/* ══════════════════════════════════════════════
   ESTUDIO CENEVAL - Design System
   Plataforma educativa moderna - Azul Marino
   ══════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

:root {
    --primary: #1e3a5f;
    --primary-dark: #0d1f3c;
    --primary-light: #2c5282;
    --secondary: #0ea5e9;
    --accent: #1a4d7c;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --dark: #0f172a;
    --dark-2: #1e293b;
    --dark-3: #334155;
    --gray: #64748b;
    --gray-light: #94a3b8;
    --light: #f1f5f9;
    --light-2: #e2e8f0;
    --white: #ffffff;
    --gradient-1: linear-gradient(135deg, #1e3a5f 0%, #2c5282 50%, #3b82f6 100%);
    --gradient-2: linear-gradient(135deg, #0ea5e9 0%, #1e3a5f 100%);
    --gradient-3: linear-gradient(135deg, #10b981 0%, #0ea5e9 100%);
    --gradient-premium: linear-gradient(135deg, #f59e0b 0%, #ef4444 50%, #ec4899 100%);
    --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
    --shadow: 0 4px 20px rgba(0,0,0,.08);
    --shadow-lg: 0 10px 40px rgba(0,0,0,.12);
    --shadow-glow: 0 0 30px rgba(30,58,95,.15);
    --radius: 16px;
    --radius-sm: 10px;
    --radius-lg: 24px;
    --transition: all .3s cubic-bezier(.4,0,.2,1);
}

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

body {
    font-family: 'Inter', sans-serif;
    background: var(--light);
    color: var(--dark);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* ── Navbar ── */
.navbar-custom {
    background: var(--white);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--light-2);
    padding: .75rem 0;
    box-shadow: var(--shadow-sm);
}
.navbar-custom .navbar-brand {
    font-weight: 800;
    font-size: 1.3rem;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -.5px;
}
.navbar-custom .nav-link {
    color: var(--gray);
    font-weight: 500;
    padding: .5rem 1rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}
.navbar-custom .nav-link:hover, .navbar-custom .nav-link.active {
    color: var(--primary);
    background: rgba(30,58,95,.08);
}
/* ── Elementos del Navbar (Proporciones uniformes y alineación vertical) ── */
.nav-user-badge {
    background: #f1f5f9;
    color: var(--primary);
    border: 1px solid #cbd5e1;
    height: 36px;
    padding: 0 0.85rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.84rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    line-height: 1;
    white-space: nowrap;
    vertical-align: middle;
}
.nav-user-badge i {
    font-size: 0.95rem;
    color: var(--secondary);
}

.nav-btn-premium {
    background: linear-gradient(135deg, #f59e0b 0%, #ea580c 100%) !important;
    color: #ffffff !important;
    height: 36px;
    padding: 0 1rem !important;
    border-radius: 50px !important;
    font-weight: 700 !important;
    font-size: 0.84rem !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    text-decoration: none !important;
    box-shadow: 0 2px 8px rgba(245, 158, 11, 0.28);
    transition: var(--transition);
    border: none !important;
    line-height: 1;
    white-space: nowrap;
    vertical-align: middle;
}
.nav-btn-premium:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 14px rgba(245, 158, 11, 0.42);
    color: #ffffff !important;
}
.nav-btn-premium i {
    font-size: 0.9rem;
    color: #fef08a;
}

.nav-badge-premium-active {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: #ffffff;
    height: 36px;
    padding: 0 0.85rem;
    border-radius: 50px;
    font-weight: 700;
    font-size: 0.8rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    letter-spacing: 0.4px;
    text-transform: uppercase;
    box-shadow: 0 2px 6px rgba(16, 185, 129, 0.2);
    white-space: nowrap;
    vertical-align: middle;
}
.nav-badge-premium-active i {
    font-size: 0.85rem;
    color: #a7f3d0;
}

.nav-btn-logout {
    background: transparent !important;
    color: #dc2626 !important;
    border: 1.5px solid #fecaca !important;
    height: 36px;
    padding: 0 0.9rem !important;
    border-radius: 50px !important;
    font-weight: 600 !important;
    font-size: 0.84rem !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    transition: var(--transition);
    line-height: 1;
    white-space: nowrap;
    vertical-align: middle;
    cursor: pointer;
}
.nav-btn-logout:hover {
    background: #fef2f2 !important;
    border-color: #ef4444 !important;
    color: #b91c1c !important;
    transform: translateY(-1px);
}
.nav-btn-logout i {
    font-size: 0.9rem;
}

.badge-suscripcion {
    background: var(--gradient-premium);
    color: white;
    padding: .35rem .75rem;
    border-radius: 50px;
    font-weight: 700;
    font-size: .75rem;
    text-transform: uppercase;
    letter-spacing: .5px;
    display: inline-flex;
    align-items: center;
    gap: .3rem;
}

/* ── Landing Page ── */
.landing-hero {
    min-height: 100vh;
    background: var(--dark);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
}
.landing-hero::before {
    content: '';
    position: absolute;
    width: 800px; height: 800px;
    background: var(--gradient-1);
    border-radius: 50%;
    top: -300px; right: -200px;
    opacity: .12;
    filter: blur(100px);
}
.landing-hero::after {
    content: '';
    position: absolute;
    width: 500px; height: 500px;
    background: var(--gradient-3);
    border-radius: 50%;
    bottom: -150px; left: -100px;
    opacity: .08;
    filter: blur(80px);
}
.landing-content {
    position: relative;
    z-index: 1;
    color: white;
}
.landing-title {
    font-size: 3.2rem;
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -1px;
    margin-bottom: 1.5rem;
}
.landing-title span {
    background: var(--gradient-3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.landing-subtitle {
    font-size: 1.15rem;
    color: var(--gray-light);
    max-width: 520px;
    line-height: 1.7;
    margin-bottom: 2rem;
}
.landing-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 3rem;
}
.feature-card {
    background: rgba(255,255,255,.04);
    border: 1px solid rgba(255,255,255,.08);
    border-radius: var(--radius);
    padding: 1.75rem;
    transition: var(--transition);
}
.feature-card:hover {
    background: rgba(255,255,255,.07);
    border-color: rgba(255,255,255,.15);
    transform: translateY(-4px);
}
.feature-icon {
    width: 52px; height: 52px;
    border-radius: 14px;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.4rem; color: white;
    margin-bottom: 1rem;
}
.feature-card h4 { color: white; font-weight: 700; font-size: 1.1rem; margin-bottom: .5rem; }
.feature-card p { color: var(--gray-light); font-size: .9rem; line-height: 1.6; }
.feature-badge {
    display: inline-block;
    padding: .2rem .6rem;
    border-radius: 50px;
    font-size: .7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .5px;
    margin-bottom: .75rem;
}
.badge-free { background: rgba(16,185,129,.15); color: var(--success); }
.badge-premium { background: rgba(245,158,11,.15); color: var(--warning); }

/* ── Auth Pages ── */
.auth-wrapper {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--dark);
    position: relative;
    overflow: hidden;
}
.auth-wrapper::before {
    content: '';
    position: absolute;
    width: 600px; height: 600px;
    background: var(--gradient-1);
    border-radius: 50%;
    top: -200px; right: -200px;
    opacity: .15;
    filter: blur(80px);
}
.auth-wrapper::after {
    content: '';
    position: absolute;
    width: 400px; height: 400px;
    background: var(--gradient-3);
    border-radius: 50%;
    bottom: -100px; left: -100px;
    opacity: .1;
    filter: blur(60px);
}
.auth-card {
    background: rgba(255,255,255,.05);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255,255,255,.1);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    width: 100%;
    max-width: 440px;
    position: relative;
    z-index: 1;
}
.auth-card h2 {
    color: white;
    font-weight: 800;
    margin-bottom: .5rem;
}
.auth-card p { color: var(--gray-light); }
.auth-card .form-control {
    background: rgba(255,255,255,.07);
    border: 1px solid rgba(255,255,255,.12);
    color: white;
    border-radius: var(--radius-sm);
    padding: .75rem 1rem;
    font-size: .95rem;
    transition: var(--transition);
}
.auth-card .form-control:focus {
    background: rgba(255,255,255,.1);
    border-color: var(--secondary);
    box-shadow: 0 0 0 3px rgba(14,165,233,.25);
    color: white;
}
.auth-card .form-control::placeholder { color: var(--gray); }
.auth-card .form-label { color: var(--gray-light); font-weight: 500; font-size: .9rem; }
.auth-card a:not(.btn) { color: var(--secondary); text-decoration: none; }
.auth-card a:not(.btn):hover { color: white; text-decoration: underline; }
.auth-divider {
    display: flex; align-items: center; gap: 1rem;
    margin: 1.5rem 0; color: var(--gray);
}
.auth-divider::before, .auth-divider::after {
    content: ''; flex: 1; height: 1px; background: rgba(255,255,255,.1);
}

/* ── Buttons (Alta Legibilidad y Contraste) ── */
.btn-primary-custom, a.btn-primary-custom, button.btn-primary-custom {
    background: var(--gradient-1) !important;
    border: none !important;
    color: #ffffff !important;
    font-weight: 600;
    padding: .75rem 1.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    text-decoration: none !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}
.btn-primary-custom:hover, a.btn-primary-custom:hover, button.btn-primary-custom:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(30,58,95,.45);
    color: #ffffff !important;
}

.btn-secondary-custom, a.btn-secondary-custom, button.btn-secondary-custom {
    background: var(--white) !important;
    border: 1.5px solid var(--light-2) !important;
    color: var(--primary-dark) !important;
    font-weight: 600;
    padding: .75rem 1.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    text-decoration: none !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}
.btn-secondary-custom:hover, a.btn-secondary-custom:hover, button.btn-secondary-custom:hover {
    border-color: var(--primary) !important;
    color: var(--primary) !important;
    background: #f8fafc !important;
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0,0,0,.08);
}

.btn-success-custom, a.btn-success-custom, button.btn-success-custom {
    background: linear-gradient(135deg, #059669 0%, #0284c7 100%) !important;
    border: none !important;
    color: #ffffff !important;
    font-weight: 700;
    padding: .75rem 1.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    text-decoration: none !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-shadow: 0 1px 2px rgba(0,0,0,0.25);
}
.btn-success-custom:hover, a.btn-success-custom:hover, button.btn-success-custom:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(5,150,105,.45);
    color: #ffffff !important;
}

.btn-premium, a.btn-premium, button.btn-premium {
    background: var(--gradient-premium) !important;
    border: none !important;
    color: #ffffff !important;
    font-weight: 700;
    padding: .75rem 1.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    text-decoration: none !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-shadow: 0 1px 2px rgba(0,0,0,0.25);
}
.btn-premium:hover, a.btn-premium:hover, button.btn-premium:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(245,158,11,.45);
    color: #ffffff !important;
}
.btn-premium.btn-sm, a.btn-premium.btn-sm, button.btn-premium.btn-sm {
    padding: .35rem .95rem !important;
    font-size: .84rem !important;
    border-radius: 50px !important;
}

.btn-outline-navy, a.btn-outline-navy, button.btn-outline-navy {
    background: rgba(255,255,255,0.06) !important;
    border: 2px solid rgba(255,255,255,.45) !important;
    color: #ffffff !important;
    font-weight: 600;
    padding: .75rem 1.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    text-decoration: none !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}
.btn-outline-navy:hover, a.btn-outline-navy:hover, button.btn-outline-navy:hover {
    background: rgba(255,255,255,.18) !important;
    border-color: #ffffff !important;
    color: #ffffff !important;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0,0,0,.25);
}

.btn:disabled, button:disabled, .btn.disabled {
    opacity: 0.65 !important;
    cursor: not-allowed !important;
    box-shadow: none !important;
    transform: none !important;
}

/* ── Cards ── */
.card-custom {
    background: var(--white);
    border: 1px solid var(--light-2);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}
.card-custom:hover {
    box-shadow: var(--shadow);
    transform: translateY(-3px);
}

/* ── Stat Cards ── */
.stat-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 1.5rem;
    border: 1px solid var(--light-2);
    position: relative;
    overflow: hidden;
    transition: var(--transition);
}
.stat-card:hover { box-shadow: var(--shadow-glow); transform: translateY(-3px); }
.stat-card .stat-icon {
    width: 48px; height: 48px;
    border-radius: 12px;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.3rem; color: white;
    margin-bottom: 1rem;
}
.stat-card .stat-value { font-size: 1.8rem; font-weight: 800; line-height: 1; }
.stat-card .stat-label { color: var(--gray); font-size: .85rem; font-weight: 500; margin-top: .25rem; }

/* ── Exam Mode Cards ── */
.mode-card {
    background: var(--white);
    border: 2px solid var(--light-2);
    border-radius: var(--radius);
    padding: 1.75rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    text-decoration: none;
    color: var(--dark);
    display: block;
}
.mode-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-glow);
    transform: translateY(-4px);
    color: var(--dark);
}
.mode-card.locked {
    opacity: .7;
}
.mode-card.locked:hover {
    border-color: var(--warning);
    box-shadow: 0 0 20px rgba(245,158,11,.15);
}
.mode-icon {
    width: 60px; height: 60px;
    border-radius: 16px;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.6rem; color: white;
    margin-bottom: 1rem;
}
.mode-card h4 { font-weight: 700; font-size: 1.15rem; margin-bottom: .35rem; }
.mode-card .mode-desc { color: var(--gray); font-size: .9rem; line-height: 1.5; margin-bottom: 1rem; }
.mode-card .mode-meta {
    display: flex; gap: 1rem; font-size: .8rem; color: var(--gray-light);
}
.mode-lock-overlay {
    position: absolute; top: 1rem; right: 1rem;
    background: var(--gradient-premium);
    color: white; padding: .25rem .6rem;
    border-radius: 50px; font-size: .7rem; font-weight: 700;
    letter-spacing: .5px;
}

/* ── Topic Cards ── */
.topic-card {
    background: var(--white);
    border: 1px solid var(--light-2);
    border-radius: var(--radius);
    padding: 1.25rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.topic-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.topic-card .topic-indicator {
    width: 4px; height: 100%;
    position: absolute; left: 0; top: 0;
    border-radius: 4px 0 0 4px;
}
.topic-card .topic-name { font-weight: 600; font-size: 1rem; margin-bottom: .5rem; padding-left: .5rem; }
.topic-card .topic-stats { color: var(--gray); font-size: .8rem; padding-left: .5rem; }

/* ── Progress Bars ── */
.progress-custom {
    height: 8px;
    border-radius: 50px;
    background: var(--light-2);
    overflow: hidden;
}
.progress-custom .progress-bar {
    border-radius: 50px;
    transition: width .8s cubic-bezier(.4,0,.2,1);
}

/* ── Badge Levels ── */
.badge-nivel {
    padding: .35rem .75rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: .75rem;
    text-transform: uppercase;
    letter-spacing: .5px;
}
.badge-alto { background: rgba(16,185,129,.12); color: var(--success); }
.badge-medio { background: rgba(245,158,11,.12); color: var(--warning); }
.badge-bajo { background: rgba(239,68,68,.12); color: var(--danger); }
.badge-facil { background: rgba(16,185,129,.12); color: var(--success); }
.badge-media { background: rgba(245,158,11,.12); color: var(--warning); }
.badge-dificil { background: rgba(239,68,68,.12); color: var(--danger); }
.badge-diagnostico { background: rgba(30,58,95,.12); color: var(--primary); }
.badge-practica { background: rgba(14,165,233,.12); color: var(--secondary); }
.badge-ceneval { background: rgba(245,158,11,.12); color: var(--warning); }

/* ── Exam UI ── */
.exam-container {
    max-width: 800px;
    margin: 2rem auto;
}
.exam-header {
    background: var(--gradient-1);
    color: white;
    border-radius: var(--radius) var(--radius) 0 0;
    padding: 1.5rem;
}
.exam-header.practica { background: var(--gradient-2); }
.exam-header.ceneval { background: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%); }
.exam-body {
    background: var(--white);
    border: 1px solid var(--light-2);
    border-top: none;
    border-radius: 0 0 var(--radius) var(--radius);
    padding: 2rem;
}
.exam-context {
    background: rgba(30,58,95,.05);
    border-left: 4px solid var(--primary);
    padding: 1rem 1.25rem;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    margin-bottom: 1.5rem;
    font-size: .95rem;
    color: var(--dark-3);
}
.option-card {
    border: 2px solid var(--light-2);
    border-radius: var(--radius-sm);
    padding: 1rem 1.25rem;
    margin-bottom: .75rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: .75rem;
}
.option-card:hover { border-color: var(--primary-light); background: rgba(30,58,95,.04); }
.option-card.selected { border-color: var(--primary); background: rgba(30,58,95,.08); }
.option-card.correct { border-color: var(--success); background: rgba(16,185,129,.08); }
.option-card.incorrect { border-color: var(--danger); background: rgba(239,68,68,.08); }
.option-letter {
    width: 36px; height: 36px;
    border-radius: 50%;
    background: var(--light);
    display: flex; align-items: center; justify-content: center;
    font-weight: 700;
    color: var(--gray);
    flex-shrink: 0;
    transition: var(--transition);
}
.option-card.selected .option-letter { background: var(--primary); color: white; }
.option-card.correct .option-letter { background: var(--success); color: white; }
.option-card.incorrect .option-letter { background: var(--danger); color: white; }

/* ── Feedback Box ── */
.feedback-box {
    border-radius: var(--radius-sm);
    padding: 1.25rem;
    margin-top: 1.5rem;
    animation: slideUp .4s ease;
}
.feedback-correct {
    background: rgba(16,185,129,.08);
    border: 1px solid rgba(16,185,129,.2);
    color: #065f46;
}
.feedback-incorrect {
    background: rgba(239,68,68,.08);
    border: 1px solid rgba(239,68,68,.2);
    color: #991b1b;
}

/* ── Time Analysis ── */
.time-badge {
    display: inline-flex; align-items: center; gap: .35rem;
    padding: .3rem .7rem; border-radius: 50px;
    font-size: .8rem; font-weight: 600;
}
.time-good { background: rgba(16,185,129,.12); color: var(--success); }
.time-ok { background: rgba(245,158,11,.12); color: var(--warning); }
.time-slow { background: rgba(239,68,68,.12); color: var(--danger); }

/* ── Subscription Card ── */
.subscription-card {
    background: var(--white);
    border: 2px solid var(--light-2);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    text-align: center;
    max-width: 480px;
    margin: 0 auto;
    transition: var(--transition);
}
.subscription-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}
.subscription-price {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
}
.subscription-price small {
    font-size: 1rem;
    color: var(--gray);
    font-weight: 500;
}
.subscription-features {
    list-style: none; padding: 0; margin: 1.5rem 0;
    text-align: left;
}
.subscription-features li {
    padding: .6rem 0;
    border-bottom: 1px solid var(--light-2);
    display: flex; align-items: center; gap: .75rem;
    font-size: .95rem;
}
.subscription-features li i { color: var(--success); font-size: 1.1rem; }

/* ── Table ── */
.table-custom { border-radius: var(--radius); overflow: hidden; }
.table-custom thead th {
    background: var(--dark);
    color: white;
    font-weight: 600;
    font-size: .85rem;
    text-transform: uppercase;
    letter-spacing: .5px;
    padding: .9rem 1rem;
    border: none;
}
.table-custom tbody td { padding: .85rem 1rem; vertical-align: middle; border-color: var(--light-2); }
.table-custom tbody tr { transition: var(--transition); }
.table-custom tbody tr:hover { background: rgba(30,58,95,.04); }

/* ── Dashboard Section ── */
.section-title {
    font-weight: 700;
    font-size: 1.2rem;
    margin-bottom: 1.25rem;
    color: var(--dark);
    display: flex;
    align-items: center;
    gap: .5rem;
}
.section-title i { color: var(--primary); }

/* ── Filter Pills ── */
.filter-pills {
    display: flex; gap: .5rem; flex-wrap: wrap; margin-bottom: 1.5rem;
}
.filter-pill {
    padding: .4rem 1rem; border-radius: 50px;
    font-size: .85rem; font-weight: 600;
    text-decoration: none; transition: var(--transition);
    border: 1px solid var(--light-2); color: var(--gray);
    background: var(--white);
}
.filter-pill:hover { border-color: var(--primary); color: var(--primary); }
.filter-pill.active { background: var(--primary); color: white; border-color: var(--primary); }

/* ── Animations ── */
@keyframes slideUp {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
.animate-in { animation: slideUp .5s ease forwards; }

/* ── Timer ── */
.timer-display {
    font-size: 1.1rem;
    font-weight: 700;
    font-variant-numeric: tabular-nums;
}

/* ── Planes de suscripción ── */
.plan-card {
    position: relative;
    background: #fff;
    border: 1px solid #e5e7eb;
    border-radius: var(--radius-lg);
    padding: 2rem 1.75rem;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    transition: transform .25s ease, box-shadow .25s ease;
}
.plan-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.plan-card.featured { border: 2px solid var(--primary); box-shadow: var(--shadow-glow); }
.plan-badge {
    position: absolute;
    top: -12px; left: 50%;
    transform: translateX(-50%);
    background: var(--primary);
    color: #fff;
    font-size: .7rem;
    font-weight: 700;
    letter-spacing: .08em;
    padding: .3rem .9rem;
    border-radius: 999px;
}
.plan-name { font-weight: 700; font-size: 1.1rem; color: var(--primary); text-transform: uppercase; letter-spacing: .05em; }
.plan-price { font-size: 2.6rem; font-weight: 800; color: var(--dark); margin: .25rem 0 1.25rem; }
.plan-price span { font-size: .95rem; font-weight: 500; color: var(--gray); }
.plan-features { list-style: none; padding: 0; margin: 0 0 1.5rem; flex: 1; }
.plan-features li { display: flex; gap: .6rem; align-items: flex-start; padding: .45rem 0; font-size: .92rem; }
.plan-features li i { color: var(--success); margin-top: .15rem; }
.plan-features li.disabled { color: var(--gray-light); }
.plan-features li.disabled i { color: var(--gray-light); }

/* ══════════════════════════════════════════════
   DISEÑO WEB RESPONSIVO (RWD) & ADAPTABILIDAD UNIVERSAL
   ══════════════════════════════════════════════ */

/* ── Mejoras Universales de Interacción y Fluidéz ── */
html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    overflow-x: hidden;
    width: 100%;
}

/* Touch Targets accesibles (mínimo 44px de altura) */
button, 
.btn, 
.form-control, 
.form-select, 
.option-card, 
.nav-link {
    min-height: 44px;
}

.table-responsive {
    -webkit-overflow-scrolling: touch;
    width: 100%;
    margin-bottom: 1rem;
    overflow-x: auto;
}

/* Contenedor fluido de exámenes */
.exam-container {
    width: 100%;
    max-width: min(880px, 95vw);
    margin: clamp(1rem, 2.5vw, 2.5rem) auto;
    padding: 0 clamp(0.5rem, 1.5vw, 1.5rem);
}

.exam-header {
    padding: clamp(1rem, 2.5vw, 1.75rem);
}

.exam-body {
    padding: clamp(1.25rem, 3vw, 2.25rem);
}

.option-card {
    min-height: 52px;
    padding: clamp(0.85rem, 1.5vw, 1.25rem);
}

/* Tipografía fluida en encabezados */
.landing-title {
    font-size: clamp(2rem, 5vw + 1rem, 4rem) !important;
    line-height: 1.15;
}

.landing-subtitle {
    font-size: clamp(1rem, 1.8vw, 1.35rem) !important;
}

/* ── BREAKPOINT 1: Móviles Pequeños y Medianos (<= 576px) ── */
@media (max-width: 576px) {
    .container, .container-fluid {
        padding-left: 0.85rem;
        padding-right: 0.85rem;
    }

    /* Auth pages */
    .auth-card {
        margin: 0.75rem;
        padding: 1.5rem 1.25rem;
        border-radius: var(--radius);
        max-width: 100%;
    }
    
    .auth-wrapper::before, .auth-wrapper::after {
        display: none; /* Mejor rendimiento en móviles */
    }

    /* Exam UI adaptada a una mano */
    .exam-header .d-flex {
        flex-direction: column;
        align-items: flex-start !important;
        gap: 0.75rem;
    }

    .exam-header .text-end {
        text-align: left !important;
        display: flex;
        align-items: baseline;
        gap: 0.5rem;
    }

    #numPregunta {
        font-size: 1.25rem !important;
    }

    .exam-body .d-flex.justify-content-between.mt-4 {
        flex-direction: column-reverse;
        gap: 0.75rem;
    }

    .exam-body .d-flex.justify-content-between.mt-4 button,
    .exam-body .d-flex.justify-content-between.mt-4 a,
    .exam-body .d-flex.justify-content-between.mt-4 form {
        width: 100%;
    }

    .exam-body .d-flex.justify-content-between.mt-4 button {
        width: 100% !important;
    }

    /* Opciones apiladas */
    .option-card {
        padding: 0.85rem 1rem;
        font-size: 0.95rem;
    }

    .option-letter {
        width: 32px;
        height: 32px;
        font-size: 0.9rem;
    }

    /* Stat Cards */
    .stat-card {
        padding: 1rem;
    }
    .stat-card .stat-value {
        font-size: 1.45rem;
    }
    .stat-card .stat-label {
        font-size: 0.8rem;
    }

    /* Navbar en móvil */
    .navbar-brand .brand-text {
        font-size: 1.05rem;
    }
    
    .nav-user-badge {
        font-size: 0.78rem;
        padding: 0.25rem 0.65rem;
    }

    /* Tablas responsivas en admin y resultados */
    table thead th, table tbody td {
        font-size: 0.85rem;
        padding: 0.6rem 0.5rem;
    }

    /* Landing grid */
    .landing-features {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    /* Modales */
    .modal-dialog {
        margin: 0.75rem;
    }
}

/* ── BREAKPOINT 2: Tablets y Dispositivos Verticales (577px a 768px) ── */
@media (min-width: 577px) and (max-width: 768px) {
    .auth-card {
        padding: 2rem 1.75rem;
        max-width: 440px;
    }

    .landing-features {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.25rem;
    }

    .stat-card .stat-value {
        font-size: 1.6rem;
    }

    .exam-body {
        padding: 1.75rem;
    }
}

/* ── BREAKPOINT 3: Tablets Horizontales y Pantallas Medianas (769px a 1024px) ── */
@media (min-width: 769px) and (max-width: 1024px) {
    .container {
        max-width: 95%;
    }

    .landing-features {
        grid-template-columns: repeat(2, 1fr);
    }

    .mode-card {
        padding: 1.35rem;
    }
}

/* ── BREAKPOINT 4: Laptops y Monitores Estándar (1025px a 1440px) ── */
@media (min-width: 1025px) and (max-width: 1440px) {
    .container-lg, .container-xl {
        max-width: 1200px;
    }
}

/* ── BREAKPOINT 5: Monitores Anchos y Ultra-wide (>= 1441px) ── */
@media (min-width: 1441px) {
    .container, .container-lg, .container-xl {
        max-width: 1360px;
    }

    .page-main-content {
        max-width: 1600px;
        margin: 0 auto;
    }

    .landing-hero-content {
        max-width: 1200px;
        margin: 0 auto;
    }

    .exam-container {
        max-width: 960px;
    }

    .exam-body {
        padding: 2.75rem;
    }

    .option-card {
        padding: 1.25rem 1.5rem;
        font-size: 1.05rem;
    }
}