/* Basic Reset & Defaults */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    /* Light Theme (Default) */
    --bg-color: #ffffff;
    --text-color: #24292f; /* GitHub-like text */
    --primary-color: #0969da; /* GitHub blue */
    --secondary-color: #f6f8fa; /* GitHub light grey */
    --border-color: #d0d7de; /* GitHub border */
    --link-color: #0969da;
    --pre-bg-color: #f6f8fa;
    --modal-bg: rgba(0, 0, 0, 0.4);
    --modal-content-bg: #ffffff;
    --button-text-color: #ffffff;
    --button-secondary-bg: #2c313a; /* GitHub secondary button */
    --button-secondary-hover-bg: #444c56;
    --button-secondary-text-color: #cdd9e5;
    --error-bg: #ffebe9;
    --error-text: #d73a49;
    --error-border: #ffccc7;
    --success-bg: #dafbe1;
    --success-text: #1f883d;
    --success-border: #abe8b8;
    --info-bg: #ddf4ff;
    --info-text: #0969da;
    --info-border: #b6e3ff;
    --warning-bg: #fff8c5;
    --warning-text: #9a6700;
    --warning-border: #ffec80;


    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
    --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
}

html.dark-mode {
    /* Dark Theme */
    --bg-color: #0d1117; /* GitHub dark bg */
    --text-color: #c9d1d9; /* GitHub dark text */
    --primary-color: #58a6ff; /* GitHub dark blue */
    --secondary-color: #161b22; /* GitHub dark grey */
    --border-color: #30363d; /* GitHub dark border */
    --link-color: #58a6ff;
    --pre-bg-color: #161b22;
    --modal-bg: rgba(0, 0, 0, 0.6);
    --modal-content-bg: #161b22;
    --button-text-color: #ffffff;
    --button-secondary-bg: #21262d;
    --button-secondary-hover-bg: #30363d;
    --button-secondary-text-color: #c9d1d9;
    --error-bg: #2f1a1c;
    --error-text: #f85149;
    --error-border: #502426;
    --success-bg: #172d1f;
    --success-text: #56d364;
    --success-border: #2a4631;
    --info-bg: #112a40;
    --info-text: #58a6ff;
    --info-border: #1e415c;
    --warning-bg: #3a2d0b;
    --warning-text: #e3b341;
    --warning-border: #57461a;
}

html {
    font-size: 16px; /* Base font size */
}

body {
    font-family: var(--font-sans);
    line-height: 1.6;
    background-color: var(--bg-color);
    color: var(--text-color);
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: background-color 0.2s ease, color 0.2s ease;
}

header {
    background-color: var(--secondary-color);
    border-bottom: 1px solid var(--border-color);
    padding: 0.75rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background-color 0.2s ease, border-color 0.2s ease;
}

header h1 {
    font-size: 1.25rem; /* Slightly smaller */
    font-weight: 600;
    margin: 0;
}

header nav {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

header nav a,
header nav button {
    color: var(--text-color);
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.1rem; /* Adjust size for icons */
    padding: 0.2rem;
    display: flex;
    align-items: center;
    border-radius: 4px; /* Subtle rounding */
    transition: color 0.2s ease, background-color 0.2s ease;
}
header nav a:hover,
header nav button:hover {
    color: var(--link-color);
    background-color: color-mix(in srgb, var(--border-color) 20%, transparent); /* Subtle hover */
}
header nav button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 1px;
}


main {
    flex-grow: 1;
    padding: 1.5rem;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
}

section {
    margin-bottom: 2rem;
}

h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.3em;
    font-weight: 600;
    color: var(--text-color); /* Match text color */
}

/* Upload Area */
#drop-zone {
    border: 2px dashed var(--border-color);
    border-radius: 6px;
    padding: 2rem 1rem;
    text-align: center;
    background-color: var(--secondary-color);
    margin-bottom: 1rem;
    transition: background-color 0.2s ease, border-color 0.2s ease;
    cursor: pointer;
}

#drop-zone.drag-over {
    border-color: var(--primary-color);
    background-color: color-mix(in srgb, var(--primary-color) 10%, var(--secondary-color));
}

#drop-zone p {
    margin-bottom: 0.5rem;
    color: var(--text-color);
    pointer-events: none; /* Prevent text selection interfering with drop */
}

.button, button {
    display: inline-block;
    padding: 0.5rem 1rem; /* GitHub-like padding */
    background-color: var(--primary-color);
    color: var(--button-text-color);
    border: 1px solid var(--primary-color); /* Add border */
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.875rem; /* 14px */
    font-weight: 500;
    line-height: 1.25; /* 20px */
    text-align: center;
    transition: background-color 0.2s ease, border-color 0.2s ease, opacity 0.2s ease;
    vertical-align: middle; /* Align nicely with text */
    margin-right: 0.5rem; /* Spacing between buttons */
}
/* Ensure button resets */
button {
    font-family: inherit;
}

.button:hover, button:hover {
    background-color: color-mix(in srgb, var(--primary-color) 85%, black);
    border-color: color-mix(in srgb, var(--primary-color) 85%, black);
    text-decoration: none; /* Remove underline on hover */
}
.button:focus-visible, button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary-color) 30%, transparent);
}


button:disabled {
    opacity: 0.65;
    cursor: not-allowed;
    background-color: var(--primary-color); /* Keep color but make opaque */
    border-color: var(--primary-color);
}

/* Secondary Button Style */
.button-secondary {
    background-color: var(--button-secondary-bg);
    color: var(--button-secondary-text-color);
    border-color: var(--border-color); /* Use standard border or a slightly darker one */
}
.button-secondary:hover {
    background-color: var(--button-secondary-hover-bg);
    border-color: var(--border-color);
}
.button-secondary:disabled {
     background-color: var(--button-secondary-bg);
     border-color: var(--border-color);
     opacity: 0.65;
}


#file-info {
    margin-top: 0.75rem;
    font-size: 0.875rem;
    color: var(--text-color);
}

/* Status Area */
#status-area {
    padding: 0.75rem 1rem;
    margin-bottom: 1.5rem;
    border-radius: 6px;
    font-size: 0.875rem;
    border: 1px solid transparent;
    display: none; /* Initially hidden */
}
#status-area.success {
    background-color: var(--success-bg);
    color: var(--success-text);
    border-color: var(--success-border);
    display: block;
}
#status-area.error {
    background-color: var(--error-bg);
    color: var(--error-text);
    border-color: var(--error-border);
    display: block;
}
#status-area.info {
    background-color: var(--info-bg);
    color: var(--info-text);
    border-color: var(--info-border);
    display: block;
}
#status-area.warning { /* Added warning style */
    background-color: var(--warning-bg);
    color: var(--warning-text);
    border-color: var(--warning-border);
    display: block;
}


/* Converter Output Area */
#converter-output {
    display: flex;
    gap: 1.5rem;
    min-height: 400px;
}

/* Style to hide preview area if disabled */
#converter-output.preview-disabled #preview-area {
    display: none;
}
/* Adjust markdown area to take full width if preview is disabled */
#converter-output.preview-disabled #markdown-output-area {
    flex-basis: 100%;
    max-width: 100%; /* Ensure it doesn't overflow */
}

#markdown-output-area,
#preview-area {
    flex: 1 1 50%; /* Allow shrinking and growing, base 50% */
    min-width: 0; /* Prevent flex items from overflowing */
    display: flex;
    flex-direction: column;
    background-color: var(--bg-color); /* Match body background */
    border: 1px solid var(--border-color);
    border-radius: 6px;
    overflow: hidden;
    transition: flex-basis 0.3s ease, max-width 0.3s ease, display 0.3s ease;
}

#converter-output h2 { /* Section headers within output area */
    padding: 0.5rem 1rem;
    margin: 0;
    border: none;
    background-color: var(--secondary-color);
    border-bottom: 1px solid var(--border-color);
    font-size: 0.875rem; /* Smaller header */
    font-weight: 600;
    line-height: 1.5;
}

#converter-output .controls {
    padding: 0.5rem 1rem;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--secondary-color);
    display: flex;
    gap: 0.5rem;
    align-items: center;
    flex-wrap: wrap; /* Allow controls to wrap */
    justify-content: flex-start; /* Align to the left by default */
}

#converter-output .controls button {
    padding: 0.25rem 0.75rem; /* Smaller buttons */
    font-size: 0.8rem;
}

#clear-file-button {
    margin-left: auto; /* Push to the right */
}

#copy-markdown-button, #download-markdown-button {
    margin-right: 0.25rem; /* Reduced margin between first two buttons */
}

#converter-output .controls .note {
    font-size: 0.8rem;
    color: var(--text-color);
    opacity: 0.8;
}

#markdown-output { /* Textarea */
    flex-grow: 1;
    width: 100%;
    border: none;
    padding: 1rem;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.5;
    background-color: var(--bg-color);
    color: var(--text-color);
    resize: none;
    outline: none;
    min-height: 200px; /* Ensure minimum height */
}

#html-preview { /* Preview Div */
    flex-grow: 1;
    padding: 1rem;
    background-color: var(--bg-color);
    color: var(--text-color);
    overflow-y: auto;
    word-wrap: break-word;
    min-height: 200px; /* Ensure minimum height */
}

/* Styles for rendered Markdown content (like GitHub) */
.markdown-body {
    font-family: var(--font-sans);
    line-height: 1.6;
    font-size: 1rem;
}
.markdown-body > *:first-child { margin-top: 0 !important; }
.markdown-body h1, .markdown-body h2, .markdown-body h3, .markdown-body h4, .markdown-body h5, .markdown-body h6 {
    margin-top: 24px;
    margin-bottom: 16px;
    font-weight: 600;
    line-height: 1.25;
    color: var(--text-color);
}
.markdown-body h1 { font-size: 2em; border-bottom: 1px solid var(--border-color); padding-bottom: 0.3em; }
.markdown-body h2 { font-size: 1.5em; border-bottom: 1px solid var(--border-color); padding-bottom: 0.3em; }
.markdown-body h3 { font-size: 1.25em; }
.markdown-body h4 { font-size: 1em; }
.markdown-body h5 { font-size: .875em; }
.markdown-body h6 { font-size: .85em; color: #6a737d; } /* Dim h6 slightly */
.markdown-body p { margin-bottom: 16px; }
.markdown-body ul, .markdown-body ol { margin-bottom: 16px; padding-left: 2em; }
.markdown-body li { margin-bottom: 0.25em; }
.markdown-body li > ul, .markdown-body li > ol { margin-top: 0.25em; margin-bottom: 0;}
.markdown-body blockquote {
    margin-left: 0;
    margin-right: 0;
    margin-bottom: 16px;
    padding: 0 1em;
    color: color-mix(in srgb, var(--text-color) 75%, transparent);
    border-left: 0.25em solid var(--border-color);
    /* background-color: var(--secondary-color); // Optional subtle background */
}
.markdown-body blockquote > :first-child { margin-top: 0; }
.markdown-body blockquote > :last-child { margin-bottom: 0; }

.markdown-body code {
    font-family: var(--font-mono);
    font-size: 85%;
    background-color: color-mix(in srgb, var(--border-color) 30%, transparent);
    padding: 0.2em 0.4em;
    border-radius: 6px;
    margin: 0 0.1em; /* Slight spacing */
}
.markdown-body pre {
    font-family: var(--font-mono);
    background-color: var(--pre-bg-color);
    padding: 16px;
    border-radius: 6px;
    overflow: auto; /* Changed from overflow-x for vertical scroll too */
    margin-bottom: 16px;
    font-size: 85%;
    line-height: 1.45;
    border: 1px solid var(--border-color); /* Subtle border */
}
.markdown-body pre code {
    padding: 0;
    margin: 0;
    background-color: transparent;
    border: none;
    font-size: 100%; /* Inherit size from pre */
    line-height: inherit; /* Inherit line height */
    word-wrap: normal; /* Prevent wrapping within code block */
}
.markdown-body table {
    border-collapse: collapse;
    margin-top: 0;
    margin-bottom: 16px;
    display: block;
    width: max-content;
    max-width: 100%;
    overflow: auto;
    border-spacing: 0;
    border: 1px solid var(--border-color); /* Outer border */
}
.markdown-body th, .markdown-body td {
    border: 1px solid var(--border-color);
    padding: 6px 13px;
}
.markdown-body thead th { /* Header specific */
     background-color: var(--secondary-color);
     font-weight: 600;
     border-top: none; /* Remove double border */
     border-left: none;
     border-right: none;
}
.markdown-body tr {
     background-color: var(--bg-color);
     border-top: 1px solid var(--border-color);
}
.markdown-body tbody tr:nth-child(odd) { /* Subtle striping */
     background-color: var(--secondary-color);
}
.markdown-body tbody tr:hover { /* Hover effect */
    background-color: color-mix(in srgb, var(--primary-color) 5%, var(--secondary-color));
}
.markdown-body img {
    max-width: 100%;
    height: auto;
    background-color: var(--bg-color);
    box-sizing: content-box; /* GitHub style */
}
.markdown-body a {
    color: var(--link-color);
    text-decoration: none;
}
.markdown-body a:hover {
    text-decoration: underline;
}
.markdown-body hr {
    border: 0;
    height: .25em;
    padding: 0;
    margin: 24px 0;
    background-color: var(--border-color);
    border: 0;
}


/* Settings Modal */
.modal {
    position: fixed;
    inset: 0;
    background-color: var(--modal-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
}

.modal.visible {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background-color: var(--modal-content-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 0;
    max-width: 600px; /* Slightly wider */
    width: 90%;
    max-height: 85vh;
    display: flex;
    flex-direction: column;
    box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
}

#close-settings-button {
    background: none;
    border: none;
    font-size: 1.6rem;
    line-height: 1;
    color: var(--text-color);
    cursor: pointer;
    padding: 0 0.2rem;
    opacity: 0.7;
    transition: opacity 0.2s ease;
}
#close-settings-button:hover {
    opacity: 1;
}
#close-settings-button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 1px;
}


.modal-body {
    padding: 1.5rem;
    overflow-y: auto;
}

.modal-body fieldset {
    border: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    margin-bottom: 1.5rem;
    border-radius: 6px;
    background-color: var(--secondary-color); /* Subtle background for fieldsets */
}

.modal-body legend {
    padding: 0 0.5rem;
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-color);
    background-color: var(--modal-content-bg); /* Match modal background to 'cut out' border */
}

.modal-body label {
    display: block;
    margin-bottom: 0.75rem;
    cursor: pointer;
    font-size: 0.875rem;
}
.modal-body label:last-of-type {
    margin-bottom: 0; /* Remove margin from last label in group */
}

.modal-body label input[type="radio"],
.modal-body label input[type="checkbox"] {
    margin-right: 0.5rem;
    vertical-align: middle; /* Align better with text */
}
.modal-body input[type="text"] { /* If added later */
    width: 100%;
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin-top: 0.2rem;
    font-size: 0.875rem;
}
.modal-body input[type="text"]:focus {
     border-color: var(--primary-color);
     outline: none;
     box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary-color) 30%, transparent);
}

/* Settings Action Buttons container */
.settings-actions {
    display: flex;
    justify-content: flex-end; /* Align buttons to the right */
    gap: 0.5rem; /* Space between buttons */
    margin-top: 1rem;
    padding-top: 1rem; /* Space above buttons */
    border-top: 1px solid var(--border-color); /* Separator line */
}
.settings-actions button {
     margin-right: 0; /* Remove default margin if using gap */
}

/* Loader Overlay */
.loader-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.6);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    visibility: hidden;
    opacity: 0;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}
.loader-overlay.visible {
    visibility: visible;
    opacity: 1;
}

.spinner {
    border: 5px solid var(--secondary-color);
    border-top: 5px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 0.8s linear infinite;
    margin-bottom: 1rem;
}

#loader-message {
    color: #ffffff;
    font-size: 1rem;
    font-weight: 500;
}

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


/* Utility Classes */
.hidden {
    display: none !important; /* Use important if needed to override */
}

/* Responsiveness */
@media (max-width: 768px) {
    html { font-size: 15px; } /* Adjust base size slightly */
    header { padding: 0.5rem 1rem; }
    header h1 { font-size: 1.1rem; }
    main { padding: 1rem; }
    #converter-output {
        flex-direction: column;
        min-height: auto;
    }
    #markdown-output-area,
    #preview-area {
        min-height: 250px; /* Adjust height */
        flex-basis: auto; /* Reset flex basis */
        max-width: none; /* Reset max width */
    }
    .modal-content {
        width: 95%;
        max-height: 90vh;
    }
    .settings-actions {
        flex-direction: column; /* Stack buttons on small screens */
        align-items: stretch; /* Make buttons full width */
    }
    .settings-actions button {
        width: 100%;
    }

}