.spark{position:absolute;width:8px;height:8px;border-radius:999px;background:#fff;opacity:.65;box-shadow:0 0 14px currentColor;animation:float 9s linear infinite}@keyframes float{0%{transform:translateY(120vh) translateX(0);opacity:0}10%{opacity:.7}to{transform:translateY(-20vh) translateX(40px);opacity:0}}.topbar{display:flex;align-items:center;gap:16px;padding:18px 24px;border-bottom:1px solid hsla(0,0%,100%,.12);position:-webkit-sticky;position:sticky;top:0;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);background:rgba(11,18,32,.7)}.topbar h1{margin:0;font-size:20px}.brand{color:var(--accent,#67e8f9);text-decoration:none;font-weight:600}.theme-toggle{margin-left:auto;background:transparent;color:var(--text,#e6f1ff);border:1px solid hsla(0,0%,100%,.2);border-radius:10px;padding:6px 10px;cursor:pointer;font-weight:600}.theme-toggle:hover{border-color:var(--accent,#67e8f9);color:var(--accent,#67e8f9)}