/* ============================================================
   2026-07-20 深色模式（prefers-color-scheme: dark）
   雪夜书信在深色系统里变成真正的雪夜：
   墨色纸底、朱砂更亮、梅花带微光。
   ============================================================
   本文件不自带媒体查询，由 site.js 的主题管理器通过
   <link id="dark-css"> 的 media 属性控制启用时机：
   跟随系统 → '(prefers-color-scheme: dark)'
   强制深色 → 'all'；强制浅色 → 'not all'。 */
html{color-scheme:dark}
:root{
  --bg:#101713;
  --paper:#16211b;
  --paper-2:#1b2620;
  --ink:#edf2ed;
  --ink-2:#c9d4cc;
  --muted:#8fa099;
  --line:#2a3830;
  --line-2:#3a4a41;
  --red:#b04a5c;
  --green:#3a967f;
  --dark:#0c110e;
  --shadow:0 20px 60px rgba(0,0,0,.4);
}
.site{background:linear-gradient(180deg,#151e19 0%,#101713 60%,#0c110e 100%)}
/* 导航 */
.nav{background:rgba(16,23,19,.86);border-bottom-color:rgba(255,255,255,.10)}
.brand .mark-logo{background:#f5f6f2;padding:3px}
.nav-links .nav-cta{color:#101713}
.nav-links .nav-cta:hover,.nav-links .nav-cta.active{color:#fff}
.product-dropdown{background:rgba(24,33,28,.97);border-color:rgba(255,255,255,.12);box-shadow:0 18px 48px rgba(0,0,0,.5)}
.product-dropdown a{color:var(--ink)}
/* Hero（产品页/公司页） */
.hero-letter,.co-hero{background:linear-gradient(112deg,#18231e 0%,#141d18 55%,#1d1a18 100%)}
.hero-letter::before,.co-hero::before{
  background:
    linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px),
    linear-gradient(0deg,rgba(255,255,255,.035) 1px,transparent 1px);
  background-size:72px 72px;
}
.co-mark{background:#f5f6f2;padding:6px}
.scroll-hint{color:rgba(255,255,255,.35)}
/* 纸纹 */
.page-grain{mix-blend-mode:soft-light;opacity:.06}
/* 按钮 */
.button{border-color:var(--ink)}
.button.dark{color:#101713;background:var(--ink)}
.button.dark:hover{color:#fff;background:var(--red);border-color:var(--red)}
.button.light{background:rgba(255,255,255,.06)}
/* 白色分区转墨 */
.evidence,.pricing,.siwo-statement,.section.white{background:#141c17}
.evidence,.trust,.pricing,.siwo-access,.colophon,.page-hero,.letter-page section{border-top-color:rgba(255,255,255,.10)}
.evidence-copy>p,.memory-quiet{color:var(--muted)}
.evidence-note{border-top-color:rgba(255,255,255,.14)}
/* 承诺与定价 */
.trust-grid{border-color:rgba(255,255,255,.12);background:rgba(255,255,255,.12)}
.price-card{border-color:rgba(255,255,255,.14);box-shadow:none}
.price-card:hover{box-shadow:0 22px 54px rgba(0,0,0,.45)}
.price-card ul{border-top-color:rgba(255,255,255,.12)}
.price-card.featured{
  color:#101713;
  border-color:#eef2ee;
  background:linear-gradient(160deg,rgba(159,47,63,.22),transparent 46%),#eef2ee;
  box-shadow:0 34px 76px rgba(0,0,0,.5);
}
.price-card.featured .plan{color:#4a5a52}
.price-card.featured .amount{color:#101713}
.price-card.featured .amount small{color:#6a7770}
.price-card.featured ul{border-top-color:rgba(15,20,18,.14)}
.price-card.featured li{color:#2c3732}
/* 获取 */
.access-list,.access-row{border-color:rgba(255,255,255,.16)}
.access-row.available:hover{background:#1a241f}
/* 卡片与杂项 */
.card,.card.tall{background:#1a241f}
.company-page .page-hero h1{color:var(--ink)}
.company-contact-item{border-bottom-color:rgba(255,255,255,.12)}
.contact-page .company-contact-item:nth-child(odd){border-right-color:rgba(255,255,255,.12)}
.contact-blank-line{background:rgba(255,255,255,.16)}
.command,.visual-panel{
  background:
    linear-gradient(90deg,rgba(255,255,255,.05) 1px,transparent 1px),
    linear-gradient(0deg,rgba(255,255,255,.04) 1px,transparent 1px),
    linear-gradient(145deg,#1a241f,#141d18);
  background-size:42px 42px,42px 42px,100% 100%;
  border-color:rgba(255,255,255,.12);
}
.product-panel{background:#1a241f;border-color:rgba(255,255,255,.12)}
.product-panel.featured{background:linear-gradient(160deg,rgba(159,47,63,.24),transparent 44%),#22302a;color:#fff}
.footer{border-top-color:rgba(255,255,255,.10)}
/* 结尾深绿不变（本身就是夜） */
/* 夜梅：picture 元素已切换为透明底夜梅图，正常混合即可 */
.hero-plum img{
  mix-blend-mode:normal;
  opacity:.94;
  filter:none;
  -webkit-mask-image:none;
  mask-image:none;
}

/* 主题切换按钮：深色适配 */
.theme-toggle{border-color:var(--line-2);color:var(--ink-2)}
.theme-toggle:hover{color:var(--ink);background:rgba(255,255,255,.06)}