body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #f0f2f5;
}

.lang-switch {
    position: absolute;
    top: 20px;
    right: 20px;
}

#lang-btn {
    padding: 8px 16px;
    font-size: 0.9rem;
    background-color: white;
    color: #333;
    border: 1px solid #ddd;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.container {
    text-align: center;
    background: white;
    padding: 3rem;
    border-radius: 20px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    width: 90%;
    max-width: 500px;
}

h1 {
    color: #333;
    margin-bottom: 2rem;
}

.ball-container {
    display: flex;
    gap: 15px;
    margin-bottom: 2.5rem;
    justify-content: center;
    min-height: 60px;
    flex-wrap: wrap;
}

.ball {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 1.2rem;
    color: white;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
    animation: popIn 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.ball.placeholder {
    background-color: #e0e0e0;
    color: #999;
}

@keyframes popIn {
    0% { transform: scale(0); opacity: 0; }
    100% { transform: scale(1); opacity: 1; }
}

button {
    padding: 12px 30px;
    font-size: 1.1rem;
    font-weight: 600;
    background-color: #4a90e2;
    color: white;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

button:hover {
    background-color: #357abd;
}

button:active {
    transform: scale(0.95);
}

.color-1 { background-color: #fbc400; }
.color-11 { background-color: #69c8f2; }
.color-21 { background-color: #ff7272; }
.color-31 { background-color: #aaa; }
.color-41 { background-color: #b0d840; }