:root {
  --bg: #f6f7fb; --panel: #ffffff; --ink: #161a23; --muted: #5b6474; --line: #e2e6ee; --soft: #eef1f7;
  --accent: #3657d6; --accent-ink: #ffffff; --accent-soft: #e6ecff; --error: #b42318; --ok: #157347;
  --check1: #ffffff; --check2: #e9ecf2; --shadow: 0 1px 2px rgba(16, 24, 40, .06), 0 4px 16px rgba(16, 24, 40, .06);
  --radius: 14px;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #0f1218; --panel: #171b23; --ink: #e9edf5; --muted: #9aa4b5; --line: #2a303c; --soft: #1f2430;
  --accent: #7d97ff; --accent-ink: #0b0f1a; --accent-soft: #232b45; --error: #ff8a80; --ok: #6fd39b;
  --check1: #222733; --check2: #2b3140; --shadow: 0 1px 2px rgba(0, 0, 0, .4), 0 6px 20px rgba(0, 0, 0, .3);
  color-scheme: dark;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg); color: var(--ink);
  font: 15px/1.5 Inter, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); }
.hidden { display: none !important; }

.topbar {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 20px; border-bottom: 1px solid var(--line); background: var(--panel);
  position: sticky; top: 0; z-index: 10;
}
.brand { display: flex; align-items: center; gap: 8px; min-width: 0; white-space: nowrap; overflow: hidden; }
.brand strong { overflow: hidden; text-overflow: ellipsis; }
.backlink { text-decoration: none; color: var(--muted); }
.backlink:hover { color: var(--ink); }
.sep { color: var(--line); }
.topactions { display: flex; align-items: center; gap: 10px; }
.freebadge { font-size: 13px; color: var(--ok); background: color-mix(in srgb, var(--ok) 12%, transparent); padding: 3px 10px; border-radius: 999px; white-space: nowrap; }

.wrap { max-width: 1240px; margin: 0 auto; padding: 18px 20px 40px; }
.hero h1 { margin: 6px 0 4px; font-size: 28px; letter-spacing: -0.02em; }
.lede { margin: 0 0 16px; color: var(--muted); }

.layout {
  display: grid; gap: 16px;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  grid-template-areas: "input preview" "controls preview";
  align-items: start;
}
.inputpanel { grid-area: input; }
.previewpanel { grid-area: preview; position: sticky; top: 64px; }
.controls { grid-area: controls; }
@media (max-width: 900px) {
  .layout { grid-template-columns: minmax(0, 1fr); grid-template-areas: "input" "preview" "controls"; }
  .previewpanel { position: static; }
  .freebadge { display: none; }
}

.panel { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; box-shadow: var(--shadow); min-width: 0; }

.tabs { display: flex; gap: 4px; background: var(--soft); padding: 4px; border-radius: 10px; margin-bottom: 14px; }
.tab { flex: 1; border: 0; background: transparent; color: var(--muted); padding: 8px 6px; border-radius: 8px; font: inherit; font-weight: 600; cursor: pointer; }
.tab[aria-selected="true"] { background: var(--panel); color: var(--ink); box-shadow: var(--shadow); }
.tab:focus-visible, button:focus-visible, select:focus-visible, input:focus-visible, textarea:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.field { display: flex; flex-direction: column; gap: 4px; margin-bottom: 10px; min-width: 0; }
.field > span { font-size: 13px; color: var(--muted); font-weight: 600; display: flex; justify-content: space-between; gap: 6px; }
.field output { font-weight: 500; color: var(--ink); font-variant-numeric: tabular-nums; }
.field.compact { margin-bottom: 4px; }
input[type="text"], input[type="search"], textarea, select {
  width: 100%; font: inherit; color: var(--ink); background: var(--panel);
  border: 1px solid var(--line); border-radius: 9px; padding: 9px 11px;
}
textarea { resize: vertical; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 14px; }
#smiles { font-size: 15px; }
input[type="range"] { width: 100%; accent-color: var(--accent); }
input[type="color"] { width: 100%; height: 36px; padding: 2px; border: 1px solid var(--line); border-radius: 9px; background: var(--panel); cursor: pointer; }
.check { display: flex; align-items: center; gap: 8px; font-size: 14px; cursor: pointer; min-height: 36px; }
.check input[type="color"] { width: 44px; height: 28px; }
.hint { color: var(--muted); font-size: 13px; margin: 6px 0; }
.error { color: var(--error); font-size: 14px; margin: 6px 0; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; white-space: pre-wrap; overflow-wrap: anywhere; }

button { font: inherit; cursor: pointer; }
.primary, .ghost, .chip, .filebtn {
  border-radius: 9px; padding: 8px 14px; font-weight: 600; border: 1px solid transparent; min-height: 38px;
}
.primary { background: var(--accent); color: var(--accent-ink); }
.primary:hover:not(:disabled) { filter: brightness(1.07); }
.primary:disabled { opacity: .45; cursor: not-allowed; }
.ghost { background: var(--panel); color: var(--ink); border-color: var(--line); }
.ghost:hover { background: var(--soft); }
.small { padding: 6px 10px; min-height: 32px; font-size: 13px; }
.iconbtn { width: 38px; padding: 0; font-size: 18px; }
.chip { background: var(--soft); color: var(--ink); padding: 5px 12px; min-height: 32px; font-size: 13px; border-color: var(--line); border-radius: 999px; }
.chip:hover { background: var(--accent-soft); border-color: var(--accent); }
.chip.active { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.filebtn { display: inline-flex; align-items: center; background: var(--panel); border-color: var(--line); color: var(--ink); cursor: pointer; position: relative; overflow: hidden; }
.filebtn:hover { background: var(--soft); }
.filebtn input { position: absolute; inset: 0; opacity: 0; cursor: pointer; }
.row { display: flex; align-items: center; gap: 8px; }
.wrapgap { flex-wrap: wrap; margin: 8px 0; }
.examples, .presets { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; margin-top: 12px; }
.presets { margin: 0 0 12px; }
.exlabel { font-size: 13px; color: var(--muted); margin-right: 2px; }

.results { display: flex; flex-direction: column; gap: 2px; max-height: 260px; overflow: auto; }
.result {
  display: flex; justify-content: space-between; gap: 10px; text-align: left; border: 0; background: transparent;
  color: var(--ink); padding: 7px 10px; border-radius: 8px;
}
.result:hover, .result[aria-selected="true"] { background: var(--accent-soft); }
.result small { color: var(--muted); font-variant-numeric: tabular-nums; white-space: nowrap; }

.drop {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 4px; text-align: center;
  border: 2px dashed var(--line); border-radius: 12px; padding: 26px 14px; cursor: pointer; position: relative; color: var(--muted);
}
.drop strong { color: var(--ink); }
.drop.over { border-color: var(--accent); background: var(--accent-soft); }
.drop input { position: absolute; inset: 0; opacity: 0; cursor: pointer; }

.previewbox {
  position: relative; border-radius: 12px; overflow: hidden; border: 1px solid var(--line);
  background-color: var(--check1);
  background-image: linear-gradient(45deg, var(--check2) 25%, transparent 25%), linear-gradient(-45deg, var(--check2) 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, var(--check2) 75%), linear-gradient(-45deg, transparent 75%, var(--check2) 75%);
  background-size: 20px 20px; background-position: 0 0, 0 10px, 10px -10px, -10px 0;
  aspect-ratio: 1 / 1; max-width: 560px; margin: 0 auto;
}
.preview { width: 100%; height: 100%; display: flex; align-items: center; justify-content: center; touch-action: pan-y; }
.preview svg { width: 100%; height: 100%; display: block; }
.preview.draggable { cursor: grab; touch-action: none; }
.preview .empty { color: var(--muted); padding: 20px; text-align: center; }
.draghint { position: absolute; right: 10px; bottom: 8px; margin: 0; font-size: 12px; color: var(--muted); background: var(--panel); padding: 2px 8px; border-radius: 999px; opacity: .9; }
.molinfo { text-align: center; color: var(--muted); font-size: 14px; margin: 10px 0 6px; min-height: 21px; overflow-wrap: anywhere; }
.molinfo b { color: var(--ink); }
.exportrow { display: flex; flex-wrap: wrap; gap: 6px; align-items: flex-end; justify-content: center; }
.exportrow .field { width: 110px; margin: 0; }

.group { border-top: 1px solid var(--line); padding: 4px 0; }
.group summary { cursor: pointer; font-weight: 700; padding: 10px 0; list-style-position: inside; }
.group[open] summary { margin-bottom: 6px; }
.grid2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px 14px; align-items: end; }
@media (max-width: 520px) { .grid2 { grid-template-columns: minmax(0, 1fr); } .hero h1 { font-size: 24px; } .wrap { padding: 14px 16px 32px; } .topbar { padding: 10px 16px; } }
.seg { display: flex; flex-wrap: wrap; gap: 4px; background: var(--soft); padding: 4px; border-radius: 10px; margin-bottom: 8px; }
.seg label { flex: 1 1 auto; text-align: center; padding: 7px 10px; border-radius: 8px; cursor: pointer; font-weight: 600; font-size: 14px; color: var(--muted); position: relative; }
.seg input { position: absolute; opacity: 0; pointer-events: none; }
.seg label:has(input:checked) { background: var(--panel); color: var(--ink); box-shadow: var(--shadow); }
.seg label:has(input:focus-visible) { outline: 2px solid var(--accent); }

.elements { display: flex; flex-direction: column; gap: 6px; }
.elrow { display: grid; grid-template-columns: 44px 52px minmax(0, 1fr) 84px 32px; gap: 8px; align-items: center; }
.elrow .sym { font-weight: 700; text-align: center; font-size: 15px; }
.elrow input[type="color"] { height: 32px; }
.elrow input[type="text"], .elrow input[type="number"] { padding: 6px 8px; width: 100%; font: inherit; color: var(--ink); background: var(--panel); border: 1px solid var(--line); border-radius: 8px; }
.elrow .count { color: var(--muted); font-size: 12px; text-align: right; }

.batchgrid { display: grid; grid-template-columns: repeat(auto-fill, minmax(92px, 1fr)); gap: 8px; margin: 8px 0; max-height: 420px; overflow: auto; }
.bitem { border: 1px solid var(--line); border-radius: 10px; padding: 4px; text-align: center; font-size: 12px; background: var(--panel); cursor: pointer; color: var(--ink); }
.bitem:hover { border-color: var(--accent); }
.bitem svg { width: 100%; height: auto; display: block; }
.bitem .bname { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; margin-top: 2px; }
.bitem.bad { border-color: var(--error); color: var(--error); cursor: default; }
.bitem.bad .berr { display: block; font-size: 11px; padding: 6px 2px; overflow-wrap: anywhere; }

.footer { max-width: 1240px; margin: 0 auto; padding: 8px 20px 40px; color: var(--muted); font-size: 13px; }