:root {
    --background-color: #f8f9fa;
    --primary-color: #4a90e2;
    --text-color: #212529;
    --container-background: #ffffff;
    --number-bg: #e9ecef;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --background-color: #121212;
    --primary-color: #1DB954;
    --text-color: #f8f9fa;
    --container-background: #1e1e1e;
    --number-bg: #2d2d2d;
    --shadow-color: rgba(0, 0, 0, 0.5);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    background-color: var(--container-background);
    padding: 2.5rem;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 30px var(--shadow-color);
    width: 90%;
    max-width: 400px;
    position: relative;
    transition: background-color 0.3s, box-shadow 0.3s;
}

.theme-toggle {
    position: absolute;
    top: 15px;
    right: 15px;
}

#theme-btn {
    background: none;
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    padding: 5px 12px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s;
}

#theme-btn:hover {
    background-color: var(--primary-color);
    color: white;
}

h1 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
}

#generate {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 1rem 2rem;
    font-size: 1.1rem;
    border-radius: 50px;
    cursor: pointer;
    transition: transform 0.2s, background-color 0.3s;
}

#generate:active {
    transform: scale(0.95);
}

.numbers-container {
    display: flex;
    justify-content: center;
    gap: 0.8rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.number {
    background-color: var(--number-bg);
    width: 45px;
    height: 45px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
    font-weight: bold;
    color: white;
    text-shadow: 0 1px 2px rgba(0,0,0,0.2);
    transition: all 0.3s ease;
}

.number.drawing {
    animation: spin 0.2s infinite linear;
    background-color: var(--number-bg) !important;
    color: transparent !important;
    border: 2px dashed var(--primary-color);
}

@keyframes spin {
    0% { transform: rotate(0deg) scale(1); }
    50% { transform: rotate(180deg) scale(1.1); }
    100% { transform: rotate(360deg) scale(1); }
}

.number.reveal {
    animation: popIn 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

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

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

.bonus-separator {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--text-color);
    margin: 0 0.2rem;
    opacity: 0;
    transition: opacity 0.3s;
}

.bonus-separator.visible {
    opacity: 1;
}