:root {
    --bg: #f0f2f5;
    --bg-accent: #e4e7ec;
    --card: #ffffff;
    --text: #1f2933;
    --muted: #52616b;
    --primary: #007bff;
    --primary-hover: #0056b3;
    --chip: #4caf50;
    --shadow: 0 12px 30px rgba(15, 23, 42, 0.12);
}

body.dark {
    --bg: #0f172a;
    --bg-accent: #1f2937;
    --card: #111827;
    --text: #e2e8f0;
    --muted: #94a3b8;
    --primary: #38bdf8;
    --primary-hover: #0ea5e9;
    --chip: #22c55e;
    --shadow: 0 12px 30px rgba(2, 6, 23, 0.5);
}

body {
    font-family: Arial, sans-serif;
    background: radial-gradient(circle at top, var(--bg-accent), var(--bg));
    color: var(--text);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    transition: background 0.3s ease, color 0.3s ease;
}

.container {
    text-align: center;
    background-color: var(--card);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    min-width: 320px;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

h1 {
    margin: 0;
    color: var(--text);
}

.lotto-numbers {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.lotto-number {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
    font-weight: bold;
    color: white;
    background-color: var(--chip);
}

#generate-btn {
    padding: 0.8rem 1.5rem;
    font-size: 1rem;
    color: white;
    background-color: var(--primary);
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

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

.theme-toggle {
    padding: 0.5rem 0.9rem;
    font-size: 0.9rem;
    color: var(--text);
    background-color: transparent;
    border: 1px solid var(--muted);
    border-radius: 999px;
    cursor: pointer;
    transition: border-color 0.3s ease, color 0.3s ease, background-color 0.3s ease;
}

.theme-toggle:hover {
    border-color: var(--text);
    background-color: rgba(127, 127, 127, 0.12);
}