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

:root {
    --primary-color: #2196F3;
    --secondary-color: #1976D2;
    --success-color: #4CAF50;
    --text-color: #333;
    --light-gray: #f5f5f5;
    --border-color: #ddd;
}

body {
    background-color: var(--light-gray);
    min-height: 100vh;
    line-height: 1.6;
    color: var(--text-color);
}

/* Header and Navigation */
header {
    background-color: white;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--primary-color);
}

/* Main Content */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

.hero {
    text-align: center;
    margin-bottom: 3rem;
}

.hero h2 {
    font-size: 2.5rem;
    color: var(--text-color);
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.2rem;
    color: #666;
}

/* Upload Section */
.upload-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.upload-box {
    background: white;
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.upload-box h2 {
    color: var(--text-color);
    margin-bottom: 1rem;
}

.upload-box p {
    color: #666;
    margin-bottom: 0.5rem;
}

.upload-box ul {
    list-style-position: inside;
    color: #666;
    margin-bottom: 1rem;
}

.drop-zone {
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 1rem;
}

.drop-zone:hover {
    border-color: var(--primary-color);
    background-color: #f8f9fa;
}

.drop-zone.dragover {
    border-color: var(--primary-color);
    background-color: #e3f2fd;
}

.upload-btn {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    margin-top: 1rem;
    transition: background-color 0.3s ease;
}

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

.preview {
    margin-top: 1rem;
    min-height: 100px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.preview img {
    max-width: 100%;
    max-height: 200px;
    border-radius: 4px;
}

/* Action Buttons */
.actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin: 2rem 0;
}

.actions button {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
}

#formatBtn {
    background-color: var(--success-color);
    color: white;
}

#formatBtn:hover:not(:disabled) {
    background-color: #388E3C;
}

#downloadBtn {
    background-color: var(--primary-color);
    color: white;
}

#downloadBtn:hover:not(:disabled) {
    background-color: var(--secondary-color);
}

button:disabled {
    background-color: #ccc !important;
    cursor: not-allowed;
}

/* Ad Container */
.ad-container {
    margin: 2rem 0;
    text-align: center;
    min-height: 100px;
    background: white;
    padding: 1rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* Info Sections */
.info-section {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    margin: 2rem 0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.info-section h2 {
    color: var(--text-color);
    margin-bottom: 1.5rem;
}

.info-section ol {
    padding-left: 1.5rem;
}

.info-section li {
    margin-bottom: 0.5rem;
}

.faq-item {
    margin-bottom: 1.5rem;
}

.faq-item h3 {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.faq-item p {
    color: #666;
}

/* Footer */
footer {
    background: white;
    padding: 2rem;
    margin-top: 3rem;
    box-shadow: 0 -2px 4px rgba(0, 0, 0, 0.1);
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

.footer-links a {
    color: var(--text-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: var(--primary-color);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-links {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }

    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }

    .hero h2 {
        font-size: 2rem;
    }
}