:root {
    --primary-color: #4285f4;
    --secondary-color: #34a853;
    --accent-color: #ea4335;
    --light-gray: #f5f5f5;
    --dark-gray: #333;
    --white: #fff;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--dark-gray);
    background-color: var(--light-gray);
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background-color: var(--white);
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    color: var(--primary-color);
    text-align: center;
    margin-bottom: 30px;
}

.tabs {
    display: flex;
    margin-bottom: 20px;
    border-bottom: 1px solid #ddd;
}

.tab-btn {
    padding: 10px 20px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 16px;
    color: var(--dark-gray);
    transition: all 0.3s ease;
    border-bottom: 3px solid transparent;
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
    font-weight: bold;
}

.tab-content {
    display: none;
    padding: 20px 0;
}

.tab-content.active {
    display: block;
}

input[type="url"], 
input[type="file"],
textarea {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

textarea {
    min-height: 100px;
    resize: vertical;
}

button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #3367d6;
}

#decoded-result,
#url-qr-result,
#text-qr-result {
    margin-top: 20px;
    text-align: center;
}

#url-qr-result canvas,
#text-qr-result canvas {
    max-width: 100%;
    height: auto;
    border: 1px solid #eee;
    padding: 10px;
    background: white;
}

@media (max-width: 600px) {
    .tabs {
        flex-direction: column;
    }
    
    .tab-btn {
        text-align: left;
        border-bottom: none;
        border-left: 3px solid transparent;
    }
    
    .tab-btn.active {
        border-left-color: var(--primary-color);
    }
}