/* =========================================================================
   Yaah — yaah.ai
   Dark "hacker / terminal" direction: black-green, white glowing text,
   card-based. One card per real, downloadable thing. No fluff, no coming-soon.
   ========================================================================= */

:root {
  --bg:      #03070a;          /* near-black, faint blue-green */
  --panel:   rgba(10, 26, 20, .55);
  --panel-2: rgba(14, 34, 26, .8);
  --line:    rgba(60, 255, 165, .16);
  --line-hi: rgba(60, 255, 165, .42);
  --fg:      #eafff5;          /* white with a green cast */
  --dim:     #8fb2a4;
  --faint:   #5d756c;
  --accent:  #2bff95;          /* terminal green */
  --accent-2:#00e08a;
  --glow:    0 0 14px rgba(43, 255, 149, .45);
  --glow-sm: 0 0 8px rgba(43, 255, 149, .35);
  --mono: "SF Mono", "JetBrains Mono", ui-monospace, "Cascadia Code", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans Arabic", Tahoma, system-ui, sans-serif;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; min-height: 100vh;
  background: var(--bg); color: var(--fg);
  font-family: var(--sans); font-size: 17px; line-height: 1.6;
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* ---- background: deep green glow + faint grid (restrained) ---- */
.bg {
  position: fixed; inset: 0; z-index: -1; pointer-events: none;
  background:
    radial-gradient(900px 600px at 50% -8%, rgba(20, 90, 60, .42), transparent 60%),
    radial-gradient(700px 500px at 88% 8%, rgba(0, 120, 80, .16), transparent 55%),
    linear-gradient(180deg, #03080b 0%, #03070a 60%, #020506 100%);
}
.bg::after {   /* hairline grid — barely there */
  content: ""; position: absolute; inset: 0; opacity: .35;
  background-image:
    linear-gradient(rgba(60, 255, 165, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(60, 255, 165, .035) 1px, transparent 1px);
  background-size: 46px 46px;
  -webkit-mask-image: radial-gradient(900px 700px at 50% 0%, #000 30%, transparent 78%);
          mask-image: radial-gradient(900px 700px at 50% 0%, #000 30%, transparent 78%);
}

/* ---- layout ---- */
main { max-width: 760px; margin: 0 auto; padding: 0 22px 70px; }
section { margin: 0 auto; }

/* ---- header ---- */
.top { max-width: 760px; margin: 0 auto; padding: 26px 22px 8px; display: flex; align-items: center; justify-content: space-between; gap: 14px; }
.wordmark {
  font-family: var(--mono); font-weight: 700; font-size: 15px; letter-spacing: 3px;
  color: var(--fg); text-decoration: none; text-shadow: var(--glow-sm); flex: 0 0 auto;
}
.wordmark span { color: var(--accent); }

/* ---- language switcher (top-right dropdown, endonyms) ---- */
.langsw { position: relative; flex: 0 0 auto; font-family: var(--mono); }
.langbtn {
  display: inline-flex; align-items: center; gap: 6px;
  font-family: var(--mono); font-size: 12.5px; letter-spacing: .3px;
  color: var(--dim); background: var(--panel); border: 1px solid var(--line);
  border-radius: 10px; padding: 7px 11px; cursor: pointer;
  transition: border-color .16s ease, color .16s ease, box-shadow .16s ease;
}
.langbtn:hover, .langbtn:focus-visible { color: var(--fg); border-color: var(--line-hi); box-shadow: var(--glow-sm); outline: none; }
.langbtn > svg { width: 15px; height: 15px; flex: 0 0 auto; }
.langbtn .chev { width: 12px; height: 12px; opacity: .75; transition: transform .16s ease; }
.langsw.open .langbtn .chev { transform: rotate(180deg); }
.langmenu {
  position: absolute; top: calc(100% + 8px); inset-inline-end: 0; z-index: 40;
  margin: 0; padding: 6px; list-style: none; min-width: 170px;
  background: var(--panel-2); border: 1px solid var(--line-hi); border-radius: 12px;
  box-shadow: 0 14px 44px rgba(0,0,0,.6), 0 0 26px rgba(43,255,149,.08);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
}
.langmenu[hidden] { display: none; }
.langmenu li {
  display: flex; align-items: center; gap: 9px; padding: 9px 11px;
  border-radius: 8px; font-size: 14px; color: var(--dim); cursor: pointer;
  transition: background .12s ease, color .12s ease;
}
.langmenu li::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: transparent; flex: 0 0 auto; }
.langmenu li:hover, .langmenu li:focus-visible { background: rgba(43,255,149,.08); color: var(--fg); outline: none; }
.langmenu li[aria-selected="true"] { color: var(--fg); }
.langmenu li[aria-selected="true"]::before { background: var(--accent); box-shadow: var(--glow-sm); }

/* ---- hero ---- */
.hero { padding: 54px 0 26px; }
.hero h1 {
  font-size: clamp(38px, 9vw, 62px); line-height: 1.04; margin: 0 0 18px;
  font-weight: 800; letter-spacing: -.02em;
  text-shadow: 0 0 22px rgba(180, 255, 220, .14);
}
.glow { color: var(--accent); text-shadow: var(--glow); }
.lede { font-size: clamp(16px, 2.4vw, 19px); color: var(--dim); margin: 0; max-width: 600px; }
.lede b { color: var(--fg); font-weight: 600; }
/* ---- hero kicker (YAAH = Your AI Agent Helper) + intro 段 ---- */
.kicker { font-family: var(--mono); font-size: clamp(11px, 2vw, 13px); letter-spacing: .22em; text-transform: uppercase; color: var(--accent); text-shadow: var(--glow-sm); font-weight: 700; margin: 0 0 14px; }
.intro { padding: 2px 0 22px; }
.introtxt { font-size: clamp(15px, 2.2vw, 17px); line-height: 1.6; color: var(--dim); margin: 0; max-width: 600px; }
.introtxt b { color: var(--fg); font-weight: 600; }

/* ---- product cards (download) ---- */
/* ---- 下载卡:扑克牌式(高窄·三张并排) ---- */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; padding: 24px 0 6px; }
.card {
  display: flex; flex-direction: column; align-items: center; text-align: center; gap: 11px;
  padding: 32px 20px 24px; border-radius: 18px; text-decoration: none; color: var(--fg);
  background: var(--panel-2); border: 1px solid var(--line); min-height: 210px;
  transition: transform .16s ease, border-color .16s ease, box-shadow .16s ease, background .16s ease;
}
.card:hover, .card:focus-visible {
  transform: translateY(-3px); border-color: var(--line-hi);
  box-shadow: 0 12px 44px rgba(0, 0, 0, .5), 0 0 30px rgba(43, 255, 149, .1); outline: none;
}
.card-dl { background: linear-gradient(180deg, rgba(20, 60, 44, .5), rgba(8, 22, 16, .72)); border-color: var(--line-hi); }
.card-dl:hover { box-shadow: 0 14px 50px rgba(0,0,0,.55), 0 0 36px rgba(43, 255, 149, .22); }
.card-ic { width: 52px; height: 52px; flex: 0 0 auto; margin-top: 2px; display: flex; align-items: center; justify-content: center; color: var(--accent); filter: drop-shadow(0 0 10px rgba(43,255,149,.4)); }
.card-ic svg { width: 100%; height: 100%; }
.card h2 { margin: 4px 0 0; font-size: 19px; font-weight: 700; letter-spacing: -.01em; }
.card-foot { margin-top: auto; display: flex; flex-direction: column; align-items: center; gap: 9px; width: 100%; }
.os { font-family: var(--mono); font-size: 11px; letter-spacing: .5px; color: var(--faint); }
.dlnow {
  font-family: var(--mono); font-weight: 700; font-size: 13.5px; letter-spacing: .3px;
  color: #04140d; background: var(--accent); padding: 10px 0; border-radius: 11px; width: 100%;
  box-shadow: var(--glow-sm);
}
.card-dl .arrow-dl { display: inline-block; transition: transform .16s ease; }
.card-dl:hover .arrow-dl { transform: translateY(2px); }
.badge {
  font-family: var(--mono); font-size: 12px; letter-spacing: .4px; color: var(--faint);
  background: rgba(120,150,135,.08); border: 1px solid var(--line); padding: 9px 0; border-radius: 11px; width: 100%;
}
.card.pending { opacity: .6; cursor: default; }
.card.pending:hover { transform: none; box-shadow: none; border-color: var(--line); }
.dlalt { text-align: center; font-size: 12.5px; color: var(--faint); margin: 16px 0 0; line-height: 1.7; }
.dlalt a { color: inherit; }
.dlalt .dlsoon { color: var(--faint); opacity: .7; cursor: default; }   /* macOS 即将推出:灰显·非链接(不误导可下载) */

/* ---- footer ---- */
.foot {
  max-width: 760px; margin: 0 auto; padding: 28px 22px 40px;
  font-size: 12.5px; color: var(--faint); font-family: var(--mono); letter-spacing: .3px;
  display: flex; flex-wrap: wrap; gap: 8px; align-items: center;
  border-top: 1px solid var(--line); margin-top: 30px;
}
.foot .sep { opacity: .5; }

/* ---- reveal on scroll ---- */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .card, .arrow { transition: none; }
}

@media (max-width: 720px) {
  .cards { grid-template-columns: 1fr; }                 /* 窄屏:三张卡竖排 */
  .card { min-height: 0; padding: 24px 20px 22px; }
}
@media (max-width: 560px) {
  .card-ic { width: 46px; height: 46px; }
  .langbtn { padding: 7px 9px; }
  .langmenu { min-width: 160px; }
}

/* ---- RTL (Arabic):逻辑属性已让菜单/卡片自动镜像;这里补可读性 ---- */
[dir="rtl"] .lede { line-height: 1.75; }                                                         /* 阿拉伯字形略增行高更易读 */
[dir="rtl"] .wordmark, [dir="rtl"] .os, [dir="rtl"] .foot { letter-spacing: 0; }
[dir="rtl"] .kicker { letter-spacing: normal; text-transform: none; }                            /* 阿拉伯字形:取消字距/大写变换,免破坏连字 */                /* 拉丁等宽字距在 RTL 上下文里归零,避免错位 */