:root {
    --bg: #0b1220;
    --bg-elev: #0f172a;
    --panel: #111a2e;
    --panel-2: #17223b;
    --border: #1f2a44;
    --text: #e6edf7;
    --text-dim: #9aa7bd;
    --accent: #38bdf8;
    --accent-2: #0ea5e9;
    --accent-3: #22d3ee;
    --danger: #f87171;
    --promo-bg: linear-gradient(90deg, #0ea5e9 0%, #6366f1 60%, #a855f7 100%);
    --stroke: #cbd5e1;
    --canvas-bg: #0b1220;
    --canvas-grid: rgba(148, 163, 184, 0.08);
    --canvas-grid-strong: rgba(148, 163, 184, 0.15);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

:root.light {
    --bg: #f8fafc;
    --bg-elev: #ffffff;
    --panel: #ffffff;
    --panel-2: #f1f5f9;
    --border: #e2e8f0;
    --text: #0f172a;
    --text-dim: #475569;
    --accent: #0284c7;
    --accent-2: #0369a1;
    --accent-3: #0891b2;
    --stroke: #0f172a;
    --canvas-bg: #ffffff;
    --canvas-grid: rgba(15, 23, 42, 0.06);
    --canvas-grid-strong: rgba(15, 23, 42, 0.12);
    --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    background: var(--bg);
    color: var(--text);
    font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    display: flex;
    flex-direction: column;
    min-height: 100dvh;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 20px;
    border-bottom: 1px solid var(--border);
    background: var(--bg-elev);
    position: sticky;
    top: 0;
    z-index: 10;
    padding-top: max(14px, env(safe-area-inset-top));
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 0;
}

.logo {
    display: grid;
    place-items: center;
    width: 38px;
    height: 38px;
    border-radius: 10px;
    background: linear-gradient(135deg, var(--accent-2), var(--accent-3));
    color: white;
    box-shadow: var(--shadow);
    flex: none;
}

.brand-text { min-width: 0; }

.brand h1 {
    margin: 0;
    font-size: 16px;
    font-weight: 700;
    letter-spacing: -0.01em;
}

.brand p {
    margin: 2px 0 0;
    color: var(--text-dim);
    font-size: 12px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 60ch;
}

.topbar-actions {
    display: flex;
    gap: 8px;
    flex: none;
}

.promo {
    position: relative;
    padding: 10px 16px;
    background: var(--promo-bg);
    color: white;
    font-size: 14px;
    box-shadow: inset 0 -1px 0 rgba(0,0,0,0.12);
}

.promo-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px 14px;
}

.promo-badge {
    display: inline-block;
    background: rgba(0, 0, 0, 0.25);
    padding: 2px 8px;
    border-radius: 999px;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.promo-text {
    margin: 0;
    flex: 1 1 auto;
    min-width: 0;
    line-height: 1.45;
}

.promo-text a { color: white; text-decoration: underline; font-weight: 600; }

.promo-cta {
    color: white;
    background: rgba(0, 0, 0, 0.22);
    border: 1px solid rgba(255, 255, 255, 0.35);
    padding: 6px 12px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 13px;
    flex: none;
    white-space: nowrap;
}

.promo-cta:hover { background: rgba(0, 0, 0, 0.35); text-decoration: none; }

main {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    padding: 20px;
    gap: 16px;
    max-width: 1400px;
    width: 100%;
    margin: 0 auto;
}

.dropzone {
    flex: 1;
    min-height: 50vh;
    border: 2px dashed var(--border);
    border-radius: 18px;
    display: grid;
    place-items: center;
    cursor: pointer;
    background:
        radial-gradient(900px 380px at 50% -10%, rgba(56, 189, 248, 0.12), transparent 60%),
        var(--panel);
    transition: border-color 160ms ease, background-color 160ms ease, transform 160ms ease;
    padding: 24px;
    text-align: center;
    outline: none;
}

.dropzone:hover, .dropzone:focus-visible { border-color: var(--accent); }
.dropzone.dragover {
    border-color: var(--accent);
    background: var(--panel-2);
    transform: scale(1.005);
}

.dropzone-inner { max-width: 520px; }
.dropzone-icon { color: var(--accent); margin-bottom: 12px; }
.dropzone h2 { margin: 0 0 6px; font-size: 22px; font-weight: 700; letter-spacing: -0.01em; }
.dropzone p { margin: 4px 0; color: var(--text-dim); }
.dropzone .hint { margin-top: 14px; font-size: 13px; color: var(--text-dim); }

.linkish {
    background: none;
    border: 0;
    color: var(--accent);
    cursor: pointer;
    font: inherit;
    padding: 0;
    text-decoration: underline;
}

.viewer {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.viewer:fullscreen,
.viewer:-webkit-full-screen,
.viewer.is-fullscreen {
    width: 100vw;
    height: 100vh;
    max-width: none;
    max-height: none;
    border-radius: 0;
    border: 0;
    box-shadow: none;
    background: var(--canvas-bg);
}

.viewer-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 14px;
    border-bottom: 1px solid var(--border);
    background: var(--panel-2);
    gap: 12px;
    flex-wrap: wrap;
}

.file-meta { display: flex; flex-direction: column; min-width: 0; flex: 1 1 auto; }
.file-name {
    font-weight: 600;
    font-size: 14px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 60ch;
}
.file-stats { font-size: 12px; color: var(--text-dim); }

.tools { display: flex; gap: 6px; flex-wrap: wrap; }

.btn {
    border: 1px solid var(--border);
    background: var(--panel);
    color: var(--text);
    padding: 8px 12px;
    font-size: 13px;
    border-radius: 10px;
    cursor: pointer;
    font-family: inherit;
    transition: background-color 120ms ease, border-color 120ms ease, transform 80ms ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.btn:hover { background: var(--panel-2); border-color: var(--accent); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-ghost { background: transparent; }
.btn-icon { width: 38px; height: 38px; padding: 0; }
.btn.is-active {
    background: color-mix(in oklab, var(--accent) 28%, var(--panel));
    border-color: var(--accent);
    color: var(--text);
}

.file-tabs {
    display: flex;
    gap: 2px;
    padding: 6px 8px 0;
    overflow-x: auto;
    border-bottom: 1px solid var(--border);
    background: var(--panel-2);
    scrollbar-width: thin;
    align-items: flex-end;
}

.file-tab {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 8px 8px 12px;
    border-radius: 8px 8px 0 0;
    background: transparent;
    border: 1px solid transparent;
    border-bottom: none;
    font-size: 12px;
    flex: none;
    max-width: 260px;
    cursor: pointer;
    color: var(--text-dim);
    position: relative;
    top: 1px;
    transition: background-color 120ms ease, color 120ms ease;
    font-family: inherit;
}

.file-tab:hover { background: color-mix(in oklab, var(--panel) 60%, var(--panel-2)); color: var(--text); }

.file-tab.active {
    background: var(--panel);
    border-color: var(--border);
    color: var(--text);
}

.file-tab.active::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -1px;
    height: 1px;
    background: var(--panel);
}

.file-tab .swatch {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    flex: none;
    box-shadow: 0 0 0 1px rgba(0,0,0,0.25) inset;
}

.file-tab .tab-name {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    font-weight: 600;
    max-width: 20ch;
}

.file-tab .tab-count {
    color: var(--text-dim);
    font-variant-numeric: tabular-nums;
    font-size: 11px;
}

.file-tab .tab-close {
    background: transparent;
    border: 0;
    color: var(--text-dim);
    cursor: pointer;
    padding: 3px;
    border-radius: 6px;
    line-height: 0;
    display: inline-flex;
    margin-left: 2px;
}

.file-tab .tab-close:hover { background: color-mix(in oklab, var(--text) 15%, transparent); color: var(--text); }

.canvas-wrap {
    position: relative;
    flex: 1;
    min-height: 0;
    background:
        linear-gradient(var(--canvas-grid) 1px, transparent 1px) 0 0/20px 20px,
        linear-gradient(90deg, var(--canvas-grid) 1px, transparent 1px) 0 0/20px 20px,
        var(--canvas-bg);
    overflow: hidden;
    touch-action: none;
}

#canvas {
    width: 100%;
    height: 100%;
    display: block;
    cursor: grab;
}

#canvas.grabbing { cursor: grabbing; }

.canvas-wrap.measure-mode #canvas { cursor: crosshair; }
.canvas-wrap.measure-mode #canvas.grabbing { cursor: grabbing; }

.hud {
    position: absolute;
    left: 12px;
    bottom: 12px;
    background: color-mix(in oklab, var(--panel) 85%, transparent);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 6px 10px;
    font-size: 12px;
    color: var(--text-dim);
    pointer-events: none;
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
}

.loading {
    position: absolute;
    inset: 0;
    display: grid;
    place-items: center;
    background: color-mix(in oklab, var(--panel) 80%, transparent);
    backdrop-filter: blur(2px);
}

.loading p { margin-top: 14px; color: var(--text-dim); }

.spinner {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: 3px solid var(--border);
    border-top-color: var(--accent);
    animation: spin 900ms linear infinite;
    margin: 0 auto;
}

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

.error-panel {
    background: color-mix(in oklab, var(--danger) 18%, var(--panel));
    border: 1px solid color-mix(in oklab, var(--danger) 40%, var(--border));
    color: var(--text);
    padding: 14px 16px;
    border-radius: 12px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    align-items: flex-start;
}

.error-panel p { margin: 0; color: var(--text); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 13px; word-break: break-word; }
.error-panel .error-hint { color: var(--text-dim); font-family: inherit; font-size: 12px; }

.footer {
    text-align: center;
    padding: 14px 16px;
    border-top: 1px solid var(--border);
    color: var(--text-dim);
    font-size: 12px;
    padding-bottom: max(14px, env(safe-area-inset-bottom));
}

.footer p { margin: 0; }

@media (max-width: 640px) {
    .brand p { display: none; }
    .brand h1 { font-size: 15px; }
    main { padding: 12px; }
    .promo { font-size: 13px; padding: 10px 12px; }
    .promo-cta { padding: 5px 10px; font-size: 12px; }
    .viewer-toolbar { padding: 8px 10px; }
    .btn { padding: 7px 10px; font-size: 12px; }
    .btn-icon { width: 36px; height: 36px; }
    .dropzone h2 { font-size: 18px; }
}

@media (prefers-reduced-motion: reduce) {
    * { transition: none !important; animation-duration: 0.001ms !important; }
}