:root {
    color-scheme: dark;
    --background: #111827;
    --surface: #1f2937;
    --text: #e5edf7;
    --muted: #aebdd0;
    --border: #4b6078;
    --input: #111827;
    --accent: #93c5fd;
    --button: #2563eb;
    --button-hover: #1d4ed8;
    --arena: #172234;
    --arena-ink: #d4deec;
    --shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

:root[data-theme="light"] {
    color-scheme: light;
    --background: #f4f4f9;
    --surface: #ffffff;
    --text: #26364a;
    --muted: #536477;
    --border: #a3afbf;
    --input: #ffffff;
    --accent: #1d4ed8;
    --arena: #f0f0f0;
    --arena-ink: #18212f;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

body {
    background: var(--background);
    color: var(--text);
    font-family: Arial, sans-serif;
}

#theme-toggle {
    position: fixed;
    top: 12px;
    right: 12px;
    z-index: 1400;
    width: auto;
    min-height: 44px;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: 24px;
    background: var(--surface);
    color: var(--text);
    box-shadow: var(--shadow);
    font: 14px Arial, sans-serif;
    cursor: pointer;
}

#theme-toggle:hover { border-color: var(--accent); }

:where(button, a, input):focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 3px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
    border: 0;
}