body{margin:0;padding:0;background-color:#3f3f3f;font-size:16px;line-height:1.5}.container{max-width:800px;margin:0 auto;padding:20px;font-family:Arial,sans-serif}.header{text-align:center;margin-bottom:20px}.title{font-size:3em;color:#d6d5d5;margin:0}.subtitle{color:#fff;font-style:italic;font-size:2em;margin-top:0}.navbar{display:flex;justify-content:center;gap:10px;margin-bottom:20px}.nav-button{padding:10px 20px;border:none;background-color:#ebf0f5;color:#333;font-size:1em;cursor:pointer;transition:background-color .3s}.nav-button:hover{background-color:#040505}.nav-button.active{background-color:#007bff;color:#fff;font-weight:700}.conversion-area{border:1px solid #ddd;border-radius:8px}