.irr-calculator{font-family:Arial,sans-serif;max-width:500px;margin:0 auto;padding:20px;border:1px solid #ddd;border-radius:5px;box-shadow:0 2px 4px #0000001a;background-color:#f9f9f9}.irr-calculator h2{text-align:center;color:#333}.irr-calculator form{display:flex;flex-direction:column;gap:15px}.irr-calculator label{font-weight:700;color:#555}.irr-calculator input{padding:10px;border:1px solid #ccc;border-radius:4px;font-size:16px}.irr-calculator button{padding:10px;background-color:#007bff;color:#fff;border:none;border-radius:4px;cursor:pointer;font-size:16px;transition:background-color .3s}.irr-calculator button:hover{background-color:#0056b3}.irr-calculator .result,.irr-calculator .error{padding:15px;border-radius:4px;text-align:center;font-size:18px}.irr-calculator .result{background-color:#e2f5e2;border:1px solid #b2d8b2;color:#2d6a2d}.irr-calculator .error{background-color:#f8d7da;border:1px solid #f5c2c7;color:#842029}.irr-footer{text-align:center;margin-top:20px;padding-top:10px;border-top:1px solid #ddd}.irr-footer p{font-size:14px;color:#666}:root{--primary-color: #3498db;--secondary-color: #2ecc71;--accent-color: #e74c3c;--light-gray: #f9f9f9;--dark-gray: #333;--text-color: #555}body{font-family:Arial,sans-serif;line-height:1.6;color:var(--text-color);margin:0;padding:0;text-align:center}h2{color:var(--primary-color)}section{padding:20px;margin:20px;border-radius:5px;background-color:var(--light-gray)}ol,ul{padding-left:20px;text-align:left}.introduction{border:2px solid var(--secondary-color)}.how-to-use{background-color:var(--primary-color);color:#fff;border:2px solid var(--accent-color)}.benefits{background-color:var(--secondary-color);color:#fff}.main-page-container{display:flex;justify-content:center;align-items:flex-start;min-height:100vh}.sidebar-design{flex:1;background:linear-gradient(135deg,var(--primary-color),var(--secondary-color));clip-path:polygon(0 0,100% 0,80% 100%,0% 100%)}.main-page{flex:3;max-width:800px;padding:20px;text-align:center;background:white;border-radius:10px;box-shadow:0 2px 10px #0000001a;margin:30px}.sidebar-design.right{background:linear-gradient(135deg,var(--secondary-color),var(--accent-color));clip-path:polygon(20% 0,100% 0,100% 100%,0% 100%)}