:root {
    --bg-color: #ffffff;
    --text-color: #000000;
    --border-color: #000000;
    --accent-color: #000000;
    --input-bg: #ffffff;
    
    /* Typography */
    --font-serif: "Georgia", "Times New Roman", Times, serif;
    --font-mono: "Courier New", Courier, "Lucida Sans Typewriter", monospace;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-serif);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* Layout */
.app-container {
    display: grid;
    grid-template-columns: 1fr;
    min-height: 100vh;
    border-top: 5px solid var(--border-color); /* The "Masthead" thick line */
}

.pane {
    padding: 2rem 2.5rem;
    position: relative;
}

/* Header */
header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 2rem;
    letter-spacing: -0.05rem;
    line-height: 1;
    text-transform: uppercase;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1rem;
}

hr {
    border: 0;
    border-bottom: 1px solid var(--border-color);
    margin: 2rem 0;
}

/* Inputs Pane */
.input-pane {
    background: var(--bg-color);
}

/* Controls */
.control-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* The "Unorthodox" Input Style */
input, textarea, select {
    width: 100%;
    padding: 1rem;
    background-color: transparent;
    border: 1px solid var(--border-color);
    border-radius: 0; /* Crucial */
    
    /* Typography mix */
    font-family: var(--font-mono);
    font-size: 1rem;
    color: var(--text-color);
    
    /* Remove native OS styles */
    appearance: none;
    -webkit-appearance: none;
    box-shadow: none;
}

input:focus, textarea:focus, select:focus {
    outline: 2px solid var(--text-color);
    outline-offset: -2px;
    background-color: #fff;
}

/* Custom Dropdown Arrow for the Brutalist look */
select {
    background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" viewBox="0 0 24 24"><path d="M0 7.33l2.829-2.83 9.175 9.339 9.167-9.339 2.829 2.83-11.996 12.17z"/></svg>');
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 12px;
    cursor: pointer;
}

.input-form {
    display: none;
    animation: fadeIn 0.3s ease;
}

.input-form.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Preview Pane */
.preview-pane {
    display: flex;
    flex-direction: column;
    align-items: center;
    /* Create a texture or distinct feel for the right side? 
       Let's keep it stark white but separated by a border. */
    background-color: var(--bg-color);
}

.sticky-wrapper {
    width: 100%;
    max-width: 320px;
    padding-top: 1rem;
}

/* QR Container */
#qr-container {
    width: 256px;
    height: 256px;
    margin: 0 auto 2rem auto;
    
    /* The "Frame" */
    border: 1px solid var(--border-color);
    padding: 10px; /* Mat frame */
    display: flex;
    align-items: center;
    justify-content: center;
    
    /* Hard transition, no fading */
    transition: none; 
}

#qr-container img, #qr-container canvas {
    display: block;
    max-width: 100%;
    /* Ensure crisp edges */
    image-rendering: pixelated; 
}

/* The Button - Brutalist */
button {
    width: 100%;
    padding: 1rem;
    background-color: var(--text-color); /* Black */
    color: var(--bg-color); /* White */
    border: 1px solid var(--text-color);
    border-radius: 0;
    
    font-family: var(--font-mono);
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    cursor: pointer;
    transition: all 0.1s;
}

button:hover:not(:disabled) {
    background-color: var(--bg-color);
    color: var(--text-color);
    /* The border remains black, creating an "invert" effect */
}

button:disabled {
    background-color: #f0f0f0;
    color: #aaa;
    border-color: #ccc;
    cursor: not-allowed;
    text-decoration: line-through; /* A little edgy touch */
}

/* Desktop Grid */
@media (min-width: 768px) {
    .app-container {
        grid-template-columns: 400px 1fr; /* Fixed width sidebar, fluid content */
        max-width: 100%;
        margin: 0;
        border-top: none; /* Remove top border on desktop */
    }

    .input-pane {
        border-right: 1px solid var(--border-color); /* Vertical divider */
        height: 100vh;
        overflow-y: auto;
    }

    .preview-pane {
        height: 100vh;
        justify-content: center;
        background-image: radial-gradient(#000 0.5px, transparent 0.5px);
        background-size: 20px 20px; /* Subtle dot grid pattern on the right */
    }
    
    /* Make the pattern very subtle */
    .preview-pane {
        background-color: #fdfdfd;
    }

    .sticky-wrapper {
        background: #fff;
        padding: 2rem;
        border: 1px solid black;
        box-shadow: 10px 10px 0px 0px rgba(0,0,0,1); /* Hard block shadow */
    }
}