.header-section {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 30px;
    flex-wrap: wrap;
    gap: 15px;
}

.back-btn {
    background: linear-gradient(135deg, #6c757d 0%, #5a6268 100%);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 10px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(108, 117, 125, 0.3);
}

.back-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(108, 117, 125, 0.4);
}

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

.back-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.header-section h1 {
    color: #2c3e50;
    margin: 0;
    font-size: 28px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.header-section h1 i {
    color: #667eea;
}

.logo-section {
    background: white;
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.section-header {
    margin-bottom: 25px;
}

.section-header h2 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 22px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-header h2 i {
    color: #667eea;
}

.section-description {
    color: #6c757d;
    font-size: 14px;
    margin: 0;
}

.upload-area {
    border: 2px dashed #dee2e6;
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    background: #f8f9fa;
    transition: all 0.3s ease;
}

.upload-area:hover {
    border-color: #667eea;
    background: #f0f4ff;
}

.upload-preview {
    margin-bottom: 20px;
    min-height: 150px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    background: white;
    padding: 20px;
}

.upload-preview img {
    max-width: 100%;
    max-height: 200px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.upload-preview i {
    font-size: 48px;
    color: #9ca3af;
    margin-bottom: 15px;
}

.upload-preview p {
    color: #6c757d;
    margin: 0;
    font-size: 14px;
}

.upload-controls {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
}

.upload-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.upload-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

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

.upload-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.2);
}

.remove-btn {
    background: #dc3545;
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.remove-btn:hover {
    background: #c82333;
    transform: translateY(-2px);
}

.remove-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.remove-btn.hidden {
    display: none;
}

.upload-progress {
    margin-top: 25px;
    padding: 25px;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border-radius: 12px;
    border: 2px solid #e9ecef;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.upload-progress.hidden {
    display: none;
}

.progress-bar {
    width: 100%;
    height: 16px;
    background: #e9ecef;
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 15px;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    border-radius: 10px;
    transition: width 0.3s ease;
    width: 0%;
    position: relative;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255, 255, 255, 0.3),
        transparent
    );
    animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

.progress-text {
    display: block;
    text-align: center;
    color: #2c3e50;
    font-size: 16px;
    font-weight: 600;
}

.result-message {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    padding: 15px 25px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 10000;
    display: none;
    font-weight: 500;
    min-width: 300px;
    text-align: center;
}

.result-message.success {
    background: #28a745;
    color: white;
}

.result-message.error {
    background: #dc3545;
    color: white;
}

.result-message a {
    color: white;
    text-decoration: underline;
}