:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --secondary-hover: #475569;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-color: #1e293b;
    --border-color: #e2e8f0;
    --success-color: #16a34a;
    --error-color: #dc2626;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 500px;
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

header p {
    font-size: 0.875rem;
    color: #64748b;
}

.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

input[type="file"],
input[type="text"] {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.2s;
}

input[type="text"]:focus {
    outline: none;
    border-color: var(--primary-color);
}

button, .btn-download, .btn-print {
    display: block;
    width: 100%;
    padding: 0.75rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    text-align: center;
    text-decoration: none;
    transition: background-color 0.2s;
}

button:hover, .btn-print:hover {
    background-color: var(--primary-hover);
}

.btn-download {
    background-color: var(--secondary-color);
    margin-top: 0.75rem;
}

.btn-download:hover {
    background-color: var(--secondary-hover);
}

.button-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.hidden {
    display: none;
}

.status-box, .result-box, .error-box {
    margin-top: 2rem;
    padding: 1rem;
    border-radius: 6px;
    text-align: center;
}

.status-box {
    background-color: #eff6ff;
}

.result-box {
    background-color: #f0fdf4;
    border: 1px solid #bbf7d0;
}

.success-msg {
    color: var(--success-color);
    margin-bottom: 1rem;
    font-weight: 600;
}

.error-box {
    background-color: #fef2f2;
    border: 1px solid #fecaca;
    color: var(--error-color);
}

.loader {
    border: 3px solid #f3f3f3;
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    width: 24px;
    height: 24px;
    animation: spin 1s linear infinite;
    margin: 0 auto 0.5rem;
}

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

footer {
    margin-top: 2rem;
    text-align: center;
    font-size: 0.75rem;
    color: #94a3b8;
}

@media (max-width: 480px) {
    .container {
        padding: 1.5rem;
    }
}