/* SvipMail base reset & typography */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 .6em; font-weight: 700; }
h1 { font-size: clamp(1.6rem, 4vw, 2.4rem); }
h2 { font-size: clamp(1.3rem, 3vw, 1.8rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }
img, svg { max-width: 100%; display: block; }
button { font: inherit; cursor: pointer; }
code, pre, kbd { font-family: ui-monospace, SFMono-Regular, "Cascadia Code", Consolas, monospace; }
:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }