:root {
  --ink: #16181d;
  --ink-soft: #5b616e;
  --line: rgba(0, 0, 0, .11);
  --fill: rgba(0, 0, 0, .045);
  --fill-hover: rgba(0, 0, 0, .09);
  --card: #fff;
  --page: #eef0f3;
  --accent: #16181d;
  --accent-hover: #000;
  --ok: #2f7a56;
  --warn: #9a6708;
  --err: #b4342a;
  --radius: 12px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

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

body {
  margin: 0;
  padding: 24px 16px 0;
  background: var(--page);
  font: 15px/1.55 system-ui, -apple-system, "Segoe UI", "Microsoft JhengHei",
        "PingFang TC", "Noto Sans TC", sans-serif;
  color: var(--ink);
}

.noscript {
  max-width: 900px;
  margin: 0 auto 16px;
  padding: 14px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
}

/* ---------- 版面 ---------- */

.app {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 340px);
  gap: 16px;
  align-items: start;
  max-width: 900px;
  margin: 0 auto;
}

.pane {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--card);
  box-shadow: 0 1px 2px rgba(0, 0, 0, .04), 0 8px 24px rgba(0, 0, 0, .05);
}

.pane--preview {
  position: sticky;
  top: 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.head { margin-bottom: 18px; }

.head__title {
  margin: 0;
  font-size: 16px;
  font-weight: 650;
  letter-spacing: .02em;
}

.group + .group { margin-top: 22px; padding-top: 20px; border-top: 1px solid var(--line); }

.group__title {
  margin: 0 0 12px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-soft);
  letter-spacing: .04em;
}

/* ---------- 表單 ---------- */

.field { margin-top: 14px; }
.field:first-of-type { margin-top: 12px; }

.field.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }

label {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
  color: var(--ink-soft);
}

label output, label .lock { font-family: var(--mono); font-size: 12.5px; color: var(--ink); }
label .lock { font-family: inherit; color: var(--warn); }

input[type="text"], input[type="url"], textarea, select {
  width: 100%;
  padding: 9px 11px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  font: inherit;
  color: inherit;
}

textarea { resize: vertical; line-height: 1.6; }

input[type="text"]:focus, input[type="url"]:focus, textarea:focus, select:focus {
  outline: none;
  border-color: #2b7cff;
  box-shadow: 0 0 0 3px rgba(43, 124, 255, .13);
}

.field label + label { margin-top: 12px; }

.check {
  display: flex;
  align-items: center;
  gap: 7px;
  margin-top: 10px;
  color: var(--ink);
  font-size: 14px;
  cursor: pointer;
}

.check input { margin: 0; }

.hint {
  margin: 6px 0 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--ink-soft);
}

.hint code {
  padding: 1px 4px;
  border-radius: 4px;
  background: var(--fill);
  font-family: var(--mono);
  font-size: 11.5px;
}

.capacity {
  margin: 12px 0 0;
  font-size: 12.5px;
  color: var(--ink-soft);
}

.capacity.over { color: var(--err); font-weight: 600; }

/* ---------- 顏色 ---------- */

.color-pair { display: flex; gap: 6px; }

input[type="color"] {
  flex: 0 0 42px;
  height: 38px;
  padding: 2px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  cursor: pointer;
}

input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
input[type="color"]::-webkit-color-swatch { border: 0; border-radius: 7px; }
input[type="color"]::-moz-color-swatch { border: 0; border-radius: 7px; }

.color-pair input[type="text"] {
  min-width: 0;
  font-family: var(--mono);
  font-size: 13px;
  text-transform: lowercase;
}

/* ---------- 滑桿 ---------- */

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

input[type="range"]::-webkit-slider-runnable-track {
  height: 6px; border-radius: 3px; background: var(--fill-hover);
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px; height: 18px; margin-top: -6px;
  border-radius: 50%; background: #fff;
  border: 1px solid rgba(0, 0, 0, .2);
  box-shadow: 0 1px 4px rgba(0, 0, 0, .2);
}
input[type="range"]::-moz-range-track {
  height: 6px; border-radius: 3px; background: var(--fill-hover);
}
input[type="range"]::-moz-range-thumb {
  width: 18px; height: 18px; border-radius: 50%; background: #fff;
  border: 1px solid rgba(0, 0, 0, .2);
  box-shadow: 0 1px 4px rgba(0, 0, 0, .2);
}

/* ---------- 按鈕與分段控制 ---------- */

button { font: inherit; color: inherit; cursor: pointer; }

.seg {
  display: flex;
  gap: 3px;
  padding: 3px;
  border-radius: var(--radius);
  background: var(--fill);
}

.seg button {
  flex: 1;
  padding: 8px 4px;
  border: 0;
  border-radius: 9px;
  background: transparent;
  color: var(--ink-soft);
  font-weight: 550;
  transition: background .15s, color .15s;
}

.seg button:hover:not(.is-active):not(:disabled) { background: rgba(255, 255, 255, .7); }

.seg button.is-active {
  background: #fff;
  color: var(--ink);
  box-shadow: 0 1px 3px rgba(0, 0, 0, .12);
}

.seg button:disabled { opacity: .4; cursor: not-allowed; }
.seg--sm button { padding: 6px 2px; font-size: 13px; }

.ghost, .primary {
  padding: 9px 16px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: #fff;
  font-weight: 550;
  transition: background .15s, transform .1s, border-color .15s;
}

.ghost:hover { border-color: rgba(0, 0, 0, .2); background: #fafafa; }
.ghost:active, .primary:active { transform: translateY(1px); }
.danger:hover { color: var(--err); border-color: rgba(180, 52, 42, .4); }

.primary {
  flex: 1;
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: 600;
}

.primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
.primary.done { background: var(--ok); border-color: var(--ok); }

button:disabled { opacity: .4; cursor: not-allowed; transform: none; }

:focus-visible { outline: 2px solid #2b7cff; outline-offset: 2px; }

/* ---------- Logo ---------- */

.logo-row { display: flex; align-items: center; gap: 8px; }

.pos-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-top: 12px;
  font-size: 13px;
  color: var(--ink-soft);
}

.pos-row output { font-family: var(--mono); font-size: 12.5px; color: var(--ink); }

.ghost--sm { padding: 5px 10px; font-size: 13px; }

.pos-presets {
  display: grid;
  grid-template-columns: repeat(3, 40px);
  gap: 4px;
  margin-top: 8px;
}

.pos-presets button {
  height: 34px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  font-size: 14px;
  color: var(--ink-soft);
  transition: background .15s, color .15s, border-color .15s;
}

.pos-presets button:hover:not(:disabled) { background: #f6f7f8; color: var(--ink); border-color: rgba(0, 0, 0, .2); }
.pos-presets button.is-active { background: var(--accent); border-color: var(--accent); color: #fff; }
.pos-presets button:disabled { opacity: .3; cursor: not-allowed; }

#logo-thumb {
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 8px;
  object-fit: contain;
  background: var(--fill);
}

/* ---------- 預覽 ---------- */

.preview { text-align: center; }

#preview-canvas {
  width: 100%;
  max-width: 280px;
  height: auto;
  border-radius: 10px;
  box-shadow: 0 0 0 1px var(--line);
  image-rendering: pixelated;
}

/* 有 logo 且安全區塞得下時才可拖曳 */
#preview-canvas.draggable { cursor: grab; touch-action: none; }
#preview-canvas.draggable:active { cursor: grabbing; }

.preview__meta {
  margin: 10px 0 0;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-soft);
}

/* ---------- 檢查結果 ---------- */

.checks { display: flex; flex-direction: column; gap: 7px; }

.chk {
  display: flex;
  gap: 8px;
  align-items: baseline;
  font-size: 13px;
  line-height: 1.6;
}

.chk__icon { flex: 0 0 auto; font-weight: 700; }
.chk--ok   .chk__icon { color: var(--ok); }
.chk--warn .chk__icon { color: var(--warn); }
.chk--err  .chk__icon { color: var(--err); }
.chk--wait .chk__icon { color: var(--ink-soft); }
.chk--warn { color: var(--warn); }
.chk--err  { color: var(--err); }

.chk__note { color: var(--ink-soft); }

/* ---------- 匯出 ---------- */

.export {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.export__row { display: flex; align-items: center; gap: 8px; }
.export__row label { margin: 0; flex: 0 0 auto; }
.export__row select { width: auto; flex: 1; }

/* ---------- 說明內容 ---------- */

.content {
  max-width: 900px;
  margin: 22px auto;
  padding: 30px 36px 38px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--card);
}

.content h1 { margin: 0 0 12px; font-size: 26px; font-weight: 680; }
.content .lead { margin: 0 0 26px; font-size: 16px; line-height: 1.85; color: #3d434e; }

.content h2 {
  margin: 32px 0 12px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  font-size: 19px;
  font-weight: 660;
}

.content h3 { margin: 22px 0 8px; font-size: 15.5px; font-weight: 640; }
.content p { margin: 0 0 12px; line-height: 1.85; }
.content ul { margin: 0; padding-left: 22px; }
.content li { margin-bottom: 8px; line-height: 1.8; }

.foot { max-width: 900px; margin: 0 auto; padding: 0 4px 40px; }
.foot p { margin: 0; font-size: 12.5px; line-height: 1.8; color: var(--ink-soft); }
.foot a { color: var(--ink-soft); }

/* ---------- 提示訊息 ---------- */

#toast {
  position: fixed;
  left: 50%;
  bottom: 28px;
  z-index: 5;
  transform: translate(-50%, 12px);
  padding: 10px 18px;
  border-radius: 999px;
  background: rgba(22, 24, 29, .93);
  color: #fff;
  font-size: 13.5px;
  opacity: 0;
  pointer-events: none;
  transition: opacity .2s, transform .2s;
}

#toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 窄螢幕 ---------- */

@media (max-width: 860px) {
  .app { grid-template-columns: 1fr; }
  .pane--preview { position: static; order: -1; }
  #preview-canvas { max-width: 220px; }
}

@media (max-width: 520px) {
  body { padding: 14px 12px 0; }
  .pane { padding: 16px; border-radius: 14px; }
  .content { padding: 24px 20px 30px; border-radius: 14px; margin: 16px auto; }
  .content h1 { font-size: 23px; }
  .content h2 { font-size: 18px; }
  .field.row2 { grid-template-columns: 1fr; }
}

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