:root{--bg-primary: #1a1a1a;--bg-secondary: #2d2d2d;--text-primary: #ffffff;--text-secondary: #a0a0a0;--accent: #4a9eff;--accent-hover: #3a8eef;--error: #ff6b6b;--success: #4ade80;--warning: #fbbf24;--border: #3d3d3d;--workout-color: #4a9eff;--rest-color: #4ade80;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;line-height:1.5;font-weight:400;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}@media(prefers-color-scheme:light){:root{--bg-primary: #ffffff;--bg-secondary: #f0f0f0;--text-primary: #1a1a1a;--text-secondary: #666666;--border: #e0e0e0}}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--bg-primary);color:var(--text-primary);min-width:320px;min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:1rem}#root{width:100%;max-width:600px;display:flex;flex-direction:column;align-items:center;gap:2rem}input{font-family:inherit;font-size:1rem;padding:.75rem;border:1px solid var(--border);border-radius:8px;background-color:var(--bg-primary);color:var(--text-primary);transition:border-color .2s}input:focus{outline:none;border-color:var(--accent)}label{font-size:.875rem;font-weight:500;color:var(--text-secondary);margin-bottom:.5rem;display:block}button{font-family:inherit;font-size:1rem;font-weight:600;padding:1rem 2rem;border:none;border-radius:8px;cursor:pointer;transition:all .2s;min-height:44px;min-width:44px}button:active{transform:scale(.98)}.btn-primary{background-color:var(--accent);color:#fff}.btn-primary:hover{background-color:var(--accent-hover)}.btn-secondary{background-color:var(--bg-secondary);color:var(--text-primary)}.btn-secondary:hover{background-color:var(--border)}.error{color:var(--error);font-size:.75rem;margin-top:.25rem;display:block}.timer-display{text-align:center;padding:2rem;border-radius:16px;background-color:var(--bg-secondary);transition:all .3s ease}.timer-display.fullscreen{position:fixed;inset:0;display:flex;flex-direction:column;justify-content:center;align-items:center;z-index:1000;border-radius:0;background-color:var(--bg-primary)}.timer-display.fullscreen.workout{background:linear-gradient(135deg,#1a1a1a,#1e3a5f)}.timer-display.fullscreen.rest{background:linear-gradient(135deg,#1a1a1a,#1e4d2f)}.timer-display.fullscreen .timer-time{font-size:12rem}.timer-display.fullscreen.workout .timer-time{color:var(--workout-color)}.timer-display.fullscreen.rest .timer-time{color:var(--rest-color)}.timer-display.fullscreen .timer-label{font-size:2rem}.timer-time{font-size:6rem;font-weight:700;line-height:1;margin-bottom:.5rem;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.timer-label{font-size:1.125rem;color:var(--text-secondary);font-weight:500}.timer-display.warning{animation:flicker .5s infinite;border:2px solid var(--warning)}@keyframes flicker{0%,to{opacity:1}50%{opacity:.7}}@media(max-width:640px){.timer-time{font-size:4rem}.timer-display.fullscreen .timer-time{font-size:8rem}.timer-display.fullscreen .timer-label{font-size:1.5rem}}.controls{display:flex;gap:1rem;width:100%;justify-content:center}.controls.fullscreen{position:fixed;bottom:2rem;left:0;right:0;z-index:1001;padding:0 2rem}.settings{display:flex;flex-direction:column;gap:1.5rem;width:100%;padding:1.5rem;border-radius:12px;background-color:var(--bg-secondary)}.setting-group{display:flex;flex-direction:column;gap:.5rem}.setting-group input{width:100%}@media(min-width:640px){.settings{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem}.setting-group{grid-column:span 1}}.footer{margin-top:2rem;padding:1rem;text-align:center;color:var(--text-secondary);font-size:.875rem}.footer p{margin:0}.footer a{color:var(--accent);text-decoration:none;transition:color .2s}.footer a:hover{color:var(--accent-hover);text-decoration:underline}.footer .heart{color:var(--error);display:inline-block;animation:heartbeat 1.5s infinite}@keyframes heartbeat{0%,to{transform:scale(1)}10%,30%{transform:scale(1.1)}20%,40%{transform:scale(1)}}