:root {
    --primary-gradient: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
    --secondary-gradient: linear-gradient(to right, #4b6cb7, #182848);
    --success-gradient: linear-gradient(to right, #00b09b, #96c93d);
}

body {
    /*background: var(--primary-gradient);*/
    min-height: 100vh;
    /*padding: 20px;*/
    /*font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;*/
    color: #333;
}

.app-container {
    max-width: 1200px;
    margin: 0 auto;
}

.card {
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.25);
    overflow: hidden;
    border: none;
    margin-bottom: 25px;
    background: rgba(255, 255, 255, 0.95);
}

.card-header {
    background: var(--secondary-gradient);
    color: white;
    font-weight: 700;
    padding: 18px 25px;
    font-size: 1.4rem;
}

.upload-area {
    background-color: rgba(75, 108, 183, 0.08);
    border: 3px dashed #4b6cb7;
    border-radius: 15px;
    padding: 45px 25px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    min-height: 300px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.upload-area:hover, .upload-area.dragover {
    background-color: rgba(75, 108, 183, 0.15);
    border-color: #3a56a0;
    transform: translateY(-3px);
}

.upload-icon {
    font-size: 70px;
    color: #4b6cb7;
    margin-bottom: 20px;
}

.preview-container {
    background-color: rgba(75, 108, 183, 0.08);
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    margin-top: 25px;
}

.preview-title {
    font-weight: 600;
    color: #4b6cb7;
    margin-bottom: 15px;
    font-size: 1.2rem;
}

.preview-image {
    max-width: 100%;
    max-height: 280px;
    border-radius: 10px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
    border: 1px solid #e0e0e0;
}

.file-info {
    background-color: rgba(75, 108, 183, 0.1);
    border-radius: 10px;
    padding: 12px 18px;
    margin-top: 18px;
    font-size: 0.95rem;
    color: #4a5568;
}

.control-panel {
    background-color: rgba(75, 108, 183, 0.08);
    border-radius: 15px;
    padding: 25px;
    margin-top: 25px;
}

.control-title {
    font-weight: 700;
    color: #4b6cb7;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.25rem;
    position: relative;
}

.control-title:after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--secondary-gradient);
    border-radius: 3px;
}

.slider-container {
    margin-bottom: 30px;
}

.slider-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
}

.slider-label {
    font-weight: 600;
    color: #4a5568;
}

.slider-value {
    font-weight: 700;
    color: #4b6cb7;
    background: rgba(75, 108, 183, 0.1);
    padding: 2px 12px;
    border-radius: 20px;
    min-width: 60px;
    text-align: center;
}

.form-range {
    height: 8px;
    border-radius: 4px;
}

.form-range::-webkit-slider-thumb {
    width: 22px;
    height: 22px;
    background: var(--secondary-gradient);
}

.form-range::-moz-range-thumb {
    width: 22px;
    height: 22px;
    background: var(--secondary-gradient);
    border: none;
}

.btn-compress {
    background: var(--secondary-gradient);
    border: none;
    padding: 14px 30px;
    font-weight: 700;
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
    width: 100%;
    font-size: 1.1rem;
    border-radius: 12px;
    margin-top: 10px;
    box-shadow: 0 4px 15px rgba(75, 108, 183, 0.4);
}

.btn-compress:hover {
    transform: translateY(-3px);
    box-shadow: 0 7px 20px rgba(75, 108, 183, 0.5);
}

.btn-compress:active {
    transform: translateY(1px);
}

.btn-compress:disabled {
    opacity: 0.7;
    transform: none;
    box-shadow: none;
}

.progress-container {
    background-color: rgba(75, 108, 183, 0.1);
    border-radius: 12px;
    padding: 25px;
    margin-top: 25px;
}

.result-container {
    background-color: rgba(0, 176, 155, 0.08);
    border-radius: 15px;
    padding: 25px;
    /*margin-top: 25px;*/
}

.result-header {
    font-weight: 700;
    color: #00b09b;
    margin-bottom: 20px;
    text-align: center;
    font-size: 1.25rem;
}

.comparison-container {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 25px;
}

.image-box {
    flex: 1;
    min-width: 280px;
    padding: 15px;
    text-align: center;
}

.image-title {
    background: var(--secondary-gradient);
    color: white;
    padding: 10px 20px;
    border-radius: 30px;
    font-weight: 600;
    margin-bottom: 15px;
    display: inline-block;
    font-size: 1.1rem;
}

.image-box:nth-child(2) .image-title {
    background: var(--success-gradient);
}

.savings-badge {
    background: var(--success-gradient);
    padding: 12px 25px;
    border-radius: 30px;
    font-weight: 700;
    margin: 25px auto;
    color: white;
    font-size: 1.1rem;
    display: inline-block;
    box-shadow: 0 4px 15px rgba(0, 176, 155, 0.4);
}

.btn-download {
    background: var(--success-gradient);
    border: none;
    padding: 14px 30px;
    font-weight: 700;
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
    width: 100%;
    max-width: 350px;
    font-size: 1.1rem;
    border-radius: 12px;
    margin: 20px auto 0;
    display: block;
    box-shadow: 0 4px 15px rgba(0, 176, 155, 0.4);
    color: white;
}

.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: 0 7px 20px rgba(0, 176, 155, 0.5);
    color: white;
}

.empty-result {
    text-align: center;
    padding: 40px 20px;
    color: #718096;
}

.empty-icon {
    font-size: 80px;
    color: #cbd5e0;
    margin-bottom: 20px;
}

.footer {
    color: rgba(255, 255, 255, 0.85);
    text-align: center;
    padding: 25px;
    font-size: 0.95rem;
}

.feature-list {
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
    margin: 20px 0;
}

.feature-item {
    display: flex;
    align-items: center;
    margin: 10px;
    background: rgba(255, 255, 255, 0.15);
    padding: 10px 20px;
    border-radius: 50px;
    color: white;
}

.feature-icon {
    font-size: 1.2rem;
    margin-right: 8px;
}
.tech-section {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 30px;
    margin: 40px 0;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.section-title {
    font-weight: 800;
    color: #4b6cb7;
    margin-bottom: 25px;
    text-align: center;
    font-size: 1.8rem;
    position: relative;
    padding-bottom: 15px;
}

.section-title:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: var(--secondary-gradient);
    border-radius: 4px;
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.tech-card {
    background: white;
    border-radius: 15px;
    padding: 25px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    border: 1px solid #eee;
    transition: all 0.3s ease;
}

.tech-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.tech-title {
    font-weight: 700;
    color: #4b6cb7;
    margin-bottom: 15px;
    font-size: 1.3rem;
    display: flex;
    align-items: center;
}

.tech-title i {
    margin-right: 10px;
    font-size: 1.5rem;
}

.tech-desc {
    color: #4a5568;
    line-height: 1.6;
}

.highlight {
    background: linear-gradient(120deg, #a2d2ff, #bde0fe);
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 600;
}
@media (max-width: 768px) {
    .upload-area {
        padding: 30px 15px;
        min-height: 250px;
    }

    .upload-icon {
        font-size: 50px;
    }

    .card-header {
        font-size: 1.2rem;
        padding: 15px 20px;
    }

    .control-panel, .result-container {
        padding: 20px 15px;
    }
    .tech-grid {
                grid-template-columns: 1fr;
            }
}