:root {
    --bg-color: #ffffff;
    --text-color: #333333;
    --container-bg: #f8f9fa;
    --ball-bg: #e9ecef;
    --ball-text: #333333;
    --primary-btn: #007bff;
    --primary-btn-hover: #0056b3;
    --secondary-btn: #6c757d;
    --secondary-btn-hover: #5a6268;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

body.dark-mode {
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --container-bg: #1e1e1e;
    --ball-bg: #333333;
    --ball-text: #ffffff;
    --primary-btn: #3700b3;
    --primary-btn-hover: #6200ee;
    --secondary-btn: #444444;
    --secondary-btn-hover: #666666;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.5);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s, color 0.3s;
}

body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, 'Helvetica Neue', 'Segoe UI', 'Apple SD Gothic Neo', 'Noto Sans KR', 'Malgun Gothic', 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    background-color: var(--container-bg);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    text-align: center;
    width: 90%;
    max-width: 500px;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

h1 {
    font-size: 1.5rem;
}

.lotto-numbers {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.ball {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--ball-bg);
    color: var(--ball-text);
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 1.2rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    transition: transform 0.2s;
}

.ball:hover {
    transform: scale(1.1);
}

/* 로또 번호대별 색상 */
.ball.range-1 { background-color: #fbc400; color: #fff; }
.ball.range-10 { background-color: #69c8f2; color: #fff; }
.ball.range-20 { background-color: #ff7272; color: #fff; }
.ball.range-30 { background-color: #aaa; color: #fff; }
.ball.range-40 { background-color: #b0d840; color: #fff; }

button {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-weight: bold;
    transition: opacity 0.2s;
}

.btn-primary {
    background-color: var(--primary-btn);
    color: white;
    width: 100%;
    font-size: 1.1rem;
}

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

.btn-secondary {
    background-color: var(--secondary-btn);
    color: white;
    font-size: 0.8rem;
}

.btn-secondary:hover {
    background-color: var(--secondary-btn-hover);
}