*,*:before,*:after{box-sizing:border-box}body{margin:0;min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:24px;background-color:#1a1a2e;font-family:Segoe UI,sans-serif;color:#fff}#datetime-picker{padding:10px 14px;border:2px solid #4e75ff;border-radius:8px;background:transparent;color:#fff;font-size:16px;outline:none;cursor:pointer}button[data-start]{padding:10px 24px;background:#4e75ff;color:#fff;border:none;border-radius:8px;font-size:16px;cursor:pointer;transition:opacity .2s}button[data-start]:disabled{opacity:.4;cursor:not-allowed}#datetime-picker:disabled{opacity:.4;cursor:not-allowed}.timer{display:flex;gap:16px}.field{display:flex;flex-direction:column;align-items:center;background:#16213e;border-radius:12px;padding:20px 28px;min-width:90px}.value{font-size:48px;font-weight:700;line-height:1;color:#4e75ff}.label{margin-top:8px;font-size:13px;text-transform:uppercase;letter-spacing:1px;color:#aaa}