/* ============================================================
   Reel Generator — full-screen tool UI
   No borders. Separation via background, shadow, spacing.
   ============================================================ */

:root {
    --bg-app: #1C1C1C;
    --bg-stage: #000000;
    --bg-panel: #1C1C1C;
    --bg-panel-2: #404040;
    --bg-input: #000000;
    --bg-input-hover: #404040;
    --bg-accent: #F5F5F5;
    --bg-accent-hover: #FFFFFF;

    --fg: #F5F5F5;
    --fg-dim: #C8C8C8;
    --fg-mute: #6B6B6B;
    --fg-on-accent: #000000;

    --accent: #F5F5F5;
    --accent-glow: rgba(245, 245, 245, 0.18);
    --highlight: #FF4040;
    --success: #2DC05E;

    --color-spark-blue:   #2979FF;
    --color-arc-violet:   #8840EE;
    --color-blaze-orange: #FF6B1A;
    --color-pop-yellow:   #FFCB00;
    --color-lime-surge:   #90D020;

    --r-sm: 8px;
    --r-md: 12px;
    --r-lg: 18px;
    --r-pill: 999px;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.55);

    --gap: 14px;
    --gap-lg: 22px;

    --header-h: 64px;
    --side-w: 360px;
    --files-min-h: 132px;

    --font-sans: "Google Sans", -apple-system, BlinkMacSystemFont, Arial, Helvetica, sans-serif;

    --pattern-ink: rgba(255, 255, 255, 0.045);
    --pattern-ink-strong: rgba(255, 255, 255, 0.09);

    --ambient-warm: rgba(255, 255, 255, 0.04);
    --ambient-orange: rgba(255, 255, 255, 0.05);
    --stage-glow: rgba(255, 255, 255, 0.04);

    --canvas-shadow: 0 30px 80px rgba(0, 0, 0, 0.55), 0 6px 18px rgba(0, 0, 0, 0.4);
    --btn-primary-shadow: 0 4px 6px rgba(255, 255, 255, 0.16);
    --btn-primary-shadow-hover: 0 6px 12px rgba(255, 255, 255, 0.28);
    --slider-thumb-shadow: 0 2px 8px rgba(255, 255, 255, 0.3);
    --frame-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);

    --frames-bar-bg: rgba(0, 0, 0, 0.35);
    --frame-overlay: rgba(0, 0, 0, 0.55);
    --frame-remove-bg: rgba(0, 0, 0, 0.65);
    --frame-handle-stripe: rgba(255, 255, 255, 0.5);
    --frame-handle-fade: linear-gradient(90deg, transparent 0%, rgba(255, 255, 255, 0) 30%, rgba(255, 255, 255, 0.18) 100%);
    --thumb-remove-hover: rgba(255, 255, 255, 0.06);
    --drop-target-tint: rgba(255, 255, 255, 0.06);
    --drop-target-tint-soft: rgba(255, 255, 255, 0.04);

    --scrim: rgba(0, 0, 0, 0.78);
    --scrim-light: rgba(0, 0, 0, 0.55);
    --scrim-card: rgba(28, 28, 28, 0.85);
    --scrim-card-loader: rgba(28, 28, 28, 0.92);
    --focus-ring-outer: rgba(0, 0, 0, 0.3);

    --scroll-thumb: var(--bg-panel-2);

    --ease: cubic-bezier(0.32, 0.72, 0.24, 1);
    --dur: 220ms;
}

.app[data-theme="light"] {
    --pattern-ink: rgba(0, 0, 0, 0.07);
    --pattern-ink-strong: rgba(0, 0, 0, 0.14);

    --bg-app: #E8E8E8;
    --bg-stage: #C8C8C8;
    --bg-panel: #FFFFFF;
    --bg-panel-2: #F5F5F5;
    --bg-input: #E8E8E8;
    --bg-input-hover: #C8C8C8;
    --bg-accent: #1C1C1C;
    --bg-accent-hover: #000000;

    --fg: #1C1C1C;
    --fg-dim: #404040;
    --fg-mute: #9A9A9A;
    --fg-on-accent: #FFFFFF;

    --accent: #1C1C1C;
    --accent-glow: rgba(28, 28, 28, 0.18);
    --highlight: #FF4040;
    --success: #2DC05E;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.10);
    --shadow-md: 0 6px 22px rgba(0, 0, 0, 0.10);
    --shadow-lg: 0 16px 50px rgba(0, 0, 0, 0.18);

    --ambient-warm: rgba(255, 255, 255, 0.55);
    --ambient-orange: rgba(0, 0, 0, 0.04);
    --stage-glow: rgba(255, 255, 255, 0.45);

    --canvas-shadow: 0 24px 56px rgba(0, 0, 0, 0.18), 0 4px 14px rgba(0, 0, 0, 0.10);
    --btn-primary-shadow: 0 4px 6px rgba(0, 0, 0, 0.12);
    --btn-primary-shadow-hover: 0 6px 12px rgba(0, 0, 0, 0.18);
    --slider-thumb-shadow: 0 2px 8px rgba(0, 0, 0, 0.18);
    --frame-shadow: 0 4px 12px rgba(0, 0, 0, 0.10);

    --frames-bar-bg: rgba(0, 0, 0, 0.05);
    --frame-overlay: rgba(255, 255, 255, 0.85);
    --frame-remove-bg: rgba(255, 255, 255, 0.92);
    --frame-handle-stripe: rgba(0, 0, 0, 0.4);
    --frame-handle-fade: linear-gradient(90deg, transparent 0%, rgba(0, 0, 0, 0) 30%, rgba(0, 0, 0, 0.16) 100%);
    --thumb-remove-hover: rgba(0, 0, 0, 0.06);
    --drop-target-tint: rgba(0, 0, 0, 0.06);
    --drop-target-tint-soft: rgba(0, 0, 0, 0.04);

    --scrim: rgba(232, 232, 232, 0.78);
    --scrim-light: rgba(0, 0, 0, 0.18);
    --scrim-card: rgba(255, 255, 255, 0.95);
    --scrim-card-loader: rgba(255, 255, 255, 0.97);
    --focus-ring-outer: rgba(0, 0, 0, 0.12);

    --scroll-thumb: var(--bg-input-hover);
}

::view-transition-old(root),
::view-transition-new(root) {
    animation-duration: 1.5s;
    animation-timing-function: var(--ease);
}

* {
    box-sizing: border-box;
}

html,
body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
    background: var(--bg-app);
    color: var(--fg);
    font-family: var(--font-sans);
    font-size: 14px;
    line-height: 1.45;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

button {
    font-family: inherit;
    font-size: inherit;
    background: none;
    border: 0;
    padding: 0;
    color: inherit;
    cursor: pointer;
}

input,
select,
textarea,
output {
    font-family: inherit;
    font-size: inherit;
    color: inherit;
}

/* ----- App shell ------------------------------------------- */

.app {
    display: grid;
    grid-template-rows: var(--header-h) 1fr;
    width: 100vw;
    height: 100vh;
    background:
        radial-gradient(60% 40% at 90% 100%, var(--ambient-orange) 0%, transparent 60%),
        var(--bg-app);
}

/* ----- Header --------------------------------------------- */

.app-header {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    padding: 0 22px;
    gap: 22px;
}

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

.brand-logo {
    height: 32px;
    width: auto;
    display: block;
}

.header-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

.btn-ghost,
.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 9px 18px;
    border-radius: var(--r-pill);
    font-weight: 600;
    font-size: 13px;
    transition:
        background var(--dur) var(--ease),
        color var(--dur) var(--ease),
        transform var(--dur) var(--ease),
        box-shadow var(--dur) var(--ease);
}

.btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: var(--r-pill);
    background: var(--bg-panel);
    color: var(--fg-dim);
    transition:
        background var(--dur) var(--ease),
        color var(--dur) var(--ease),
        transform var(--dur) var(--ease);
}

.btn-icon:hover {
    background: var(--bg-panel-2);
    color: var(--fg);
}

#clear-timeline-btn:hover:not(:disabled) {
    color: var(--highlight);
}

.btn-icon:active {
    transform: scale(0.94);
}

.btn-icon .icon-moon { display: none; }
.btn-icon .icon-sun  { display: block; }

.app[data-theme="light"] .btn-icon .icon-moon { display: block; }
.app[data-theme="light"] .btn-icon .icon-sun  { display: none; }

.btn-ghost {
    background: var(--bg-panel);
    color: var(--fg-dim);
}

.btn-ghost:hover {
    background: var(--bg-panel-2);
    color: var(--fg);
}

.btn-ghost:active {
    transform: translateY(1px);
}

.btn-primary {
    background: var(--bg-accent);
    color: var(--fg-on-accent);
    box-shadow: var(--btn-primary-shadow);
}

.btn-primary:hover:not(:disabled) {
    background: var(--bg-accent-hover);
    box-shadow: var(--btn-primary-shadow-hover);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(1px);
}

.btn-primary:disabled {
    background: var(--bg-panel-2);
    color: var(--fg-mute);
    cursor: not-allowed;
    box-shadow: none;
}

.btn-spinner {
    display: none;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: conic-gradient(transparent 0deg, currentColor 280deg, transparent 360deg);
    -webkit-mask: radial-gradient(circle, transparent 5px, #000 6px);
    mask: radial-gradient(circle, transparent 5px, #000 6px);
    animation: spin 0.8s linear infinite;
}

.btn-primary.is-busy .btn-spinner {
    display: inline-block;
}

.btn-primary.is-busy .btn-label {
    opacity: 0.6;
}

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

/* ----- Body layout ---------------------------------------- */

.app-body {
    display: grid;
    grid-template-columns: 1fr var(--side-w);
    gap: var(--gap);
    padding: 0 var(--gap) var(--gap) var(--gap);
    min-height: 0;
}

.panel {
    background: var(--bg-panel);
    border-radius: var(--r-lg);
    box-shadow: var(--shadow-md);
    min-height: 0;
    overflow: hidden;
}

/* ----- Stage ---------------------------------------------- */

.panel-stage {
    display: grid;
    grid-template-rows: 1fr auto auto;
    background-color: var(--bg-stage);
    padding: 22px;
    gap: 14px;
    background-image:
        radial-gradient(60% 50% at 50% 0%, var(--stage-glow) 0%, transparent 60%);
    transition: background-color 1.5s var(--ease);
}

.stage-frame {
    position: relative;
    display: grid;
    place-items: center;
    background-color: var(--bg-stage);
    background-image: repeating-linear-gradient(45deg, var(--pattern-ink) 0 12px, transparent 12px 24px);
    border-radius: var(--r-md);
    overflow: hidden;
    min-height: 0;
    transition: background-color 1.5s var(--ease);
}

.stage-canvas {
    display: block;
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
    border-radius: 32px;
    box-shadow: var(--canvas-shadow);
    background: #000;
}

.stage-empty {
    position: absolute;
    inset: 0;
    display: grid;
    place-items: center;
    grid-auto-flow: row;
    gap: 14px;
    color: var(--fg-mute);
    text-align: center;
    pointer-events: none;
    transition: opacity var(--dur) var(--ease);
}

.stage-empty-icon {
    color: var(--fg-mute);
}

.stage-empty-text {
    font-size: 14px;
    letter-spacing: 0.02em;
}

.app[data-has-images="true"] .stage-empty {
    opacity: 0;
}

.stage-controls {
    display: flex;
    align-items: center;
    gap: 14px;
}

.play-btn {
    display: inline-flex;
    align-items: center;
    gap: 9px;
    padding: 8px 16px 8px 12px;
    background: var(--bg-panel);
    color: var(--fg);
    border-radius: var(--r-pill);
    font-weight: 600;
    font-size: 13px;
    transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.play-btn:hover:not(:disabled) {
    background: var(--bg-panel-2);
}

.play-btn:active:not(:disabled) {
    transform: scale(0.97);
}

.play-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.play-icon {
    display: inline-grid;
    place-items: center;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: var(--bg-accent);
    color: var(--fg-on-accent);
}

.play-btn .icon-pause,
.play-btn.is-playing .icon-play {
    display: none;
}

.play-btn.is-playing .icon-pause {
    display: block;
}

.play-label {
    display: inline-block;
    min-width: 4.5em;
    text-align: center;
}

.timeline {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 12px;
}

.timeline-track {
    position: relative;
    flex: 1;
    height: 4px;
    background: var(--bg-panel);
    border-radius: var(--r-pill);
    overflow: hidden;
}

.timeline-fill {
    position: absolute;
    inset: 0 auto 0 0;
    width: 0%;
    background: linear-gradient(in hsl to right, var(--highlight) 16.67%, var(--color-pop-yellow) 50%, var(--success) 83.33%) left center / 100% 100% no-repeat;
    border-radius: var(--r-pill);
    transition: width 80ms linear;
}

.timeline-time {
    font-variant-numeric: tabular-nums;
    color: var(--fg-dim);
    font-size: 12px;
    min-width: 44px;
    text-align: right;
}

/* ----- Side column (Files + Tweaks, full height) --------- */

.panel-side {
    --side-files-h: var(--files-min-h);
    display: grid;
    grid-template-rows: var(--side-files-h) 8px 1fr;
    background: var(--bg-panel);
}

.app[data-has-images="false"] .panel-side {
    grid-template-rows: var(--files-min-h);
}

.app[data-has-images="false"] .side-files .thumbnails,
.app[data-has-images="false"] .side-resizer,
.app[data-has-images="false"] .side-tweaks {
    display: none;
}

.side-files {
    position: relative;
    padding: 18px 16px;
    gap: 12px;
}

.side-block {
    display: flex;
    flex-direction: column;
    min-height: 0;
    overflow: hidden;
}

.side-tweaks {
    background: var(--bg-panel-2);
    padding: 16px 6px 18px 16px;
}

.library-status {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-right: 6px;
    padding: 0 4px;
    font-size: 12px;
    font-weight: 500;
    color: var(--fg-dim);
    transition: opacity var(--dur) var(--ease);
    white-space: nowrap;
}

.library-status[data-state="idle"] {
    opacity: 0;
    pointer-events: none;
}

.library-status-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--fg-mute);
    transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.library-status[data-state="ready"] .library-status-dot {
    background: var(--success);
    box-shadow: 0 0 8px rgba(93, 216, 122, 0.45);
}

.library-status[data-state="working"] .library-status-dot {
    background: var(--highlight);
    box-shadow: 0 0 8px rgba(255, 122, 61, 0.6);
    animation: pulse 1.4s ease-in-out infinite;
}

.library-status[data-state="error"] .library-status-dot {
    background: #e85b5b;
    box-shadow: 0 0 8px rgba(232, 91, 91, 0.5);
}

/* ----- Dropzone ------------------------------------------ */

.dropzone {
    position: relative;
    display: grid;
    place-items: center;
    padding: 18px;
    background: var(--bg-input);
    border-radius: var(--r-md);
    cursor: pointer;
    transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.dropzone:hover {
    background-color: var(--bg-input-hover);
}

.dropzone.is-dragover {
    background-color: var(--drop-target-tint);
    transform: scale(1.01);
}

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

.dropzone-inner {
    display: grid;
    justify-items: center;
    gap: 6px;
    text-align: center;
    pointer-events: none;
}

.dropzone-icon {
    color: var(--fg-dim);
}

.dropzone-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--fg);
}

.dropzone-hint {
    font-size: 11px;
    color: var(--fg-mute);
    letter-spacing: 0.04em;
}

/* ----- Thumbnails ---------------------------------------- */

.thumbnails {
    list-style: none;
    margin: 0;
    padding: 0 6px 0 0;
    overflow-y: auto;
    display: grid;
    gap: 6px;
    flex: 1;
    min-height: 0;
    scrollbar-width: thin;
    scrollbar-color: var(--scroll-thumb) transparent;
}

.thumbnails::-webkit-scrollbar {
    width: 6px;
}

.thumbnails::-webkit-scrollbar-thumb {
    background: var(--scroll-thumb);
    border-radius: var(--r-pill);
}

.thumbnail {
    display: grid;
    grid-template-columns: 18px 44px 1fr auto;
    align-items: center;
    gap: 10px;
    padding: 6px;
    background: var(--bg-input);
    border-radius: var(--r-sm);
    cursor: grab;
    transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.thumbnail:hover {
    background: var(--bg-input-hover);
}

.thumbnail.is-dragging {
    opacity: 0.4;
    cursor: grabbing;
}

.thumbnail.is-drop-target {
    box-shadow: 0 0 0 2px var(--accent-glow);
}

.thumb-handle {
    display: grid;
    place-items: center;
    color: var(--fg-mute);
    font-size: 14px;
    line-height: 1;
}

.thumb-img {
    width: 44px;
    height: 44px;
    object-fit: cover;
    border-radius: 4px;
    background: #000;
    display: block;
}

.thumb-meta {
    display: grid;
    gap: 1px;
    min-width: 0;
}

.thumb-name {
    font-size: 12px;
    color: var(--fg);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.thumb-size {
    font-size: 10px;
    color: var(--fg-mute);
    letter-spacing: 0.02em;
}

.thumb-remove {
    width: 24px;
    height: 24px;
    display: grid;
    place-items: center;
    border-radius: 50%;
    color: var(--fg-mute);
    background: transparent;
    transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.thumb-remove:hover {
    background: var(--thumb-remove-hover);
    color: var(--fg);
}

/* ----- Tweaks ------------------------------------------- */

.side-tweaks {
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--bg-panel) transparent;
}

.side-tweaks::-webkit-scrollbar {
    width: 6px;
}

.side-tweaks::-webkit-scrollbar-thumb {
    background: var(--bg-panel);
    border-radius: var(--r-pill);
}

.control-group {
    display: grid;
    gap: 12px;
    padding: 14px 16px 14px 0;
    margin-right: 10px;
    background: transparent;
}

.control-group + .control-group {
    margin-top: 6px;
    padding-top: 18px;
}

.group-title {
    font-size: 10px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.16em;
    color: var(--fg-mute);
}

.control {
    display: grid;
    gap: 7px;
}

.control-label {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    font-size: 12px;
    font-weight: 500;
    color: var(--fg);
}

.control-label output {
    font-size: 11px;
    font-variant-numeric: tabular-nums;
    color: var(--fg-dim);
    font-weight: 600;
}

.control-hint {
    font-size: 10px;
    color: var(--fg-mute);
    letter-spacing: 0.02em;
}

/* range slider */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    background: transparent;
    width: 100%;
    height: 22px;
    margin: 0;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-runnable-track {
    height: 4px;
    background: var(--bg-input);
    border-radius: var(--r-pill);
}

input[type="range"]::-moz-range-track {
    height: 4px;
    background: var(--bg-input);
    border-radius: var(--r-pill);
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--accent);
    margin-top: -5px;
    box-shadow: var(--slider-thumb-shadow);
    transition: transform var(--dur) var(--ease);
}

input[type="range"]::-moz-range-thumb {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: var(--slider-thumb-shadow);
    transition: transform var(--dur) var(--ease);
    border: 0;
}

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

input[type="range"]:hover::-moz-range-thumb {
    transform: scale(1.15);
}

/* select */
.select-wrap {
    position: relative;
    display: block;
}

.select-wrap::after {
    content: "";
    position: absolute;
    right: 12px;
    top: 50%;
    width: 7px;
    height: 7px;
    transform: translateY(-65%) rotate(45deg);
    box-shadow: inset -2px -2px 0 var(--fg-dim);
    pointer-events: none;
}

.select-wrap select {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    width: 100%;
    padding: 9px 32px 9px 12px;
    background: var(--bg-input);
    border: 0;
    border-radius: var(--r-sm);
    color: var(--fg);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: background var(--dur) var(--ease);
}

.select-wrap select:hover,
.select-wrap select:focus-visible {
    background: var(--bg-input-hover);
    outline: none;
    box-shadow: 0 0 0 2px var(--accent-glow);
}

/* segmented control */
.segmented {
    display: grid;
    grid-template-columns: 1fr 1fr;
    background: var(--bg-input);
    border-radius: var(--r-sm);
    padding: 3px;
    gap: 2px;
}

.segmented input {
    display: none;
}

.segmented label {
    display: grid;
    place-items: center;
    padding: 6px 0;
    font-size: 12px;
    font-weight: 500;
    color: var(--fg-dim);
    border-radius: 6px;
    cursor: pointer;
    transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.segmented label:hover {
    color: var(--fg);
}

.segmented input:checked + label {
    background: var(--bg-panel);
    color: var(--fg);
    box-shadow: var(--shadow-sm);
}

/* color picker */
.color-row {
    display: grid;
    grid-template-columns: 32px 1fr;
    gap: 10px;
    align-items: center;
    background: var(--bg-input);
    border-radius: var(--r-sm);
    padding: 5px 12px 5px 5px;
}

input[type="color"] {
    width: 100%;
    height: 26px;
    background: transparent;
    border: 0;
    padding: 0;
    cursor: pointer;
    border-radius: 4px;
    overflow: hidden;
}

input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 0;
}

input[type="color"]::-webkit-color-swatch {
    border: 0;
    border-radius: 4px;
}

input[type="color"]::-moz-color-swatch {
    border: 0;
    border-radius: 4px;
}

.color-hex {
    font-size: 11px;
    color: var(--fg-dim);
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.04em;
}

[data-when-fit] {
    display: none;
}

.app[data-fit="contain"] [data-when-fit="contain"] {
    display: grid;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50%      { opacity: 0.4; }
}

/* ----- Responsive --------------------------------------- */

@media (max-width: 980px) {
    :root {
        --side-w: 320px;
        --header-h: 56px;
    }

    .brand-name {
        font-size: 18px;
    }
}

@media (max-width: 760px) {
    .app {
        grid-template-rows: auto 1fr;
    }

    .app-body {
        grid-template-columns: 1fr;
        grid-template-rows: minmax(50vh, 1fr) minmax(40vh, 1fr);
    }

    .panel-side {
        grid-template-rows: auto 0 auto;
    }
}

/* focus ring (no border) */
button:focus-visible,
select:focus-visible,
input:focus-visible {
    outline: none;
    box-shadow: 0 0 0 2px var(--accent-glow), 0 0 0 4px var(--focus-ring-outer);
}

/* ----- Side resizer ------------------------------------- */

.side-resizer {
    position: relative;
    cursor: ns-resize;
    background: var(--bg-panel);
    display: grid;
    place-items: center;
    transition: background var(--dur) var(--ease);
}

.side-resizer:hover,
.side-resizer.is-active {
    background: var(--bg-panel-2);
}

.side-resizer-grip {
    width: 38px;
    height: 3px;
    background: var(--fg-mute);
    border-radius: var(--r-pill);
    opacity: 0.5;
    transition: opacity var(--dur) var(--ease);
}

.side-resizer:hover .side-resizer-grip,
.side-resizer.is-active .side-resizer-grip {
    opacity: 1;
}

/* ----- Frames bar --------------------------------------- */

.frames-bar {
    list-style: none;
    margin: 0;
    padding: 8px;
    display: flex;
    gap: 4px;
    overflow-x: auto;
    overflow-y: hidden;
    background: var(--frames-bar-bg);
    border-radius: var(--r-md);
    min-height: 84px;
    align-items: stretch;
    scrollbar-width: thin;
    scrollbar-color: var(--scroll-thumb) transparent;
    transition: background var(--dur) var(--ease);
}

.frames-bar::-webkit-scrollbar {
    height: 6px;
}

.frames-bar::-webkit-scrollbar-thumb {
    background: var(--scroll-thumb);
    border-radius: var(--r-pill);
}

.frames-bar.is-drop-target {
    background: var(--drop-target-tint);
}

.frames-bar-empty {
    display: grid;
    place-items: center;
    width: 100%;
    color: var(--fg-mute);
    font-size: 12px;
    letter-spacing: 0.02em;
    pointer-events: none;
}

.frames-bar[data-empty="false"] .frames-bar-empty {
    display: none;
}

.frame-item {
    position: relative;
    display: grid;
    grid-template-rows: 1fr auto;
    flex-shrink: 0;
    height: 68px;
    background: var(--bg-panel);
    border-radius: var(--r-sm);
    overflow: hidden;
    cursor: grab;
    transition:
        transform var(--dur) var(--ease),
        box-shadow var(--dur) var(--ease);
}

.frame-item:hover {
    box-shadow: var(--frame-shadow);
}

.frame-item.is-dragging {
    opacity: 0.4;
    cursor: grabbing;
}

.frame-item.is-drop-before {
    box-shadow: -2px 0 0 0 var(--accent), var(--frame-shadow);
}

.frame-item.is-drop-after {
    box-shadow: 2px 0 0 0 var(--accent), var(--frame-shadow);
}

.frame-thumb {
    width: 100%;
    height: 100%;
    background-color: #000;
    background-position: center;
    background-size: cover;
    pointer-events: none;
}

.frame-duration {
    text-align: center;
    font-size: 10px;
    font-weight: 600;
    padding: 3px 4px;
    background: var(--frame-overlay);
    color: var(--fg);
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.02em;
    pointer-events: none;
}

.frame-handle {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    width: 8px;
    cursor: ew-resize;
    background: var(--frame-handle-fade);
    opacity: 0;
    transition: opacity var(--dur) var(--ease);
}

.frame-item:hover .frame-handle,
.frame-item.is-resizing .frame-handle {
    opacity: 1;
}

.frame-handle::after {
    content: "";
    position: absolute;
    right: 2px;
    top: 50%;
    transform: translateY(-50%);
    width: 2px;
    height: 16px;
    border-radius: 2px;
    background: var(--frame-handle-stripe);
}

.frame-remove {
    position: absolute;
    top: 4px;
    left: 4px;
    width: 18px;
    height: 18px;
    display: grid;
    place-items: center;
    border-radius: 50%;
    background: var(--frame-remove-bg);
    color: var(--fg);
    opacity: 0;
    transition: opacity var(--dur) var(--ease), background var(--dur) var(--ease);
    cursor: pointer;
}

.frame-item:hover .frame-remove {
    opacity: 1;
}

.frame-remove:hover {
    background: #d8443c;
}

.thumbnails.is-drop-target {
    background: var(--drop-target-tint-soft);
    border-radius: var(--r-sm);
}

/* ----- Global drop overlay ------------------------------ */

.drop-overlay {
    position: fixed;
    inset: 0;
    z-index: 200;
    background: var(--scrim);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    display: grid;
    place-items: center;
    pointer-events: none;
    opacity: 0;
    transition: opacity 180ms var(--ease);
}

.drop-overlay.is-active {
    opacity: 1;
    pointer-events: auto;
}

.drop-overlay-card {
    display: grid;
    justify-items: center;
    gap: 12px;
    padding: 38px 56px;
    background: var(--scrim-card);
    border-radius: var(--r-lg);
    box-shadow: var(--shadow-lg);
    transform: scale(0.96);
    transition: transform 180ms var(--ease);
}

.drop-overlay.is-active .drop-overlay-card {
    transform: scale(1);
}

.drop-overlay-icon {
    color: var(--accent);
}

.drop-overlay-title {
    font-size: 28px;
    color: var(--fg);
    letter-spacing: -0.01em;
}

.drop-overlay-hint {
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.18em;
    color: var(--fg-mute);
}

/* ----- Loader overlay ---------------------------------- */

.loader-overlay {
    position: fixed;
    inset: 0;
    z-index: 180;
    background: var(--scrim-light);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    display: grid;
    place-items: center;
    pointer-events: none;
    opacity: 0;
    transition: opacity 180ms var(--ease);
}

.loader-overlay.is-active {
    opacity: 1;
    pointer-events: auto;
}

.loader-overlay-card {
    display: grid;
    justify-items: center;
    gap: 14px;
    padding: 32px 42px;
    background: var(--scrim-card-loader);
    border-radius: var(--r-lg);
    box-shadow: var(--shadow-lg);
    min-width: 220px;
}

.loader-spinner {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: conic-gradient(transparent 0deg, var(--accent) 80deg, var(--accent) 280deg, transparent 360deg);
    -webkit-mask: radial-gradient(circle, transparent 14px, #000 15px);
    mask: radial-gradient(circle, transparent 14px, #000 15px);
    animation: spin 0.95s linear infinite;
}

.loader-text {
    font-size: 14px;
    font-weight: 600;
    color: var(--fg);
    letter-spacing: 0.01em;
}

.loader-sub {
    font-size: 11px;
    color: var(--fg-mute);
    text-transform: uppercase;
    letter-spacing: 0.16em;
    min-height: 1em;
}