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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #0a0a0a;
    color: #ffffff;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

h1 {
    font-size: 3rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #ffffff 0%, #888888 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    text-align: center;
    font-size: 1.2rem;
    color: #888888;
    margin-bottom: 3rem;
    font-weight: 400;
}

.upload-area {
    position: relative;
    padding: 4rem 2rem;
    text-align: center;
    border: 2px dashed #333333;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.02);
    transition: all 0.3s ease;
    cursor: pointer;
    margin-bottom: 2rem;
}

.upload-area:hover {
    border-color: #555555;
    background: rgba(255, 255, 255, 0.05);
}

.upload-area.dragover {
    border-color: #ffffff;
    background: rgba(255, 255, 255, 0.1);
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.7;
}

.upload-text {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: #cccccc;
}

.upload-hint {
    font-size: 0.9rem;
    color: #888888;
}

#fileInput {
    position: absolute;
    left: -9999px;
    opacity: 0;
}

.file-info {
    display: none;
    margin-top: 1rem;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    border-left: 3px solid #ffffff;
}

.file-name {
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.file-size {
    color: #888888;
    font-size: 0.9rem;
}

.convert-btn {
    background: #ffffff;
    color: #000000;
    border: none;
    padding: 1rem 2rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    width: 100%;
    max-width: 300px;
    margin: 2rem auto 0;
    display: none;
}

.convert-btn:hover {
    background: #f0f0f0;
    transform: translateY(-2px);
}

.convert-btn:active {
    transform: translateY(0);
}

.convert-btn:disabled {
    background: #333333;
    color: #888888;
    cursor: not-allowed;
    transform: none;
}

.progress-bar {
    display: none;
    width: 100%;
    height: 4px;
    background: #333333;
    border-radius: 2px;
    overflow: hidden;
    margin-top: 1rem;
}

.progress-fill {
    height: 100%;
    background: #ffffff;
    width: 0%;
    transition: width 0.3s ease;
}

.status-message {
    text-align: center;
    margin-top: 1rem;
    padding: 1rem;
    border-radius: 8px;
    display: none;
}

.status-message.success {
    background: rgba(0, 255, 0, 0.1);
    color: #00ff00;
    border: 1px solid rgba(0, 255, 0, 0.3);
}

.status-message.error {
    background: rgba(255, 0, 0, 0.1);
    color: #ff6b6b;
    border: 1px solid rgba(255, 0, 0, 0.3);
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 4rem;
}

.feature {
    text-align: center;
    padding: 2rem 1rem;
}

.feature-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
    opacity: 0.8;
}

.feature-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.feature-description {
    color: #888888;
    font-size: 0.9rem;
}

.footer {
    text-align: center;
    padding: 2rem;
    color: #666666;
    font-size: 0.9rem;
    border-top: 1px solid #222222;
    margin-top: 4rem;
}

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

.footer-links {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.footer-links a {
    color: #888888;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #ffffff;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
}

.footer-logo {
    height: 16px;
    width: auto;
    opacity: 0.7;
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    h1 {
        font-size: 2.5rem;
    }

    .upload-area {
        padding: 3rem 1rem;
    }

    .features {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .footer-content {
        gap: 0.5rem;
    }

    .footer-links {
        font-size: 0.8rem;
    }

    .footer-brand {
        font-size: 0.7rem;
    }
}