.light-theme{--bg:#f0f4f8;--text:#102a43;--accent:#0b6efd;--btn-bg:#fff;--btn-text:#102a43}.dark-theme{--bg:#071026;--text:#e6f0ff;--accent:#7aa2ff;--btn-bg:#0f1724;--btn-text:#e6f0ff}#__next,body,html{height:100%;margin:0;padding:0}body{background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;transition:background .16s ease,color .16s ease}.center-container{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:1rem;box-sizing:border-box;flex-direction:column;gap:1rem}.title{text-align:center;margin:0;font-size:clamp(1.25rem,2.5vw + .5rem,2rem);max-width:900px;line-height:1.2}.theme-toggle{padding:.5rem .75rem;border-radius:6px;border:1px solid rgba(0,0,0,.08);background:var(--btn-bg);color:var(--btn-text);cursor:pointer;box-shadow:0 1px 2px rgba(0,0,0,.04);font-size:.95rem}.theme-toggle:focus{outline:2px solid var(--accent);outline-offset:2px}.controls-row{display:flex;gap:.5rem;align-items:center}