/* ================================================================
   INIT & RESPONSIVE — Splash screen, entrance animations,
   responsive typography, and panel resize foundation
   ================================================================ */

/* ── CSS Custom Properties for responsive scaling ── */
:root {
    --ui-scale: 1;
    --sidebar-width: 280px;
    --strip-h: 68px;
    --font-xs: calc(9px * var(--ui-scale));
    --font-sm: calc(11px * var(--ui-scale));
    --font-md: calc(13px * var(--ui-scale));
    --font-lg: calc(16px * var(--ui-scale));
    --font-xl: calc(20px * var(--ui-scale));
    --space-xs: calc(4px * var(--ui-scale));
    --space-sm: calc(6px * var(--ui-scale));
    --space-md: calc(10px * var(--ui-scale));
    --space-lg: calc(14px * var(--ui-scale));
}

/* ── SPLASH SCREEN ── */
#splash-screen {
    position: fixed;
    inset: 0;
    z-index: 99999;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: #0a0d12;
    /* GPU-composited: isolate from main thread layout work */
    will-change: opacity;
    transform: translateZ(0);
    contain: strict;
    opacity: 1;
    transition: opacity 0.6s cubic-bezier(0.4, 0, 0.6, 1); /* Smooth ease-in-out */
    pointer-events: auto;
}

#splash-screen.fade-out {
    opacity: 0;
    pointer-events: none;
}

/* Ready state - triggers final flourish before fadeout */
#splash-screen.ready .splash-title {
    text-shadow: 0 0 80px rgba(100, 180, 255, 0.5),
                 0 0 160px rgba(100, 180, 255, 0.2);
}
#splash-screen.ready .splash-subtitle {
    color: rgba(255, 255, 255, 0.55);
    letter-spacing: 0.48em;
}
#splash-screen.ready .splash-progress {
    opacity: 0;
    transform: scaleX(1.1) translateZ(0);
}

.splash-title {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', sans-serif;
    font-size: clamp(36px, 5vw, 64px);
    font-weight: 200;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.95);
    text-shadow: 0 0 60px rgba(100, 180, 255, 0.25),
                 0 0 120px rgba(100, 180, 255, 0.08);
    will-change: transform, opacity, text-shadow;
    transform: translateY(10px) translateZ(0);
    backface-visibility: hidden;
    opacity: 0;
    animation: splashTitleIn 0.7s cubic-bezier(0.25, 0.1, 0.25, 1) 0.1s forwards; /* ease-in-out */
    transition: text-shadow 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
    user-select: none;
}

.splash-subtitle {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', sans-serif;
    font-size: clamp(11px, 1.5vw, 14px);
    font-weight: 500;
    letter-spacing: 0.4em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.4);
    margin-top: 20px;
    will-change: opacity, transform, letter-spacing, color;
    transform: translateY(8px) translateZ(0);
    backface-visibility: hidden;
    opacity: 0;
    animation: splashSubIn 0.6s cubic-bezier(0.25, 0.1, 0.25, 1) 0.4s forwards; /* ease-in-out */
    transition: color 0.4s cubic-bezier(0.25, 0.1, 0.25, 1), letter-spacing 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
    user-select: none;
}

/* Progress bar - shows actual loading state */
.splash-progress {
    width: 120px;
    height: 2px;
    margin-top: 32px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 1px;
    overflow: hidden;
    will-change: opacity, transform;
    opacity: 0;
    transform: translateZ(0);
    animation: splashProgressIn 0.5s cubic-bezier(0.25, 0.1, 0.25, 1) 0.6s forwards;
    transition: opacity 0.4s cubic-bezier(0.25, 0.1, 0.25, 1), transform 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.splash-progress-bar {
    width: 0%;
    height: 100%;
    background: linear-gradient(90deg, rgba(100, 180, 255, 0.6), rgba(140, 200, 255, 0.8));
    border-radius: 1px;
    transition: width 0.2s cubic-bezier(0.25, 0.1, 0.25, 1); /* Smooth ease-in-out */
}

@keyframes splashTitleIn {
    0% { opacity: 0; transform: translateY(10px) translateZ(0); }
    100% { opacity: 1; transform: translateY(0) translateZ(0); }
}
@keyframes splashSubIn {
    0% { opacity: 0; transform: translateY(8px) translateZ(0); }
    100% { opacity: 1; transform: translateY(0) translateZ(0); }
}
@keyframes splashProgressIn {
    0% { opacity: 0; }
    100% { opacity: 1; }
}

/* ── UI ENTRANCE ANIMATIONS ── */

/* Initial hidden states — applied by JS before first paint */
#mixer-strip.ui-enter {
    will-change: transform, opacity;
    transform: translateY(-100%);
    opacity: 0;
}

#sidebar-right.ui-enter {
    will-change: transform, opacity;
    transform: translateX(100%);
    opacity: 0;
}

#canvas-area.ui-enter {
    will-change: opacity;
    opacity: 0;
}

#custom-titlebar.ui-enter {
    will-change: transform, opacity;
    transform: translateY(-100%);
    opacity: 0;
}

/* Animate-in classes — triggered by JS in sequence */
#custom-titlebar.ui-enter.ui-ready {
    transform: translateY(0);
    opacity: 1;
    transition: transform 0.5s cubic-bezier(0.25, 0.1, 0.25, 1),
                opacity 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}

#mixer-strip.ui-enter.ui-ready {
    transform: translateY(0);
    opacity: 1;
    transition: transform 0.55s cubic-bezier(0.25, 0.1, 0.25, 1),
                opacity 0.45s cubic-bezier(0.25, 0.1, 0.25, 1);
}

#sidebar-right.ui-enter.ui-ready {
    transform: translateX(0);
    opacity: 1;
    transition: transform 0.55s cubic-bezier(0.25, 0.1, 0.25, 1),
                opacity 0.45s cubic-bezier(0.25, 0.1, 0.25, 1);
}

#canvas-area.ui-enter.ui-ready {
    opacity: 1;
    transition: opacity 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
}

/* Clean up will-change after animation completes */
#mixer-strip.ui-settled,
#sidebar-right.ui-settled,
#canvas-area.ui-settled,
#custom-titlebar.ui-settled {
    will-change: auto;
}

/* ── RESPONSIVE UI SCALING ── */
/* CSS zoom scales ALL content (fonts, padding, borders, icons) proportionally.
   --ui-scale is set by JS in initResponsiveScale() based on screen DPI/resolution. */

#sidebar-right {
    zoom: var(--ui-scale);
}
#mixer-strip {
    zoom: var(--ui-scale);
}
#colorBar {
    zoom: var(--ui-scale);
}
/* Floating panels / overlays */
.stats-panel {
    zoom: var(--ui-scale);
}
.rec-drawer {
    zoom: var(--ui-scale);
}
#hotkeyOverlay {
    zoom: var(--ui-scale);
}
.delete-modal {
    zoom: var(--ui-scale);
}
.hotkey-reminder {
    zoom: var(--ui-scale);
}
#settingsToggleBtn {
    zoom: var(--ui-scale);
}
#settingsPanel {
    zoom: var(--ui-scale);
}
.mask-editor-overlay {
    zoom: var(--ui-scale);
}
.fps-notification {
    zoom: var(--ui-scale);
}
.arm-colors-panel {
    zoom: var(--ui-scale);
}

/* Canvas wrapper accounts for zoomed sidebar width */
#canvas-wrapper {
    max-width: calc(100vw - var(--sidebar-width) * var(--ui-scale) - 10px) !important;
}

/* ── PANEL RESIZE FOUNDATION ── */
#sidebar-right {
    position: relative;
    min-width: 220px;
    max-width: 420px;
}

/* Resize grip on left edge of sidebar */
.sidebar-resize-handle {
    position: absolute;
    top: 0;
    left: -3px;
    width: 6px;
    height: 100%;
    cursor: ew-resize;
    z-index: 200;
    background: transparent;
}
.sidebar-resize-handle:hover,
.sidebar-resize-handle.active {
    opacity: 0.7;
}

/* ── LAYER PANEL OVERHAUL ── */

/* Override the cramped layer layout */
#sidebar-right .layer-item {
    padding: 8px 10px;
    margin-bottom: 6px;
    gap: 6px;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.04);
}
#sidebar-right .layer-item.active-layer {
    background: rgba(100, 200, 255, 0.1);
    border: 1px solid rgba(100, 200, 255, 0.35);
}

/* Header: wrap into two rows — thumbnail+title on top, buttons below */
#sidebar-right .layer-item-header {
    display: grid;
    grid-template-columns: 36px 1fr;
    grid-template-rows: auto auto;
    gap: 6px 8px;
    align-items: center;
}

/* Thumbnail */
#sidebar-right .layer-thumbnail {
    width: 36px;
    height: 36px;
    border-radius: 6px;
    grid-row: 1;
    grid-column: 1;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

/* Title info area - gets full remaining width */
#sidebar-right .layer-info {
    grid-row: 1;
    grid-column: 2;
    min-width: 0;
    display: flex;
    align-items: center;
}

/* Title input - clean, not competing for space */
#sidebar-right .layer-title {
    width: 100%;
    font-size: var(--font-sm);
    padding: 3px 6px;
    border-radius: 4px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: rgba(255, 255, 255, 0.9);
    font-weight: 500;
    text-overflow: ellipsis;
    overflow: hidden;
    white-space: nowrap;
}
#sidebar-right .layer-title:focus {
    border-color: rgba(100, 200, 255, 0.4);
    background: rgba(0, 0, 0, 0.35);
    outline: none;
}

/* Controls row - spans full width below thumbnail+title */
#sidebar-right .layer-controls {
    grid-row: 2;
    grid-column: 1 / -1;
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
}

/* Compact layer buttons with clearer styling */
#sidebar-right .layer-btn {
    padding: 3px 7px;
    font-size: calc(10px * var(--ui-scale));
    min-width: auto;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.04);
    line-height: 1.2;
}

/* Mask control buttons */
#sidebar-right .layer-mask-controls {
    padding: 0;
}
#sidebar-right .mask-control-btn {
    font-size: calc(10px * var(--ui-scale));
    padding: 4px 8px;
    border-radius: 4px;
}

/* Threshold / Feather slider row */
#sidebar-right .layer-threshold {
    font-size: calc(10px * var(--ui-scale));
    gap: 6px;
    opacity: 0.85;
    margin-bottom: 14px; /* Extra breathing room below */
}
#sidebar-right .layer-threshold .layer-slider-host {
    flex: 1;
    display: flex;
    align-items: center;
}
#sidebar-right .layer-threshold span:first-child,
#sidebar-right .layer-threshold .layer-slider-value {
    margin-top: 10px; /* Nudge label and value down to align with slider knob center */
}
/* Remove ALL dark borders from sidebar sliders */
#sidebar-right input[type="range"] {
    box-shadow: none !important;
    border: none !important;
}
#sidebar-right input[type="range"]::-webkit-slider-container {
    box-shadow: none !important;
    border: none !important;
}
#sidebar-right input[type="range"]::-webkit-slider-runnable-track {
    box-shadow: none !important;
    border: none !important;
}
#sidebar-right input[type="range"]::-moz-range-track {
    box-shadow: none !important;
    border: none !important;
}
#sidebar-right input[type="range"]::-moz-range-progress {
    box-shadow: none !important;
    border: none !important;
}
#sidebar-right .layer-threshold span:first-child {
    font-size: calc(9px * var(--ui-scale));
    text-transform: uppercase;
    letter-spacing: 0.3px;
    opacity: 0.6;
    min-width: 42px;
    flex-shrink: 0;
}
#sidebar-right .layer-slider-value {
    font-family: 'Courier New', monospace;
    font-size: calc(10px * var(--ui-scale));
    min-width: 32px;
    text-align: right;
    color: #4fc3f7;
    font-weight: 600;
}

/* Collision controls - cleaner layout */
#sidebar-right .collision-controls {
    padding: 6px 8px;
    background: rgba(255, 160, 60, 0.04);
    border: 1px solid rgba(255, 160, 60, 0.1);
    border-radius: 6px;
}
#sidebar-right .collision-row {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 8px;
    padding: 6px 0; /* Space for slider thumb overflow */
}
#sidebar-right .collision-row:last-child {
    margin-bottom: 0;
}
#sidebar-right .collision-label {
    font-size: calc(9px * var(--ui-scale));
    text-transform: uppercase;
    letter-spacing: 0.3px;
    opacity: 0.55;
    min-width: 52px;
    flex-shrink: 0;
}
#sidebar-right .collision-mode-select {
    flex: 1;
    height: 24px;
    font-size: calc(10px * var(--ui-scale));
    padding: 2px 4px;
}
#sidebar-right .collision-strength-val,
#sidebar-right .collision-threshold-val {
    font-family: 'Courier New', monospace;
    font-size: calc(10px * var(--ui-scale));
    min-width: 28px;
    text-align: right;
    color: rgba(255, 170, 80, 0.85);
    font-weight: 600;
}

/* Drop zone polish */
#sidebar-right .drop-zone {
    height: 32px;
    border-radius: 6px;
    font-size: calc(9px * var(--ui-scale));
    margin-bottom: 6px;
    border-width: 1px;
    border-style: dashed;
}

/* Layers panel scrollable area */
#sidebar-right .layers-panel {
    max-height: 340px;
    margin-top: 4px;
    padding-right: 2px;
}

/* Layers panel scrollbar */
#sidebar-right .layers-panel::-webkit-scrollbar { width: 4px; }
#sidebar-right .layers-panel::-webkit-scrollbar-track { background: transparent; }
#sidebar-right .layers-panel::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.12); border-radius: 2px; }