body {
    font-family: 'Helvetica', Arial, sans-serif;
    background-color: #fff;
    color: #000;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    max-width: 900px;
    width: 100%;
    margin: 20px;
    background-color: #fff;
    border: 2px solid #000;
    box-shadow: 8px 8px 0 #000;
}

header {
    text-align: center;
    padding: 20px;
    border-bottom: 2px solid #000;
}

h1 {
    margin: 0;
    font-size: 2.5em;
    font-weight: bold;
}

.input-form {
    padding: 30px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.input-group {
    display: flex;
    flex-direction: column;
}

label {
    font-size: 1.1em;
    font-weight: bold;
    margin-bottom: 8px;
}

input {
    padding: 12px;
    font-size: 1em;
    border: 2px solid #000;
    background-color: #fff;
    color: #000;
    transition: border-color 0.3s;
}

input:focus {
    outline: none;
    border-color: #666;
}

.submit-btn {
    padding: 15px;
    font-size: 1.2em;
    font-weight: bold;
    background-color: #000;
    color: #fff;
    border: none;
    cursor: pointer;
    transition: background-color 0.3s;
}

.submit-btn:hover {
    background-color: #333;
}

.loading {
    text-align: center;
    padding: 20px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #000;
    border-top: 4px solid transparent;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 10px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.output {
    margin: 30px;
    padding: 20px;
    border: 2px solid #000;
    background-color: #fff;
    font-size: 1em;
    line-height: 1.6;
}

.output h2 {
    font-size: 1.8em;
    font-weight: bold;
    border-bottom: 2px solid #000;
    padding-bottom: 5px;
    margin-bottom: 15px;
}

.output h3 {
    font-size: 1.4em;
    font-weight: bold;
    margin-top: 20px;
}

.output h4 {
    font-size: 1.2em;
    font-weight: bold;
    background-color: #000;
    color: #fff;
    padding: 8px;
    margin: 15px 0 10px;
}

.output p {
    margin: 10px 0;
}

.output ul {
    list-style-type: disc;
    margin-left: 20px;
    margin-bottom: 15px;
}

.output li {
    margin-bottom: 8px;
}

.download-btn {
    display: block;
    margin: 20px auto;
    padding: 15px 30px;
    font-size: 1.1em;
    font-weight: bold;
    background-color: #000;
    color: #fff;
    border: none;
    cursor: pointer;
    transition: background-color 0.3s;
}

.download-btn:hover {
    background-color: #333;
}