/* ═══════════════════════════════════════════════
   shared-base.css — Shared styles for all a9l.im sites
   ═══════════════════════════════════════════════ */

/* ─── Reset ─── */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

/* ─── Layout Tokens ─── */
:root {
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-pill: 9999px;

    --toolbar-h: 52px;
    --panel-w: 350px;

    --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ─── Body Base ─── */
body {
    background: var(--bg-canvas);
    color: var(--text);
    font-family: var(--font-body);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background-color 0.5s var(--ease-out), color 0.4s var(--ease-out);
}

/* ─── Glass Panel ─── */
.glass {
    background: var(--bg-panel);
    backdrop-filter: blur(24px) saturate(1.3);
    -webkit-backdrop-filter: blur(24px) saturate(1.3);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-md);
}

/* ─── Tool Buttons ─── */
.tool-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    background: transparent;
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    cursor: pointer;
    padding: 0;
    flex-shrink: 0;
    outline: none;
    -webkit-appearance: none;
    transition: color 0.2s, background 0.2s, border-color 0.2s, opacity 0.2s, box-shadow 0.2s;
}

.tool-btn svg {
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}

.tool-btn:hover {
    color: var(--text);
    background: var(--bg-hover);
    border-color: var(--border);
}

.tool-btn:active {
    background: var(--border-strong);
    transform: scale(0.94);
    transition-duration: 0.05s;
}

.tool-btn:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.tool-btn.active {
    color: var(--accent);
    background: var(--accent-subtle);
    border-color: var(--accent-glow);
}


.tool-btn:disabled,
.tool-btn[disabled] {
    opacity: 0.22;
    cursor: default;
    pointer-events: none;
}

/* ─── Speed Button ─── */
.speed-btn {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 600;
    min-width: 34px;
}

/* ─── Keyframes ─── */
@keyframes slideDown {
    from { opacity: 0; transform: translateY(-16px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-24px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(24px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes paletteEnter {
    from { opacity: 0; transform: translateX(-50%) translateY(12px); }
    to { opacity: 1; transform: translateX(-50%) translateY(0); }
}

@keyframes introBgPulse {
    0% { opacity: 0.5; transform: scale(1); }
    100% { opacity: 1; transform: scale(1.05); }
}

@keyframes introContentIn {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

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

/* ─── Intro Screen ─── */
#intro-screen {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-canvas);
    overflow: hidden;
    transition: opacity 0.85s var(--ease-out), transform 0.85s var(--ease-out);
}

#intro-screen.hidden {
    opacity: 0;
    transform: scale(1.02);
    pointer-events: none;
}

.intro-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 25% 35%, var(--intro-warm) 0%, transparent 55%),
        radial-gradient(ellipse at 75% 65%, var(--intro-cool) 0%, transparent 45%);
    animation: introBgPulse 10s ease-in-out infinite alternate;
}

.intro-content {
    text-align: center;
    max-width: 620px;
    padding: 2.5rem;
    position: relative;
    z-index: 1;
    animation: introContentIn 1s var(--ease-out) 0.15s both;
}

.intro-overline {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 500;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 1.2rem;
}

.intro-title {
    font-family: var(--font-display);
    font-size: clamp(3.2rem, 8vw, 5.5rem);
    font-weight: 400;
    color: var(--text);
    line-height: 0.92;
    letter-spacing: -0.03em;
    margin-bottom: 1.5rem;
}

.intro-subtitle {
    font-size: 0.55em;
    font-weight: 300;
    display: block;
    letter-spacing: 0.04em;
}

.intro-desc {
    font-family: var(--font-body);
    color: var(--text-secondary);
    font-size: clamp(0.88rem, 1.4vw, 1rem);
    line-height: 1.7;
    margin-bottom: 2.8rem;
    font-weight: 400;
}

.intro-cards {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
    justify-content: center;
    flex-wrap: wrap;
}

.intro-card {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.7rem 1rem;
    background: var(--bg-hover);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    text-align: left;
    transition: background 0.25s;
    animation: fadeUp 0.6s var(--ease-out) both;
}

.intro-card:nth-child(1) { animation-delay: 0.5s; }
.intro-card:nth-child(2) { animation-delay: 0.62s; }
.intro-card:nth-child(3) { animation-delay: 0.74s; }

.intro-card:hover {
    background: var(--border-strong);
}

.intro-card-icon {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
    background: var(--accent-subtle);
    color: var(--accent);
    flex-shrink: 0;
}

.intro-card-text {
    display: flex;
    flex-direction: column;
}

.intro-card-text strong {
    color: var(--text);
    font-size: 0.82rem;
    font-weight: 600;
    line-height: 1.2;
}

.intro-card-text span {
    color: var(--text-muted);
    font-size: 0.72rem;
    line-height: 1.4;
}

#intro-start {
    font-family: var(--font-body);
    font-size: 0.92rem;
    font-weight: 500;
    color: #FDFBF5;
    background: var(--accent);
    border: none;
    border-radius: var(--radius-pill);
    padding: 0.8rem 2.8rem;
    cursor: pointer;
    letter-spacing: 0.02em;
    transition: all 0.3s var(--ease-out);
    box-shadow: 0 0 40px var(--accent-glow), 0 0 80px var(--intro-warm);
    animation: fadeUp 0.6s var(--ease-out) 0.9s both;
}

#intro-start:hover {
    background: var(--accent-light);
    transform: translateY(-2px);
    box-shadow: 0 0 50px var(--accent-glow), 0 0 100px var(--intro-warm-hover);
}

#intro-start:active {
    transform: translateY(0);
    box-shadow: 0 0 30px var(--accent-glow);
}

/* ─── Sidebar Patterns ─── */
.group-label {
    font-family: var(--font-body);
    font-weight: 600;
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--text-muted);
    margin-bottom: 0.65rem;
    padding-bottom: 0.4rem;
    border-bottom: 1px solid var(--border);
}

.stats-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 16px 12px;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
}

.stats-title {
    font-family: var(--font-body);
    font-size: 0.82rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.10em;
    color: var(--text);
}

.stat-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 6px 8px;
    margin-bottom: 1px;
    border-radius: 6px;
    transition: background 0.15s ease;
}

.stat-row:hover {
    background: var(--bg-hover);
}

.stat-label {
    font-size: 0.78rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.stat-value {
    font-family: var(--font-mono);
    font-weight: 600;
    font-size: 0.78rem;
    color: var(--text);
    min-width: 2em;
    text-align: right;
    display: inline-block;
    font-variant-numeric: tabular-nums;
}

.stat-group {
    margin-bottom: 0.6rem;
}
.stat-group:last-child {
    margin-bottom: 0;
}

/* ─── Tab System ─── */
.tabs-wrap {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    animation: fadeUp 0.4s ease 0.15s both;
}

.tab-bar {
    display: flex;
    gap: 0;
    border-bottom: 1px solid var(--border);
    padding: 0 16px;
    flex-shrink: 0;
    position: sticky;
    top: 0;
    z-index: 5;
}

.tab-btn {
    flex: 1;
    padding: 0.6rem 0.4rem 0.5rem;
    background: transparent;
    border: none;
    border-bottom: 2px solid transparent;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: clamp(0.62rem, 0.95vw, 0.7rem);
    color: var(--text-muted);
    cursor: pointer;
    transition: all 0.28s ease;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    text-align: center;
}

.tab-btn:hover {
    color: var(--text-secondary);
}

.tab-btn.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

.tab-panels {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
}

.tab-panel {
    display: none;
    padding: 12px 16px;
}

.tab-panel.active {
    display: block;
    animation: fadeIn 0.2s ease both;
}

/* ─── Sim Layout Components ─── */

/* Floating toolbar */
.sim-toolbar {
    position: fixed;
    top: 12px;
    left: 12px;
    right: 12px;
    height: var(--toolbar-h);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 12px 0 20px;
    gap: 1rem;
    border-radius: var(--radius-lg);
    opacity: 0;
    pointer-events: none;
    transition: background-color 0.4s var(--ease-out), border-color 0.3s var(--ease-out);
}

.app-ready .sim-toolbar {
    animation: slideDown 0.55s var(--ease-out) 0.08s both;
    pointer-events: auto;
}

/* Toolbar right-side button group */
.sim-toolbar-actions {
    display: flex;
    align-items: center;
    gap: 3px;
    flex-shrink: 0;
}

/* Vertical separator */
.tool-sep {
    width: 1px;
    height: 18px;
    background: var(--border-strong);
    margin: 0 4px;
    flex-shrink: 0;
    opacity: 0.6;
}

/* Home logo link */
.sim-home {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.sim-home img {
    height: 28px;
    width: auto;
    transition: opacity 0.2s var(--ease-out);
}

.sim-home:hover img {
    opacity: 0.7;
}

/* Ensure brand wrapper is a flex row when logo is present */
.sim-toolbar :has(> .sim-home) {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Brand title with accent gradient */
.sim-brand {
    font-family: var(--font-display);
    font-size: clamp(1.1rem, 2vw, 1.5rem);
    font-weight: 400;
    color: var(--text);
    letter-spacing: -0.025em;
    line-height: 1.1;
    white-space: nowrap;
}

.sim-brand em {
    font-style: italic;
    background: linear-gradient(135deg, var(--accent-light) 20%, var(--accent) 80%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Right-side floating panel */
.sim-panel {
    position: fixed;
    top: calc(12px + var(--toolbar-h) + 12px);
    right: 12px;
    bottom: 12px;
    width: var(--panel-w);
    z-index: 90;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    transform: translateX(calc(100% + 24px));
    transition: background-color 0.4s, border-color 0.3s;
}

.app-ready .sim-panel {
    transition: transform 0.55s var(--ease-out), background-color 0.4s, border-color 0.3s;
}

.sim-panel.open {
    transform: translateX(0);
}

/* Floating bottom pill */
.sim-bar {
    position: fixed;
    bottom: 12px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 4px 8px;
    border-radius: var(--radius-pill);
    z-index: 100;
    opacity: 0;
    pointer-events: none;
    transition: background-color 0.4s var(--ease-out), border-color 0.3s var(--ease-out);
}

.app-ready .sim-bar {
    animation: paletteEnter 0.5s var(--ease-out) 0.2s both;
    pointer-events: auto;
}

/* Floating left control stack */
.sim-controls {
    position: absolute;
    bottom: 12px;
    left: 16px;
    display: flex;
    flex-direction: column;
    gap: 1px;
    border-radius: var(--radius-md);
    padding: 3px;
    z-index: 20;
    align-items: center;
    font-variant-numeric: tabular-nums;
    opacity: 0;
    pointer-events: none;
    transition: background-color 0.4s var(--ease-out), border-color 0.3s var(--ease-out);
}

.app-ready .sim-controls {
    animation: slideInLeft 0.4s var(--ease-out) 0.35s both;
    pointer-events: auto;
}

/* ─── Small Utilities ─── */

/* Zoom percentage text */
.zoom-level {
    font-family: var(--font-mono);
    font-size: 0.56rem;
    font-weight: 500;
    color: var(--text-muted);
    padding: 0 4px;
    text-align: center;
    min-width: 34px;
    font-variant-numeric: tabular-nums;
    user-select: none;
    line-height: 1.5;
    letter-spacing: -0.02em;
}

/* Horizontal control separator */
.ctrl-sep {
    width: 20px;
    height: 1px;
    background: var(--border);
    margin: 2px auto;
}

/* Thin scrollbar */
.scrollbar-thin {
    scrollbar-width: thin;
    scrollbar-color: var(--border-strong) transparent;
}

.scrollbar-thin::-webkit-scrollbar { width: 4px; }
.scrollbar-thin::-webkit-scrollbar-track { background: transparent; }
.scrollbar-thin::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 4px; }

/* Hint text box */
.panel-hint {
    color: var(--text-muted);
    font-size: clamp(0.62rem, 0.9vw, 0.7rem);
    line-height: 1.5;
    font-style: italic;
    margin-top: 0.5rem;
    padding: 0.4rem 0.55rem;
    border-radius: var(--radius-sm);
    background: var(--accent-subtle);
    border: 1px solid var(--accent-glow);
}

.hidden {
    display: none !important;
}

/* ─── Global Focus & Selection ─── */
::selection {
    background: var(--accent-glow);
    color: var(--text);
}

:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* ─── Sheet Handle (mobile bottom sheet drag handle) ─── */
.sheet-handle {
    display: none;
}

/* ─── Responsive: Primary Mobile ─── */
@media (max-width: 900px) {
    :root {
        --toolbar-h: 48px;
    }

    .sim-toolbar {
        top: 8px;
        left: 8px;
        right: 8px;
        padding: 0 8px 0 16px;
    }

    .sim-brand {
        font-size: 1.05rem;
    }

    .tool-btn svg {
        width: 16px;
        height: 16px;
    }

    .tool-sep {
        height: 14px;
        margin: 0 2px;
    }

    /* Bottom sheet touch optimizations */
    .sim-panel {
        will-change: transform;
        overscroll-behavior: contain;
    }

    .tabs-wrap { min-height: auto; }
    .tab-bar { position: static; }
    .tab-panels { max-height: calc(60vh - 120px); }

    /* Sheet handle — visible on mobile */
    .sheet-handle {
        display: flex;
        justify-content: center;
        padding: 12px 0 8px;
        cursor: grab;
        flex-shrink: 0;
        touch-action: none;
    }

    .sheet-handle::after {
        content: '';
        width: 40px;
        height: 4px;
        background: var(--border-strong);
        border-radius: 2px;
        transition: width 0.2s var(--ease-out), background 0.2s;
    }

    .sheet-handle:active {
        cursor: grabbing;
    }

    .sheet-handle:active::after {
        width: 48px;
        background: var(--text-muted);
    }
}

/* ─── Responsive: Small Phone ─── */
@media (max-width: 600px) {
    .sim-brand {
        font-size: 0.92rem;
    }

    .tool-btn {
        width: 32px;
        height: 32px;
    }

    .sim-toolbar-actions {
        gap: 2px;
    }

    .tool-sep {
        margin: 0 1px;
    }
}

/* ─── Responsive: Minimal UI ─── */
@media (max-width: 440px) {
    .hide-sm {
        display: none !important;
    }

    .sim-brand {
        display: none;
    }

    .sim-toolbar-actions {
        gap: 1px;
    }
}

/* ─── Toast Notifications ─── */
#toast-container {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 9999;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    pointer-events: none;
}

.toast {
    padding: 8px 24px;
    border-radius: var(--radius-pill);
    background: var(--bg-elevated);
    color: var(--text);
    font: 500 0.82rem var(--font-body);
    box-shadow: var(--shadow-md);
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 0.3s var(--ease-out), transform 0.3s var(--ease-out);
    pointer-events: auto;
}

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

/* ─── Accessibility ─── */
.skip-link {
    position: fixed;
    top: -100%;
    left: 16px;
    z-index: 10000;
    padding: 8px 16px;
    background: var(--accent);
    color: #FDFBF5;
    font: 500 0.85rem var(--font-body);
    border-radius: var(--radius-sm);
    text-decoration: none;
    transition: top 0.2s var(--ease-out);
}

.skip-link:focus {
    top: 16px;
}

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

/* ─── Info Tip Triggers ─── */
.info-trigger {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    border: 1px solid var(--border-strong);
    background: transparent;
    color: var(--text-muted);
    font-size: 0.6rem;
    font-weight: 700;
    font-family: var(--font-body);
    cursor: help;
    padding: 0;
    margin-left: 4px;
    flex-shrink: 0;
    line-height: 1;
    vertical-align: middle;
    transition: color 0.15s, border-color 0.15s, background 0.15s;
}

.info-trigger:hover,
.info-trigger:focus-visible {
    color: var(--accent);
    border-color: var(--accent);
    background: var(--accent-subtle);
}

/* ─── Sim Tooltip (cursor-following) ─── */
.sim-tooltip {
    position: fixed;
    z-index: 200;
    padding: 6px 10px;
    border-radius: var(--radius-sm);
    background: var(--bg-panel-solid);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    font: 500 0.72rem / 1.55 var(--font-mono);
    color: var(--text);
    pointer-events: none;
    white-space: nowrap;
    font-variant-numeric: tabular-nums;
    opacity: 0;
    transform: translateY(4px);
    transition: opacity 0.12s ease, transform 0.12s ease;
}

.sim-tooltip.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ─── Info Tip Popovers ─── */
.info-popover {
    position: fixed;
    z-index: 9000;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    background: var(--bg-panel-solid);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    font-family: var(--font-body);
    font-size: 0.78rem;
    line-height: 1.55;
    color: var(--text);
    opacity: 0;
    transform: translateY(4px);
    transition: opacity 0.18s var(--ease-out), transform 0.18s var(--ease-out);
    pointer-events: none;
}

.info-popover-below {
    transform: translateY(-4px);
}

.info-popover-visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.info-popover-title {
    font-weight: 600;
    font-size: 0.82rem;
    margin-bottom: 4px;
    color: var(--text);
}

.info-popover-body {
    color: var(--text-secondary);
}

.info-popover-body .katex {
    font-size: 1.05em;
}

.info-popover-body .katex-display {
    overflow-x: auto;
    margin: 0.4em 0;
}

.info-popover-close {
    position: absolute;
    top: 6px;
    right: 6px;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
    padding: 0;
    border-radius: 50%;
    transition: color 0.15s, background 0.15s;
}

.info-popover-close:hover {
    color: var(--text);
    background: var(--bg-hover);
}

/* ─── Shortcut Overlay ─── */
.shortcut-overlay {
    position: fixed;
    inset: 0;
    z-index: 9500;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--backdrop);
    opacity: 0;
    transition: opacity 0.2s var(--ease-out);
}

.shortcut-overlay-visible {
    opacity: 1;
}

.shortcut-content {
    background: var(--bg-panel-solid);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 24px 28px;
    max-width: 420px;
    width: 90vw;
    max-height: 80vh;
    overflow-y: auto;
}

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

.shortcut-header h2 {
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
    margin: 0;
}

.shortcut-group {
    margin-bottom: 16px;
}

.shortcut-group:last-child {
    margin-bottom: 0;
}

.shortcut-group-label {
    font-family: var(--font-body);
    font-weight: 600;
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--text-muted);
    margin-bottom: 8px;
    padding-bottom: 4px;
    border-bottom: 1px solid var(--border);
}

.shortcut-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 5px 0;
}

.shortcut-label {
    font-size: 0.82rem;
    color: var(--text-secondary);
}

.shortcut-key {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 4px;
    border: 1px solid var(--border-strong);
    background: var(--bg-hover);
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--text);
    min-width: 24px;
    text-align: center;
    white-space: nowrap;
}

/* ─── Control Rows ─── */
.ctrl-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.3rem 0;
}

.ctrl-row > label {
    font-size: 0.78rem;
    color: var(--text);
    font-weight: 400;
    cursor: pointer;
}

.ctrl-sub { padding-left: 20px; }
.ctrl-sub > label { font-size: 0.72rem; color: var(--text-secondary); }

.ctrl-disabled { opacity: 0.4; pointer-events: none; }

.ctrl-group {
    margin-bottom: 0.7rem;
}
.ctrl-group:last-child { margin-bottom: 0; }

.panel-section {
    margin-bottom: 0.7rem;
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.panel-section:last-of-type { margin-bottom: 0; }

.stat-sub { padding-left: 20px; }
.stat-sub .stat-label { font-size: 0.72rem; color: var(--text-muted); }
.stat-sub .stat-value { font-size: 0.72rem; color: var(--text-secondary); }

.ctrl-row.locked { opacity: 0.4; pointer-events: none; }

/* ─── Select Dropdowns ─── */
.sim-select {
    width: 100%;
    padding: 6px 10px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: var(--bg-panel);
    color: var(--text);
    font-family: var(--font-body);
    font-size: 0.82rem;
}

/* ─── Form Controls ─── */

/* Slider value display */
.slider-value {
    font-family: var(--font-mono);
    color: var(--text);
    font-weight: 600;
    font-size: 0.78rem;
    font-variant-numeric: tabular-nums;
}

/* Range sliders */
input[type=range] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    width: 100%;
    background: transparent;
    cursor: pointer;
    height: 20px;
}

input[type=range]::-webkit-slider-runnable-track {
    width: 100%;
    height: 2px;
    background: linear-gradient(to right, var(--slider-color, var(--accent)) var(--slider-fill, 0%), var(--slider-track) var(--slider-fill, 0%));
    border-radius: 1px;
}

input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 16px;
    width: 16px;
    border-radius: 50%;
    background: var(--slider-color, var(--accent));
    margin-top: -7px;
    border: none;
    transition: box-shadow 180ms var(--ease-in-out), transform 180ms var(--ease-in-out);
}

input[type=range]:focus::-webkit-slider-thumb {
    box-shadow: 0 0 0 4px var(--accent-subtle);
}

input[type=range]:active::-webkit-slider-thumb {
    transform: scale(1.15);
}

input[type=range]::-moz-range-track {
    width: 100%;
    height: 2px;
    background: var(--slider-track);
    border-radius: 1px;
    border: none;
}

input[type=range]::-moz-range-progress {
    height: 2px;
    background: var(--slider-color, var(--accent));
    border-radius: 1px;
}

input[type=range]::-moz-range-thumb {
    height: 16px;
    width: 16px;
    border-radius: 50%;
    background: var(--slider-color, var(--accent));
    border: none;
}

/* Segmented control (mode toggles) */
.mode-toggles {
    display: grid;
    grid-auto-columns: 1fr;
    grid-auto-flow: column;
    gap: 1px;
    background: var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.mode-btn {
    background: var(--bg-panel-solid);
    border: none;
    padding: 8px 12px;
    font-family: var(--font-body);
    font-size: 0.78rem;
    font-weight: 400;
    color: var(--text-secondary);
    cursor: pointer;
    transition: background 0.2s, color 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 0;
    line-height: 1;
}

.mode-btn:hover { color: var(--text); }

.mode-btn.active {
    background: var(--accent-subtle);
    color: var(--accent);
    font-weight: 500;
}

/* Checkbox label layout (standalone checkboxes, not .tog toggles) */
.checkbox-label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
}

.checkbox-label input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 36px;
    height: 20px;
    background: var(--slider-track);
    border-radius: 10px;
    position: relative;
    cursor: pointer;
    transition: background 180ms var(--ease-in-out);
    flex-shrink: 0;
}

.checkbox-label input[type="checkbox"]::after {
    content: '';
    position: absolute;
    top: 3px;
    left: 3px;
    width: 14px;
    height: 14px;
    background: var(--text-muted);
    border-radius: 50%;
    transition: all 180ms var(--ease-in-out);
}

.checkbox-label input[type="checkbox"]:checked {
    background: var(--accent-subtle);
}

.checkbox-label input[type="checkbox"]:checked::after {
    left: 19px;
    background: var(--accent);
}

/* ─── Ghost Buttons ─── */
.ghost-btn {
    padding: 0.4rem 0.75rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    font-family: var(--font-body);
    font-size: 0.78rem;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.ghost-btn:hover {
    background: var(--bg-hover);
    color: var(--text);
    border-color: var(--border-strong);
}

.ghost-btn:disabled,
.ghost-btn[disabled] {
    opacity: 0.4;
    cursor: default;
    pointer-events: none;
}

/* ─── Overlay / Dialog ─── */
.sim-overlay {
    position: fixed;
    inset: 0;
    z-index: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    animation: fadeIn 0.2s ease-out;
}

.sim-overlay[hidden],
.sim-overlay.hidden {
    display: none !important;
}

.sim-overlay-panel {
    max-width: 600px;
    width: 90vw;
    max-height: 80vh;
    display: flex;
    flex-direction: column;
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.sim-overlay-body {
    padding: 1rem 1.2rem;
    overflow-y: auto;
    font-size: 0.85rem;
    line-height: 1.6;
    -webkit-overflow-scrolling: touch;
}

.sim-overlay-body h3 {
    margin: 1em 0 0.3em;
    font-size: 0.9rem;
}

.sim-overlay-body p { margin: 0.4em 0; }
.sim-overlay-body ul, .sim-overlay-body ol { margin: 0.4em 0; padding-left: 1.2em; }

.sim-overlay-body .katex-display {
    overflow-x: auto;
    overflow-y: hidden;
    -webkit-overflow-scrolling: touch;
}

@media (max-width: 600px) {
    .sim-overlay-panel {
        width: 100vw;
        max-width: 100vw;
        max-height: 100vh;
        height: 100vh;
        border-radius: 0;
    }
    .sim-overlay { align-items: stretch; }
    .sim-overlay-body { font-size: 0.8rem; padding: 0.75rem 1rem; }
}

/* ─── Theme Toggle Icons ─── */
.icon-sun, .icon-moon { display: none; }
[data-theme="light"] .icon-sun { display: block; }
[data-theme="dark"] .icon-moon { display: block; }

/* ─── Control Group Label ─── */
label.control-label {
    font-size: 0.78rem;
    color: var(--text);
    font-weight: 400;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

/* ─── Toggle Switches ─── */
.tog-wrap { position: relative; }
.tog-wrap input { display: none; }

.tog {
    display: inline-flex;
    align-items: center;
    width: 42px;
    height: 22px;
    background: var(--tog-bg);
    border-radius: 11px;
    cursor: pointer;
    position: relative;
    border: 1px solid var(--tog-border);
    box-shadow: var(--tog-shadow);
    transition: all 0.28s ease;
    overflow: hidden;
    --tog-color: var(--accent);
    --tog-shift: 20px;
}

.tog-thumb {
    position: absolute;
    left: 3px;
    top: 3px;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--text-muted);
    box-shadow: 0 1px 3px var(--tog-thumb-shadow);
    transition: all 0.35s var(--ease-spring);
    z-index: 2;
}

.tog-icon {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    transition: opacity 0.28s ease;
    z-index: 1;
    line-height: 0;
    color: #fff;
}

.tog-icon-on { right: 5px; opacity: 0.25; }
.tog-icon-off { left: 5px; opacity: 0.6; }

.tog-wrap input:checked + .tog {
    background: linear-gradient(135deg, var(--tog-color), color-mix(in srgb, var(--tog-color), black 25%));
    border-color: color-mix(in srgb, var(--tog-color) 35%, transparent);
    box-shadow: inset 0 1px 3px var(--tog-checked-inset);
}
.tog-wrap input:checked + .tog .tog-thumb {
    transform: translateX(var(--tog-shift));
    background: var(--tog-thumb-on);
    box-shadow: 0 0 6px color-mix(in srgb, var(--tog-color) 50%, transparent);
}
.tog-wrap input:checked + .tog .tog-icon-on { opacity: 1; }
.tog-wrap input:checked + .tog .tog-icon-off { opacity: 0.25; }

.tog-wrap input:focus-visible + .tog {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Dark-mode toggle overrides */
[data-theme="dark"] .tog-wrap input:checked + .tog {
    background: linear-gradient(135deg, color-mix(in srgb, var(--tog-color), black 82%), color-mix(in srgb, var(--tog-color), black 72%));
    border-color: color-mix(in srgb, var(--tog-color) 22%, transparent);
}
[data-theme="dark"] .tog-wrap input:checked + .tog .tog-thumb {
    background: var(--tog-color);
    box-shadow: 0 0 8px color-mix(in srgb, var(--tog-color) 50%, transparent);
}

/* Larger touch targets on coarse pointers */
@media (pointer: coarse) {
    .tog { --tog-shift: 22px; width: 48px; height: 26px; border-radius: 13px; }
    .tog-thumb { width: 18px; height: 18px; }
}

/* ─── Reduced Motion ─── */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}