:root {
    --primary-color: #4361ee;
    --secondary-color: #3f37c9;
    --accent-color: #4895ef;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --gray-color: #6c757d;
    --success-color: #4CAF50;
    --border-radius: 8px;
    --box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    --transition: all 0.3s ease;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    min-height: 100vh;
    color: var(--dark-color);
}

.container {
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 30px;
    margin: 30px;
    max-width: 1200px;
    width: 100%;
}

h1 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 30px;
    font-weight: 600;
    position: relative;
}

h1:after {
    content: "";
    display: block;
    width: 100px;
    height: 4px;
    background: var(--accent-color);
    margin: 10px auto 0;
    border-radius: 2px;
}

h3 {
    color: var(--primary-color);
    margin: 10px 0;
    font-weight: 500;
    text-align: center;
}

.upload-area {
    display: flex;
    justify-content: center;
    margin: 30px 0;
}

input[type="file"] {
    display: none;
}

.upload-area label {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    background-color: var(--primary-color);
    color: white;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 16px;
    transition: var(--transition);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.upload-area label:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.upload-area i {
    margin-right: 10px;
    font-size: 18px;
}

.image-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 30px;
    margin: 30px 0;
}

.canvas-wrapper {
    flex: 1;
    min-width: 300px;
    max-width: 600px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

canvas {
    width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    background-color: #f8f9fa;
    transition: var(--transition);
}

.controls {
    background-color: #f8f9fa;
    border-radius: var(--border-radius);
    padding: 20px;
    margin-top: 30px;
    box-shadow: var(--box-shadow);
}

.slider-container {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

.slider-container label {
    width: 100px;
    font-weight: 500;
    color: var(--gray-color);
}

input[type="range"] {
    flex: 1;
    -webkit-appearance: none;
    height: 8px;
    border-radius: 4px;
    background: #ddd;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    transition: var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
    background: var(--secondary-color);
    transform: scale(1.1);
}

.controls button {
    display: inline-block;
    margin: 15px 10px 0 0;
    padding: 12px 24px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 16px;
    transition: var(--transition);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.controls button:hover:not(:disabled) {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.controls button:disabled {
    background-color: var(--gray-color);
    cursor: not-allowed;
    opacity: 0.7;
}

.controls button i {
    margin-right: 8px;
}

.description {
    text-align: center;
    color: var(--gray-color);
    margin-bottom: 30px;
    font-size: 1.1em;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.6;
}

.features {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin: 20px 0;
    flex-wrap: wrap;
}

.feature-item {
    flex: 1;
    min-width: 140px;
    max-width: 160px;
    text-align: center;
    padding: 10px;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    transition: var(--transition);
}

.feature-item:hover {
    transform: translateY(-2px);
}

.feature-item i {
    font-size: 1.4em;
    color: var(--primary-color);
    margin-bottom: 8px;
}

.feature-item h3 {
    color: var(--dark-color);
    margin-bottom: 6px;
    font-size: 1em;
}

.feature-item p {
    color: var(--gray-color);
    font-size: 0.8em;
    margin: 0;
}

.donate-container {
    text-align: center;
    margin: 40px 0;
}

.donate-button {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 12px 25px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(50, 50, 93, 0.11), 0 1px 3px rgba(0, 0, 0, 0.08);
}

.donate-button:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 7px 14px rgba(50, 50, 93, 0.1), 0 3px 6px rgba(0, 0, 0, 0.08);
}

.donate-button i {
    margin-right: 8px;
    color: #ff6b6b;
}

footer {
    background-color: #f8f9fa;
    padding: 20px;
    margin-top: 30px;
    border-top: 1px solid #eee;
    color: var(--gray-color);
    text-align: center;
}

footer p {
    margin: 10px 0;
    font-size: 0.9em;
}

@media (max-width: 768px) {
    .image-container {
        flex-direction: column;
    }
    
    .controls {
        padding: 15px;
    }
    
    .slider-container {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .slider-container label {
        margin-bottom: 5px;
    }
    
    .controls button {
        width: 100%;
        margin: 10px 0 0 0;
    }
}