@font-face {
    font-family: 'A2z';
    src: url('https://cdn.jsdelivr.net/gh/projectnoonnu/2601-6@1.0/에이투지체.woff') format('woff');
    font-weight: normal;
    font-style: normal;
}

body {
    background-color: #1a1a1a;
    color: #c5c5c5;
    font-family: 'A2z', sans-serif;
    font-size: 16px;
    margin: 0;
    padding: 0;
    background-image: linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px), linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
    background-size: 20px 20px;
}

h1 {
    text-align: center;
    color: #4d90fe;
    margin: 20px 0;
    font-size: 2.5em;
    text-shadow: 0 0 5px #4d90fe;
}

#menu {
    display: flex;
    justify-content: center;
    margin-top: 50px;
}

#menu ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
}

#menu li {
    margin: 0 15px;
}

#menu a {
    color: #c5c5c5;
    text-decoration: none;
    border: 1px solid #4d90fe;
    padding: 10px 20px;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
}

#menu a:hover {
    background-color: #4d90fe;
    color: #1a1a1a;
}

.calculator-section {
    background-color: #2a2a2a;
    border: 1px solid #4d90fe;
    border-radius: 8px;
    padding: 20px;
    margin: 30px auto;
    max-width: 800px;
    box-shadow: 0 0 15px rgba(77, 144, 254, 0.5);
}

.calculator-section h2 {
    color: #4d90fe;
    text-align: center;
    margin-bottom: 25px;
    font-size: 2em;
}

.measurement-row {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
    flex-wrap: wrap;
    justify-content: center;
}

.measurement-row input {
    background-color: #1a1a1a;
    border: 1px solid #666;
    color: #c5c5c5;
    padding: 10px;
    border-radius: 4px;
    flex: 1;
    min-width: 120px;
}

button {
    background-color: #007bff;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1em;
    margin: 5px;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #0056b3;
}

#density-results {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #333;
}

#density-results h3 {
    color: #4d90fe;
    margin-bottom: 10px;
}

#individual-results {
    list-style: decimal;
    margin-left: 20px;
    margin-bottom: 20px;
}

#individual-results li {
    margin-bottom: 5px;
}