* {box-sizing: border-box;}
body {font-family: "Segoe UI",Tahoma,Geneva,Verdana,sans-serif;display: flex;justify-content: center;align-items: center;min-height: 100vh;background: #f8f9fa;margin: 0;}
.bmi-container {background: #f8f9fa;padding: 2rem;border-radius: 1rem;box-shadow: 0 0 15px rgba(0,0,0,.1);width: 100%;max-width: 400px;}
.bmi-container h2 {text-align: center;margin-bottom: 1rem;color: #07c;}
.input-group {margin-bottom: 1rem;}
.input-group label {display: block;margin-bottom: .5rem;font-weight: bold;}
.input-group input {width: 100%;padding: .6rem;border: 1px solid #ccc;border-radius: .5rem;}
.calculate-btn {width: 100%;padding: .7rem;background: #07c;color: white;border: none;border-radius: .5rem;font-size: 1rem;cursor: pointer;margin-top: 1rem;}
.calculate-btn:hover {background: #005fa3;}
.result {margin-top: 1.5rem;text-align: center;}
.result h3 {margin: .5rem 0;}
.category {font-weight: bold;color: #07c;}