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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

nav a {
    color: white;
    text-decoration: none;
    margin: 0 1rem;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    transition: background-color 0.3s;
}

nav a:hover {
    background-color: rgba(255,255,255,0.2);
}

main {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
}

section {
    margin-bottom: 3rem;
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

h2 {
    color: #667eea;
    margin-bottom: 1.5rem;
    font-size: 1.8rem;
}

.pattern-card, .circle-card {
    border: 1px solid #e9ecef;
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.pattern-card:hover, .circle-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.1);
}

.pattern-card h3, .circle-card h3 {
    color: #495057;
    margin-bottom: 0.5rem;
}

.pattern-meta, .circle-meta {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.pattern-meta span, .circle-meta span {
    background: #e9ecef;
    padding: 0.3rem 0.8rem;
    border-radius: 15px;
    font-size: 0.9rem;
    color: #495057;
}

.difficulty {
    background: linear-gradient(45deg, #ff6b6b, #ffa500) !important;
    color: white !important;
}

.xp {
    background: linear-gradient(45deg, #4ecdc4, #44a08d) !important;
    color: white !important;
}

.leaderboard-entry {
    display: flex;
    align-items: center;
    padding: 1rem;
    border: 1px solid #e9ecef;
    border-radius: 8px;
    margin-bottom: 0.5rem;
    background: linear-gradient(90deg, #f8f9fa, white);
}

.rank {
    font-weight: bold;
    font-size: 1.2rem;
    color: #667eea;
    min-width: 3rem;
}

.name {
    flex: 1;
    font-weight: 600;
    margin-left: 1rem;
}

.level {
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    padding: 0.3rem 0.8rem;
    border-radius: 15px;
    font-size: 0.9rem;
    margin-right: 1rem;
}

.xp {
    color: #495057;
    font-weight: 500;
}