:root {
  color-scheme: light;
  --ink: #151d38;
  --muted: #515c76;
  --subtle: #616d87;
  --canvas: #f6f7fc;
  --paper: #fff;
  --soft: #f5f7ff;
  --line: #dce2ef;
  --blue: #2b4ad3;
  --blue-hover: #203bb8;
  --blue-wash: #e9eeff;
  --success: #08674b;
  --error: #a72632;
  --radius: 14px;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  accent-color: var(--blue);
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
::selection { background: #cfdaff; color: var(--ink); }
body { margin: 0; background: var(--canvas); color: var(--ink); font-size: .9375rem; line-height: 1.55; }
h1, h2, h3, p, figure, dl, dd { margin: 0; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: default; }
:focus-visible { outline: 2px solid var(--blue); outline-offset: 3px; }
.frame { width: min(100% - 64px, 1120px); margin-inline: auto; }
.symbols { position: absolute; width: 0; height: 0; overflow: hidden; }
svg { display: inline-block; vertical-align: middle; }
svg:has(> use) { width: 20px; height: 20px; flex: none; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.visually-hidden, input[type="file"] {
  position: absolute; width: 1px; height: 1px; margin: -1px; padding: 0;
  clip-path: inset(50%); white-space: nowrap; overflow: hidden; border: 0;
}
.topbar { background: var(--paper); border-bottom: 1px solid var(--line); }
.topbar-inner { min-height: 66px; display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.brand { display: inline-flex; align-items: center; gap: 11px; font-size: 1rem; font-weight: 750; }
.brand-icon { width: 34px; height: 34px; display: grid; place-items: center; color: white; background: var(--blue); border-radius: 10px; }
.brand-icon svg { width: 21px; height: 21px; }
.brand small { margin-left: 9px; color: var(--subtle); font-size: .65rem; font-weight: 750; letter-spacing: .13em; }
.footer svg { width: 15px; height: 15px; }

.site-nav { display: flex; align-items: center; flex-wrap: wrap; gap: 8px 18px; }
.site-nav a, .brand { color: inherit; text-decoration: none; }
.site-nav a { color: var(--muted); font-size: .8125rem; font-weight: 680; }
.site-nav a:hover, .field-link:hover { color: var(--blue); text-decoration: underline; text-underline-offset: 4px; }

.home-page { min-height: 100vh; min-height: 100svh; display: flex; flex-direction: column; }
.home-page main { flex: 1; display: flex; flex-direction: column; }
.home-page .topbar { background: transparent; border-bottom-color: transparent; }
.home-page .topbar-inner { min-height: 76px; }
.launchpad {
  flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center;
  min-width: 0; padding: 34px 0 38px; gap: 35px;
}
.launch-copy { text-align: center; }
.launch-copy h1 { color: var(--ink); font-size: 3.1rem; font-weight: 800; letter-spacing: -.035em; line-height: 1.2; }
.launch-copy p { margin: 13px auto 0; max-width: 34em; color: var(--muted); font-size: 1rem; text-wrap: balance; }

.orbit { width: 100%; min-width: 0; }
.orbit-stage {
  --card-width: 268px;
  --card-offset: 266px;
  position: relative; height: 338px; isolation: isolate; perspective: 1300px;
}
.orbit-card {
  --card-art: #254374;
  position: absolute; inset: 8px auto auto calc(50% - var(--card-width) / 2);
  display: block; width: var(--card-width); overflow: hidden;
  border: 0; border-radius: 15px; background: var(--paper);
  color: var(--ink); text-decoration: none;
  transition: transform 440ms cubic-bezier(.19,.72,.24,1), box-shadow 200ms;
}
.orbit-card[data-tool="steg"] { --card-art: #205459; }
.orbit-card[data-tool="watermark"] { --card-art: #79503c; }
.orbit-card[data-position="back"] {
  z-index: 0; opacity: 0; visibility: hidden; pointer-events: none;
  transform: translate3d(0, 24px, -210px) scale(.9);
}
.orbit-card[data-position="left"] {
  z-index: 1; transform: translate3d(calc(-1 * var(--card-offset)), 14px, -90px) rotateY(16deg);
  box-shadow: 0 8px 20px #14203b12;
}
.orbit-card[data-position="right"] {
  z-index: 1; transform: translate3d(var(--card-offset), 14px, -90px) rotateY(-16deg);
  box-shadow: 0 8px 20px #14203b12;
}
.orbit-card[data-position="front"] {
  z-index: 2; transform: translate3d(0, 0, 0);
  box-shadow: 0 14px 34px #14203b21;
}
.orbit-card:hover { box-shadow: 0 17px 38px #14203b29; }
.orbit-card:focus-visible { z-index: 3; }
.orbit-art { display: block; width: 100%; height: 158px; padding: 9px; background: var(--card-art); }
.orbit-card-copy { display: grid; gap: 7px; padding: 20px 22px 19px; }
.orbit-card[data-position="right"] .orbit-card-copy { text-align: right; }
.orbit-title { font-size: 1.25rem; font-weight: 750; line-height: 1.3; }
.orbit-description { min-height: 2.8em; color: var(--muted); font-size: .8125rem; line-height: 1.45; }
.orbit-action { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-top: 6px; color: var(--blue-hover); font-size: .8125rem; font-weight: 720; }
.orbit-action svg { width: 17px; height: 17px; }
.orbit-card:hover .orbit-action { text-decoration: underline; text-underline-offset: 3px; }

.orbit-controls, .orbit-selectors { display: flex; align-items: center; justify-content: center; gap: 5px; }
.orbit-controls { gap: 14px; margin-top: 21px; }
.orbit-selectors { padding: 4px; border-radius: 10px; background: #e8ecf5; }
.orbit-controls button {
  min-height: 36px; padding: 6px 14px; border: 0; border-radius: 7px;
  background: transparent; color: var(--muted); font-size: .8125rem; font-weight: 680; white-space: nowrap;
}
.orbit-controls button:hover { color: var(--blue-hover); background: #f5f7fd; }
.orbit-controls button[aria-pressed="true"] { color: var(--blue-hover); background: var(--paper); box-shadow: 0 2px 5px #14203b14; }
.orbit-controls .orbit-step {
  display: grid; width: 40px; height: 40px; min-height: 40px; padding: 0; place-items: center;
  border: 1px solid #cfd8ea; border-radius: 50%; color: var(--muted);
}
.orbit-step svg { width: 17px; height: 17px; }
.orbit-step[data-step="-1"] svg { transform: rotate(180deg); }
.home-page .footer { justify-content: flex-end; margin: 0; padding: 20px 0 22px; border-top: 1px solid var(--line); }
.no-script { margin-bottom: 18px; }

.field-notes { margin-top: 25px; padding: 22px 25px 25px; border-top: 1px solid var(--line); }
.field-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; margin-bottom: 18px; }
.field-heading h2 { font-size: 1.25rem; letter-spacing: -.02em; }
.field-heading p, .field-grid p { margin-top: 5px; color: var(--muted); font-size: .875rem; }
.field-link { display: inline-flex; align-items: center; gap: 6px; color: var(--blue-hover); text-decoration: none; font-size: .875rem; font-weight: 720; }
.field-link svg { width: 16px; height: 16px; }
.field-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 27px; }
.field-grid article + article { border-left: 1px solid var(--line); padding-left: 19px; }
.field-grid h3 a { color: inherit; text-underline-offset: 3px; }
.field-grid h3 a:hover { color: var(--blue); }
.tool-heading { margin: 30px 0 19px; }
.tool-heading h1 { font-size: 2rem; letter-spacing: -.025em; line-height: 1.2; }
.tool-heading p { margin-top: 8px; color: var(--muted); }
.tool-page > .site-nav { margin: 0 0 24px; }

.workspace { margin-top: 18px; overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius); background: var(--paper); }
.workspace-heading { display: flex; align-items: center; justify-content: space-between; gap: 18px; padding: 23px 26px; border-bottom: 1px solid var(--line); }
.workspace-heading h2 { font-size: 1.375rem; font-weight: 750; letter-spacing: -.025em; }
.workspace-heading p { color: var(--muted); margin-top: 4px; }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
.input-panel, .output-panel { min-width: 0; padding: 24px 26px 26px; }
.output-panel { background: #fafbff; border-left: 1px solid var(--line); }
h3, .payload-heading label, .range-group label { color: var(--ink); font-size: .9375rem; font-weight: 720; }
.panel-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.subtle { color: var(--subtle); font-size: .8125rem; text-align: end; }
.drop-zone {
  position: relative; display: flex; align-items: center; gap: 9px; min-width: 0;
  color: var(--ink); background: var(--soft); border: 1px dashed #aab8dc; border-radius: 10px;
  cursor: pointer; transition: background-color 150ms, border-color 150ms;
}
.drop-zone:hover, .drop-zone.dragging { border-color: var(--blue); background: var(--blue-wash); }
.drop-zone:has(input:focus-visible) { outline: 2px solid var(--blue); outline-offset: 3px; }
.primary-drop { flex-direction: column; justify-content: center; margin-top: 13px; min-height: 151px; padding: 18px 12px; text-align: center; }
.compact-drop { margin-top: 8px; padding: 10px; min-height: 67px; }
.drop-icon { width: 40px; height: 40px; flex: none; display: grid; place-items: center; color: var(--blue); background: #e4eaff; border-radius: 9px; }
.drop-title { color: var(--blue-hover); font-weight: 720; }
.drop-title span { color: var(--muted); margin-left: 4px; font-weight: 450; }
.drop-copy { display: flex; flex-direction: column; gap: 1px; min-width: 0; }
.drop-hint { color: var(--subtle); font-size: .8125rem; }
.primary-drop .drop-hint { margin-top: -5px; }
.selected-file { min-height: 24px; display: flex; align-items: center; gap: 8px; margin-top: 9px; color: var(--muted); font-size: .8125rem; overflow-wrap: anywhere; }
#metadata-size { margin-left: auto; flex: none; white-space: nowrap; font-variant-numeric: tabular-nums; }
.image-thumb { display: inline-flex; width: 44px; height: 35px; flex: none; overflow: hidden; border: 1px solid var(--line); border-radius: 6px; }
.image-thumb:has(img[hidden]), .decoded-stage:has(img[hidden]) { display: none; }
.image-thumb img { width: 100%; height: 100%; object-fit: cover; }
.compact-drop .image-thumb { margin-left: auto; }
.file-group + .file-group { margin-top: 13px; }

.metadata-empty, .empty-visual {
  display: flex; min-height: 121px; margin-top: 13px; padding: 13px 10px; align-items: center;
  justify-content: center; flex-direction: column; gap: 8px; text-align: center;
  border: 1px solid var(--line); border-radius: 9px; color: var(--muted); background: var(--paper); font-size: .875rem;
}
.metadata-empty svg, .empty-visual svg { width: 24px; height: 24px; color: #6476ad; }
.output-panel:has(#metadata-fields:not(:empty)) .metadata-empty,
.output-panel:has(#steg-encoded-wrap:not([hidden])) .encoded-empty,
.output-panel:has(#steg-decoded-wrap:not([hidden])) .decoded-empty { display: none; }
.metadata-list { margin-top: 11px; display: grid; grid-template-columns: minmax(85px, 1fr) minmax(0, 2fr); max-height: 280px; overflow: auto; font-size: .875rem; }
.metadata-list:empty { display: none; }
.metadata-list dt, .metadata-list dd { padding: 6px 0; border-bottom: 1px solid var(--line); overflow-wrap: anywhere; }
.metadata-list dt { padding-right: 8px; color: var(--muted); }
.metadata-list dd { color: var(--ink); font-weight: 560; font-variant-numeric: tabular-nums; }
.actions { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.button {
  display: inline-flex; justify-content: center; align-items: center; gap: 7px; min-height: 39px; padding: 7px 13px;
  border: 1px solid transparent; border-radius: 8px; font-size: .875rem; font-weight: 700; transition: background-color 150ms, border-color 150ms;
}
.button svg { width: 17px; height: 17px; }
.button.primary { color: white; background: var(--blue); }
.button.primary:hover:not(:disabled) { background: var(--blue-hover); }
.button.primary:disabled { color: #546287; background: #e5eaf7; }
.button.secondary { color: #2c469b; background: var(--paper); border-color: #d6dff6; }
.button.secondary:hover { background: var(--blue-wash); border-color: #b6c5ee; }
.button.sample { flex-shrink: 0; }
.status { margin-top: 9px; min-height: 1.2em; font-size: .8125rem; color: var(--muted); overflow-wrap: anywhere; }
.status:empty { display: none; }
.status[data-tone="error"], .status[data-tone="danger"] { color: var(--error); }
.status[data-tone="success"], .status[data-tone="ok"] { color: var(--success); }

.range-group { margin: 16px 0 12px; }
.range-group output { color: var(--blue-hover); font-weight: 700; font-variant-numeric: tabular-nums; }
input[type="range"] { width: 100%; margin: 8px 0 0; cursor: pointer; }
#steg-encoded-wrap, #steg-decoded-wrap { margin-top: 13px; }
.image-stage { display: grid; min-width: 0; min-height: 126px; place-items: center; padding: 8px; background: var(--paper); border: 1px solid var(--line); border-radius: 9px; overflow: hidden; }
.image-stage img { display: block; max-width: 100%; max-height: 330px; height: auto; object-fit: contain; }
.helper { margin-top: 12px; color: var(--muted); font-size: .8125rem; }

.mode-tabs { display: flex; gap: 5px; padding: 10px 26px; border-bottom: 1px solid var(--line); }
.mode-tabs button {
  min-width: 66px; min-height: 34px; padding: 4px 12px; border: 1px solid transparent; border-radius: 7px;
  color: var(--muted); background: transparent; font-weight: 650;
}
.mode-tabs button:hover { background: var(--soft); }
.mode-tabs button[aria-selected="true"] { border-color: #d5dffd; color: var(--blue-hover); background: var(--blue-wash); }
.payload-heading { margin: 14px 0 8px; align-items: center; }
select, textarea { border: 1px solid #bcc8e2; border-radius: 8px; background: var(--paper); color: var(--ink); }
select { padding: 4px 7px; }
textarea { display: block; width: 100%; min-height: 86px; padding: 9px 10px; resize: vertical; }
textarea::placeholder { color: var(--subtle); }
.capacity { display: flex; justify-content: space-between; gap: 8px; margin: 9px 0 13px; font-size: .8125rem; color: var(--muted); }
.capacity strong { margin-left: 3px; color: var(--ink); font-variant-numeric: tabular-nums; }
.result-name { color: var(--muted); font-size: .875rem; margin-bottom: 8px; overflow-wrap: anywhere; }
.result-name:empty { display: none; }
pre { max-height: 290px; overflow: auto; margin: 0; padding: 13px; border: 1px solid var(--line); border-radius: 9px; background: var(--paper); font: inherit; white-space: pre-wrap; overflow-wrap: anywhere; }
.footer { display: flex; justify-content: space-between; gap: 12px; margin: 20px 0 24px; font-size: .75rem; color: var(--subtle); }
.footer span:first-child { display: inline-flex; align-items: center; gap: 6px; }
.footer span[lang] { font-weight: 750; letter-spacing: .13em; }

@media (max-width: 760px) {
  .frame { width: calc(100% - 40px); }
  .workspace-heading, .input-panel, .output-panel { padding-inline: 18px; }
  .mode-tabs { padding-inline: 18px; }
}
@media (max-width: 590px) {
  .frame { width: calc(100% - 32px); }
  .topbar-inner { min-height: 58px; }
  .brand small { display: none; }
  .workspace { margin-top: 11px; }
  .tool-heading { margin: 21px 0 15px; }
  .tool-heading h1 { font-size: 1.5rem; }
  .workspace-heading { align-items: flex-start; padding: 15px; gap: 8px; }
  .workspace-heading h2 { font-size: 1.125rem; }
  .workspace-heading p { font-size: .8125rem; }
  .button.sample { padding: 5px 8px; min-height: 33px; font-size: .75rem; gap: 4px; }
  .button.sample svg { width: 14px; height: 14px; }
  .split { grid-template-columns: minmax(0, 1fr); }
  .input-panel, .output-panel { padding: 16px 15px; }
  .output-panel { border-top: 1px solid var(--line); border-left: 0; }
  .mode-tabs { padding: 8px 15px; }
  .footer span[lang] { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: 0s !important; }
}

.info-page { max-width: 850px; }
.info-page > h1 { margin-top: 27px; font-size: 2rem; line-height: 1.2; letter-spacing: -.025em; }
.info-page > p { margin-top: 8px; color: var(--muted); }
.info-content { padding: 36px 44px; margin: 28px 0; border: 1px solid var(--line); border-radius: var(--radius); background: var(--paper); }
.info-content h1 { font-size: 2rem; line-height: 1.2; letter-spacing: -.025em; }
.info-content h2 { margin-top: 28px; font-size: 1.25rem; scroll-margin-top: 15px; }
.info-content section:first-child h2 { margin-top: 0; }
.info-content section { scroll-margin-top: 15px; }
.info-content h3 { margin-top: 17px; }
.info-content p { margin-top: 8px; color: var(--muted); }
.info-content li { margin-top: 4px; color: var(--muted); }
.info-content a, .info-nav a, .topbar-inner > a { color: var(--blue-hover); text-underline-offset: 3px; }
.info-content .button.primary, .topbar-inner > .brand { color: inherit; }
.info-content .button.primary { color: #fff; }
.info-nav { display: flex; flex-wrap: wrap; gap: 8px 18px; margin-block: 14px; }
.footer .info-nav { margin-block: 0; }

@media (max-width: 980px) {
  .orbit-stage { --card-width: 250px; --card-offset: 230px; }
}
@media (max-width: 760px) {
  .home-page .topbar-inner { min-height: 66px; }
  .launchpad { gap: 28px; padding-top: 30px; }
  .launch-copy h1 { font-size: 2.5rem; }
  .launch-copy p { max-width: 26em; font-size: .9375rem; }
  .orbit-stage { --card-width: 244px; --card-offset: 190px; height: 326px; }
  .orbit-art { height: 148px; }
  .orbit-card-copy { padding: 18px; }
  .orbit-card:not([data-position="front"]) .orbit-description,
  .orbit-card:not([data-position="front"]) .orbit-action { visibility: hidden; }
  .field-notes { margin-top: 18px; padding-inline: 7px; }
  .field-grid { gap: 13px; }
  .field-grid article + article { padding-left: 12px; }
}
@media (max-width: 590px) {
  .home-page .launchpad { width: calc(100vw - 2px); margin-inline: calc((100% - 100vw + 2px) / 2); overflow: hidden; }
  .launch-copy { padding-inline: 19px; }
  .launch-copy h1 { font-size: 2.15rem; }
  .launch-copy p { max-width: 23em; font-size: .875rem; }
  .orbit-stage { --card-width: 226px; --card-offset: 169px; height: 309px; }
  .orbit-art { height: 134px; }
  .orbit-card[data-position="left"] { transform: translate3d(calc(-1 * var(--card-offset)), 16px, -145px) rotateY(20deg); }
  .orbit-card[data-position="right"] { transform: translate3d(var(--card-offset), 16px, -145px) rotateY(-20deg); }
  .orbit-card:not([data-position="front"]) .orbit-card-copy { visibility: hidden; }
  .orbit-controls { gap: 9px; margin-top: 16px; }
  .orbit-controls button { padding-inline: 11px; font-size: .75rem; }
  .orbit-controls .orbit-step { width: 36px; height: 36px; min-height: 36px; }
  .home-page .footer { justify-content: center; }
}
@media (max-width: 460px) {
  .field-grid { grid-template-columns: minmax(0, 1fr); gap: 11px; }
  .field-grid article + article { padding: 11px 0 0; border-top: 1px solid var(--line); border-left: 0; }
  .field-heading { flex-direction: column; gap: 6px; margin-bottom: 13px; }
  .footer { flex-wrap: wrap; gap: 8px 16px; }
  .info-content { padding: 24px 16px; margin-top: 16px; }
}

.watermark-toolbar { display: flex; gap: 20px; flex-wrap: wrap; padding: 14px 26px; border-bottom: 1px solid var(--line); }
.watermark-toolbar label { display: flex; align-items: center; gap: 10px; font-size: .875rem; font-weight: 650; }
.watermark-settings { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 16px; }
.watermark-settings label { display: grid; gap: 6px; font-size: .8125rem; color: var(--muted); }
.watermark-settings input { width: 100%; min-width: 0; padding: 7px 9px; border: 1px solid #bcc8e2; border-radius: 8px; color: var(--ink); background: var(--paper); }
.watermark-form-label { display: block; margin: 15px 0 7px; font-size: .875rem; font-weight: 700; }
.watermark-output { margin-top: 13px; }
.watermark-output textarea { margin-top: 12px; min-height: 150px; }
.watermark-output .image-stage:has(#bw-result[hidden]) { display: none; }
.watermark-source { margin-top: 15px; font-size: .75rem; color: var(--subtle); }
.watermark-source a { color: inherit; text-underline-offset: 3px; }
.output-panel:has(#bw-result-wrap:not([hidden])) #bw-empty { display: none; }


@media (max-width: 590px) {
  .watermark-toolbar { padding: 12px 15px; gap: 12px 18px; }
  .orbit-controls { gap: 6px; }
  .orbit-controls button { padding-inline: 8px; }
  .orbit-selectors { gap: 1px; padding: 3px; }
  .orbit-controls .orbit-step { width: 30px; height: 30px; min-height: 30px; }
}