/* digital-watermarking · 基础主题、表单与内容元素 */
:root {
  --bg: #f7f9fc;
  --bg-soft: #eef3fb;
  --surface: #ffffff;
  --surface-strong: #e8effc;
  --border: #dbe3f0;
  --border-hi: #b8c7dc;
  --text: #081b35;
  --text-soft: #4f617a;
  --text-dim: #5f7088;
  --accent: #2e63ff;
  --on-accent: #ffffff;
  --accent-2: #15c8d5;
  --accent-bg: #eaf0ff;
  --ok: #17835b;
  --warn: #a46612;
  --danger: #c43e32;
  --danger-bg: #fff0ed;
  --signal-bg: #06101f;
  --signal-surface: #0d1a31;
  --signal-text: #edf5ff;
  --signal-soft: #91a8c9;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --radius: 14px;
  --radius-lg: 24px;
  --shadow: 0 18px 48px -30px rgba(8, 27, 53, .38);
  --shadow-hi: 0 28px 70px -34px rgba(16, 54, 112, .46);
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #08101d;
    --bg-soft: #0d1829;
    --surface: #101d30;
    --surface-strong: #152742;
    --border: #253854;
    --border-hi: #3d5578;
    --text: #edf4ff;
    --text-soft: #a6b6cd;
    --text-dim: #8293ac;
    --accent: #6b8dff;
    --on-accent: #07152a;
    --accent-2: #3dd5df;
    --accent-bg: #14264a;
    --ok: #55c996;
    --warn: #e2ae5e;
    --danger: #ff8176;
    --danger-bg: #321d22;
    --shadow: 0 20px 52px -30px rgba(0, 0, 0, .9);
    --shadow-hi: 0 30px 76px -34px rgba(0, 0, 0, .95);
  }
}

*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body::selection { background: color-mix(in srgb, var(--accent) 28%, transparent); }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }

img, svg, canvas { max-width: 100%; }

strong { font-weight: 650; }

h1, h2, h3 { color: var(--text); text-wrap: balance; }
h2 { margin: 56px 0 16px; font-size: clamp(22px, 2.4vw, 30px); line-height: 1.28; letter-spacing: -.035em; }
h3 { margin: 26px 0 9px; font-size: 16px; line-height: 1.4; letter-spacing: -.015em; }

p { text-wrap: pretty; }
hr { border: 0; border-top: 1px solid var(--border); margin: 36px 0; }

code, kbd, samp, pre { font-family: var(--mono); font-size: .88em; }
code:not(pre code) {
  padding: .12em .4em;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg-soft);
}

label { display: block; margin-bottom: 7px; color: var(--text-soft); font-size: 13px; font-weight: 550; }

input[type=text], input[type=password], textarea, select {
  width: 100%;
  padding: 11px 13px;
  border: 1px solid var(--border);
  border-radius: 10px;
  outline: none;
  background: var(--bg);
  color: var(--text);
  font: inherit;
  font-size: 14px;
  transition: border-color .16s, box-shadow .16s, background .16s;
}

input[type=text]:focus, input[type=password]:focus, textarea:focus, select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 17%, transparent);
  background: var(--surface);
}

textarea { min-height: 126px; resize: vertical; line-height: 1.7; }
textarea.mono { font-family: var(--mono); font-size: 13px; }
input[type=range] { width: 100%; accent-color: var(--accent); }

input[type=file] {
  width: 100%;
  padding: 16px;
  border: 1px dashed var(--border-hi);
  border-radius: 12px;
  background: var(--bg-soft);
  color: var(--text-soft);
  font-size: 13px;
  cursor: pointer;
}

input[type=file]::file-selector-button {
  margin-right: 12px;
  padding: 7px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  color: var(--text);
  font: inherit;
  font-size: 13px;
  cursor: pointer;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 40px;
  padding: 9px 15px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text);
  font: inherit;
  font-size: 13.5px;
  font-weight: 560;
  cursor: pointer;
  transition: transform .16s, border-color .16s, background .16s, box-shadow .16s;
}

.btn:hover { border-color: var(--border-hi); text-decoration: none; transform: translateY(-1px); box-shadow: var(--shadow); }
.btn:active { transform: translateY(0); }
.btn:focus-visible { outline: 3px solid color-mix(in srgb, var(--accent) 34%, transparent); outline-offset: 2px; }
.btn:disabled { opacity: .45; cursor: not-allowed; transform: none; box-shadow: none; }
.btn--primary { border-color: var(--accent); background: var(--accent); color: var(--on-accent); }
.btn--primary:hover { border-color: color-mix(in srgb, var(--accent) 82%, #fff); background: color-mix(in srgb, var(--accent) 88%, #fff); }

.field + .field { margin-top: 16px; }
.btn-row { display: flex; flex-wrap: wrap; gap: 9px; align-items: center; }

.badge {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  padding: 2px 9px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-soft);
  color: var(--text-soft);
  font-size: 11px;
  font-weight: 620;
  line-height: 1.4;
  white-space: nowrap;
}
.badge--accent { border-color: color-mix(in srgb, var(--accent) 50%, var(--border)); background: var(--accent-bg); color: var(--accent); }
.badge--ok { border-color: color-mix(in srgb, var(--ok) 55%, var(--border)); color: var(--ok); }
.badge--warn { border-color: color-mix(in srgb, var(--warn) 55%, var(--border)); color: var(--warn); }
.badge--danger { border-color: color-mix(in srgb, var(--danger) 55%, var(--border)); background: var(--danger-bg); color: var(--danger); }

.note {
  padding: 15px 18px;
  border: 1px solid color-mix(in srgb, var(--accent) 28%, var(--border));
  border-left: 3px solid var(--accent);
  border-radius: 0 12px 12px 0;
  background: color-mix(in srgb, var(--accent-bg) 72%, var(--surface));
  color: var(--text-soft);
  font-size: 13.5px;
}
.note strong { color: var(--text); }
.muted { color: var(--text-soft); font-size: 13px; }
.cp { color: var(--text-soft); font-family: var(--mono); }

.table-scroll { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; font-size: 13.5px; }
th, td { padding: 11px 13px; border-bottom: 1px solid var(--border); text-align: left; vertical-align: top; }
th { color: var(--text-soft); font-size: 12px; font-weight: 620; letter-spacing: .02em; white-space: nowrap; }
tbody tr:last-child td { border-bottom: 0; }
tbody tr:hover { background: color-mix(in srgb, var(--accent-bg) 38%, transparent); }

.canvas-box {
  padding: 12px;
  overflow: auto;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--bg-soft);
}
.canvas-box canvas, .canvas-box img { display: block; max-width: 100%; height: auto; }
.canvas-box:empty { display: none; }
.canvas-box:has(canvas:not([width])) { display: none; }
.figure:has(canvas:not([width])), .figure:has(.canvas-box:empty) { display: none; }
.figure > p { margin-top: 0; }

#toast {
  position: fixed;
  left: 50%;
  bottom: 32px;
  z-index: 100;
  padding: 9px 16px;
  border: 1px solid color-mix(in srgb, var(--signal-text) 18%, transparent);
  border-radius: 999px;
  background: var(--signal-bg);
  color: var(--signal-text);
  font-size: 13px;
  opacity: 0;
  pointer-events: none;
  transform: translate(-50%, 12px);
  transition: opacity .2s, transform .2s;
}
#toast.show { opacity: 1; transform: translate(-50%, 0); }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}