:root{--primary-color:#3498db;--primary-dark:#2980b9;--text-color:#2c3e50;--text-light:#7f8c8d;--bg-color:#f0f2f5;--card-bg:#fff;--border-color:#ddd;--error-color:#e74c3c;--success-color:#2ecc71;--warning-color:#f39c12;--shadow:0 2px 15px rgba(0,0,0,.1);--shadow-lg:0 8px 30px rgba(0,0,0,.12);--transition:all 0.3s ease;--border-radius:12px}@media (prefers-color-scheme:dark){:root{--text-color:#ecf0f1;--text-light:#bdc3c7;--bg-color:#2c3e50;--card-bg:#34495e;--border-color:#4a6278}}*{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;line-height:1.6;background-color:var(--bg-color);color:var(--text-color);transition:var(--transition);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}.container{max-width:1200px;margin:0 auto;padding:20px}.card{background:var(--card-bg);border-radius:var(--border-radius);box-shadow:var(--shadow);transition:var(--transition);overflow:hidden}.card:hover{box-shadow:var(--shadow-lg)}.btn{padding:12px 24px;border:none;border-radius:8px;font-size:1em;font-weight:500;cursor:pointer;transition:var(--transition);text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:8px}.btn-primary{background-color:var(--primary-color);color:#fff}.btn-primary:hover{background-color:var(--primary-dark);transform:translateY(-2px)}.btn-secondary{background-color:transparent;color:var(--text-color);border:2px solid var(--border-color)}.btn-secondary:hover{border-color:var(--primary-color);color:var(--primary-color)}.input-group{margin-bottom:20px;position:relative}.label{display:block;margin-bottom:8px;font-size:.95em;font-weight:500}.input,.label{color:var(--text-color)}.input{width:100%;padding:12px 16px;border:2px solid var(--border-color);border-radius:8px;font-size:1em;background-color:var(--card-bg);transition:var(--transition);-webkit-appearance:none;-moz-appearance:none;appearance:none}.input:focus{outline:none;border-color:var(--primary-color);box-shadow:0 0 0 3px rgba(52,152,219,.2)}.input.error{border-color:var(--error-color)}.hint{color:var(--text-light)}.error-text,.hint{font-size:.85em;margin-top:4px}.error-text{color:var(--error-color)}.result{margin-top:20px;padding:20px;background-color:rgba(52,152,219,.1);border-radius:8px;font-size:1.1em;color:var(--text-color);font-weight:500;text-align:center;transition:var(--transition)}.grid{display:grid;grid-gap:24px;gap:24px}.grid-2{grid-template-columns:repeat(auto-fit,minmax(300px,1fr))}.grid-3{grid-template-columns:repeat(auto-fit,minmax(250px,1fr))}.tabs{display:flex;border-bottom:2px solid var(--border-color);margin-bottom:24px;flex-wrap:wrap}.tab{padding:12px 24px;background:none;color:var(--text-light);cursor:pointer;transition:var(--transition);font-size:1em;border:none;border-bottom:2px solid transparent;margin-bottom:-2px}.tab.active{border-bottom-color:var(--primary-color)}.tab.active,.tab:hover{color:var(--primary-color)}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.fade-in{animation:fadeIn .5s ease-out}.loading{position:relative;pointer-events:none}.loading:after{content:"";position:absolute;top:50%;left:50%;width:20px;height:20px;margin:-10px 0 0 -10px;border:2px solid var(--primary-color);border-top:2px solid transparent;border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(1turn)}}@media (max-width:768px){.container{padding:16px}.grid-2,.grid-3{grid-template-columns:1fr}.tabs{overflow-x:auto;white-space:nowrap}.tab{padding:12px 16px;font-size:.9em}.btn{padding:14px 20px;width:100%}}@media (hover:none) and (pointer:coarse){.btn{min-height:44px;min-width:44px}.input{font-size:16px}}