/* ==========================================================================
   SynthID Shield v2.0 — Modern Deep-Tech / Cyberpunk UI Styles
   ========================================================================== */

:root {
    --bg-base: #080b12;
    --bg-card: rgba(15, 21, 37, 0.75);
    --bg-card-hover: rgba(22, 30, 52, 0.85);
    --card-border: rgba(0, 242, 254, 0.12);
    --card-border-active: rgba(0, 242, 254, 0.45);
    
    --accent-cyan: #00f2fe;
    --accent-purple: #7928ca;
    --accent-magenta: #ff007a;
    --accent-green: #00ff88;
    --accent-amber: #ffb300;
    --accent-red: #ff2a55;

    --text-main: #f0f4fc;
    --text-muted: #8e9bb5;
    --text-dim: #5c6882;

    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-full: 9999px;

    --shadow-glow-cyan: 0 0 25px rgba(0, 242, 254, 0.25);
    --shadow-glow-purple: 0 0 25px rgba(121, 40, 202, 0.25);
    --transition-smooth: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
    background-color: var(--bg-base);
    color: var(--text-main);
    font-family: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
    line-height: 1.5;
}

/* Ambient Background Glows */
.ambient-glow {
    position: fixed;
    border-radius: 50%;
    filter: blur(140px);
    pointer-events: none;
    z-index: 0;
    opacity: 0.28;
    animation: floatGlow 18s ease-in-out infinite alternate;
}

.glow-1 {
    top: -10%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, #00f2fe 0%, #7928ca 80%);
}

.glow-2 {
    bottom: -15%;
    right: -10%;
    width: 700px;
    height: 700px;
    background: radial-gradient(circle, #7928ca 0%, #ff007a 80%);
    animation-delay: -9s;
}

.glow-3 {
    top: 40%;
    left: 45%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(0, 255, 136, 0.4) 0%, transparent 70%);
}

@keyframes floatGlow {
    0% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(40px, 30px) scale(1.08); }
    100% { transform: translate(-30px, -20px) scale(0.95); }
}

/* Layout Container */
.app-container {
    position: relative;
    z-index: 1;
    max-width: 1380px;
    margin: 0 auto;
    padding: 24px 32px 48px;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--card-border);
    margin-bottom: 28px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 16px;
}

.brand-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-md);
    background: rgba(0, 242, 254, 0.08);
    border: 1px solid var(--card-border-active);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-glow-cyan);
}

.brand-text h1 {
    font-size: 26px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.gradient-text {
    background: linear-gradient(135deg, #00f2fe 0%, #4facfe 50%, #9b51e0 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.tagline {
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 400;
}

.header-badges {
    display: flex;
    gap: 12px;
    align-items: center;
}

.status-badge {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 7px 14px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 600;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(8px);
}

.live-status {
    color: var(--accent-green);
    border-color: rgba(0, 255, 136, 0.3);
}

.pulse-dot {
    width: 8px;
    height: 8px;
    background-color: var(--accent-green);
    border-radius: 50%;
    box-shadow: 0 0 10px var(--accent-green);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { transform: scale(0.95); opacity: 0.8; }
    50% { transform: scale(1.25); opacity: 1; }
    100% { transform: scale(0.95); opacity: 0.8; }
}

.tech-badge {
    color: var(--accent-cyan);
    border-color: rgba(0, 242, 254, 0.3);
}

/* Tabs */
.nav-tabs {
    display: flex;
    gap: 10px;
    background: rgba(12, 17, 30, 0.6);
    padding: 6px;
    border-radius: var(--radius-md);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(12px);
    margin-bottom: 28px;
    width: fit-content;
}

.tab-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 500;
    font-family: inherit;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition-smooth);
}

.tab-btn:hover {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.04);
}

.tab-btn.active {
    color: #000;
    background: linear-gradient(135deg, #00f2fe 0%, #4facfe 100%);
    font-weight: 600;
    box-shadow: 0 4px 15px rgba(0, 242, 254, 0.3);
}

/* Tab Contents */
.tab-content {
    display: none;
    animation: fadeIn 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Grid Layout */
.grid-layout {
    display: grid;
    grid-template-columns: 460px 1fr;
    gap: 28px;
    align-items: start;
}

@media (max-width: 1024px) {
    .grid-layout {
        grid-template-columns: 1fr;
    }
}

/* Cards */
.card {
    background: var(--bg-card);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: 24px;
    backdrop-filter: blur(20px);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4);
    position: relative;
    overflow: hidden;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.card-header h2 {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: -0.3px;
}

.card-header h3 {
    font-size: 16px;
    font-weight: 600;
}

.badge-subtle {
    font-size: 11px;
    padding: 4px 10px;
    border-radius: var(--radius-full);
    background: rgba(255, 255, 255, 0.06);
    color: var(--text-muted);
    font-weight: 500;
}

.badge-subtle.green {
    background: rgba(0, 255, 136, 0.12);
    color: var(--accent-green);
}

.badge-subtle.red {
    background: rgba(255, 42, 85, 0.12);
    color: var(--accent-red);
}

/* Dropzone */
.dropzone {
    border: 2px dashed var(--card-border);
    border-radius: var(--radius-md);
    background: rgba(0, 242, 254, 0.02);
    padding: 36px 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition-smooth);
    margin-bottom: 22px;
}

.dropzone:hover, .dropzone.dragover {
    border-color: var(--accent-cyan);
    background: rgba(0, 242, 254, 0.06);
    box-shadow: var(--shadow-glow-cyan);
}

.drop-icon {
    color: var(--accent-cyan);
    margin-bottom: 12px;
}

.drop-title {
    font-size: 15px;
    font-weight: 500;
    margin-bottom: 6px;
}

.accent-link {
    color: var(--accent-cyan);
    text-decoration: underline;
}

.drop-subtitle {
    font-size: 12px;
    color: var(--text-dim);
}

/* Selected File Card */
.file-preview-card {
    display: flex;
    align-items: center;
    gap: 14px;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--card-border-active);
    padding: 12px 16px;
    border-radius: var(--radius-md);
    margin-bottom: 20px;
}

.file-icon {
    font-size: 24px;
}

.file-meta {
    flex: 1;
    overflow: hidden;
}

.file-name {
    display: block;
    font-size: 14px;
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.file-size {
    font-size: 12px;
    color: var(--text-muted);
}

.btn-icon {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 16px;
    cursor: pointer;
    padding: 6px;
    border-radius: var(--radius-sm);
    transition: var(--transition-smooth);
}

.btn-icon:hover {
    color: var(--accent-red);
    background: rgba(255, 42, 85, 0.1);
}

/* Mode Selection Cards */
.section-title {
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
    margin-bottom: 12px;
}

.mode-grid {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 22px;
}

.mode-card {
    display: block;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    padding: 14px 16px;
    cursor: pointer;
    transition: var(--transition-smooth);
    position: relative;
}

.mode-card:hover {
    background: var(--bg-card-hover);
    border-color: rgba(0, 242, 254, 0.3);
}

.mode-card input[type="radio"],
.mode-card input[type="checkbox"] {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.mode-card.active {
    background: rgba(0, 242, 254, 0.06);
    border-color: var(--accent-cyan);
    box-shadow: 0 0 20px rgba(0, 242, 254, 0.15);
}

.mode-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 4px;
    padding-right: 32px;
}

.mode-name {
    font-size: 14px;
    font-weight: 600;
}

.mode-badge {
    font-size: 11px;
    font-weight: 600;
    padding: 3px 8px;
    border-radius: var(--radius-full);
}

.mode-badge.green { background: rgba(0, 255, 136, 0.15); color: var(--accent-green); }
.mode-badge.purple { background: rgba(121, 40, 202, 0.2); color: #b76eff; }
.mode-badge.cyan { background: rgba(0, 242, 254, 0.15); color: var(--accent-cyan); }
.mode-badge.amber { background: rgba(255, 179, 0, 0.15); color: var(--accent-amber); }

.mode-desc {
    font-size: 12px;
    color: var(--text-muted);
    line-height: 1.4;
}

/* Options Group */
.options-group {
    display: flex;
    flex-direction: column;
    gap: 14px;
    margin-bottom: 24px;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 13px;
    color: var(--text-muted);
    cursor: pointer;
}

.checkbox-label input[type="checkbox"] {
    display: none;
}

.checkbox-custom {
    width: 18px;
    height: 18px;
    border-radius: 4px;
    border: 1px solid var(--card-border-active);
    background: rgba(255, 255, 255, 0.04);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-smooth);
}

.checkbox-label input[type="checkbox"]:checked + .checkbox-custom {
    background: var(--accent-cyan);
    border-color: var(--accent-cyan);
}

.checkbox-label input[type="checkbox"]:checked + .checkbox-custom::after {
    content: "✓";
    color: #000;
    font-size: 12px;
    font-weight: 800;
}

.select-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    font-size: 13px;
    color: var(--text-muted);
}

.custom-select {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--card-border);
    color: var(--text-main);
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 13px;
    outline: none;
    cursor: pointer;
    transition: var(--transition-smooth);
}

.custom-select:focus {
    border-color: var(--accent-cyan);
}

.custom-select option {
    background: #101625;
    color: #fff;
}

/* Buttons */
.btn {
    width: 100%;
    padding: 14px;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    transition: var(--transition-smooth);
}

.btn-primary {
    background: linear-gradient(135deg, #00f2fe 0%, #4facfe 100%);
    color: #000;
    box-shadow: 0 4px 20px rgba(0, 242, 254, 0.35);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 28px rgba(0, 242, 254, 0.5);
}

.btn-primary:disabled {
    opacity: 0.45;
    cursor: not-allowed;
    box-shadow: none;
}

.btn-sm {
    padding: 8px 14px;
    font-size: 13px;
    font-weight: 500;
    font-family: inherit;
    border-radius: var(--radius-sm);
    border: 1px solid var(--card-border);
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-main);
    display: inline-flex;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    transition: var(--transition-smooth);
}

.btn-sm:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--card-border-active);
}

.btn-accent {
    background: linear-gradient(135deg, #00f2fe 0%, #4facfe 100%);
    color: #000;
    border: none;
    font-weight: 600;
}

.btn-accent:hover {
    box-shadow: 0 0 15px rgba(0, 242, 254, 0.4);
}

/* Spinner */
.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid rgba(0, 0, 0, 0.2);
    border-top-color: #000;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Results Panel & Empty State */
.result-panel {
    display: flex;
    flex-direction: column;
    min-height: 580px;
}

.empty-state {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}

.empty-icon {
    color: var(--text-dim);
    margin-bottom: 16px;
}

.empty-state h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: 8px;
}

.empty-state p {
    font-size: 14px;
    max-width: 360px;
    line-height: 1.5;
}

/* Before/After Image Comparison Slider */
.comparison-wrapper {
    position: relative;
    width: 100%;
    border-radius: var(--radius-md);
    overflow: hidden;
    background: #000;
    margin-bottom: 22px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.5);
}

.comparison-slider {
    position: relative;
    width: 100%;
    height: 480px;
    overflow: hidden;
    user-select: none;
    cursor: col-resize;
}

.comp-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
    background-color: #05070d;
}

.comp-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    clip-path: polygon(0 0, 50% 0, 50% 100%, 0 100%);
    pointer-events: none;
}

.comp-badge {
    position: absolute;
    bottom: 14px;
    padding: 5px 12px;
    border-radius: var(--radius-full);
    font-size: 11px;
    font-weight: 600;
    backdrop-filter: blur(8px);
    z-index: 5;
}

.badge-before {
    left: 14px;
    background: rgba(255, 42, 85, 0.3);
    border: 1px solid var(--accent-red);
    color: #ff99aa;
}

.badge-after {
    right: 14px;
    background: rgba(0, 255, 136, 0.3);
    border: 1px solid var(--accent-green);
    color: #99ffd5;
}

.comp-handle {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 50%;
    width: 4px;
    background: var(--accent-cyan);
    box-shadow: 0 0 12px var(--accent-cyan);
    z-index: 10;
    transform: translateX(-50%);
    cursor: col-resize;
}

.handle-line {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 1px;
    width: 2px;
    background: #fff;
}

.handle-circle {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background: #000;
    border: 2px solid var(--accent-cyan);
    box-shadow: var(--shadow-glow-cyan);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-cyan);
}

/* Difference Heatmap Overlay */
.diff-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #05070d;
    z-index: 20;
    display: flex;
    flex-direction: column;
}

.diff-img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.diff-legend {
    position: absolute;
    bottom: 14px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 16px;
    background: rgba(10, 14, 25, 0.85);
    border: 1px solid var(--card-border);
    padding: 6px 16px;
    border-radius: var(--radius-full);
    font-size: 11px;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
}

.legend-color {
    width: 12px;
    height: 12px;
    border-radius: 2px;
}

/* Metrics Row */
.metrics-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    margin-bottom: 20px;
}

.metric-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    padding: 14px;
    display: flex;
    flex-direction: column;
}

.metric-label {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.metric-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 2px;
}

.metric-value.green { color: var(--accent-green); }
.metric-value.cyan { color: var(--accent-cyan); }

.metric-hint {
    font-size: 11px;
    color: var(--text-dim);
}

/* Audit Details */
.audit-details {
    background: rgba(0, 0, 0, 0.25);
    border-radius: var(--radius-md);
    padding: 16px;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.audit-details h4 {
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text-muted);
}

.audit-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.audit-list li {
    font-size: 13px;
    display: flex;
    align-items: flex-start;
    gap: 8px;
    line-height: 1.4;
}

/* 2D FFT Spectral Radar Tab */
.spectral-layout {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.spectral-intro-card p {
    font-size: 14px;
    color: var(--text-muted);
    margin-top: 8px;
    line-height: 1.6;
}

.fft-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.fft-card {
    display: flex;
    flex-direction: column;
}

.fft-img-wrap {
    width: 100%;
    height: 380px;
    background: #05070d;
    border-radius: var(--radius-md);
    overflow: hidden;
    margin-bottom: 12px;
    border: 1px solid var(--card-border);
}

.fft-img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.fft-caption {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.5;
}

/* SynthID-Text Tab */
.custom-textarea {
    width: 100%;
    height: 280px;
    background: rgba(10, 14, 25, 0.6);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    color: var(--text-main);
    padding: 16px;
    font-family: inherit;
    font-size: 14px;
    line-height: 1.6;
    resize: none;
    outline: none;
    transition: var(--transition-smooth);
    margin-bottom: 16px;
}

.custom-textarea:focus {
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-glow-cyan);
}

.readonly-textarea {
    background: rgba(10, 14, 25, 0.3);
    border-color: rgba(255, 255, 255, 0.06);
}

.text-controls-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

.intensity-group {
    display: flex;
    align-items: center;
    gap: 8px;
}

.control-label {
    font-size: 13px;
    color: var(--text-muted);
}

.radio-tag {
    cursor: pointer;
    font-size: 12px;
    padding: 6px 12px;
    border-radius: var(--radius-full);
    border: 1px solid var(--card-border);
    background: rgba(255, 255, 255, 0.03);
    color: var(--text-muted);
    transition: var(--transition-smooth);
}

.radio-tag input {
    display: none;
}

.radio-tag.active {
    background: rgba(0, 242, 254, 0.15);
    border-color: var(--accent-cyan);
    color: var(--accent-cyan);
    font-weight: 600;
}

.text-metrics-bar {
    display: flex;
    gap: 20px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-sm);
    padding: 10px 16px;
    margin-bottom: 16px;
}

.t-metric {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
}

.t-label { color: var(--text-muted); }
.t-val { font-family: 'JetBrains Mono', monospace; font-weight: 700; }
.t-val.green { color: var(--accent-green); }
.t-val.cyan { color: var(--accent-cyan); }
.t-sub { font-size: 11px; color: var(--text-dim); }

/* CLI Tab */
.cli-doc-card h3 {
    margin-top: 24px;
    margin-bottom: 10px;
    font-size: 15px;
    color: var(--accent-cyan);
}

.code-block {
    background: #05070d;
    border: 1px solid var(--card-border);
    border-radius: var(--radius-md);
    padding: 18px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    color: #9cdcfe;
    overflow-x: auto;
    line-height: 1.6;
}

/* Footer */
.footer {
    margin-top: auto;
    padding-top: 36px;
    text-align: center;
    font-size: 12px;
    color: var(--text-dim);
}

/* Toast */
.toast {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: rgba(16, 22, 38, 0.95);
    border: 1px solid var(--accent-cyan);
    box-shadow: var(--shadow-glow-cyan);
    color: var(--text-main);
    padding: 12px 20px;
    border-radius: var(--radius-md);
    font-size: 14px;
    z-index: 1000;
    opacity: 0;
    transform: translateY(20px);
    transition: var(--transition-smooth);
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}


/* Select All button */
.section-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.btn-select-all {
    background: rgba(0, 242, 254, 0.08);
    border: 1px solid rgba(0, 242, 254, 0.3);
    color: var(--accent-cyan);
    font-size: 12px;
    font-weight: 600;
    padding: 5px 14px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition-smooth);
    font-family: var(--font-main);
}

.btn-select-all:hover {
    background: rgba(0, 242, 254, 0.15);
    border-color: var(--accent-cyan);
}

.btn-select-all.active {
    background: var(--accent-cyan);
    color: var(--bg-deep);
}

/* Checkbox indicator on mode cards */
.mode-card::before {
    content: '';
    position: absolute;
    top: 16px;
    right: 16px;
    width: 20px;
    height: 20px;
    border-radius: 5px;
    border: 2px solid rgba(255, 255, 255, 0.25);
    background: rgba(0, 0, 0, 0.25);
    transition: var(--transition-smooth);
    box-sizing: border-box;
    pointer-events: none;
}

.mode-card.active::before {
    background: var(--accent-cyan);
    border-color: var(--accent-cyan);
    box-shadow: 0 0 10px rgba(0, 242, 254, 0.4);
}

.mode-card.active::after {
    content: '✓';
    position: absolute;
    top: 16px;
    right: 20px;
    font-size: 14px;
    font-weight: 800;
    color: #0b0f19;
    z-index: 1;
    pointer-events: none;
    line-height: 18px;
}

/* Multi-select hint */
.mode-hint {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: -6px;
    margin-bottom: 14px;
    opacity: 0.7;
}