* {
    box-sizing: border-box;
}

body {
    margin: 0;

    font-family:
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        "Noto Sans JP",
        sans-serif;

    background: #f4f6f8;
    color: #222;
}

.container {
    min-height: 100vh;

    display: flex;
    justify-content: center;
    align-items: center;

    padding: 24px;
}

.card {
    width: 100%;
    max-width: 640px;

    background: #ffffff;

    border-radius: 16px;

    padding: 40px;

    box-shadow:
        0 8px 30px
        rgba(0, 0, 0, 0.08);
}

h1 {
    margin-top: 0;
    margin-bottom: 12px;

    font-size: 28px;
}

.description {
    color: #666;
    margin-bottom: 32px;
}

.upload-area {
    margin-bottom: 24px;
}

.upload-area label {
    display: block;

    margin-bottom: 8px;

    font-weight: bold;
}

input[type="file"] {
    width: 100%;

    padding: 16px;

    border: 2px dashed #c8cdd3;
    border-radius: 10px;

    background: #fafafa;
}

button {
    width: 100%;

    padding: 14px 20px;

    border: none;
    border-radius: 10px;

    background: #222;
    color: white;

    font-size: 16px;
    font-weight: bold;

    cursor: pointer;
}

button:hover {
    opacity: 0.88;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.status {
    margin-top: 20px;

    text-align: center;

    min-height: 24px;
}

.result {
    margin-top: 28px;

    padding-top: 24px;

    border-top: 1px solid #ddd;
}

.result h2 {
    font-size: 20px;
    margin-top: 0;
}

.download-buttons {
    display: flex;
    gap: 12px;
}

.download-button {
    flex: 1;

    display: block;

    padding: 13px;

    text-decoration: none;
    text-align: center;

    border-radius: 8px;

    background: #e9eef5;
    color: #222;

    font-weight: bold;
}

.download-button:hover {
    background: #dde5ef;
}

.hidden {
    display: none;
}

.error {
    color: #c62828;
}

.success {
    color: #2e7d32;
}

@media (max-width: 600px) {

    .card {
        padding: 24px;
    }

    .download-buttons {
        flex-direction: column;
    }
}