/* Copyright 2026 Know Your Friends contributors. SPDX-License-Identifier: Apache-2.0 */
:root {
  color-scheme: light;
  --paper: #faf9f6;
  --ink: #20261f;
  --muted: #7b8078;
  --green: #4b6548;
  --line: #e2e4dd;
  font-family: "Segoe UI", "Microsoft YaHei UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  scroll-behavior: smooth;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; cursor: pointer; }
a, button, summary { -webkit-tap-highlight-color: transparent; }
a:focus-visible, button:focus-visible, summary:focus-visible { outline: 2px solid var(--green); outline-offset: 5px; }
a:hover { color: var(--green); }
img { max-width: 100%; display: block; }
.shell { width: min(1120px, calc(100% - 96px)); margin-inline: auto; }
.skip-link { position: absolute; left: 16px; top: -60px; z-index: 10; padding: 12px; background: var(--paper); }
.skip-link:focus { top: 12px; }
.site-header { height: 88px; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 18px; font-weight: 650; }
.brand-symbol { width: 31px; height: 31px; display: grid; place-items: center; border: 1px solid #a8b29f; border-radius: 50%; color: var(--green); font: 20px "SimSun", serif; }
.brand-description { margin-left: 10px; color: var(--muted); font-size: 11px; font-weight: 400; }
.source-link { font-size: 12px; color: #5c6258; padding: 10px 0 10px 10px; }
.source-link span { margin-left: 6px; }
.hero { padding: 64px 0 57px; text-align: center; }
h1 { font-size: clamp(44px, 6.4vw, 78px); font-weight: 700; letter-spacing: -.055em; line-height: 1.22; margin: 0; }
.accent { color: var(--green); }
.hero-description { margin: 23px 0 29px; color: #777e71; font-size: 15px; letter-spacing: .035em; }
.download-button { min-height: 49px; display: inline-flex; align-items: center; justify-content: center; gap: 25px; padding: 14px 24px; background: var(--green); color: #fff; border-radius: 5px; font-size: 13px; transition: background .18s; }
.download-button:hover { color: #fff; background: #354b33; }
.hero-meta { display: flex; justify-content: center; gap: 10px; margin: 15px 0 0; color: var(--muted); font-size: 10px; }
.feature-switch { display: flex; justify-content: center; gap: 36px; margin-bottom: 22px; }
.feature-switch button { border: 0; border-bottom: 2px solid transparent; background: transparent; padding: 12px 2px; font-size: 15px; color: #92988e; }
.feature-switch button[aria-pressed="true"] { border-bottom-color: var(--green); color: var(--ink); }
.screen-stage { overflow: hidden; border: 1px solid #dfe5da; border-radius: 9px; background: #eef1eb; box-shadow: 0 16px 52px -36px #33482f66; }
.screen-panel { margin: 0; }
.image-button { display: block; width: 100%; aspect-ratio: 16 / 10; padding: 0; border: 0; background: transparent; cursor: zoom-in; }
.image-button img { width: 100%; height: 100%; object-fit: contain; }
.image-button:focus-visible { outline-offset: -4px; }
.screen-caption { display: flex; justify-content: space-between; gap: 16px; margin-top: 13px; font-size: 10px; color: #8a9084; }
.screen-number { font-variant-numeric: tabular-nums; }
.zoom-hint { margin-left: 25px; }
.screen-switch { display: flex; justify-content: center; gap: 6px; margin-top: 24px; padding: 2px 0 12px; overflow-x: auto; scrollbar-width: thin; }
.screen-switch button { flex: 0 0 auto; padding: 10px 13px; min-height: 40px; border: 1px solid transparent; border-radius: 4px; background: transparent; color: var(--muted); font-size: 11px; }
.screen-switch button[aria-pressed="true"] { color: var(--green); border-color: #cad4c3; background: #edf0e9; }
.screen-switch button:hover { color: var(--green); }
.practical { max-width: 760px; padding-block: 42px 53px; text-align: center; }
.privacy-line { margin: 0 0 20px; font-size: 11px; color: var(--muted); line-height: 1.8; }
.release-details summary { display: inline-flex; align-items: center; gap: 20px; cursor: pointer; font-size: 11px; color: #70786a; list-style: none; padding: 10px; }
.release-details summary::-webkit-details-marker { display: none; }
.release-details[open] summary span { transform: rotate(45deg); }
.details-body { margin-top: 14px; padding: 25px 28px; border: 1px solid var(--line); background: #fffefd; border-radius: 6px; text-align: left; color: #737b6d; font-size: 12px; line-height: 1.9; }
.details-body p { margin: 0 0 14px; }
.release-meta { color: var(--ink); font-size: 11px; }
.release-link { color: var(--green); }
.checksum { display: grid; grid-template-columns: 1fr auto; gap: 7px 12px; align-items: center; margin-block: 20px; }
.checksum>span:first-child { grid-column: 1 / -1; font-size: 10px; }
.checksum code { font-size: 10px; font-family: Consolas, monospace; overflow-wrap: anywhere; background: #f5f6f1; padding: 8px; }
.copy-checksum { background: transparent; border: 1px solid var(--line); padding: 8px 12px; font-size: 11px; }
.site-footer { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; border-top: 1px solid var(--line); padding-block: 26px 22px; color: var(--muted); font-size: 10px; }
.footer-name { font-size: 12px; color: #61695b; }
.footer-links { display: flex; justify-content: flex-end; gap: 25px; }
.site-footer>p { grid-column: 1 / -1; margin: 0; font-size: 9px; color: #9b9f95; }
.site-footer>p a { text-decoration: underline; text-underline-offset: 3px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.image-viewer { width: min(1600px, 96vw); max-width: 96vw; max-height: 94vh; padding: 0; border: 1px solid var(--line); border-radius: 7px; background: var(--paper); color: var(--ink); }
.image-viewer::backdrop { background: #182216dc; }
.image-viewer>header, .image-viewer>footer { display: flex; align-items: center; justify-content: space-between; padding: 12px 18px; gap: 18px; }
.image-viewer h2 { margin: 0; font-size: 13px; font-weight: 500; }
.image-viewer header p { margin: 4px 0 0; color: var(--muted); font-size: 10px; }
.viewer-close, .viewer-previous, .viewer-next { min-height: 40px; border: 1px solid #d5dccf; border-radius: 3px; background: transparent; padding: 7px 12px; font-size: 11px; white-space: nowrap; }
.viewer-image { overflow: auto; max-height: calc(94vh - 144px); background: #e9ede3; }
.viewer-image img { width: 100%; height: auto; }
.viewer-count { color: var(--muted); font-size: 11px; }
@media (min-width: 1450px) { .hero { padding-top: 85px; } }
@media (max-width: 900px) {
  .shell { width: calc(100% - 64px); }
  .hero { padding: 52px 0 46px; }
  .screen-switch { justify-content: flex-start; }
  .screen-switch button { padding-inline: 12px; }
}
@media (max-width: 600px) {
  .shell { width: calc(100% - 36px); }
  .site-header { height: 72px; }
  .brand { font-size: 16px; gap: 8px; }
  .brand-symbol { width: 28px; height: 28px; font-size: 18px; }
  .brand-description { margin-left: 7px; font-size: 10px; }
  .source-link { font-size: 11px; }
  .hero { padding: 46px 0 39px; }
  h1 { font-size: clamp(34px, 8.7vw, 50px); letter-spacing: -.065em; line-height: 1.3; }
  .hero-description { font-size: 12px; margin: 18px 0 23px; letter-spacing: 0; }
  .download-button { min-height: 47px; font-size: 12px; padding-inline: 21px; }
  .hero-meta { font-size: 9px; gap: 8px; margin-top: 13px; }
  .feature-switch { gap: 26px; margin-bottom: 16px; }
  .feature-switch button { font-size: 13px; padding-block: 11px; }
  .screen-stage { border-radius: 5px; }
  .screen-caption { margin-top: 10px; font-size: 9px; }
  .zoom-hint { display: none; }
  .screen-switch { margin-top: 17px; gap: 4px; }
  .screen-switch button { font-size: 10px; padding-inline: 10px; }
  .practical { padding-block: 30px 36px; }
  .privacy-line { font-size: 10px; margin-bottom: 12px; }
  .details-body { padding: 20px; font-size: 11px; }
  .site-footer { padding-block: 21px; font-size: 10px; }
  .footer-links { gap: 20px; }
  .site-footer>p { line-height: 1.9; }
  .viewer-close, .viewer-previous, .viewer-next { min-height: 44px; padding-inline: 10px; }
  .image-viewer>header, .image-viewer>footer { padding-inline: 11px; gap: 10px; }
}
@media (prefers-reduced-motion: reduce) { :root { scroll-behavior: auto; } .download-button { transition: none; } }