/* General styles */
:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
    padding: 2rem 0;
}

/* Centered pages */
.auth-page main,
.home-page main {
    display: flex;
    align-items: center;
}

/* Card styles */
.card {
    border: none;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    margin-bottom: 1rem;
}

.card-header {
    background-color: var(--dark-color);
    color: white;
    border-bottom: none;
}

/* Form styles */
.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: none;
}

/* Button styles */
.btn {
    border-radius: 4px;
    padding: 0.5rem 1rem;
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-primary:hover {
    background-color: #0056b3;
    border-color: #0056b3;
}

/* Alert styles */
.alert {
    border: none;
    border-radius: 4px;
    margin-bottom: 1rem;
}

/* Table styles */
.table {
    margin-bottom: 0;
}

.table th {
    border-top: none;
    font-weight: 600;
}

/* Leaderboard styles */
.leaderboard-row {
    transition: none;
}

/* Profile styles */
.profile-header {
    text-align: center;
    padding: 2rem;
}

/* Challenge details */
.challenge-card {
    transition: none;
}

.challenge-card.solved {
    border-left: 4px solid var(--success-color);
}

/* File download button */
.file-download-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

/* Hint styles */
.hint-card {
    background-color: var(--dark-color);
    color: white;
}

/* Loading spinner */
.spinner-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

/* Footer styles */
.footer {
    margin-top: auto;
    padding: 1rem 0;
    background-color: var(--dark-color);
    color: var(--light-color);
}

.social-links a {
    text-decoration: none;
    font-size: 1.2rem;
}

.social-links a:hover {
    opacity: 0.8;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    .card {
        margin-bottom: 1rem;
    }
    
    main {
        padding: 1rem 0;
    }
}