* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f5f6f8;
    color: #333;
}

.main-header {
    background-color: #1a1a1a;
    color: #fff;
    text-align: center;
    padding: 2.5rem 1rem;
    box-shadow: 0 4px 10px rgba(0,0,0,0.15);
}

.brand-title {
    color: #f1c40f;
    font-size: 2.4rem;
    font-weight: 700;
    letter-spacing: 1px;
}

.brand-subtitle {
    color: #ccc;
    font-size: 0.9rem;
    letter-spacing: 3px;
    margin-top: 0.2rem;
}

.gold-line {
    width: 120px;
    height: 2px;
    background-color: #f1c40f;
    margin: 0.8rem auto;
}

.panel-tag {
    color: #a0aec0;
    font-size: 0.95rem;
    font-style: italic;
}

.nav-back-container {
    max-width: 1200px;
    margin: 1.5rem auto 0 auto;
    padding: 0 1rem;
}

.btn-back {
    text-decoration: none;
    color: #4a5568;
    font-weight: bold;
    font-size: 0.95rem;
    transition: color 0.2s;
}

.btn-back:hover {
    color: #1a1a1a;
}

.container {
    max-width: 1200px;
    margin: 1.5rem auto 3rem auto;
    padding: 0 1rem;
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

@media (min-width: 768px) {
    .container {
        grid-template-columns: 360px 1fr;
    }
}

.form-section, .list-section {
    background: #fff;
    padding: 1.8rem;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

h2 {
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
    color: #1a1a1a;
    border-bottom: 2px solid #edf2f7;
    padding-bottom: 0.5rem;
}

.form-group {
    margin-bottom: 1.2rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.4rem;
    font-weight: 600;
    font-size: 0.9rem;
    color: #4a5568;
}

.form-group input, .form-group select {
    width: 100%;
    padding: 0.7rem;
    border: 1px solid #cbd5e0;
    border-radius: 5px;
    font-size: 0.95rem;
}

.btn-primary {
    width: 100%;
    background-color: #2ecc71;
    color: #fff;
    padding: 0.8rem;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    box-shadow: 0 4px 6px rgba(46, 204, 113, 0.2);
    transition: background 0.2s;
}

.btn-primary:hover {
    background-color: #27ae60;
}

.tournament-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.tournament-card {
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 6px;
    padding: 1.2rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.02);
}

.tournament-card h3 {
    font-size: 1.1rem;
    margin: 0.8rem 0 0.5rem 0;
}

.tournament-card p {
    font-size: 0.9rem;
    color: #718096;
    margin-bottom: 0.3rem;
}

.card-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
}

.btn-secondary, .btn-danger {
    flex: 1;
    padding: 0.5rem;
    border: none;
    border-radius: 4px;
    font-size: 0.85rem;
    cursor: pointer;
}

.btn-secondary { background: #e2e8f0; color: #4a5568; }
.btn-danger { background: #fed7d7; color: #c53030; }

.badge {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: bold;
    text-transform: uppercase;
}
.badge-blitz { background-color: #feebc8; color: #c05621; }
#boardProblemas {
    display: inline-block !important;
    overflow: hidden !important;
}