/* 系统优化助手 官网 —— 沿用软件的黑红 + 红色闪电视觉 */
:root {
  color-scheme: dark;
  --bg: #0a0a0d;
  --panel: rgba(22, 15, 17, .9);
  --panel-2: #1c1518;
  --line: #3a2126;
  --line-2: #4d2a30;
  --text: #f0ecee;
  --muted: #a08e93;
  --accent: #ff3b3b;
  --accent-2: #c62828;
  --accent-dim: rgba(255, 59, 59, .14);
  --safe: #4cc07c;
  --caution: #e0a33e;
  --maxw: 1180px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(1200px 460px at 50% -8%, rgba(120, 16, 24, .38), transparent 65%),
    radial-gradient(1000px 700px at 88% 8%, rgba(70, 8, 14, .30), transparent 60%),
    radial-gradient(900px 600px at 6% 96%, rgba(60, 8, 14, .26), transparent 60%),
    var(--bg);
  font-family: "Microsoft YaHei UI", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

#fx {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

.topbar, main, .foot { position: relative; z-index: 1; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 .5rem; font-weight: 700; letter-spacing: .5px; }

h1 {
  font-size: clamp(2.6rem, 6vw, 4.1rem);
  background: linear-gradient(180deg, #fff 20%, #ff8a7a 75%, var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 1.1rem;
}

h2 { font-size: clamp(1.5rem, 3vw, 2.05rem); }
h3 { font-size: 1.08rem; }

p { margin: 0 0 1rem; }

a { color: #ff9a8f; text-decoration: none; }
a:hover { color: #ffc0b7; }
a:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

.fine { font-size: .82rem; color: var(--muted); line-height: 1.7; }
.center { text-align: center; }
.kicker {
  color: var(--accent);
  font-size: .82rem;
  font-weight: 700;
  letter-spacing: 3px;
  text-transform: uppercase;
  margin-bottom: .4rem;
}
.sub { color: var(--muted); max-width: 62ch; }

/* ---------- top bar ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 12px 24px;
  background: rgba(10, 7, 8, .86);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); }
.brand img { border-radius: 7px; }
.brandtext { display: flex; flex-direction: column; line-height: 1.15; }
.brandtext b { font-size: 1rem; letter-spacing: .5px; }
.brandtext i { font-style: normal; font-size: .7rem; color: var(--muted); letter-spacing: 1px; }
.navlinks { display: flex; gap: 4px; margin-left: auto; flex-wrap: wrap; }
.navlinks a {
  color: var(--muted);
  font-size: .88rem;
  padding: 6px 11px;
  border-radius: 8px;
}
.navlinks a:hover { color: var(--text); background: var(--accent-dim); }

/* 首屏不显示顶栏，下滑后才浮出（下载按钮因此在首屏不可见） */
.js .topbar { opacity: 0; transform: translateY(-100%); pointer-events: none; }
.js .topbar.show { opacity: 1; transform: none; pointer-events: auto; }
.topbar { transition: opacity .35s ease, transform .35s ease; }

/* ---------- 首屏标语 ---------- */
.splash {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 32px 24px 40px;
}
.splashbrand {
  font-size: .84rem;
  letter-spacing: 7px;
  text-transform: uppercase;
  color: #ff8a7a;
  margin: 0 0 6px;
}
.slogan {
  font-size: clamp(2.7rem, 9.5vw, 6.2rem);
  line-height: 1.08;
  margin: 14px 0 18px;
  text-shadow: 0 0 46px rgba(255, 59, 59, .35);
}
.splashsub { color: var(--muted); font-size: .96rem; margin: 0; }
.scrollhint {
  margin-top: 10vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  color: #b9a9ae;
  font-size: .84rem;
}
.scrollhint svg { width: 26px; height: 26px; color: var(--accent); animation: bob 1.9s ease-in-out infinite; }
.scrollhint:hover { color: #fff; }
@keyframes bob {
  0%, 100% { transform: translateY(-3px); opacity: .55; }
  50% { transform: translateY(4px); opacity: 1; }
}
.dlhint { font-size: .84rem; color: var(--muted); margin-top: -2px; }
.hidden { display: none !important; }

/* ---------- buttons ---------- */
.btn {
  display: inline-block;
  padding: 13px 26px;
  border-radius: 10px;
  font-weight: 700;
  font-size: .98rem;
  color: #fff;
  background: linear-gradient(180deg, var(--accent), var(--accent-2));
  border: 1px solid #ff6a5e;
  box-shadow: 0 10px 30px rgba(198, 40, 40, .35), inset 0 1px 0 rgba(255, 255, 255, .18);
  transition: transform .15s ease, box-shadow .15s ease;
}
.btn:hover { color: #fff; transform: translateY(-1px); box-shadow: 0 14px 38px rgba(255, 59, 59, .45), inset 0 1px 0 rgba(255, 255, 255, .2); }
.btn-sm { padding: 8px 16px; font-size: .86rem; }
.btn-ghost {
  background: rgba(255, 59, 59, .07);
  border: 1px solid var(--line-2);
  color: var(--text);
  box-shadow: none;
}
.btn-ghost:hover { background: var(--accent-dim); color: #fff; box-shadow: none; }
.btn-block { display: block; text-align: center; margin-top: 6px; }

/* ---------- 备用下载线路 ---------- */
.mirror { margin-top: 18px; padding-top: 16px; border-top: 1px dashed var(--line-2); }
.mtitle { margin: 0 0 10px; font-size: .78rem; color: var(--muted); text-align: center; }
.pwd { padding: 2px 9px; border: 1px solid var(--line-2); border-radius: 6px; background: rgba(255, 59, 59, .08); color: var(--accent); font-family: ui-monospace, Consolas, monospace; font-size: .95rem; letter-spacing: 2px; }
.copybtn { margin-left: 6px; padding: 2px 9px; border: 1px solid var(--line); border-radius: 6px; background: none; color: var(--muted); font: inherit; font-size: .74rem; cursor: pointer; }
.copybtn:hover { border-color: var(--line-2); color: #fff; }

/* ---------- hero ---------- */
.hero {
  display: grid;
  grid-template-columns: 1.02fr .98fr;
  gap: 48px;
  align-items: center;
  padding-top: 24px;
  padding-bottom: 64px;
}
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 20px; }
.chip {
  font-size: .78rem;
  padding: 4px 11px;
  border-radius: 999px;
  border: 1px solid var(--line-2);
  background: rgba(28, 21, 24, .8);
  color: #d9cfd2;
}
.lede { color: #cfc4c7; max-width: 46ch; font-size: 1.03rem; }
.lede b { color: var(--accent); }
.ctarow { display: flex; flex-wrap: wrap; gap: 12px; margin: 26px 0 18px; }
.metaline {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 22px;
  font-size: .84rem;
  color: var(--muted);
}
.metaline b { color: var(--text); font-variant-numeric: tabular-nums; }

/* ---------- 背景动效开关 ---------- */
.fxtoggle {
  position: fixed;
  right: 16px;
  bottom: 16px;
  z-index: 6;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 7px 13px;
  border-radius: 999px;
  border: 1px solid var(--line-2);
  background: rgba(14, 10, 12, .86);
  color: #d9cfd2;
  font-family: inherit;
  font-size: .76rem;
  cursor: pointer;
  backdrop-filter: blur(6px);
}
.fxtoggle i { font-style: normal; }
.fxtoggle:hover { border-color: var(--accent); color: #fff; }
.fxtoggle.off { color: #6f6065; }

/* ---------- app mock ---------- */
.appmock {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: rgba(12, 9, 10, .92);
  box-shadow: 0 30px 80px rgba(0, 0, 0, .6), 0 0 0 1px rgba(255, 59, 59, .06);
  overflow: hidden;
}
.mockhead {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--line);
  background: rgba(14, 10, 12, .95);
}
.mockhead img { border-radius: 6px; }
.mh-title { display: flex; flex-direction: column; line-height: 1.3; }
.mh-title b { font-size: .9rem; }
.mh-title i { font-style: normal; font-size: .68rem; color: var(--muted); }
.mh-free { margin-left: auto; font-size: .72rem; color: var(--muted); }
.mh-free em { font-style: normal; color: var(--accent); }
.mh-btns { display: flex; gap: 5px; margin-left: 12px; }
.mh-btns i { width: 9px; height: 9px; border-radius: 50%; border: 1px solid var(--line-2); }
.mh-btns i.x { background: var(--accent-2); border-color: var(--accent-2); }

.mockbody { display: flex; min-height: 330px; }
.mockrail {
  width: 58px;
  flex: 0 0 58px;
  padding: 8px 5px;
  border-right: 1px solid var(--line);
  background: rgba(10, 7, 8, .95);
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.rt {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1px;
  padding: 6px 2px;
  border-radius: 7px;
  font-size: .95rem;
  color: #8d7c81;
  border-left: 2px solid transparent;
}
.rt b { font-size: .6rem; font-weight: 400; letter-spacing: .5px; }
.rt.on { color: var(--text); background: var(--accent-dim); border-left-color: var(--accent); }

.mockmain { flex: 1; padding: 14px; display: grid; gap: 12px; }
.mcard {
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--panel);
  padding: 14px;
}
.mhero h4 { font-size: 1.5rem; margin-bottom: 4px; color: #ff8a7a; }
.mhero p { font-size: .76rem; color: var(--muted); margin-bottom: 12px; }
.mbtns { display: flex; gap: 8px; margin-bottom: 14px; }
.mbtn {
  font-size: .76rem;
  padding: 6px 14px;
  border-radius: 8px;
  border: 1px solid var(--line-2);
  color: #d9cfd2;
}
.mbtn.solid {
  background: linear-gradient(180deg, var(--accent), var(--accent-2));
  border-color: #ff6a5e;
  color: #fff;
  font-weight: 700;
}
.mstats { display: flex; gap: 20px; flex-wrap: wrap; font-size: .68rem; color: var(--muted); }
.mstats b { display: block; font-size: 1.15rem; color: var(--accent); font-variant-numeric: tabular-nums; }
.mstats i { font-style: normal; font-size: .7rem; }

.mmonhead { display: flex; align-items: center; font-size: .76rem; color: var(--muted); margin-bottom: 10px; }
.mmonhead em {
  font-style: normal;
  margin-left: auto;
  font-size: .6rem;
  letter-spacing: 1px;
  color: var(--accent);
  border: 1px solid var(--line-2);
  border-radius: 999px;
  padding: 1px 7px;
}
.mrow { display: grid; grid-template-columns: 34px 1fr 42px; align-items: center; gap: 8px; font-size: .72rem; }
.mrow label { color: var(--muted); }
.mrow b { text-align: right; color: var(--accent); font-variant-numeric: tabular-nums; }
.bar { height: 6px; border-radius: 999px; background: #2a1d20; overflow: hidden; }
.bar i {
  display: block;
  height: 100%;
  width: var(--v);
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent-2), #ff7a5c);
  transition: width .9s ease;
}
.mspark { margin: 2px 0 6px 42px; }
.mspark canvas { display: block; width: calc(100% - 42px); max-width: 260px; height: 22px; opacity: .85; }
.mnote { font-size: .66rem; color: #7d6d72; margin: 6px 0 0; }
.mockcap { font-size: .7rem; color: #7d6d72; text-align: center; margin: 0; padding: 8px; border-top: 1px solid var(--line); background: rgba(10, 7, 8, .6); }

/* ---------- sections ---------- */
main > section { padding: 56px 24px; }
main > section.wrap { padding-left: 24px; padding-right: 24px; }
#features { padding-top: 24px; }

.grid { display: grid; gap: 16px; margin-top: 28px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--panel);
  padding: 20px 20px 16px;
  transition: border-color .2s ease, transform .2s ease;
}
.card:hover { border-color: var(--line-2); transform: translateY(-2px); }
.card h3 { color: #ffb3a8; }
.card p { font-size: .92rem; color: #cabfc2; margin-bottom: .6rem; }
.card .fine { margin-bottom: 0; }

.safety { margin-top: 32px; gap: 10px 40px; }
.srow { display: grid; grid-template-columns: 46px 1fr; gap: 14px; padding: 16px 0; border-bottom: 1px solid rgba(58, 33, 38, .7); }
.srow:last-child { border-bottom: none; }
.num { font-size: .82rem; font-weight: 700; color: var(--accent); letter-spacing: 1px; padding-top: 4px; }
.srow h3 { margin-bottom: .25rem; }
.srow p { font-size: .92rem; color: #c3b7bb; margin: 0; }

.steps { list-style: none; margin: 32px 0 0; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; counter-reset: s; }
.steps li {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--panel);
  padding: 20px;
  position: relative;
}
.steps li > span {
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--accent-dim);
  border: 1px solid var(--line-2);
  color: var(--accent);
  font-weight: 700;
  font-size: .9rem;
  margin-bottom: 12px;
}
.steps h3 { font-size: 1rem; }
.steps p { font-size: .88rem; color: #c3b7bb; margin: 0; }

/* ---------- spotlight ---------- */
.spotlight { display: grid; grid-template-columns: 1.05fr .95fr; gap: 44px; align-items: center; }
.sp-text p { color: #c8bcc0; }
.ticks { list-style: none; padding: 0; margin: 18px 0 0; }
.ticks li { position: relative; padding-left: 26px; margin-bottom: 9px; font-size: .93rem; color: #cdc2c6; }
.ticks li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: .62em;
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--accent);
  box-shadow: 0 0 10px rgba(255, 59, 59, .8);
}
.ticks.small li { font-size: .88rem; margin-bottom: 6px; }

.sp-panel {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(16, 11, 13, .95);
  padding: 16px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, .5);
}
.tp-head { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: .8rem; font-weight: 700; margin-bottom: 12px; }
.tp-head b { color: var(--accent); }
.tp-head em {
  font-style: normal;
  margin-left: auto;
  font-size: .68rem;
  font-weight: 400;
  color: var(--muted);
  border: 1px solid var(--line-2);
  border-radius: 7px;
  padding: 3px 9px;
}
.tp-head em + em { margin-left: 0; }
.tp-opts { display: grid; gap: 10px; margin-top: 4px; }
.tp-opt {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2px 10px;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 13px 14px;
  background: #120e10;
}
.tp-opt span { grid-row: 1 / 4; align-self: center; width: 12px; height: 12px; border: 1px solid var(--line-2); border-radius: 50%; }
.tp-opt b { grid-column: 2; font-size: .84rem; }
.tp-opt i { grid-column: 2; font-style: normal; font-size: .74rem; color: var(--muted); line-height: 1.5; }
.tp-opt em { grid-column: 2; font-style: normal; font-size: .68rem; color: #9c8b91; letter-spacing: .3px; }
.tp-opt.on { border-color: rgba(255, 59, 59, .42); background: var(--accent-dim); }
.tp-opt.on span { border-color: var(--accent); box-shadow: inset 0 0 0 3.5px var(--accent); }
.tp-cap { font-size: .66rem; color: #7d6d72; margin: 14px 0 0; }
@media (min-width: 1001px) {
  #tiers.spotlight { grid-template-columns: 1fr 1fr; align-items: center; }
}

/* ---------- download ---------- */
.dlgrid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; margin-top: 30px; }
.dlcard {
  border: 1px solid var(--line-2);
  border-radius: 14px;
  background: var(--panel);
  padding: 26px;
}
.dlcard h3 { color: #ffb3a8; }
.dlver { font-size: .9rem; color: var(--muted); margin-bottom: 14px; }
.dlver b { color: var(--accent); font-variant-numeric: tabular-nums; }
.dlcard .ticks { margin-top: 0; }
.req { width: 100%; border-collapse: collapse; font-size: .88rem; }
.req th { text-align: left; font-weight: 400; color: var(--muted); padding: 8px 12px 8px 0; white-space: nowrap; vertical-align: top; }
.req td { padding: 8px 0; color: #d3c8cc; border-bottom: 1px solid rgba(58, 33, 38, .55); }
.req tr:last-child td { border-bottom: none; }

/* ---------- faq ---------- */
.faqlist { margin-top: 28px; }
details {
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--panel);
  margin-bottom: 10px;
  overflow: hidden;
}
summary {
  cursor: pointer;
  padding: 16px 20px;
  font-weight: 700;
  font-size: .98rem;
  list-style: none;
  position: relative;
  padding-right: 44px;
}
summary::-webkit-details-marker { display: none; }
summary::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--accent);
  font-size: 1.2rem;
}
details[open] summary::after { content: "–"; }
details p { padding: 0 20px 18px; margin: 0; font-size: .93rem; color: #c6babf; }

.notice {
  border: 1px solid var(--line-2);
  border-radius: 14px;
  background: rgba(28, 21, 24, .75);
  padding: 24px 26px;
  margin-top: 20px;
}
.notice h3 { color: var(--caution); }
.notice p { font-size: .9rem; color: #c6babf; margin: 0; }

/* ---------- footer ---------- */
.foot { border-top: 1px solid var(--line); background: rgba(8, 6, 7, .8); margin-top: 40px; padding: 40px 0 26px; }
.footgrid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 26px; }
.fbrand { display: flex; align-items: center; gap: 9px; font-weight: 700; margin-bottom: 6px; }
.fbrand img { border-radius: 6px; }
.ftitle { font-size: .84rem; font-weight: 700; margin-bottom: 4px; }
.copy { margin-top: 26px; padding-top: 18px; border-top: 1px solid rgba(58, 33, 38, .6); font-size: .8rem; color: #7d6d72; }

/* ---------- reveal ---------- */
[data-reveal] { opacity: 0; transform: translateY(14px); transition: opacity .5s ease, transform .5s ease; }
[data-reveal].in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */
@media (max-width: 1000px) {
  .hero, .spotlight, .dlgrid { grid-template-columns: 1fr; gap: 34px; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .appmock { order: 2; }
  .footgrid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 700px) {
  body { font-size: 15px; }
  .navlinks { display: none; }
  .topbar .btn { margin-left: auto; }
  main > section { padding: 44px 18px; }
  .wrap { padding: 0 18px; }
  .grid-3, .grid-2, .steps, .footgrid { grid-template-columns: 1fr; }
  .mockrail { display: none; }
  .hero { padding-top: 40px; }
  .ctarow .btn { flex: 1 1 auto; text-align: center; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .scrollhint svg { animation: none; }
  .js .topbar { transition: none; }
  [data-reveal] { opacity: 1; transform: none; transition: none; }
  .btn, .card, .bar i { transition: none; }
}