:root {
    --primary-color: #3498db;
    --secondary-color: #2980b9;
    --text-color: #333;
    --bg-color: #f8f9fa;
    --container-bg: #ffffff;
    --error-color: #e74c3c;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --border-color: #e1e1e1;
}

.dark-theme {
    --primary-color: #4dabf7;
    --secondary-color: #339af0;
    --text-color: #f8f9fa;
    --bg-color: #121212;
    --container-bg: #1e1e1e;
    --error-color: #ff6b6b;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --border-color: #2d2d2d;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s, color 0.3s;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    padding: 0;
    margin: 0;
}

/* Page wrapper for main content and sidebars */
.page-wrapper {
    display: flex;
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    justify-content: space-between;
    flex-wrap: wrap;
}

/* Header ad space */
.header-ad {
    width: 100%;
    height: 90px;
    background-color: var(--container-bg);
    border-radius: 8px;
    margin: 10px auto;
    display: flex;
    align-items: center;
    justify-content: center;
    max-width: 1200px;
    box-shadow: 0 2px 8px var(--shadow-color);
}

/* Sidebar ad spaces */
.sidebar-ad {
    width: 160px;
    min-height: 600px;
    background-color: var(--container-bg);
    border-radius: 8px;
    margin: 0 10px;
    box-shadow: 0 2px 8px var(--shadow-color);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}

/* Ad styling */
.ad-placeholder {
    color: #999;
    text-align: center;
    font-size: 14px;
    padding: 10px;
}

.custom-ad {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 10px;
    text-align: center;
}

.custom-ad img {
    max-width: 100%;
    height: auto;
    border-radius: 6px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.custom-ad img:hover {
    transform: scale(1.02);
}

.custom-ad h4 {
    margin: 10px 0 5px;
    color: var(--text-color);
}

.custom-ad p {
    margin: 5px 0;
    font-size: 14px;
    color: var(--text-color);
}

.ad-button {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 6px 12px;
    border-radius: 4px;
    text-decoration: none;
    margin-top: 8px;
    font-size: 14px;
    transition: background-color 0.2s ease;
}

.ad-button:hover {
    background-color: var(--secondary-color);
}

.special-offer {
    margin-top: 10px;
    padding: 8px;
    background-color: #fff3cd;
    border-left: 4px solid #ffc107;
    color: #856404;
    font-size: 14px;
    border-radius: 4px;
}

/* Accessibility */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

/* QR Code Container Styles */
.qr-container {
    margin: 30px auto;
    padding: 15px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    max-width: 100%;
    overflow: hidden;
    transition: all 0.3s ease;
}

.qr-container.hidden {
    display: none;
}

.qr-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 20px auto;
    width: 100%;
    background-color: white;
    padding: 0;
    border: none;
    box-shadow: none;
}

#qrCode {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 0 auto;
    width: 250px;
    height: 250px;
    background-color: white;
    padding: 0;
    border: 1px solid #ddd;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    position: relative;
}

#qrCode svg, #qrCode canvas, #qrCode img {
    width: 100%;
    height: 100%;
    display: block;
}

#qrious-canvas {
    image-rendering: pixelated;
    image-rendering: crisp-edges;
    background-color: white;
    width: 250px !important;
    height: 250px !important;
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    margin: auto;
}

.qr-buttons {
    margin-top: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.download-btn {
    padding: 12px 24px;
    font-size: 16px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.download-btn:hover {
    background-color: #45a049;
}

.scan-note {
    margin-top: 10px;
    color: #666;
    font-size: 14px;
    text-align: center;
}

.container {
    background-color: var(--container-bg);
    border-radius: 12px;
    box-shadow: 0 8px 24px var(--shadow-color);
    padding: 20px;
    width: 100%;
    max-width: 600px;
    text-align: center;
    margin-bottom: 20px;
}

h1 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 2.2rem;
}

.description {
    margin-bottom: 15px;
    color: var(--text-color);
    font-size: 1rem;
    opacity: 0.8;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 15px;
    margin-bottom: 20px;
}

input {
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    width: 100%;
    background-color: var(--container-bg);
    color: var(--text-color);
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    padding: 12px 20px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

button:hover {
    background-color: var(--secondary-color);
}

button:active {
    transform: scale(0.98);
}

.error-message {
    color: var(--error-color);
    font-size: 0.9rem;
    margin-bottom: 5px;
    min-height:5px;
}

.qr-container {
    margin-top: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}

.style-options {
    margin-top: 5px;
    background-color: var(--container-bg);
    border-radius: 8px;
    padding: 15px;
    box-shadow: 0 4px 8px var(--shadow-color);
}

.style-options h3 {
    margin-bottom: 15px;
    font-size: 1.2rem;
    color: var(--primary-color);
    text-align: center;
}

.style-options h4 {
    margin: 15px 0 10px;
    font-size: 1rem;
    color: var(--text-color);
    opacity: 0.9;
}

.preset-styles {
    margin-bottom: 20px;
}

.preset-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
}

.preset-btn {
    padding: 8px 15px;
    font-size: 0.9rem;
    border-radius: 20px;
    background-color: var(--bg-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.preset-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.preset-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.options-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.option-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.option-group label {
    font-size: 0.9rem;
    opacity: 0.8;
}

select, input[type="color"], input[type="file"], input[type="range"] {
    padding: 8px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    background-color: var(--container-bg);
    color: var(--text-color);
    font-size: 0.9rem;
}

input[type="color"] {
    height: 40px;
    cursor: pointer;
}

input[type="file"] {
    width: 100%;
    cursor: pointer;
}

input[type="range"] {
    padding: 0;
    height: 6px;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
}

select:focus, input[type="color"]:focus, input[type="range"]:focus {
    outline: none;
    border-color: var(--primary-color);
}

.secondary-btn {
    background-color: var(--bg-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    opacity: 0.8;
}

.secondary-btn:hover {
    background-color: var(--border-color);
}

.secondary-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.qr-container.hidden {
    display: none;
}

#qrCode {
    padding: 15px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 4px 12px var(--shadow-color);
}

.download-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    background-color: var(--primary-color);
}

footer {
    margin-top: auto;
    padding: 15px;
    text-align: center;
    font-size: 0.9rem;
    opacity: 0.7;
}

footer i {
    color: #e74c3c;
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
}

.theme-toggle button {
    background-color: transparent;
    color: var(--text-color);
    font-size: 1.2rem;
    padding: 8px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 10px var(--shadow-color);
    background-color: var(--container-bg);
}

@media (min-width: 768px) {
    .input-group {
        flex-direction: row;
    }
    
    input {
        flex: 1;
    }
    
    #generateBtn {
        white-space: nowrap;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 20px;
    }
    
    h1 {
        font-size: 1.8rem;
    }
    
    .input-group {
        flex-direction: column;
    }
    
    .input-group input {
        width: 100%;
        margin-right: 0;
        margin-bottom: 10px;
    }
    
    .input-group button {
        width: 100%;
    }
    
    .options-container {
        flex-direction: column;
    }
    
    .option-group {
        width: 100%;
        margin-bottom: 15px;
    }
    
    .qr-container {
        padding: 15px;
    }
    
    .preset-buttons {
        flex-wrap: wrap;
    }
    
    .preset-btn {
        margin-bottom: 10px;
    }
    
    /* Responsive ad spaces */
    .page-wrapper {
        flex-direction: column;
        align-items: center;
    }
    
    .sidebar-ad {
        width: 100%;
        min-height: 250px;
        margin: 10px 0;
    }
    
    .sidebar-ad.left-sidebar {
        order: 1;
    }
    
    .container {
        order: 2;
        margin: 10px 0;
    }
    
    .sidebar-ad.right-sidebar {
        order: 3;
    }
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.7);
    animation: fadeIn 0.3s;
}

.modal-content {
    position: relative;
    background-color: var(--bg-color);
    margin: 10% auto;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    max-width: 600px;
    width: 90%;
    animation: slideIn 0.3s;
}

.close-modal-btn {
    position: absolute;
    top: 10px;
    right: 15px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    padding: 5px 10px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.close-modal-btn:hover {
    background-color: #2980b9;
    transform: translateY(-1px);
    box-shadow: 0 3px 6px rgba(0, 0, 0, 0.3);
}

.close-modal-btn:active {
    transform: translateY(0);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

#modalImage {
    width: 100%;
    height: auto;
    border-radius: 5px;
    cursor: pointer;
    transition: transform 0.2s;
}

#modalImage:hover {
    transform: scale(1.02);
}

.modal-caption {
    text-align: center;
    margin-top: 15px;
    color: var(--text-color);
    font-style: italic;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}