/*
   TEXT COMPARE - EXPERT WEB TOOLS
*/

@font-face { font-family: 'Inter';       src: url('/fonts/inter-v20-latin-regular.woff2') format('woff2'); font-weight: 400; font-display: swap; }
@font-face { font-family: 'Orbitron';    src: url('/fonts/orbitron-v35-latin-700.woff2')  format('woff2'); font-weight: 700; font-display: swap; }
@font-face { font-family: 'Roboto Mono'; src: url('/fonts/roboto-mono-v31-latin-regular.woff2') format('woff2'); font-weight: 400; font-display: swap; }

/* Base Dark Theme Variables (Default) */
:root {
    --bg-main:          #0a0a0f;
    --primary-accent:   #3b82f6;
    --secondary-accent: #8b5cf6;
    --text-main:        #ffffff;
    --text-muted:       #94a3b8;
    --card-bg:          rgba(25, 25, 35, 0.6);
    --card-border:      rgba(255, 255, 255, 0.08);
    --input-bg:         rgba(255, 255, 255, 0.05);
    --editor-bg:        #1e1e1e;
    --toggle-bg:        rgba(0,0,0,0.3);
    --toast-bg:         #1e1e24;
    --code-bg:          rgba(59,130,246,0.12);
    --code-border:      rgba(59,130,246,0.2);
    --code-color:       #93c5fd;
    --select-bg:        var(--input-bg);
    --select-text:      #ffffff;
    --select-opt-bg:    #0a0a0f;
    --scroll-track:     rgba(0,0,0,0.2);
    --scroll-thumb:     rgba(255,255,255,0.15);
    --scroll-thumb-hover: rgba(255,255,255,0.3);
    
    --select-arrow:     url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2394a3b8'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    
    --font-heading:     'Orbitron', sans-serif;
    --font-body:        'Inter', sans-serif;
    --font-code:        'Roboto Mono', monospace;
}

/* Light Mode Variables */
html.light-theme {
    --bg-main:          #faf9f6;
    --primary-accent:   #2563eb;
    --text-main:        #0f172a;
    --text-muted:       #475569;
    --card-bg:          #ffffff;
    --card-border:      #cbd5e1;
    --input-bg:         #f8fafc;
    --editor-bg:        #ffffff;
    --toggle-bg:        #e2e8f0;
    --toast-bg:         #ffffff;
    --code-bg:          #eff6ff;
    --code-border:      #bfdbfe;
    --code-color:       #1d4ed8;
    --select-bg:        #ffffff;
    --select-text:      #0f172a;
    --select-opt-bg:    #ffffff;
    --scroll-track:     rgba(0,0,0,0.05);
    --scroll-thumb:     rgba(0,0,0,0.2);
    --scroll-thumb-hover: rgba(0,0,0,0.3);
    
    --select-arrow:     url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%23475569'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
}

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

::-webkit-scrollbar        { width: 8px; height: 8px; }
::-webkit-scrollbar-track  { background: var(--scroll-track); border-radius: 4px; }
::-webkit-scrollbar-thumb  { background: var(--scroll-thumb); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--scroll-thumb-hover); }

html {
    width: 100%;
}

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

.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;
}

.background-glow {
    position: fixed; top: -50%; left: -50%; width: 200%; height: 200%;
    background: radial-gradient(circle at center, rgba(59,130,246,0.08) 0%, rgba(10,10,15,0) 50%);
    z-index: -1; pointer-events: none;
}

html.light-theme .background-glow { display: none; }

/* --- Header --- */
.tool-header {
    display: flex; justify-content: space-between; align-items: center;
    padding: 1.5rem 5%; max-width: 1400px; margin: 0 auto; width: 100%;
    flex-wrap: wrap; gap: 10px;
}
.back-btn {
    color: var(--text-muted); text-decoration: none;
    display: flex; align-items: center; gap: 8px;
    transition: color 0.3s; border-radius: 4px; padding: 2px 4px;
}
.back-btn:hover         { color: var(--primary-accent); }
.back-btn:focus-visible { outline: 2px solid var(--primary-accent); color: var(--primary-accent); }
.logo      { font-family: var(--font-heading); font-size: 1.2rem; color: var(--text-main); flex-grow: 1; text-align: center; }
.logo span { color: var(--primary-accent); }

.theme-toggle-btn {
    background: transparent; border: 1px solid var(--card-border); border-radius: 6px;
    color: var(--text-muted); cursor: pointer; padding: 8px 12px;
    transition: all 0.2s; font-size: 1rem;
    display: flex; align-items: center; justify-content: center;
}
.theme-toggle-btn:hover { background: var(--toggle-bg); color: var(--text-main); }
.theme-toggle-btn:focus-visible { outline: 2px solid var(--primary-accent); }

/* --- Main Layout --- */
.main-content   { flex-grow: 1; padding: 2rem 5%; max-width: 1400px; margin: 0 auto; width: 100%; }

.tool-container {
    background: var(--card-bg); border: 1px solid var(--card-border);
    border-radius: 16px; padding: 2rem;
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
    transition: background-color 0.2s ease, border-color 0.2s;
    min-width: 0;
}

.tool-intro    { text-align: center; margin-bottom: 2rem; }
.tool-intro h1 { font-family: var(--font-heading); margin-bottom: 0.5rem; font-size: 2rem; line-height: 1.2; }
.tool-intro p  { color: var(--text-muted); }
.tool-intro .h1-ampersand { font-family: var(--font-body); font-weight: 300; }

/* Toolbar */
.toolbar {
    display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 1.5rem; padding-bottom: 1rem;
    border-bottom: 1px solid var(--card-border);
    flex-wrap: wrap; gap: 1rem;
    min-width: 0;
}
.control-group { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; min-width: 0; }
.control-group > label { color: var(--text-muted); font-size: 0.95rem; display: flex; align-items: center; gap: 5px; }

.toggle-checkbox       { cursor: pointer; display: flex; align-items: center; gap: 5px; user-select: none; color: var(--text-muted); font-size: 0.95rem; }
.toggle-checkbox input { cursor: pointer; accent-color: var(--primary-accent); width: 15px; height: 15px; margin: 0; }
.toggle-checkbox:focus-within { outline: 2px solid var(--primary-accent); border-radius: 3px; }

/* Regex Input */
.regex-container {
    display: flex; align-items: center; gap: 4px;
}
.regex-input {
    background-color: var(--input-bg);
    border: 1px solid var(--card-border);
    color: var(--text-main);
    padding: 8px 12px;
    border-radius: 6px;
    outline: none;
    font-family: var(--font-code);
    font-size: 0.85rem;
    width: 220px;
    min-height: 44px;
    transition: border-color 0.2s;
}
.regex-input:focus { border-color: var(--primary-accent); }

/* CSP-Safe Pure CSS Tooltips */
.tooltip-wrapper {
    position: relative;
    display: inline-flex;
    align-items: center;
    margin-left: 2px;
}
.tooltip-icon {
    color: var(--text-muted);
    font-size: 0.9rem;
    cursor: help;
    transition: color 0.2s;
}
.tooltip-wrapper:hover .tooltip-icon, .tooltip-wrapper:focus-within .tooltip-icon { 
    color: var(--primary-accent); 
}
.tooltip-content {
    position: absolute;
    bottom: 150%;
    left: 50%;
    transform: translateX(-50%);
    background: var(--toast-bg);
    color: var(--text-main);
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-family: var(--font-body);
    white-space: normal;
    width: max-content;
    max-width: 240px;
    text-align: center;
    border: 1px solid var(--primary-accent);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s, visibility 0.2s, transform 0.2s;
    z-index: 1000;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
    pointer-events: none;
    font-weight: 400;
}
.tooltip-wrapper::before {
    content: '';
    position: absolute;
    bottom: 100%;
    left: 0;
    width: 100%;
    height: 10px;
}
.tooltip-wrapper:hover .tooltip-content, .tooltip-wrapper:focus-within .tooltip-content {
    opacity: 1;
    visibility: visible;
}

select {
    background-color: var(--select-bg); 
    border: 1px solid var(--card-border);
    color: var(--select-text); 
    padding: 8px 36px 8px 12px;
    border-radius: 6px; 
    outline: none;
    cursor: pointer; 
    font-family: var(--font-body); 
    font-size: 0.9rem;
    -webkit-appearance: none; 
    appearance: none;
    min-height: 44px;
    background-image: var(--select-arrow);
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 16px;
    transition: border-color 0.2s;
}
select option         { background-color: var(--select-opt-bg); color: var(--select-text); padding: 10px; }
select:focus-visible  { outline: 2px solid var(--primary-accent); border-color: var(--primary-accent); }

/* Buttons */
.action-group { display: flex; gap: 10px; flex-wrap: wrap; justify-content: flex-end; min-width: 0; }

button {
    border: 1px solid var(--card-border); border-radius: 6px; padding: 10px 20px;
    cursor: pointer; font-weight: 600; font-size: 0.9rem; transition: all 0.2s;
    display: flex; align-items: center; justify-content: center; gap: 8px;
    font-family: var(--font-body); white-space: nowrap;
    min-height: 44px;
}
button:disabled { opacity: 0.7; cursor: not-allowed; }
button:focus-visible { outline: 2px solid var(--primary-accent); }

.primary-btn          { background: var(--primary-accent); color: #fff; border-color: var(--primary-accent); }
.primary-btn:hover:not(:disabled) { background: #2563eb; }
.secondary-btn        { background: transparent; color: var(--text-muted); }
.secondary-btn:hover:not(:disabled) { background: var(--toggle-bg); color: var(--text-main); }
.danger-btn           { background: transparent; color: #ef4444; border-color: rgba(239,68,68,0.3); }
.danger-btn:hover:not(:disabled) { background: rgba(239,68,68,0.1); }
.copy-merged-btn      { padding: 6px 12px; font-size: 0.85rem; margin-left: 4px; min-height: 44px; }

.kbd-hint {
    font-size: 0.75rem; color: rgba(255,255,255,0.7);
    background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.3);
    border-radius: 4px; padding: 2px 6px; font-family: var(--font-code);
    margin-left: 4px; letter-spacing: 0.02em;
}
html.light-theme .kbd-hint { color: rgba(255,255,255,0.9); border-color: rgba(255,255,255,0.4); }

.font-sup { font-size: 0.7em; }

/* Input Grid */
.io-grid       { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; margin-bottom: 2rem; min-width: 0; }
.io-column     { display: flex; flex-direction: column; gap: 8px; min-width: 0; }

.column-header    { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; }
.col-title        { font-size: 1rem; color: var(--text-muted); font-family: var(--font-heading); margin: 0; }
.column-actions   { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

.paste-btn { padding: 5px 10px; font-size: 0.8rem; min-height: 40px; }

.file-upload {
    cursor: pointer; font-size: 0.85rem; color: var(--primary-accent);
    display: flex; align-items: center; gap: 5px; border-radius: 4px;
    padding: 2px 4px;
}
.file-upload:hover         { text-decoration: underline; }
.file-upload:focus-visible { outline: 2px solid var(--primary-accent); }

textarea {
    width: 100%; min-height: 280px;
    background: var(--input-bg); border: 1px solid var(--card-border);
    border-radius: 8px; padding: 1rem;
    color: var(--text-main); font-family: var(--font-code); font-size: 0.9rem;
    resize: vertical; outline: none; line-height: 1.5;
    transition: border-color 0.2s, background-color 0.2s;
    scrollbar-width: thin;
    scrollbar-color: var(--scroll-thumb) transparent;
}
textarea:focus         { border-color: var(--primary-accent); }
textarea:focus-visible { outline: none; }

.drop-zone.drag-over textarea { border-color: var(--primary-accent); background: rgba(59,130,246,0.08); }
.drop-zone.drag-over          { outline: 2px dashed var(--primary-accent); outline-offset: 4px; border-radius: 10px; }

/* Text Stats */
.text-stats {
    font-family: var(--font-code); font-size: 0.78rem; color: var(--text-muted);
    padding: 4px 2px; display: flex; gap: 6px; flex-wrap: wrap;
    overflow-wrap: anywhere;
}

/* Results Section */
.results-card {
    background: var(--editor-bg); border: 1px solid var(--card-border);
    border-radius: 12px; padding: 1.5rem; margin-top: 2rem; overflow: hidden;
    transition: background-color 0.2s, border-color 0.2s;
    min-width: 0;
}

.results-header {
    display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 1rem; border-bottom: 1px solid var(--card-border);
    padding-bottom: 10px; flex-wrap: wrap; gap: 8px;
}

.diff-stats    { font-family: var(--font-code); font-size: 0.9rem; color: var(--text-muted); overflow-wrap: anywhere; }
.stat-add      { color: #10b981; }
.stat-del      { color: #ef4444; }

.view-toggle {
    background: var(--toggle-bg); padding: 4px; border-radius: 8px;
    display: inline-flex; align-items: center; flex-wrap: wrap; gap: 3px;
}
.toggle-btn {
    background: transparent; border: none; color: var(--text-muted);
    padding: 6px 14px; border-radius: 6px; cursor: pointer; font-size: 0.85rem;
    min-height: 44px;
}
.toggle-btn.active        { background: var(--primary-accent); color: #fff; }
.toggle-btn:focus-visible { outline: 2px solid var(--primary-accent); }
.nav-btn   { padding: 6px 10px; }
.font-btn  { padding: 6px 10px; font-family: var(--font-body); font-weight: 700; }

.divider-v {
    width: 1px; height: 24px; background: var(--card-border);
    margin: 0 4px; align-self: center;
}

.identical-banner {
    display: flex; align-items: center; gap: 10px;
    background: rgba(16,185,129,0.12); border: 1px solid rgba(16,185,129,0.4);
    color: #059669; border-radius: 8px; padding: 12px 16px;
    margin-bottom: 1rem; font-weight: 600; font-size: 0.95rem;
}
html:not(.light-theme) .identical-banner { color: #10b981; }
.identical-banner i { font-size: 1.1rem; }

.monaco-wrapper {
    width: 100%;
    min-height: 550px;
    height: 65vh;
    max-height: 900px;
    border-radius: 6px;
    overflow: hidden;
    border: 1px solid var(--card-border);
}

.results-card.fullscreen-mode {
    position: fixed; top: 0; left: 0; width: 100vw; height: 100vh;
    margin: 0; border-radius: 0; z-index: 1500;
    display: flex; flex-direction: column;
    padding: 1.5rem; box-sizing: border-box;
}
.results-card.fullscreen-mode .monaco-wrapper {
    flex: 1; height: auto; max-height: none; min-height: 0;
}

.hidden { display: none !important; }

/* Toast */
.toast {
    position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%);
    background: var(--toast-bg); border: 1px solid var(--primary-accent);
    color: var(--text-main); padding: 10px 20px; border-radius: 8px; z-index: 2000;
    font-family: var(--font-body); font-size: 0.9rem; box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    white-space: nowrap; opacity: 0; pointer-events: none; transition: opacity 0.3s;
}
.toast.toast-visible  { opacity: 1; pointer-events: auto; }
.toast.toast-error    { border-color: #ef4444; }
.toast.toast-success  { border-color: #10b981; }
.toast.toast-info     { border-color: var(--primary-accent); }

/* Info & FAQ */
.info-section    { margin-top: 4rem; padding: 0 1rem; }
.info-section h2 { font-family: var(--font-heading); color: var(--text-main); margin-bottom: 2rem; font-size: 1.5rem; text-align: center; }
.info-grid       { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 2rem; margin-bottom: 3rem; }
.info-grid h3    { color: var(--primary-accent); font-family: var(--font-heading); font-size: 1.1rem; margin-bottom: 0.5rem; }
.info-grid i     { margin-right: 8px; }
.info-grid p     { color: var(--text-muted); font-size: 0.95rem; line-height: 1.6; }

/* Semantic FAQ Section */
.faq-container    { margin-top: 2rem; max-width: 900px; margin-left: auto; margin-right: auto; }
.faq-container h2 { font-family: var(--font-heading); color: var(--text-main); margin-bottom: 1.5rem; font-size: 1.5rem; text-align: center; }
.faq-container details {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    margin-bottom: 1rem;
    overflow: hidden;
    transition: border-color 0.2s, background-color 0.2s;
}
.faq-container summary {
    font-family: var(--font-heading);
    font-weight: 600;
    color: var(--primary-accent);
    padding: 1rem 1.2rem;
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1rem;
}
.faq-container summary::-webkit-details-marker { display: none; }

.faq-container .faq-icon {
    display: inline-block;
    color: var(--text-muted);
    transition: transform 0.3s ease;
}
.faq-container details[open] .faq-icon {
    transform: rotate(180deg);
}

.faq-container details p {
    padding: 0 1.2rem 1.2rem;
    margin: 0;
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
    overflow-wrap: break-word; 
}
.faq-container details p strong { color: var(--text-main); }

.faq-list {
    padding: 0 1.2rem 1.2rem 2.5rem;
    margin: 0;
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}
.faq-list li { margin-bottom: 0.5rem; }
.faq-list code {
    background: var(--code-bg);
    color: var(--code-color);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: var(--font-code);
    font-size: 0.85em;
}

footer       { text-align: center; padding: 3rem 0; color: var(--text-muted); font-size: 0.9rem; border-top: 1px solid var(--card-border); margin-top: 3rem; }
footer a     { color: var(--text-main); text-decoration: none; }
footer a:hover { color: var(--primary-accent); }

/* === RESPONSIVE === */
@media (max-width: 900px) {
    .io-grid       { grid-template-columns: 1fr; }
    textarea       { min-height: 200px; }
    .monaco-wrapper { min-height: 420px; height: 55vh; }
}
@media (max-width: 768px) {
    textarea { resize: none; }
}
@media (max-width: 600px) {
    .tool-header, .main-content { padding: 1rem; }
    .tool-container  { padding: 1.5rem 1rem; }
    .logo { text-align: left; }
    .toolbar         { flex-direction: column; align-items: flex-start; gap: 15px; }
    .control-group, .action-group { width: 100%; }
    
    .regex-container, .regex-input { width: 100%; }
    .tooltip-content { left: 0; transform: none; width: 220px; }
    
    select           { width: 100%; margin-bottom: 10px; }
    
    .action-group    { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px; }
    .action-group button { flex: 1 1 calc(50% - 8px); margin: 0; padding: 10px; font-size: 0.85rem; }
    #compareBtn      { flex: 1 1 100%; }
    
    .kbd-hint        { display: none; }
    .results-header  { flex-direction: column; align-items: flex-start; gap: 12px; }
    .view-toggle     { width: 100%; background: transparent; padding: 0; gap: 6px; flex-wrap: wrap; }
    .toggle-btn      { background: var(--toggle-bg); }
    .copy-merged-btn { margin-left: 0; flex: 1; }
    .divider-v       { display: none; }
}
@media (max-width: 480px) {
    .tool-intro h1  { font-size: 1.4rem; }
    .tool-container { padding: 1rem; border-radius: 12px; }
    textarea        { min-height: 140px; font-size: 0.85rem; }
    .monaco-wrapper { min-height: 300px; height: 45vh; }
    .column-actions { flex-wrap: wrap; gap: 6px; }
    .paste-btn      { flex: 1; }
    .back-btn span  { display: none; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration:  0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}

/* Monaco Diff High-Contrast Overrides */
html:not(.light-theme) .monaco-diff-editor .line-delete,
html:not(.light-theme) .monaco-diff-editor .view-overlays .line-delete { background-color: #3a000099 !important; }
html:not(.light-theme) .monaco-diff-editor .line-insert,
html:not(.light-theme) .monaco-diff-editor .view-overlays .line-insert { background-color: #00330099 !important; }
html:not(.light-theme) .monaco-diff-editor .gutter .line-delete { background-color: #4d0000 !important; }
html:not(.light-theme) .monaco-diff-editor .gutter .line-insert { background-color: #004d00 !important; }
html:not(.light-theme) .monaco-editor .cdr.contentDel { background-color: #ff1a1a !important; border-radius: 2px !important; }
html:not(.light-theme) .monaco-editor .cdr.contentIns { background-color: #1a5c35 !important; border-radius: 2px !important; }
html:not(.light-theme) .monaco-diff-editor .char-delete,
html:not(.light-theme) .monaco-diff-editor [class*="char-delete"] { background-color: #ff1a1a !important; border-radius: 2px !important; }
html:not(.light-theme) .monaco-diff-editor .char-insert,
html:not(.light-theme) .monaco-diff-editor [class*="char-insert"] { background-color: #1a5c35 !important; border-radius: 2px !important; }
html:not(.light-theme) .mon-diff-editor .line-delete .view-line span[class^="mtk"] { color: #ffcccc !important; }
html:not(.light-theme) .monaco-diff-editor .line-insert .view-line span[class^="mtk"] { color: #e8ffe8 !important; }
html:not(.light-theme) .monaco-editor .inline-deleted-margin-view-zone { background-color: #4d0000 !important; }
html:not(.light-theme) .monaco-editor .inline-added-margin-view-zone   { background-color: #004d00 !important; }
html:not(.light-theme) .monaco-diff-editor .diagonal-fill {
    background: repeating-linear-gradient(-45deg, transparent, transparent 4px, rgba(255,255,255,0.03) 4px, rgba(255,255,255,0.03) 8px) !important;
}