:root {
    color-scheme: light;
    --bg: #f5f2ea;
    --surface: #ffffff;
    --text: #1c1a15;
    --muted: #6b5f51;
    --accent: #e67300;
    --border: #e6dfd5;
}

:root[data-theme="dark"] {
    color-scheme: dark;
    --bg: #0f1412;
    --surface: #171d19;
    --text: #f5f1e8;
    --muted: #b8ad9f;
    --accent: #ffb452;
    --border: #2a332d;
}

* {
    box-sizing: border-box;
}

body {
    font-family: "Trebuchet MS", "Gill Sans", sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: radial-gradient(circle at top, rgba(255, 181, 82, 0.25), transparent 45%), var(--bg);
    color: var(--text);
    margin: 0;
    padding: 24px;
}

#app {
    text-align: center;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 32px 28px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
    max-width: 520px;
    width: 100%;
}

#app h1 {
    margin: 0 0 12px;
    letter-spacing: 0.5px;
}

#theme-toggle {
    border: 1px solid var(--border);
    background: transparent;
    color: var(--muted);
    border-radius: 999px;
    padding: 6px 16px;
    font-size: 14px;
    cursor: pointer;
    margin-bottom: 16px;
    transition: transform 0.15s ease, color 0.2s ease, border-color 0.2s ease;
}

#numbers-container {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 12px;
    margin: 20px 0;
}

.numbers-row {
    display: flex;
    gap: 12px;
    justify-content: center;
    width: 100%;
}

.numbers-row::before {
    content: "Set " attr(data-set);
    font-size: 12px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--muted);
    margin-right: 8px;
    align-self: center;
}

lotto-ball {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 20px;
    font-weight: bold;
    color: white;
}

#generate-btn {
    padding: 12px 22px;
    font-size: 16px;
    cursor: pointer;
    border-radius: 12px;
    border: none;
    background: var(--accent);
    color: #1c1a15;
    transition: transform 0.15s ease, filter 0.2s ease;
}

#generate-btn:hover,
#theme-toggle:hover {
    transform: translateY(-1px);
}