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

body {
    font-family: 'Poppins', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

/* Header Styles */
header {
    text-align: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid #eee;
}

h1 {
    color: #667eea;
    font-size: 2.5rem;
    margin-bottom: 10px;
}

.back-link {
    display: inline-block;
    margin-bottom: 20px;
    color: #667eea;
    text-decoration: none;
    font-weight: bold;
    transition: opacity 0.3s ease;
}

.back-link:hover {
    opacity: 0.7;
}

/* Button Styles - Alle gleich schön */
.btn {
    display: inline-block;
    padding: 12px 25px;
    margin: 8px;
    text-decoration: none;
    border-radius: 25px;
    font-weight: bold;
    text-align: center;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 1rem;
    min-width: 120px;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.btn.primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn.secondary {
    background: #6c757d;
    color: white;
}

.btn.success {
    background: #28a745;
    color: white;
}

.btn.accent {
    background: #ff6b6b;
    color: white;
}

.btn.warning {
    background: #ffc107;
    color: #212529;
}

.btn.info {
    background: #17a2b8;
    color: white;
}

/* Challenge Card - Klassische Kästen */
.challenge-card {
    background: white;
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    border-left: 4px solid #667eea;
    transition: all 0.3s ease;
    margin-bottom: 15px;
}

.challenge-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
    border-left: 4px solid #ff6b6b;
}

.challenge-card.completed {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
    color: white;
    border-left: none;
}

.challenge-card.completed .challenge-category {
    background: rgba(255, 255, 255, 0.2);
}

.challenge-category {
    display: inline-block;
    background: #667eea;
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    margin-bottom: 10px;
}

.challenge-text {
    font-size: 1.1rem;
    margin-bottom: 15px;
    line-height: 1.5;
}

.challenge-difficulty {
    font-size: 0.9rem;
    margin-bottom: 15px;
    opacity: 0.8;
}

.featured {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-left: none;
}

.featured .challenge-category {
    background: rgba(255, 255, 255, 0.2);
}

/* Search Section */
.search-section {
    margin-bottom: 30px;
    background: #f8f9fa;
    padding: 20px;
    border-radius: 15px;
}

.search-box {
    width: 100%;
    padding: 15px;
    border-radius: 25px;
    border: 2px solid #ddd;
    font-size: 1rem;
    margin-bottom: 15px;
}

.search-box:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.filter-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
}

.filter-btn {
    padding: 10px 20px;
    border-radius: 25px;
    border: 2px solid #ddd;
    background: white;
    color: #666;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.filter-btn:hover,
.filter-btn.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
    box-shadow: 0 3px 10px rgba(102, 126, 234, 0.3);
}

/* Challenges Grid */
.challenges-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 15px;
    margin-top: 20px;
}

/* Streak Display */
.streak-display {
    background: linear-gradient(135deg, #ff6b6b, #ffa502);
    color: white;
    padding: 20px;
    border-radius: 15px;
    margin: 20px 0;
    text-align: center;
    box-shadow: 0 5px 15px rgba(255, 107, 107, 0.3);
}

.streak-display h3 {
    margin-bottom: 10px;
    font-size: 1.2rem;
}

.streak-numbers {
    font-size: 2rem;
    font-weight: bold;
}

/* Action Buttons Grid */
.action-buttons {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin: 30px 0;
}

.action-card {
    background: white;
    padding: 20px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 1px solid #eee;
}

.action-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.action-icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.action-card h3 {
    color: #667eea;
    margin-bottom: 10px;
}

/* Stats Section */
.stats-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
    margin: 30px 0;
}

.stat-card {
    background: white;
    padding: 20px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    border: 1px solid #eee;
}

.stat-number {
    font-size: 2rem;
    font-weight: bold;
    color: #667eea;
    margin-bottom: 5px;
}

.stat-label {
    color: #666;
    font-size: 0.9rem;
}

/* Categories Grid */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.category-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 1px solid #eee;
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.category-header {
    padding: 20px;
    color: white;
    text-align: center;
}

.category-header h3 {
    margin: 10px 0 5px 0;
}

.category-content {
    padding: 20px;
}

.category-content p {
    color: #666;
    margin-bottom: 15px;
    font-size: 0.95rem;
}

/* Tips Section */
.tips {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 15px;
    margin-top: 30px;
}

.tips h3 {
    color: #667eea;
    margin-bottom: 15px;
}

.tips ul {
    padding-left: 20px;
}

.tips li {
    margin: 10px 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 20px;
        margin: 10px;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .filter-buttons {
        justify-content: center;
    }
    
    .action-buttons {
        grid-template-columns: 1fr;
    }
    
    .stats-section {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 480px) {
    body {
        padding: 10px;
    }
    
    .container {
        padding: 15px;
    }
    
    .btn {
        padding: 10px 15px;
        font-size: 0.9rem;
        margin: 5px;
    }
    
    .filter-btn {
        padding: 8px 15px;
        font-size: 0.9rem;
    }
    
    .stats-section {
        grid-template-columns: 1fr;
    }
}