:root {
  --ink: #15151f;
  --ink-soft: #5a5a6e;
  --ink-faint: #9a9aab;
  --line: #e6e6ee;
  --bg: #f4f5f9;
  --card: #ffffff;
  --accent: #2e5bff;
  --accent-soft: #eef1ff;
  --accent-ink: #1d3bb8;
  --accent-hover: #2349d6;
  --ok: #0f9e75;
  --ok-soft: #e1f5ee;
  --danger: #d8453b;
  --danger-soft: #fbeaea;
  --danger-ink: #a3201a;
  --radius: 18px;
  --radius-sm: 12px;
  --shadow: 0 1px 2px rgba(20, 20, 40, 0.04), 0 8px 28px rgba(20, 20, 40, 0.06);
  --shadow-lg: 0 20px 50px rgba(20, 20, 40, 0.18);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body { height: 100%; }

/* hidden 属性优先级最高，避免被 display:flex/block 覆盖 */
[hidden] { display: none !important; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

button { font-family: inherit; cursor: pointer; }

.wrap {
  width: 100%;
  max-width: 600px;
  margin: 0 auto;
  padding: 32px 18px 24px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

/* ===== Language switch ===== */
.lang-switch {
  position: fixed;
  top: 14px; right: 14px;
  z-index: 100;
  display: flex; gap: 2px;
  background: #ececf3;
  padding: 3px;
  border-radius: 999px;
  box-shadow: 0 2px 6px rgba(20, 20, 40, 0.06);
}
.lang-btn {
  border: 0; background: transparent;
  padding: 5px 12px;
  font-size: 12px; font-weight: 600;
  color: var(--ink-soft);
  border-radius: 999px;
  font-family: inherit;
  transition: background .15s, color .15s;
}
.lang-btn.on { background: #fff; color: var(--ink); box-shadow: 0 1px 3px rgba(0,0,0,.08); }
.lang-btn:hover:not(.on) { color: var(--ink); }

/* ===== Brand ===== */
.brand { text-align: center; margin-bottom: 24px; }
.brand-link {
  display: inline-flex; align-items: center; gap: 10px;
  text-decoration: none; color: inherit;
}
.logo {
  width: 38px; height: 38px; border-radius: 11px; background: var(--accent);
  display: grid; place-items: center;
  box-shadow: 0 4px 12px rgba(46, 91, 255, 0.25);
}
.logo svg { width: 24px; height: 24px; display: block; }
.logo.sm { width: 26px; height: 26px; border-radius: 8px; box-shadow: none; }
.logo.sm svg { width: 16px; height: 16px; }
.brand b { font-size: 22px; letter-spacing: -0.01em; font-weight: 700; }
.tagline {
  margin-top: 8px;
  color: var(--ink-soft); font-size: 14px;
}

/* ===== Tabs ===== */
.tabs {
  display: flex; gap: 4px;
  background: #ececf3; padding: 4px; border-radius: 12px;
  margin-bottom: 18px;
}
.tab {
  flex: 1; border: 0; background: transparent;
  padding: 10px; border-radius: 9px;
  font-size: 14px; font-weight: 600; color: var(--ink-soft);
  transition: background .15s, color .15s;
}
.tab.on { background: #fff; color: var(--ink); box-shadow: 0 1px 3px rgba(0,0,0,.06); }

/* ===== Views ===== */
.view { display: none; }
.view.active { display: block; }

/* ===== Card ===== */
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow);
}

/* ===== Segmented (text/file) ===== */
.seg { display: flex; gap: 8px; margin-bottom: 16px; }
.seg-btn {
  flex: 1; border: 1px solid var(--line); background: #fff;
  border-radius: 11px; padding: 11px;
  font-size: 13.5px; font-weight: 600; color: var(--ink-soft);
  display: flex; align-items: center; justify-content: center; gap: 6px;
  transition: all .15s;
}
.seg-btn svg { width: 16px; height: 16px; }
.seg-btn.on { border-color: var(--accent); background: var(--accent-soft); color: var(--accent-ink); }
.seg-btn:hover:not(.on) { border-color: #c8cad8; }

/* ===== Panes ===== */
.pane { display: none; }
.pane.active { display: block; }

/* ===== Inputs ===== */
textarea {
  width: 100%;
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 13px;
  font-family: "SF Mono", ui-monospace, Menlo, monospace;
  font-size: 13.5px; color: var(--ink); background: #fcfcfe;
  resize: vertical; min-height: 120px;
  transition: border-color .15s;
}
textarea:focus { outline: none; border-color: var(--accent); background: #fff; }
textarea::placeholder { color: var(--ink-faint); }

.char-count {
  margin-top: 6px; text-align: right;
  font-size: 11.5px; color: var(--ink-faint);
}

/* ===== Drop zone ===== */
.drop {
  display: block;
  border: 1.5px dashed #c8cad8; border-radius: var(--radius-sm);
  padding: 30px 16px; text-align: center; color: var(--ink-soft);
  background: #fcfcfe;
  cursor: pointer;
  transition: all .15s;
}
.drop:hover, .drop.dragover {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-ink);
}
.drop svg { width: 32px; height: 32px; color: var(--ink-faint); margin-bottom: 8px; }
.drop:hover svg, .drop.dragover svg { color: var(--accent); }
.drop .big { font-size: 14px; font-weight: 500; }
.drop .small { font-size: 12px; color: var(--ink-faint); margin-top: 4px; }

.file-info {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  background: #f7f8fb; border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 13px;
}
.file-info .meta { display: flex; align-items: center; gap: 11px; min-width: 0; flex: 1; }
.fi {
  width: 38px; height: 38px; border-radius: 10px; background: var(--accent-soft);
  display: grid; place-items: center; flex: 0 0 auto;
}
.fi svg { width: 18px; height: 18px; color: var(--accent); }
.file-info .info { min-width: 0; flex: 1; }
.file-info .nm { font-size: 13px; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-info .sz { font-size: 11.5px; color: var(--ink-faint); margin-top: 2px; }

.icon-btn {
  flex: 0 0 auto;
  width: 32px; height: 32px; border-radius: 8px;
  border: 1px solid var(--line); background: #fff;
  display: grid; place-items: center;
  color: var(--ink-soft);
}
.icon-btn svg { width: 14px; height: 14px; }
.icon-btn:hover { background: var(--danger-soft); border-color: var(--danger); color: var(--danger); }

/* ===== Progress ===== */
.progress-wrap { margin-top: 14px; }
.progress { height: 6px; border-radius: 4px; background: #e9eaf2; overflow: hidden; }
.progress i { display: block; height: 100%; width: 0%; background: var(--accent); border-radius: 4px; transition: width .2s; }
.progress-lab {
  font-size: 11.5px; color: var(--ink-soft);
  margin-top: 6px;
  display: flex; justify-content: space-between;
}

/* ===== Field & Select ===== */
.field { margin-top: 16px; }
.field label {
  display: block;
  font-size: 12.5px; color: var(--ink-soft);
  margin-bottom: 7px; font-weight: 600;
}
.select {
  width: 100%;
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 11px 13px;
  font-size: 14px; background: #fcfcfe url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%239a9aab' stroke-width='2'><path d='M6 9l6 6 6-6'/></svg>") no-repeat right 12px center / 16px;
  color: var(--ink);
  appearance: none; -webkit-appearance: none;
  font-family: inherit;
}
.select:focus { outline: none; border-color: var(--accent); }

/* ===== PIN input ===== */
.pin {
  width: 100%; text-align: center;
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  font-size: 32px; letter-spacing: 0.4em;
  font-family: "SF Mono", ui-monospace, Menlo, monospace;
  font-weight: 600;
  padding: 16px 0;
  background: #fcfcfe; color: var(--ink);
  transition: border-color .15s;
}
.pin:focus { outline: none; border-color: var(--accent); background: #fff; }
.pin::placeholder { color: #cfcfdb; letter-spacing: 0.4em; }

/* ===== Buttons ===== */
.btn {
  width: 100%;
  border: 0; border-radius: var(--radius-sm); padding: 13px 16px;
  font-size: 15px; font-weight: 600;
  display: flex; align-items: center; justify-content: center; gap: 7px;
  transition: background .15s, opacity .15s;
}
.btn svg { width: 17px; height: 17px; }
.btn.primary { background: var(--accent); color: #fff; margin-top: 18px; }
.btn.primary:hover:not(:disabled) { background: var(--accent-hover); }
.btn.primary:disabled { background: #9fb2ff; cursor: not-allowed; }
.btn.ghost { background: #fff; border: 1px solid var(--line); color: var(--ink); }
.btn.ghost:hover { background: var(--bg); }
.btn.full { width: 100%; }

/* ===== Hint ===== */
.hint {
  font-size: 12px; color: var(--ink-faint);
  text-align: center; margin-top: 10px;
}

/* ===== Result ===== */
.result {
  margin-top: 16px;
  background: var(--accent-soft);
  border: 1px solid #d8e0ff;
  border-radius: var(--radius);
  padding: 22px;
  text-align: center;
  animation: pop .25s ease-out;
}
@keyframes pop { from { transform: scale(.97); opacity: 0; } to { transform: scale(1); opacity: 1; } }

.result-lab {
  font-size: 12px; color: var(--accent-ink);
  font-weight: 600; margin-bottom: 10px;
  letter-spacing: 0.04em;
}
.result-code {
  font-size: 40px; font-weight: 700; letter-spacing: 0.18em;
  color: var(--accent-ink);
  font-family: "SF Mono", ui-monospace, Menlo, monospace;
  line-height: 1.1;
}
.result-link {
  font-size: 12px; color: var(--accent);
  background: #fff; border: 1px solid #d8e0ff; border-radius: 8px;
  padding: 8px 10px; margin: 14px 0;
  word-break: break-all;
  font-family: "SF Mono", ui-monospace, Menlo, monospace;
}
.copy-row { display: flex; gap: 8px; }
.copy-row .btn { margin-top: 0; font-size: 13.5px; padding: 11px; }

/* ===== Receive box ===== */
.rx-box {
  margin-top: 18px;
  border-top: 1px dashed var(--line);
  padding-top: 18px;
}
.rx-status {
  font-size: 13.5px; font-weight: 600;
  display: flex; align-items: center; gap: 6px;
  margin-bottom: 12px;
}
.rx-status.ok { color: var(--ok); }
.rx-status.err { color: var(--danger); }
.rx-status svg { width: 16px; height: 16px; }

.rx-text {
  background: #f7f8fb; border: 1px solid var(--line);
  border-radius: var(--radius-sm); padding: 13px;
  font-family: "SF Mono", ui-monospace, Menlo, monospace;
  font-size: 13px; color: var(--ink);
  white-space: pre-wrap; word-break: break-word;
  max-height: 320px; overflow: auto;
}

.rx-file {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  background: #f7f8fb; border: 1px solid var(--line);
  border-radius: var(--radius-sm); padding: 13px;
}
.rx-file .meta { display: flex; align-items: center; gap: 11px; min-width: 0; }
.rx-file .nm { font-size: 13px; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.rx-file .sz { font-size: 11.5px; color: var(--ink-faint); margin-top: 2px; }
.dl {
  flex: 0 0 auto;
  background: var(--accent); color: #fff; border: 0; border-radius: 9px;
  padding: 9px 14px; font-size: 13px; font-weight: 600;
  display: flex; align-items: center; gap: 5px;
  text-decoration: none;
}
.dl:hover { background: var(--accent-hover); }
.dl svg { width: 14px; height: 14px; }

.burn-warn {
  margin-top: 10px;
  font-size: 11.5px; color: var(--danger);
  background: var(--danger-soft); border: 1px solid #f3cfcf;
  border-radius: 8px; padding: 8px 10px;
  display: flex; align-items: center; gap: 6px;
}
.burn-warn svg { width: 13px; height: 13px; flex: 0 0 auto; }

/* ===== Error box ===== */
.err-box {
  background: var(--danger-soft); border: 1px solid #f3cfcf;
  border-radius: var(--radius-sm); padding: 13px;
  font-size: 13.5px; color: var(--danger-ink);
  display: flex; align-items: flex-start; gap: 8px;
  margin-top: 14px;
}
.err-box svg { width: 16px; height: 16px; flex: 0 0 auto; margin-top: 2px; }

/* ===== Footer ===== */
.footer {
  margin-top: 32px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.foot-row {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; flex-wrap: wrap;
}
.foot-brand {
  display: flex; align-items: center; gap: 9px;
  font-size: 13px; color: var(--ink-soft);
}
.donate-btn {
  display: flex; align-items: center; gap: 6px;
  background: #fff; border: 1px solid var(--line); border-radius: 10px;
  padding: 8px 14px;
  font-size: 13px; color: var(--accent-ink); font-weight: 500;
  transition: all .15s;
}
.donate-btn:hover { border-color: var(--accent); background: var(--accent-soft); }
.donate-btn svg { width: 15px; height: 15px; }
.foot-meta {
  margin-top: 14px;
  font-size: 11.5px; color: var(--ink-faint);
  text-align: center;
}

/* ===== Modal ===== */
.modal {
  position: fixed; inset: 0;
  z-index: 1000;
  display: flex; align-items: center; justify-content: center;
  padding: 20px;
  animation: fadeIn .15s;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.modal-bg {
  position: absolute; inset: 0;
  background: rgba(20, 20, 40, 0.55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}
.modal-card {
  position: relative;
  background: #fff; border-radius: 22px;
  padding: 28px 24px 22px;
  width: 100%; max-width: 280px;
  text-align: center;
  box-shadow: var(--shadow-lg);
  animation: pop .2s ease-out;
}
.modal-close {
  position: absolute; top: 12px; right: 12px;
  width: 30px; height: 30px; border-radius: 8px;
  border: 0; background: transparent;
  display: grid; place-items: center;
  color: var(--ink-faint);
}
.modal-close:hover { background: var(--bg); color: var(--ink); }
.modal-close svg { width: 16px; height: 16px; }

.donate-title { font-size: 16px; font-weight: 700; color: var(--ink); }
.donate-sub { font-size: 12px; color: var(--ink-faint); margin: 4px 0 18px; }
.qr-box {
  width: 200px; height: 200px; margin: 0 auto;
  border: 1px solid var(--line); border-radius: 14px;
  display: grid; place-items: center; background: #fcfcfe;
  padding: 12px;
}
.qr-box svg,
.qr-box img { width: 100%; height: 100%; object-fit: contain; display: block; }
.donate-foot { font-size: 12px; color: var(--ink-soft); margin-top: 14px; }

/* ===== Toast ===== */
.toast {
  position: fixed; bottom: 28px; left: 50%;
  transform: translateX(-50%);
  background: rgba(20, 20, 40, 0.92); color: #fff;
  padding: 10px 18px; border-radius: 10px;
  font-size: 13.5px; font-weight: 500;
  z-index: 2000;
  box-shadow: var(--shadow);
  animation: slideUp .2s ease-out;
}
@keyframes slideUp { from { transform: translate(-50%, 10px); opacity: 0; } to { transform: translate(-50%, 0); opacity: 1; } }

/* ===== Mobile（≤ 480px）：尽量占满视口，留小内边距 ===== */
@media (max-width: 480px) {
  .wrap { padding: 20px 12px 18px; max-width: 100%; }
  .brand b { font-size: 20px; }
  .tagline { font-size: 13px; }
  .card { padding: 18px; }
  .result-code { font-size: 32px; }
  .pin { font-size: 26px; padding: 14px 0; letter-spacing: 0.35em; }
  .foot-row { gap: 10px; flex-direction: column; align-items: stretch; }
  .foot-brand { justify-content: center; font-size: 12.5px; }
  .donate-btn { justify-content: center; }
}

/* ===== 小平板 / 大手机（481–767px）：略放宽容器 ===== */
@media (min-width: 481px) and (max-width: 767px) {
  .wrap { max-width: 560px; padding: 28px 20px 22px; }
}

/* ===== 平板 / 桌面（768–1199px）：更舒展 ===== */
@media (min-width: 768px) {
  .wrap { max-width: 680px; padding: 48px 24px 28px; }
  .brand { margin-bottom: 32px; }
  .brand b { font-size: 24px; }
  .logo { width: 42px; height: 42px; border-radius: 12px; }
  .logo svg { width: 26px; height: 26px; }
  .tagline { font-size: 15px; }
  .card { padding: 28px; }
  textarea { min-height: 140px; font-size: 14px; }
  .pin { font-size: 36px; padding: 18px 0; }
  .result-code { font-size: 44px; }
  .btn.primary { padding: 14px 18px; font-size: 15.5px; }
}

/* ===== 宽屏桌面（≥ 1200px）：再宽一档 ===== */
@media (min-width: 1200px) {
  .wrap { max-width: 760px; padding-top: 64px; }
  .card { padding: 32px; }
  textarea { min-height: 160px; }
}

/* ===== Reduced motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}