/* Challenges Main Layout */
.challenges-main {
    min-height: calc(100vh - 70px);
    padding: 40px 0;
    background: #E3F0E7; /* Mint Page Background */
}

/* Mint Header Band */
.challenges-header {
    background: linear-gradient(180deg, #E8F3EE 0%, #E3F0E7 60%, #DDEBE3 100%);
    padding: 20px 0;
    margin-bottom: 40px;
    text-align: center;
    color: #0F4A46; /* Dark Teal */
}

.challenges-header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin: 0;
}

.challenges-header {
    text-align: center;
    margin-bottom: 60px;
}

.challenges-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: #0F4A46; /* Dark Teal */
}

.challenges-header p {
    font-size: 1.2rem;
    color: #335A57; /* Muted Text */
    max-width: 600px;
    margin: 0 auto;
    font-weight: 500;
}

/* Layout */
.challenges-layout {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 60px;
}

/* Challenges Column */
.challenges-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
    flex-wrap: wrap;
    gap: 16px;
}

.challenges-controls h2 {
    font-size: 24px;
    font-weight: 600;
    color: #0F4A46; /* Dark Teal */
}

.filter-toggle {
    padding: 8px 16px;
    border: 1px solid #D9E6DF; /* Border/Divider */
    background: #FFFFFF; /* Card/Surface */
    color: #335A57; /* Muted Text */
    border-radius: 20px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.filter-toggle:hover {
    border-color: #2A6E7B; /* Primary Teal */
    color: #0F4A46; /* Dark Teal */
}

.filter-toggle.active {
    background: #2A6E7B; /* Primary Teal */
    color: #FFFFFF; /* Button Text on Teal */
    border-color: #2A6E7B; /* Primary Teal */
}

/* Challenges Grid */
.challenges-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
}

.challenge-card {
    background: #FFFFFF; /* Card/Surface */
    border: 1px solid #D9E6DF; /* Border/Divider */
    border-radius: 20px;
    padding: 24px;
    box-shadow: 0 10px 24px rgba(2, 6, 23, 0.08);
    transition: all 0.3s ease;
    cursor: pointer;
}

.challenge-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 16px 32px rgba(42, 110, 123, 0.15);
    border-color: #2A6E7B; /* Primary Teal */
}

.challenge-header {
    margin-bottom: 16px;
}

.challenge-title {
    font-size: 18px;
    font-weight: 600;
    color: #0F4A46; /* Dark Teal */
    margin-bottom: 8px;
}

.challenge-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.difficulty-badge {
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 600;
}

.difficulty-badge.beginner {
    background: #22c55e;
    color: #ffffff;
}

.difficulty-badge.intermediate {
    background: #f59e0b;
    color: #ffffff;
}

.difficulty-badge.advanced {
    background: #dc2626;
    color: #ffffff;
}

.difficulty-badge.expert {
    background: #7c3aed;
    color: #ffffff;
}

.solved-count {
    color: #335A57; /* Muted Text */
    font-size: 14px;
}

.challenge-description {
    color: #335A57; /* Muted Text */
    font-size: 14px;
    line-height: 1.5;
    margin-bottom: 20px;
}

.challenge-actions {
    display: flex;
    gap: 8px;
}

.challenge-actions .btn {
    flex: 1;
    padding: 10px 16px;
    font-size: 14px;
}

.challenge-card.enrolled {
    border-color: #10b981;
    background: #ecfdf5;
}

.challenge-card.enrolled .challenge-title::after {
    content: ' ✓';
    color: #10b981;
}

/* Leaderboard Column */
.leaderboard-section {
    background: #FFFFFF; /* Card/Surface */
    border: 1px solid #D9E6DF; /* Border/Divider */
    border-radius: 20px;
    padding: 24px;
    box-shadow: 0 10px 24px rgba(42, 110, 123, 0.08);
    height: fit-content;
    position: sticky;
    top: 100px;
}

.leaderboard-section h2 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 24px;
    color: #0F4A46; /* Dark Teal */
    text-align: center;
}

.leaderboard-table {
    width: 100%;
}

.table-header {
    display: grid;
    grid-template-columns: 50px 1fr 80px 60px;
    gap: 12px;
    padding: 12px 0;
    border-bottom: 1px solid #e2e8f0;
    font-weight: 600;
    color: #64748b;
    font-size: 14px;
}

.table-body {
    display: flex;
    flex-direction: column;
}

.leaderboard-entry {
    display: grid;
    grid-template-columns: 50px 1fr 80px 60px;
    gap: 12px;
    padding: 16px 0;
    border-bottom: 1px solid #f3f4f6;
    transition: all 0.3s ease;
    cursor: pointer;
}

.leaderboard-entry:hover {
    background: #F1F7F4; /* Mint Light */
    transform: translateX(4px);
}

.leaderboard-entry:last-child {
    border-bottom: none;
}

.rank {
    font-weight: 700;
    color: #0F4A46; /* Dark Teal */
    text-align: center;
}

.rank.first {
    color: #ffd700;
}

.rank.second {
    color: #c0c0c0;
}

.rank.third {
    color: #cd7f32;
}

.name {
    color: #0F4A46; /* Dark Teal */
    font-weight: 600;
}

.expertise {
    display: flex;
    flex-wrap: wrap;
    gap: 2px;
}

.expertise .tag {
    font-size: 10px;
}

.solved {
    text-align: center;
    font-weight: 600;
    color: #22c55e;
}

/* Connect Modal */
.challenge-info {
    background: #F1F7F4; /* Mint Light */
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 24px;
    border: 1px solid #D9E6DF; /* Border/Divider */
}

.challenge-info h3 {
    color: #0F4A46; /* Dark Teal */
    margin-bottom: 8px;
}

.challenge-info p {
    color: #335A57; /* Muted Text */
    font-size: 14px;
}

.collaborators-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}

.collaborator-card {
    background: #ffffff;
    border: 1px solid #D9E6DF; /* Border/Divider */
    border-radius: 8px;
    padding: 16px;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
}

.collaborator-card:hover {
    border-color: #2A6E7B; /* Primary Teal */
    transform: translateY(-2px);
}

.collaborator-card.selected {
    border-color: #10b981;
    background: #ecfdf5;
}

.collaborator-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, #F1F7F4 0%, #D9E6DF 100%);
    margin: 0 auto 12px;
    position: relative;
}

.collaborator-avatar::after {
    content: '👨‍⚕️';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 20px;
}

.collaborator-name {
    font-weight: 600;
    color: #0F4A46; /* Dark Teal */
    margin-bottom: 8px;
}

.collaborator-stats {
    color: #22c55e;
    font-size: 14px;
    margin-bottom: 8px;
}

.collaborator-expertise {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    justify-content: center;
}

.message-section {
    border-top: 1px solid #D9E6DF; /* Border/Divider */
    padding-top: 24px;
}

.message-section h3 {
    margin-bottom: 16px;
    color: #0F4A46; /* Dark Teal */
}

/* Profile Drawer */
.profile-content {
    text-align: center;
}

.profile-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, #F1F7F4 0%, #D9E6DF 100%);
    margin: 0 auto 20px;
    position: relative;
}

.profile-avatar::after {
    content: '👨‍⚕️';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 32px;
}

.profile-name {
    font-size: 24px;
    font-weight: 600;
    color: #0F4A46; /* Dark Teal */
    margin-bottom: 8px;
}

.profile-role {
    color: #335A57; /* Muted Text */
    margin-bottom: 16px;
}

.profile-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 24px;
}

.stat-item {
    text-align: center;
}

.stat-value {
    font-size: 24px;
    font-weight: 700;
    color: #22c55e;
}

.stat-label {
    color: #999;
    font-size: 14px;
}

.profile-expertise {
    margin-bottom: 24px;
}

.profile-expertise h4 {
    color: #0F4A46; /* Dark Teal */
    margin-bottom: 12px;
}

.profile-bio {
    text-align: left;
    margin-bottom: 24px;
}

.profile-bio h4 {
    color: #0F4A46; /* Dark Teal */
    margin-bottom: 12px;
}

.profile-bio p {
    color: #335A57; /* Muted Text */
    line-height: 1.5;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .challenges-layout {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .leaderboard-section {
        position: static;
    }
}

@media (max-width: 768px) {
    .challenges-main {
        padding: 20px 0;
    }
    
    .challenges-header h1 {
        font-size: 2rem;
    }
    
    .challenges-controls {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .challenges-grid {
        grid-template-columns: 1fr;
    }
    
    .table-header,
    .leaderboard-entry {
        grid-template-columns: 40px 1fr 60px 50px;
        gap: 8px;
    }
    
    .collaborators-grid {
        grid-template-columns: 1fr;
    }
    
    .profile-stats {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .challenge-actions {
        flex-direction: column;
    }
    
    .table-header,
    .leaderboard-entry {
        font-size: 12px;
        padding: 12px 0;
    }
    
    .expertise {
        display: none;
    }
}