:root{--primary-color:#4a90e2;--secondary-color:#f39c12;--background-color:#f5f6fa;--text-color:#2c3e50}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Arial,sans-serif;background-color:var(--background-color);color:var(--text-color)}.app{min-height:100vh;padding:2rem;max-width:800px;margin:0 auto}header{text-align:center;margin-bottom:2rem}header h1{font-size:2.5rem;color:var(--primary-color);text-shadow:2px 2px 4px rgba(0,0,0,.1)}.controls{background:#fff;padding:2rem;border-radius:12px;box-shadow:0 4px 6px rgba(0,0,0,.1);margin-bottom:2rem}.controls .input-group{margin-bottom:1rem}.controls .input-group label{display:block;margin-bottom:.5rem;font-weight:700}.controls .input-group input{width:100%;padding:.8rem;border:2px solid #e0e0e0;border-radius:6px;font-size:1rem;transition:border-color .3s ease}.controls .input-group input:focus{outline:none;border-color:var(--primary-color)}.draw-button{width:100%;padding:1rem;background-color:var(--primary-color);color:#fff;border:none;border-radius:6px;font-size:1.1rem;font-weight:600;cursor:pointer;transition:all .3s ease;box-shadow:0 2px 4px rgba(0,0,0,.1)}.draw-button:hover:not(:disabled){transform:translateY(-2px);background-color:#2275d7;box-shadow:0 4px 6px rgba(0,0,0,.2)}.draw-button:disabled{background-color:#ccc;cursor:not-allowed;opacity:.7}.result{text-align:center;margin:2rem 0}.result .number{font-size:4rem;font-weight:700;color:var(--secondary-color);text-shadow:2px 2px 4px rgba(0,0,0,.1)}.result .number.animate{animation:bounce .5s ease infinite}.history-section{margin-top:2rem;background:#fff;border-radius:10px;padding:1.5rem;box-shadow:0 4px 6px rgba(0,0,0,.1)}.history-section .history-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:1rem}.history-section .history-header h2{margin:0;color:var(--primary-color);font-size:1.5rem}.history{display:flex;flex-wrap:wrap;gap:.5rem;max-height:200px;overflow-y:auto;padding:.5rem}.history-number{display:inline-block;padding:.5rem 1rem;margin:.25rem;border-radius:.5rem;font-size:1.25rem;font-weight:600;color:#fff;background:linear-gradient(135deg,#1a5276,#154360);box-shadow:0 2px 4px rgba(0,0,0,.1);transition:all .3s ease;position:relative;overflow:hidden;opacity:var(--gradient-opacity,1)}.history-number.new-number{animation:slideIn .5s ease-out;box-shadow:0 4px 8px rgba(0,0,0,.2);opacity:1}.history-number:before{content:"";position:absolute;top:0;left:0;right:0;bottom:0;background:linear-gradient(135deg,hsla(0,0%,100%,.2),transparent);opacity:0;transition:opacity .3s ease}.history-number:hover:before{opacity:1}@keyframes slideIn{0%{transform:translateX(100%);opacity:0}to{transform:translateX(0);opacity:1}}.tips-container{margin-top:2rem;background:#fff;border-radius:10px;padding:1.5rem;box-shadow:0 4px 6px rgba(0,0,0,.1)}.tips-container h3{color:var(--primary-color);margin:0 0 1rem 0;font-size:1.2rem}.tips-container .tips-list{list-style:none;padding:0;margin:0}.tips-container .tips-list li{padding:.5rem 0;color:#666;position:relative;padding-left:1.5rem}.tips-container .tips-list li:before{content:"•";color:var(--primary-color);position:absolute;left:0;font-size:1.2rem}.tips-container .tips-list li:not(:last-child){border-bottom:1px solid #eee}.clear-button{background:#e74c3c;color:#fff;border:none;padding:.5rem 1rem;border-radius:.5rem;cursor:pointer;font-weight:600;transition:all .3s ease;box-shadow:0 2px 4px rgba(0,0,0,.1)}.clear-button:hover:not(:disabled){transform:translateY(-2px);background:#c0392b;box-shadow:0 4px 6px rgba(0,0,0,.2)}.clear-button:disabled{background:#ccc;cursor:not-allowed;opacity:.7}.button-text{display:inline-block;padding:.2rem .5rem;border-radius:4px;font-weight:600;font-size:.9em;margin:0 .2rem}.button-text.draw{background-color:var(--primary-color)}.button-text.clear,.button-text.draw{color:#fff;box-shadow:0 2px 4px rgba(0,0,0,.1)}.button-text.clear{background-color:#e74c3c}