas en modo lección (envío conjunto) */
.lesson-question {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.1rem 1.2rem;
    margin-bottom: 1rem;
}
.lesson-question .question-number {
    font-weight: 700;
    font-size: .85rem;
    text-transform: uppercase;
    letter-spacing: .03em;
    color: var(--primary);
}
.lesson-evaluation .lesson-question textarea { width: 100%; }

.answer-list { display: flex; flex-direction: column; gap: .45rem; margin-bottom: .8rem; }
.answer-inline { flex-direction: row; flex-wrap: wrap; }

.answer-option {
    display: flex; align-items: center; gap: .55rem;
    padding: .55rem .8rem;
    border: 1px solid var(--border);
    border-radius: 9px;
    cursor: pointer;
    font-size: .93rem;
    background: var(--bg-soft);
}
.answer-option:hover { border-color: var(--primary); }
.answer-option input { accent-color: var(--primary); }

.feedback-options { margin-top: .5rem; }

.answer-show {
    background: var(--bg-soft);
    border: 1px solid var(--border);
    border-radius: 9px;
    padding: .7rem .9rem;
    margin-bottom: .9rem;
}

.result-stats {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: .7rem;
    margin-top: .8rem;
}
.result-stats div { background: var(--bg-soft); border-radius: 9px; padding: .7rem; }
.result-stats strong { display: block; font-size: 1.15rem; }
.result-stats span { color: var(--text-muted); font-size: .82rem; }
.result-correct { color: #7ce0a8; }
.result-incorrect { color: #ff9aa4; }
.result-concepts { margin-top: 1rem; }
.feedback-status { margin-left: auto; font-weight: 700; }
.feedback-status.is-correct { color: #7ce0a8; }
.feedback-status.is-incorrect { color: #ff9aa4; }
.explanation-box {
    margin: .9rem 0;
    padding: .85rem 1rem;
    border: 1px solid rgba(79, 140, 255, .35);
    border-radius: 9px;
    background: rgba(79, 140, 255, .08);
}
.concept-feedback { display: flex; align-items: center; gap: .5rem; flex-wrap: wrap; }
.diagnostic-callout { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-top: 1rem; }
.diagnostic-callout h2, .diagnostic-intro h1 { margin-top: .6rem; }
.diagnostic-submit { position: sticky; bottom: 1rem; z-index: 2; box-shadow: var(--shadow); }
.diagnostic-level { margin-top: 1rem; font-size: 1.1rem; }
.diagnostic-area-row { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: .35rem 1rem; margin-bottom: 1rem; }
.diagnostic-area-row .progress-bar, .diagnostic-area-row .progress-label { grid-column: 1 / -1; }
.xp-award { color: #ffd28a; font-size: 1.05rem; font-weight: 800; }
.xp-chip { color: #ffd28a; font-size: .82rem; font-weight: 800; }
.gamification-summary { margin-bottom: 1rem; }
.gamification-head { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-bottom: .8rem; }
.gamification-stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: .7rem; margin-top: 1rem; }
.gamification-stats div { background: var(--bg-soft); border-radius: 9px; padding: .7rem; }
.gamification-stats strong, .gamification-stats span { display: block; }
.gamification-stats span { color: var(--text-muted); font-size: .82rem; }
.daily-goal-complete { color: #7ce0a8; font-size: .9rem; font-weight: 700; margin: .65rem 0 0; }

@media (max-width: 640px) {
    .diagnostic-callout { align-items: stretch; flex-direction: column; }
    .gamification-head { align-items: stretch; flex-direction: column; }
    .gamification-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* ---------- Badges y chips ---------- */
.badge {
    display: inline-block;
    padding: .18rem .6rem;
    border-radius: 999px;
    font-size: .76rem;
    font-weight: 600;
    text-transform: capitalize;
    background: var(--surface-2);
    color: var(--text-muted);
    border: 1px solid var(--border);
}
.badge-success, .badge-completada, .badge-dominado { background: rgba(46, 204, 113, .15); color: #7ce0a8; border-color: rgba(46, 204, 113, .4); }
.badge-danger, .badge-debil { background: rgba(255, 95, 109, .15); color: #ff9aa4; border-color: rgba(255, 95, 109, .4); }
.badge-warning, .badge-en-repaso, .badge-en_progreso { background: rgba(245, 166, 35, .15); color: #ffd28a; border-color: rgba(245, 166, 35, .4); }
.badge-primary, .badge-disponible { background: rgba(108, 92, 231, .2); color: #b8b1ff; border-color: rgba(108, 92, 231, .5); }
.badge-muted, .badge-bloqueado, .badge-nuevo { background: var(--surface-2); color: var(--text-muted); }
.badge-facil, .badge-facil { background: rgba(46, 204, 113, .15); color: #7ce0a8; }
.badge-normal, .badge-intermedio { background: rgba(79, 140, 255, .18); color: #9ec5ff; }
.badge-dificil, .badge-avanzado { background: rgba(255, 95, 109, .15); color: #ff9aa4; }
.badge-lesson, .badge-open, .badge-multiple, .badge-true_false { background: var(--surface-2); color: var(--text); }
.badge-review { background: rgba(79, 140, 255, .18); color: #9ec5ff; }

.chip-list { list-style: none; display: flex; flex-wrap: wrap; gap: .45rem; }
.chip {
    display: inline-block;
    padding: .28rem .7rem;
    border-radius: 999px;
    font-size: .82rem;
    background: var(--surface-2);
    border: 1px solid var(--border);
    color: var(--text);
}
.chip-danger { background: rgba(255, 95, 109, .14); border-color: rgba(255, 95, 109, .45); color: #ff9aa4; }
.chip-success { background: rgba(46, 204, 113, .14); border-color: rgba(46, 204, 113, .45); color: #7ce0a8; }
.concept-chips { display: flex; flex-wrap: wrap; gap: .45rem; }

/* ---------- Barras de progreso ---------- */
.progress-bar {
    height: 9px;
    background: var(--bg-soft);
    border-radius: 999px;
    overflow: hidden;
    margin: .45rem 0 .3rem;
}
.progress-fill {
    height: 100%;
    border-radius: 999px;
    background: linear-gradient(90deg, var(--primary), var(--primary-2));
    transition: width .3s ease;
}
.progress-label { font-size: .82rem; color: var(--text-muted); }

.big-number { font-size: 2rem; font-weight: 800; color: var(--primary-2); }

/* ---------- Listas ---------- */
.stats-list { list-style: none; }
.stats-list li { padding: .3rem 0; border-bottom: 1px solid var(--border); font-size: .92rem; }
.stats-list li:last-child { border-bottom: none; }

.module-list { display: flex; flex-direction: column; gap: 1rem; }
.module-card-head { display: flex; gap: .9rem; align-items: flex-start; margin-bottom: .4rem; }
.module-number {
    display: inline-flex; align-items: center; justify-content: center;
    min-width: 34px; height: 34px;
    border-radius: 10px;
    background: linear-gradient(135deg, var(--primary), var(--primary-2));
    color: #fff; font-weight: 700;
}

.lesson-list { display: flex; flex-direction: column; margin-top: .5rem; }
.lesson-row {
    display: flex; align-items: center; gap: .7rem;
    padding: .55rem .6rem;
    border-radius: 9px;
    color: var(--text);
}
.lesson-row:hover { background: var(--surface-2); text-decoration: none; }
.lesson-status { color: var(--text-muted); font-size: .7rem; }
.lesson-status.completada { color: var(--success); }
.lesson-status.en_progreso { color: var(--warning); }
.lesson-title { flex: 1; }

.lesson-nav { display: flex; justify-content: space-between; margin-bottom: 1rem; }
.lesson-sections { display: flex; flex-direction: column; gap: .9rem; }
.lesson-section h2 { font-size: 1.1rem; color: var(--primary-2); }

.review-card { margin-bottom: 1.2rem; }
.review-head { display: flex; justify-content: space-between; gap: 1rem; align-items: flex-start; flex-wrap: wrap; margin-bottom: .8rem; }
.review-meta { display: flex; flex-direction: column; align-items: flex-end; gap: .3rem; }

/* ---------- Tablas ---------- */
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; font-size: .9rem; }
th, td { text-align: left; padding: .55rem .6rem; border-bottom: 1px solid var(--border); white-space: nowrap; }
.cell-question {
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    white-space: normal;
    word-break: break-word;
    max-width: 340px;
    min-width: 160px;
}
th { color: var(--text-muted); font-weight: 600; font-size: .82rem; text-transform: uppercase; letter-spacing: .04em; }

/* ---------- Login ---------- */
.auth-body { background: radial-gradient(900px 500px at 50% -10%, #232f5c 0%, var(--bg) 60%); justify-content: center; }
.auth-main { flex: 1; display: flex; align-items: center; justify-content: center; padding: 2rem 1rem; }

.auth-card {
    width: 100%;
    max-width: 400px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem 1.8rem;
    box-shadow: var(--shadow);
}

.auth-brand { text-align: center; margin-bottom: 1.4rem; }
.auth-brand h1 { margin: .6rem 0 .2rem; }
.auth-brand p { color: var(--text-muted); font-size: .92rem; }
.auth-form .btn { margin-top: .4rem; }
.auth-help { margin-top: 1.2rem; text-align: center; font-size: .82rem; color: var(--text-muted); }
.auth-help code { background: var(--bg-soft); padding: .1rem .35rem; border-radius: 5px; }

/* ---------- Footer ---------- */
.footer {
    text-align: center;
    padding: 1.2rem;
    color: var(--text-muted);
    font-size: .8rem;
    border-top: 1px solid var(--border);
    background: rgba(13, 18, 32, .6);
}

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
    .grid-3 { grid-template-columns: 1fr; }
    .grid-2 { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
    .result-stats { grid-template-columns: 1fr; }
    .nav-toggle { display: block; }
    .main-nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0; right: 0;
        flex-direction: column;
        align-items: stretch;
        background: var(--bg-soft);
        border-bottom: 1px solid var(--border);
        padding: .6rem;
        gap: .2rem;
    }
    body.nav-open .main-nav { display: flex; }
    body.nav-open .nav-toggle { background: var(--primary); }
    .nav-logout-btn { width: 100%; text-align: left; }
}