/* Basic Reset */
:root {
    --color-primary: #007bff;
    --color-secondary: #6c757d;
    --color-background: #f8f9fa;
    --color-card-bg: #ffffff;
    --color-text: #343a40;
    --color-success: #28a745;
    --color-shadow: rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-background);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    width: 90%;
    max-width: 1000px;
    margin: 0 auto;
    padding: 1rem 0;
}

/* Header */
header {
    background: var(--color-card-bg);
    border-bottom: 1px solid #dee2e6;
    box-shadow: 0 2px 4px var(--color-shadow);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1rem;
}

header h1 {
    font-size: 1.5rem;
    color: var(--color-primary);
}

.built-with a {
    color: var(--color-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s;
}

.built-with a:hover {
    color: var(--color-primary);
    text-decoration: underline;
}

/* Main Content */
main {
    flex-grow: 1;
    padding-top: 2rem;
    padding-bottom: 3rem;
}

h2 {
    color: var(--color-primary);
    margin-bottom: 1.5rem;
    font-size: 1.75rem;
    border-bottom: 2px solid #e9ecef;
    padding-bottom: 0.5rem;
}

/* Form Styling */
#vlm-input {
    background: var(--color-card-bg);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 12px var(--color-shadow);
    margin-bottom: 2rem;
}

.input-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    font-weight: bold;
    margin-bottom: 0.5rem;
    color: var(--color-text);
}

textarea, input[type="text"] {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ced4da;
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s, box-shadow 0.3s;
}

textarea:focus, input[type="text"]:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
    outline: none;
}

/* File Upload Area */
.file-upload-area {
    text-align: center;
}

#image-upload {
    /* Hide the default input, rely on custom preview area interaction */
    display: none;
}

.image-preview {
    border: 2px dashed #adb5bd;
    border-radius: 8px;
    padding: 2rem;
    cursor: pointer;
    background-color: #e9ecef;
    transition: background-color 0.3s, border-color 0.3s;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 200px;
    position: relative;
    overflow: hidden;
}

.image-preview:hover {
    background-color: #dee2e6;
    border-color: var(--color-primary);
}

.image-preview i {
    font-size: 3rem;
    color: var(--color-secondary);
    margin-bottom: 0.5rem;
}

.image-preview p {
    color: var(--color-secondary);
    font-size: 0.9rem;
}

#preview-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: contain; /* Ensure the whole image is visible */
    background-color: var(--color-card-bg);
}

.image-preview.has-image i, 
.image-preview.has-image p {
    display: none;
}
.image-preview.has-image #preview-img {
    object-fit: cover; /* Use cover when image is loaded */
}


/* Button */
#submit-btn {
    display: block;
    width: 100%;
    padding: 1rem;
    border: none;
    border-radius: 4px;
    background-color: var(--color-primary);
    color: white;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.3s, opacity 0.3s;
}

#submit-btn:hover:not(:disabled) {
    background-color: #0056b3;
}

#submit-btn:disabled {
    background-color: var(--color-secondary);
    opacity: 0.7;
    cursor: not-allowed;
}

/* VLM Output Area */
#vlm-output {
    margin-top: 2rem;
}

.response-card {
    background: var(--color-card-bg);
    padding: 1.5rem;
    border-left: 5px solid var(--color-success);
    border-radius: 4px;
    box-shadow: 0 2px 8px var(--color-shadow);
    min-height: 150px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: left;
}

#response-text {
    white-space: pre-wrap;
    font-family: monospace;
    font-size: 1rem;
    color: var(--color-text);
    padding: 0;
    margin: 0;
}

/* Utility */
.hidden {
    display: none !important;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Spinner */
.spinner {
    border: 4px solid rgba(0, 0, 0, 0.1);
    border-top: 4px solid var(--color-primary);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 1rem auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Footer */
footer {
    background: var(--color-text);
    color: white;
    text-align: center;
    padding: 1rem 0;
    margin-top: auto;
}

footer p {
    font-size: 0.9rem;
}

/* Responsiveness */
@media (min-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    .header-content {
        padding: 1rem 0;
    }
    
    #vlm-input {
        padding: 2rem;
    }
    
    #submit-btn {
        width: 50%;
        margin: 0 auto;
    }

    /* Layout adjustment for larger screens (if needed, though single column is fine here) */
}