* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: #f0f2f5;
    padding: 20px;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

h1 {
    color: #1a73e8;
    margin-bottom: 20px;
    text-align: center;
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 5px;
    color: #333;
    font-weight: 500;
}

select, input {
    width: 100%;
    padding: 10px;
    margin-bottom: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
}

.shape-inputs {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 15px;
}

.dimension-group {
    display: flex;
    gap: 10px;
}

.dimension-group input {
    width: 50%;
}

button {
    background: #1a73e8;
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    width: 100%;
    font-size: 16px;
    transition: background 0.3s;
    margin: 5px 0;
}

button:hover {
    background: #1557b0;
}

#downloadBtn {
    background: #28a745;
    display: none;
}

#downloadBtn:hover {
    background: #218838;
}

#results {
    margin-top: 20px;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 5px;
    display: none;
}

.footer {
    margin-top: 20px;
    text-align: center;
    color: #666;
    font-size: 14px;
    padding-top: 15px;
    border-top: 1px solid #eee;
}