:root{--primary:#2c3e50;--accent:#2980b9;--bg:#f4f7f6}body{font-family:"Helvetica Neue",Arial,sans-serif;background-color:var(--bg);padding:20px;color:#333;line-height:1.6}.container{max-width:800px;margin:0 auto;background:#fff;padding:30px;border-radius:15px;box-shadow:0 5px 15px rgba(0,0,0,.08)}h1{text-align:center;color:var(--primary);font-size:1.6rem;border-bottom:2px solid var(--primary);padding-bottom:15px;margin-bottom:30px}.form-section{border:1px solid #eee;padding:20px;border-radius:10px;margin-bottom:20px;background:#fafafa}.section-title{font-weight:700;color:var(--primary);margin-bottom:15px;display:block;border-left:4px solid var(--primary);padding-left:10px}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px}.form-group{display:flex;flex-direction:column}label{font-size:.85rem;font-weight:700;margin-bottom:5px;color:#555}input,select{padding:12px;border:1px solid #ccc;border-radius:8px;font-size:1rem}.calc-btn{width:100%;padding:18px;background:var(--primary);color:#fff;border:none;border-radius:8px;font-size:1.2rem;font-weight:700;cursor:pointer;margin-top:10px;transition:.3s}.calc-btn:hover{background:#34495e;transform:translateY(-1px)}.result-box{margin-top:30px;display:none;background:#fff;border:2px solid var(--primary);border-radius:10px;overflow:hidden}.result-header{background:var(--primary);color:#fff;padding:12px;text-align:center;font-weight:700}.result-body{padding:25px;text-align:center}.amount-display{font-size:2.2rem;font-weight:700;color:#e67e22;margin:10px 0}.amount-display span{font-size:1rem;color:#333;margin-left:5px}.note{font-size:.8rem;color:#777;background:#fff;padding:15px;margin-top:20px;border-radius:8px;border:1px solid #ddd}@media screen and (max-width:600px){.container{padding:20px}.form-grid{grid-template-columns:1fr}h1{font-size:1.3rem}.amount-display{font-size:1.8rem}}