@font-face {
  font-family: Inter;
  font-style: normal;
  font-display: swap;
  font-weight: 100 900;
  src: url("inter-cyrillic-ext-wght-normal.woff2") format('woff2-variations');
  unicode-range: U+0460-052F,U+1C80-1C8A,U+20B4,U+2DE0-2DFF,U+A640-A69F,U+FE2E-FE2F;
}
@font-face {
  font-family: Inter;
  font-style: normal;
  font-display: swap;
  font-weight: 100 900;
  src: url("inter-cyrillic-wght-normal.woff2") format('woff2-variations');
  unicode-range: U+0301,U+0400-045F,U+0490-0491,U+04B0-04B1,U+2116;
}
@font-face {
  font-family: Inter;
  font-style: normal;
  font-display: swap;
  font-weight: 100 900;
  src: url("inter-latin-ext-wght-normal.woff2") format('woff2-variations');
  unicode-range: U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF;
}
@font-face {
  font-family: Inter;
  font-style: normal;
  font-display: swap;
  font-weight: 100 900;
  src: url("inter-latin-wght-normal.woff2") format('woff2-variations');
  unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}
* { box-sizing: border-box; }
:root {
  color-scheme: light;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --ink: #1C1A3F;
  --brand: #3D3A8C;
  --accent: #A6A2E8;
  --paper: #F3F1EC;
  --surface: #fff;
  --muted: color-mix(in srgb, var(--ink) 75%, var(--surface));
  --line: color-mix(in srgb, var(--ink) 20%, var(--surface));
  --soft: color-mix(in srgb, var(--paper) 65%, var(--surface));
  --selected: color-mix(in srgb, var(--accent) 25%, var(--surface));
  color: var(--ink);
  background: var(--paper);
  --radius: 10px;
  --section-space: 64px;
}
html { scroll-behavior: smooth; }
body { margin: 0; }
[hidden] { display: none !important; }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
button:disabled { cursor: default; opacity: .52; }
:where(button, a, input, select, textarea, summary):focus-visible { outline: 2px solid var(--brand); outline-offset: 3px; }
a { color: inherit; text-underline-offset: .18em; }
.visually-hidden { position: absolute; inline-size: 1px; block-size: 1px; padding: 0; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.icon-library { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon { width: 21px; height: 21px; flex: none; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.shell { width: min(1100px, calc(100% - 48px)); margin-inline: auto; }
.site-header { min-block-size: 68px; display: flex; align-items: center; justify-content: space-between; gap: 12px 20px; border-block-end: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; flex: none; min-block-size: 36px; }
.brand img { display: block; inline-size: 104px; block-size: auto; }
.mail-brand img { inline-size: 167px; }
.header-actions, .footer-links, .result-controls, .dialog-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; }
.quiet, .secondary, .primary { display: inline-flex; align-items: center; justify-content: center; text-align: center; gap: 6px; min-block-size: 36px; padding: 7px 10px; font-size: 14px; line-height: 1.4; border: 1px solid transparent; border-radius: 8px; background: transparent; text-decoration: none; overflow-wrap: anywhere; }
.quiet:hover, .secondary:hover:not(:disabled) { background: var(--soft); }
.secondary, .header-membership { color: var(--brand); border-color: var(--line); background: var(--surface); }
.header-actions > :is(.quiet, select) { min-block-size: 36px; }
#ui-language { min-inline-size: 84px; max-inline-size: 150px; field-sizing: content; font-size: 14px; }
.primary { background: var(--brand); color: var(--surface); border-color: var(--brand); font-size: 16px; font-weight: 620; min-block-size: 46px; }
.primary:hover:not(:disabled) { background: color-mix(in srgb, var(--brand) 68%, var(--ink)); }
.workbench, #membership { scroll-margin-block-start: 20px; }
.workbench { min-block-size: calc(100svh - 68px); }
.intro { text-align: center; padding-block: 57px 30px; }
h1, h2, h3, p { margin: 0; }
h1 { font-size: 40px; font-weight: 710; line-height: 1.18; letter-spacing: -.036em; text-wrap: balance; }
h1:lang(ar) { letter-spacing: 0; }
.intro p { margin-block-start: 12px; color: var(--muted); font-size: 18px; line-height: 1.55; }
h2 { font-size: 22px; line-height: 1.32; font-weight: 650; }
h3 { font-size: 16px; line-height: 1.45; font-weight: 650; }
.editor { border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: 0 2px 7px color-mix(in srgb, var(--ink) 5%, transparent); }
.task-tabs { display: flex; align-items: stretch; padding-inline: 12px; border-block-end: 1px solid var(--line); overflow-x: auto; scrollbar-width: thin; }
.tab { flex: 0 0 auto; min-block-size: 48px; padding: 9px 15px 7px; background: transparent; border: 0; border-block-end: 2px solid transparent; color: var(--muted); font-size: 14px; outline-offset: -4px; }
.tab:hover { background: var(--soft); }
.tab.active { color: var(--brand); border-block-end-color: var(--brand); background: var(--selected); font-weight: 650; }
.workspace { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.pane { min-inline-size: 0; min-block-size: 414px; padding: 20px 22px; }
#form { display: flex; flex-direction: column; }
.output { border-inline-start: 1px solid var(--line); scroll-margin-block-start: 14px; }
.pane-heading { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 6px 10px; min-block-size: 36px; margin-block-end: 12px; }
.pane-heading h2 { font-size: 16px; }
.office-scenarios, .mode-switch { min-inline-size: 0; border: 0; padding: 0; margin: 0; }
.scenario-options { display: flex; flex-wrap: wrap; gap: 4px; overflow-x: auto; overscroll-behavior-inline: contain; scrollbar-width: none; -ms-overflow-style: none; padding: 3px 3px 6px; margin-inline: -3px; }
.scenario-options::-webkit-scrollbar { display: none; width: 0; height: 0; }
.scenario-options button { flex: 0 0 auto; min-block-size: 34px; padding: 5px 7px; border: 1px solid var(--line); border-radius: 8px; font-size: 14px; background: var(--surface); }
.scenario-options button:hover { background: var(--soft); }
.scenario-options button[aria-pressed="true"] { border-color: var(--brand); background: var(--brand); color: var(--surface); }
.muted { color: var(--muted); font-size: 14px; line-height: 1.55; }
#office-hint { margin-block: 4px 8px; }
.options { margin-block-end: 9px; }
summary { cursor: pointer; }
.options summary { width: fit-content; padding-block: 6px; min-block-size: 32px; color: var(--muted); font-size: 14px; }
.option-fields { padding: 12px; margin-block: 4px 5px; border: 1px solid var(--line); border-radius: 8px; }
.option-selects { display: flex; flex-wrap: wrap; gap: 8px 12px; }
.option-selects > div { min-inline-size: min(140px, 100%); flex: 1; }
.option-selects select, #feedback-rating { width: 100%; }
.option-actions { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 8px; margin-block-start: 6px; }
.option-actions #clear { margin-inline-start: auto; }
.mode-switch { display: flex; flex-wrap: wrap; gap: 6px 12px; margin-block-end: 10px; }
.mode-switch legend { margin-block-end: 6px; font-size: 14px; }
#grammar-hint, #rewrite-hint { margin-block-end: 10px; }
label { display: block; margin-block-end: 6px; font-size: 14px; }
.check { display: inline-flex; gap: 7px; align-items: flex-start; font-size: 14px; line-height: 1.55; margin: 0; }
.check input { flex: none; width: 16px; height: 16px; margin: 3px 0 0; accent-color: var(--brand); }
select, textarea, input[type="email"] { min-inline-size: 0; max-inline-size: 100%; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; }
select, input[type="email"] { min-block-size: 40px; padding: 6px 9px; font-size: 16px; }
textarea { width: 100%; display: block; padding: 12px; line-height: 1.62; font-size: 16px; resize: vertical; }
textarea::placeholder { color: var(--muted); }
#prompt { flex: 1 0 auto; min-block-size: 160px; }
#incoming-wrap { margin-block-end: 8px; }
.counter { align-self: end; margin-block: 5px 8px; color: var(--muted); text-align: end; font-size: 14px; line-height: 1.35; }
#generate { width: 100%; }
#status, #form-error, #feedback-status, #feedback-form-status, #membership-status { margin-block: 0 9px; color: var(--muted); line-height: 1.55; font-size: 14px; }
#status:empty, #form-error:empty, #feedback-status:empty, #feedback-form-status:empty, #membership-status:empty { display: none; }
.error { color: #a12725 !important; }
#error-links { display: flex; gap: 8px 14px; align-items: center; flex-wrap: wrap; margin-block-end: 8px; font-size: 14px; }
.result-paper { min-block-size: 190px; overflow-wrap: anywhere; }
.result-paper.is-example { transition: opacity .16s ease, visibility 0s; }
.result-paper.is-example #subject-text, .result-paper.is-example #result { color: color-mix(in srgb, var(--ink) 63%, var(--surface)); }
.result-paper.sample-dismissed { opacity: 0; visibility: hidden; pointer-events: none; transition: opacity .16s ease, visibility 0s linear .16s; }
@media (prefers-reduced-motion: reduce) { .result-paper.is-example, .result-paper.sample-dismissed { transition: none; } }
.example-notes { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 10px; padding: 10px 12px; background: var(--soft); border: 1px solid var(--line); border-radius: 8px; margin-block-end: 15px; font-size: 14px; line-height: 1.55; }
.example-notes strong { font-weight: 650; }
.subject-line { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 4px 10px; padding-block: 0 10px; border-block-end: 1px solid var(--line); margin-block-end: 13px; }
.subject-line > div { min-inline-size: 0; flex: 1 1 170px; }
.subject-label { display: block; margin-block-end: 4px; color: var(--muted); font-size: 14px; }
#subject-text { font-size: 16px; line-height: 1.45; font-weight: 620; }
#result { font-size: 16px; line-height: 1.65; white-space: pre-wrap; overflow-wrap: anywhere; text-align: start; }
#result.placeholder { color: var(--muted); }
.adjustments { display: flex; flex-wrap: wrap; gap: 6px; margin-block-start: 14px; }
#output-check, #review-box, #quick-feedback, #feedback-status { margin-block-start: 12px; }
#review-box { padding: 11px 12px; border: 1px solid var(--line); border-radius: 8px; font-size: 14px; line-height: 1.55; overflow-wrap: anywhere; }
#review-notices { margin: 7px 0 0; padding-inline-start: 20px; }
#review-notices > li { margin-block-end: 5px; }
#source-details { margin-block-start: 10px; font-size: 14px; }
#source-details summary { width: fit-content; padding-block: 6px; }
#source-text { margin: 5px 0; padding: 10px; font: inherit; line-height: 1.6; background: var(--soft); border-radius: 8px; max-block-size: 210px; overflow: auto; white-space: pre-wrap; overflow-wrap: anywhere; }
#diff-legend { margin-block-start: 7px; }
.diff-added { background: var(--selected); text-decoration: underline; text-underline-offset: 3px; }
.diff-removed { background: #f4e8e5; text-decoration: line-through; }
#quick-feedback { display: flex; align-items: center; flex-wrap: wrap; gap: 6px; color: var(--muted); font-size: 14px; }
.icon-button { min-inline-size: 36px; padding: 6px; }
.icon-button[aria-pressed="true"] { background: var(--selected); color: var(--brand); }
.below-tool { margin-block-start: var(--section-space); }
.below-tool > h2 { margin-block-end: 17px; }
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; list-style: none; margin: 0; padding: 0; }
.steps li { border: 1px solid var(--line); border-radius: var(--radius); padding: 17px; background: var(--surface); }
.steps .icon { display: block; margin-block-end: 9px; color: var(--brand); }
.steps p, .membership p { color: var(--muted); line-height: 1.55; margin-block-start: 5px; font-size: 16px; }
.situations > h2 { margin-block-end: 8px; }
.situations-intro { color: var(--muted); line-height: 1.6; margin-block-end: 18px; }
.situation-examples { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin: 0; padding: 0; list-style: none; }
.situation-examples li { min-inline-size: 0; }
.situation-card { display: block; width: 100%; height: 100%; padding: 16px 18px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); text-align: start; transition: background-color .15s ease, border-color .15s ease; }
.situation-card:hover, .situation-card:focus-visible { background: var(--selected); border-color: var(--accent); }
.situation-title { display: block; font-size: 16px; font-weight: 650; line-height: 1.45; }
.situation-copy { display: block; color: var(--muted); margin-block-start: 6px; line-height: 1.6; overflow-wrap: anywhere; }
.faq details { border-block-end: 1px solid var(--line); }
.faq summary { padding-block: 13px; font-size: 16px; line-height: 1.5; }
.faq details p { max-inline-size: 760px; margin-block-end: 14px; color: var(--muted); font-size: 16px; line-height: 1.6; }
.mail-count { text-align: center; padding: 18px; border-block: 1px solid var(--line); font-size: 18px; font-weight: 600; }
.membership { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1fr); gap: 16px 22px; padding: 20px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.membership-fields { display: flex; flex-wrap: wrap; gap: 7px; margin-block-end: 9px; }
.membership-fields input { flex: 1 1 145px; }
#membership-status { margin-block: 8px 0; }
.site-footer { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 10px 16px; margin-block-start: var(--section-space); padding-block: 16px 26px; border-block-start: 1px solid var(--line); color: var(--muted); font-size: 14px; line-height: 1.5; }
.footer-credit { margin-block-start: 4px; color: var(--brand); }
.footer-links { gap: 2px; }
dialog { width: min(500px, calc(100% - 28px)); max-block-size: calc(100% - 28px); padding: 20px; border: 1px solid var(--line); border-radius: var(--radius); color: var(--ink); background: var(--surface); }
dialog::backdrop { background: color-mix(in srgb, var(--ink) 32%, transparent); }
#info-text { font-size: 16px; line-height: 1.65; white-space: pre-line; }
#feedback-form > p, #feedback-form select, #feedback-form textarea { margin-block: 8px 12px; }
.dialog-actions { justify-content: flex-end; }
.stats-page { padding-block: 32px; }
.stats-page h1 { margin-block-end: 8px; }
.stats-controls, .stats-controls form { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; }
.stats-controls { justify-content: space-between; margin-block: 20px; }
.stats-controls label { margin: 0; }
.stats-table { overflow: auto; margin-block: 24px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.stats-table table { width: 100%; border-collapse: collapse; font-size: 14px; white-space: nowrap; font-variant-numeric: tabular-nums; }
.stats-table caption { text-align: start; font-size: 16px; font-weight: 650; padding: 12px; }
.stats-table thead { background: var(--selected); }
.stats-table th, .stats-table td { border-block-start: 1px solid var(--line); padding: 8px 12px; text-align: end; }
.stats-table th:first-child { text-align: start; }
@media (max-width: 740px) {
  .shell { width: calc(100% - 28px); }
  .site-header { padding-block: 10px; gap: 8px; flex-wrap: nowrap; }
  .brand img { inline-size: 84px; }
  .mail-brand img { inline-size: clamp(98px, 33vw, 135px); }
  .header-actions { flex: 1; min-inline-size: 0; flex-wrap: nowrap; justify-content: flex-end; gap: 5px; }
  #feedback-header { display: none; }
  #ui-language { flex: 0 0 92px; min-inline-size: 92px; max-inline-size: 92px; }
  .header-membership { display: block; flex: 0 1 auto; min-inline-size: 0; padding-inline: 7px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
  .intro { padding-block: 35px 21px; }
  h1 { font-size: 36px; }
  h1:lang(zh) { word-break: keep-all; }
  .intro p { margin-block-start: 8px; }
  .task-tabs { padding-inline: 4px; }
  .tab { padding-inline: 10px; }
  .scenario-options { flex-wrap: nowrap; }
  .workspace, .membership, .steps, .situation-examples { grid-template-columns: minmax(0, 1fr); }
  .pane { padding: 14px 15px; min-block-size: 0; }
  .output { border-inline-start: 0; border-block-start: 1px solid var(--line); }
  .pane-heading { margin-block-end: 8px; }
  #prompt { min-block-size: 140px; }
  .steps { gap: 9px; }
  .steps li { display: grid; grid-template-columns: auto minmax(0, 1fr); column-gap: 10px; }
  .steps .icon { grid-row: span 2; margin: 0; }
}
@media (max-width: 515px) {
  .header-actions > :is(.quiet, select) { padding: 5px 6px; font-size: 13px; }
  .tab { padding-inline: 7px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }