:root{--color-work: #e74c3c;--color-break: #27ae60;--color-start: #3498db;--color-pause: #e67e22;--color-reset: #7f8c8d;--color-text: #1c1c1e;--color-text-secondary: #6e6e73;--color-bg: #fafafa}@media (prefers-color-scheme: dark){:root{--color-text: #f2f2f7;--color-text-secondary: #98989d;--color-bg: #000}}*{box-sizing:border-box}html,body{margin:0;padding:0;height:100%;font-family:-apple-system,BlinkMacSystemFont,Helvetica Neue,Segoe UI,sans-serif;background:var(--color-bg);color:var(--color-text);-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent}.app{min-height:100dvh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2.5rem;padding:1.5rem;padding-top:max(1.5rem,env(safe-area-inset-top));padding-bottom:max(1.5rem,env(safe-area-inset-bottom));text-align:center}.session-label{font-size:1.75rem;font-weight:600;margin:0;transition:color .2s ease}.session-label.work{color:var(--color-work)}.session-label.break{color:var(--color-break)}.time-display{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:clamp(4.5rem,18vw,7rem);font-weight:700;letter-spacing:-.02em;font-variant-numeric:tabular-nums;line-height:1}.iteration-label{margin:0;font-size:1.05rem;color:var(--color-text-secondary)}.controls{display:flex;gap:1.25rem;flex-wrap:wrap;justify-content:center}.btn{-webkit-appearance:none;-moz-appearance:none;appearance:none;border:none;border-radius:12px;font-size:1.15rem;font-weight:600;color:#fff;width:130px;height:54px;cursor:pointer;transition:transform .08s ease,opacity .2s ease}.btn:active{transform:scale(.96)}.btn-start{background:var(--color-start)}.btn-pause{background:var(--color-pause)}.btn-reset{background:var(--color-reset)}