.containerxb {
    width: 100%;
    max-width: 1000px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    justify-content: center;
    overflow: hidden;
    margin: 0 auto;
    text-align: center;
}

header {
    background: #ff0000;
    color: white;
    padding: 20px;
    text-align: center;
}

header h1 {
    font-size: 28px;
    margin-bottom: 5px;
}

header p {
    opacity: 0.9;
    font-size: 16px;
}

.main-content {
    padding: 30px;
    text-align: center;
}

.input-section {
    margin-bottom: 30px;
    text-align: center;
}

.url-input {
    width: 100%;
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 16px;
    transition: all 0.3s;
    text-align: center;
}

.url-input:focus {
    border-color: #ff0000;
    outline: none;
    box-shadow: 0 0 0 3px rgba(255, 0, 0, 0.1);
}

.btnthum {
    background: #ff0000;
    color: white;
    border: none;
    padding: 15px 25px;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btnthum:hover {
    background: #cc0000;
    transform: translateY(-2px);
}

.btnthum:active {
    transform: translateY(0);
}

.btnthum i {
    margin-right: 8px;
}

.extract-btnthum {
    width: 100%;
    margin-top: 15px;
}

.thumbnail-section {
    display: none;
    margin-top: 30px;
    text-align: center;
}

.thumbnail-section.active {
    display: block;
}

.thumbnail-preview {
    max-width: 100%;
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    margin-bottom: 20px;
}

.quality-options {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    margin-bottom: 20px;
}

.quality-btnthum {
    background: #f0f0f0;
    border: 2px solid #e0e0e0;
    padding: 10px 15px;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.quality-btnthum:hover {
    background: #e0e0e0;
}

.quality-btnthum.active {
    background: #ff0000;
    color: white;
    border-color: #ff0000;
}

.download-btnthum {
    margin-top: 10px;
}

.instructions {
    background: #f9f9f9;
    padding: 20px;
    border-radius: 8px;
    margin-top: 30px;
    text-align: center;
}

.instructions h3 {
    color: #ff0000;
    margin-bottom: 10px;
}

.instructions ol {
    padding-left: 20px;
    text-align: left;
    display: inline-block;
}

.instructions li {
    margin-bottom: 8px;
    line-height: 1.5;
}

.loading {
    display: none;
    text-align: center;
    margin: 20px 0;
}

.loading.active {
    display: block;
}

.spinner {
    border: 4px solid rgba(0, 0, 0, 0.1);
    border-left-color: #ff0000;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

@media (max-width: 600px) {
    .containerxb {
        border-radius: 10px;
    }
    
    .main-content {
        padding: 20px;
    }
    
    header h1 {
        font-size: 24px;
    }
    
    .quality-options {
        flex-direction: column;
        align-items: center;
    }
    
    .quality-btnthum {
        width: 100%;
        text-align: center;
    }
}