:root {
    --primary-color: #28A0FF;
    --secondary-color: #6C5CE7;
    --background-dark: #0A0A19;
    --card-background: #1A1A2E;
    --text-primary: #FFFFFF;
    --text-secondary: #B4B4C8;
    --success-color: #00D9A3;
    --error-color: #FF5C5C;
    --border-radius: 12px;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-dark);
    color: var(--text-primary);
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.site-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    padding: 30px 0;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.site-title {
    margin: 0;
    font-size: 3rem;
    font-weight: 700;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
    color: var(--text-primary);
}

.site-subtitle {
    margin: 10px 0 0 0;
    font-size: 1.2rem;
    color: rgba(255,255,255,0.9);
    font-weight: 300;
}

main {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px 10px;
    max-width: 400px;
    margin: 0 auto;
}

.app-container {
    width: 100%;
    max-width: 350px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.site-footer {
    background-color: var(--card-background);
    padding: 20px 0;
    text-align: center;
    border-top: 1px solid var(--secondary-color);
    margin-top: auto;
}

.site-footer p {
    margin: 5px 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

h1 {
    color: var(--primary-color);
    margin-bottom: 30px;
    font-size: 2.5rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

#fileInput {
    margin-bottom: 20px;
    padding: 10px;
    background-color: var(--card-background);
    color: var(--text-primary);
    border: 2px dashed var(--secondary-color);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s ease;
}

#fileInput:hover {
    border-color: var(--primary-color);
    background-color: rgba(40, 160, 255, 0.1);
}

#controls {
    background-color: var(--card-background);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    margin-bottom: 20px;
    width: 100%;
    max-width: 500px;
}

.control-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-weight: 500;
}

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

input[type="range"] {
    flex: 1;
    height: 6px;
    background: var(--secondary-color);
    border-radius: 3px;
    outline: none;
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
}

input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    width: 20px;
    height: 20px;
    background: var(--primary-color);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0,0,0,0.3);
}

input[type="range"]::-moz-range-thumb {
    appearance: none;
    -moz-appearance: none;
    width: 20px;
    height: 20px;
    background: var(--primary-color);
    border-radius: 50%;
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 6px rgba(0,0,0,0.3);
}

.value-display {
    min-width: 40px;
    text-align: center;
    color: var(--text-primary);
    font-weight: bold;
}

select {
    width: 100%;
    padding: 10px;
    background-color: var(--background-dark);
    color: var(--text-primary);
    border: 1px solid var(--secondary-color);
    border-radius: var(--border-radius);
    font-size: 16px;
}

select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(40, 160, 255, 0.2);
}

#saveBtn {
    width: 100%;
    max-width: 350px;
    padding: 15px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--text-primary);
    border: none;
    border-radius: var(--border-radius);
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    margin: 20px auto 0;
    display: block;
}

#saveBtn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(40, 160, 255, 0.4);
}

#canvas {
    border: 3px solid var(--secondary-color);
    border-radius: var(--border-radius);
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    background-color: var(--card-background);
    width: 100%;
    height: auto;
    aspect-ratio: 1;
    max-width: 300px;
    align-self: center;
}

.action-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    width: 100%;
}

.btn-primary, .btn-secondary {
    padding: 12px 20px;
    border: none;
    border-radius: var(--border-radius);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    flex: 1;
    max-width: 150px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--text-primary);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(40, 160, 255, 0.4);
}

.btn-secondary {
    background-color: var(--success-color);
    color: var(--text-primary);
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 217, 163, 0.4);
}

.controls-section {
    width: 100%;
    background-color: var(--card-background);
    padding: 20px;
    border-radius: var(--border-radius);
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
}

.slider-group {
    margin-bottom: 15px;
}

.slider-group:last-child {
    margin-bottom: 0;
}

.slider-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 14px;
}

.slider-container {
    display: flex;
    align-items: center;
    gap: 10px;
}

.slider-container input[type="range"] {
    flex: 1;
    height: 6px;
    background: var(--secondary-color);
    border-radius: 3px;
    outline: none;
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
}

.slider-container input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    width: 18px;
    height: 18px;
    background: var(--primary-color);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0,0,0,0.3);
}

.slider-container input[type="range"]::-moz-range-thumb {
    appearance: none;
    -moz-appearance: none;
    width: 18px;
    height: 18px;
    background: var(--primary-color);
    border-radius: 50%;
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 6px rgba(0,0,0,0.3);
}

.value-display {
    min-width: 35px;
    text-align: center;
    color: var(--text-primary);
    font-weight: bold;
    font-size: 14px;
}

.frame-selection {
    width: 100%;
    text-align: center;
}

.frame-selection h3 {
    margin: 0 0 15px 0;
    color: var(--text-secondary);
    font-size: 16px;
    font-weight: 600;
}

.frame-icons {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

.frame-icon {
    width: 80px;
    height: 80px;
    border: 2px solid var(--secondary-color);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s ease;
    overflow: hidden;
    background-color: var(--card-background);
}

.frame-icon:hover {
    border-color: var(--primary-color);
    transform: scale(1.05);
}

.frame-icon.selected {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(40, 160, 255, 0.3);
}

.frame-preview {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--background-dark);
}

.frame-preview.no-frame {
    background-color: var(--card-background);
    border: 1px dashed var(--secondary-color);
}

.frame-preview.no-frame span {
    color: var(--text-secondary);
    font-size: 12px;
    text-align: center;
}

.frame-preview img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Mobile optimizations */
@media (max-width: 480px) {
    main {
        padding: 15px 5px;
    }

    .app-container {
        max-width: 100%;
        gap: 15px;
    }

    #canvas {
        max-width: 280px;
    }

    .action-buttons {
        flex-direction: column;
        gap: 10px;
    }

    .btn-primary, .btn-secondary {
        max-width: none;
    }

    .controls-section {
        padding: 15px;
    }

    .frame-icon {
        width: 70px;
        height: 70px;
    }
}