/* ==========================================================================
   SkyxrMCLauncher · 产品官网样式
   现代深色科技风 · 纯原生 CSS · 无外部依赖
   ========================================================================== */

/* ---------- 变量 ---------- */
:root {
  --bg: #0b1220;
  --bg-alt: #0d1526;
  --card: #131c2e;
  --line: rgba(56, 189, 248, .14);
  --line-strong: rgba(56, 189, 248, .38);
  --blue: #38bdf8;
  --cyan: #22d3ee;
  --orange: #fb923c;
  --text: #c8d4e6;
  --text-dim: #8fa1bb;
  --head: #f1f6ff;
  --radius: 16px;
  --radius-sm: 12px;
  --radius-lg: 20px;
  --shadow: 0 18px 40px rgba(3, 8, 20, .55);
  --shadow-soft: 0 8px 24px rgba(3, 8, 20, .38);
  --font: "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", "HarmonyOS Sans SC", system-ui, sans-serif;
  --nav-h: 66px;
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; border: 0; }

h1, h2, h3, h4 {
  color: var(--head);
  font-weight: 700;
  line-height: 1.3;
  margin: 0 0 .6em;
  letter-spacing: .2px;
}

h1 { font-size: clamp(2.1rem, 5.2vw, 3.6rem); line-height: 1.16; }
h2 { font-size: clamp(1.5rem, 3.2vw, 2.15rem); }
h3 { font-size: 1.12rem; }
p { margin: 0 0 1em; }

a { color: var(--blue); text-decoration: none; transition: color .2s ease; }
a:hover { color: var(--cyan); }

code {
  font-family: "Cascadia Mono", Consolas, "Courier New", monospace;
  font-size: .88em;
  background: rgba(56, 189, 248, .1);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: .08em .42em;
  color: #9fd8f8;
}

.container { width: min(1180px, calc(100% - 2.6rem)); margin: 0 auto; }

section[id] { scroll-margin-top: 84px; }

::selection { background: rgba(56, 189, 248, .32); color: #fff; }

/* 滚动条 */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: #0a1120; }
::-webkit-scrollbar-thumb { background: #1e3050; border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: #29456e; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  border: 1px solid transparent;
  border-radius: 12px;
  padding: .72rem 1.35rem;
  font-family: inherit;
  font-size: .95rem;
  font-weight: 600;
  line-height: 1;
  cursor: pointer;
  white-space: nowrap;
  transition: transform .18s ease, box-shadow .22s ease, background .22s ease, border-color .22s ease, color .22s ease;
}

.btn-sm { padding: .55rem 1.05rem; font-size: .88rem; border-radius: 10px; }
.btn-lg { padding: .92rem 1.7rem; font-size: 1rem; border-radius: 14px; }

.btn-primary {
  background: linear-gradient(135deg, var(--blue), var(--cyan));
  color: #052033;
  box-shadow: 0 10px 26px rgba(56, 189, 248, .3);
}
.btn-primary:hover {
  color: #041a2b;
  transform: translateY(-2px);
  box-shadow: 0 14px 34px rgba(56, 189, 248, .46);
}

.btn-ghost {
  background: rgba(56, 189, 248, .06);
  border-color: var(--line-strong);
  color: #cfe8fa;
}
.btn-ghost:hover {
  background: rgba(56, 189, 248, .14);
  border-color: var(--blue);
  color: #fff;
  transform: translateY(-2px);
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  border-bottom: 1px solid transparent;
  transition: background .28s ease, backdrop-filter .28s ease, border-color .28s ease, box-shadow .28s ease;
}

.site-header.scrolled {
  background: rgba(11, 18, 32, .76);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  border-bottom-color: var(--line);
  box-shadow: 0 10px 30px rgba(3, 8, 20, .45);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  width: min(1180px, calc(100% - 2.6rem));
}

.brand { display: inline-flex; align-items: center; gap: .6rem; color: inherit; }
.brand:hover { color: inherit; }
.logo-mark { flex: none; }

.brand-text { font-size: 1.16rem; font-weight: 800; letter-spacing: .3px; white-space: nowrap; }
.brand-sky {
  background: linear-gradient(120deg, var(--blue), var(--cyan));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.brand-mc { color: var(--head); }

.nav { display: flex; align-items: center; gap: 1.9rem; }
.nav > a {
  position: relative;
  color: var(--text);
  font-size: .95rem;
  font-weight: 500;
  padding: .3rem 0;
}
.nav > a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--blue), var(--cyan));
  transition: width .25s ease;
}
.nav > a:hover { color: var(--head); }
.nav > a:hover::after { width: 100%; }
.nav > a.nav-cta::after { display: none; }
.nav-cta { display: none; }

.header-actions { display: flex; align-items: center; gap: .7rem; }

/* 汉堡菜单 */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 0 10px;
  border: 1px solid var(--line-strong);
  border-radius: 11px;
  background: rgba(56, 189, 248, .06);
  cursor: pointer;
}
.hamburger span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: #cfe8fa;
  transition: transform .28s ease, opacity .2s ease;
}
.hamburger.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: calc(var(--nav-h) + 4.2rem) 0 4.6rem;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  inset: -30% -10% auto -10%;
  height: 780px;
  background:
    radial-gradient(48% 55% at 22% 34%, rgba(56, 189, 248, .20), transparent 68%),
    radial-gradient(40% 48% at 78% 20%, rgba(34, 211, 238, .16), transparent 70%),
    radial-gradient(34% 40% at 60% 72%, rgba(251, 146, 60, .08), transparent 72%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.02fr 1fr;
  align-items: center;
  gap: 3.2rem;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .34rem .85rem;
  margin-bottom: 1.2rem;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(56, 189, 248, .08);
  color: #a9dcfa;
  font-size: .8rem;
  font-weight: 600;
  letter-spacing: .4px;
}

.hero h1 { margin-bottom: .55rem; }
.grad {
  background: linear-gradient(120deg, var(--blue), var(--cyan) 55%, #7dd3fc);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 34em;
  font-size: 1.06rem;
  color: var(--text);
}

.hero-actions { display: flex; flex-wrap: wrap; gap: .9rem; margin: 1.7rem 0 1.1rem; }

.hero-note {
  margin: 0;
  font-size: .87rem;
  color: var(--text-dim);
}

.hero-visual {
  position: relative;
  border-radius: var(--radius-lg);
  padding: 10px;
  background: linear-gradient(160deg, rgba(56, 189, 248, .22), rgba(34, 211, 238, .06) 45%, rgba(19, 28, 46, .6));
  box-shadow: var(--shadow);
}
.hero-visual::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  pointer-events: none;
}
.hero-visual img {
  width: 100%;
  height: auto;
  border-radius: 14px;
  border: 1px solid rgba(56, 189, 248, .1);
}

/* ---------- 统计条 ---------- */
.stats {
  padding: 0 0 1rem;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  padding: 1.7rem 1.2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(19, 28, 46, .9), rgba(13, 21, 38, .82));
  box-shadow: var(--shadow-soft);
}
.stat { text-align: center; }
.stat-num {
  font-size: clamp(1.75rem, 3.4vw, 2.4rem);
  font-weight: 800;
  line-height: 1.15;
  background: linear-gradient(120deg, var(--blue), var(--cyan));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-variant-numeric: tabular-nums;
}
.stat-label { margin-top: .25rem; font-size: .9rem; color: var(--text-dim); }

/* ---------- 通用区块 ---------- */
.section { padding: 5.2rem 0; }
.section-alt {
  background:
    radial-gradient(60% 100% at 50% 0%, rgba(56, 189, 248, .06), transparent 70%),
    var(--bg-alt);
  border-top: 1px solid rgba(56, 189, 248, .08);
  border-bottom: 1px solid rgba(56, 189, 248, .08);
}

.section-head { max-width: 720px; margin: 0 auto 2.8rem; text-align: center; }
.section-head h2 { margin-bottom: .55rem; }
.section-sub { color: var(--text-dim); margin: 0; }

.eyebrow {
  display: inline-block;
  margin-bottom: .7rem;
  color: var(--cyan);
  font-size: .82rem;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
}

/* ---------- 网格与卡片 ---------- */
.grid { display: grid; gap: 1.35rem; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-soft);
  transition: transform .28s ease, border-color .28s ease, box-shadow .28s ease;
}
.card:hover {
  transform: translateY(-6px);
  border-color: var(--line-strong);
  box-shadow: var(--shadow), 0 0 0 1px rgba(56, 189, 248, .16), 0 0 34px rgba(56, 189, 248, .16);
}

.card p:last-child { margin-bottom: 0; }
.card p { color: var(--text-dim); font-size: .94rem; }

/* 功能卡 */
.feature-card { padding: 0 0 1.5rem; overflow: hidden; }
.card-media {
  border-bottom: 1px solid var(--line);
  background: #0f1729;
  overflow: hidden;
}
.card-media img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  transition: transform .5s ease;
}
.feature-card:hover .card-media img { transform: scale(1.045); }

.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  margin: 1.3rem 1.5rem .85rem;
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  background: linear-gradient(140deg, rgba(56, 189, 248, .18), rgba(34, 211, 238, .05));
  color: var(--blue);
}
.feature-icon svg { width: 22px; height: 22px; }

.feature-card h3 { margin: 0 1.5rem .45rem; }
.feature-card > p { margin: 0 1.5rem; }

/* 加载器卡 */
.loader-card { display: flex; flex-direction: column; }
.loader-head { display: flex; align-items: center; gap: .85rem; margin-bottom: .9rem; }
.loader-head h3 { margin: 0; font-size: 1.2rem; }
.loader-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  flex: none;
  border-radius: 13px;
  border: 1px solid var(--line-strong);
  background: rgba(56, 189, 248, .09);
}
.loader-badge svg { width: 24px; height: 24px; }
.badge-forge { color: var(--orange); border-color: rgba(251, 146, 60, .34); background: rgba(251, 146, 60, .1); }
.badge-neoforge { color: #f97362; border-color: rgba(249, 115, 98, .34); background: rgba(249, 115, 98, .1); }
.badge-fabric { color: #38bdf8; }
.badge-quilt { color: #22d3ee; }

.loader-tag { font-size: .78rem; color: var(--text-dim); letter-spacing: .5px; }
.loader-meta { display: flex; flex-wrap: wrap; gap: .45rem; margin-top: auto; padding-top: 1rem; }
.chip {
  display: inline-block;
  padding: .22rem .62rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(56, 189, 248, .06);
  color: #9dc4e0;
  font-size: .76rem;
  white-space: nowrap;
}

/* 账号卡 */
.account-card { display: flex; flex-direction: column; }
.account-top { display: flex; align-items: center; gap: .75rem; margin-bottom: .35rem; }
.account-top h3 { margin: 0; }
.account-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex: none;
  border-radius: 11px;
  border: 1px solid var(--line-strong);
  background: linear-gradient(140deg, rgba(56, 189, 248, .2), rgba(34, 211, 238, .06));
  color: var(--cyan);
}
.account-icon svg { width: 21px; height: 21px; }
.account-desc { font-size: .93rem !important; }

.ticks { list-style: none; margin: .3rem 0 0; padding: 0; }
.ticks li {
  position: relative;
  padding-left: 1.6rem;
  margin-bottom: .55rem;
  color: var(--text);
  font-size: .9rem;
}
.ticks li::before {
  content: "";
  position: absolute;
  left: .2rem;
  top: .62rem;
  width: 6px;
  height: 10px;
  border: solid var(--blue);
  border-width: 0 2px 2px 0;
  transform: rotate(43deg);
}

/* ---------- 整合包区 ---------- */
.modpack-inner {
  display: grid;
  grid-template-columns: 1.06fr .94fr;
  align-items: center;
  gap: 3rem;
}
.modpack-copy .section-sub { margin-bottom: 1.6rem; }

.feature-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 1rem; }
.feature-list li {
  display: flex;
  gap: .95rem;
  padding: 1rem 1.1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: rgba(19, 28, 46, .72);
  transition: border-color .24s ease, transform .24s ease, background .24s ease;
}
.feature-list li:hover { border-color: var(--line-strong); background: rgba(23, 34, 56, .9); transform: translateX(4px); }
.fl-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  flex: none;
  border-radius: 10px;
  background: rgba(56, 189, 248, .12);
  border: 1px solid var(--line);
  color: var(--blue);
}
.fl-icon svg { width: 19px; height: 19px; }
.feature-list strong { display: block; color: var(--head); font-size: .97rem; }
.feature-list span { display: block; color: var(--text-dim); font-size: .88rem; line-height: 1.65; }

.modpack-visual {
  border-radius: var(--radius-lg);
  padding: 9px;
  background: linear-gradient(160deg, rgba(56, 189, 248, .18), rgba(19, 28, 46, .5));
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}
.modpack-visual img { border-radius: 13px; width: 100%; }

/* ---------- 下载区 ---------- */
.download-card {
  position: relative;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.download-bg { position: absolute; inset: 0; }
.download-bg img { width: 100%; height: 100%; object-fit: cover; opacity: .30; }
.download-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(120deg, rgba(11, 18, 32, .96) 12%, rgba(11, 18, 32, .8) 55%, rgba(13, 24, 42, .72)),
    radial-gradient(60% 90% at 88% 10%, rgba(56, 189, 248, .16), transparent 65%);
}
.download-body {
  position: relative;
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 2.4rem;
  padding: 2.6rem;
}
.download-main h2 { margin-bottom: .5rem; }
.download-sub { color: var(--text-dim); margin-bottom: 1.5rem; }

.dl-meta { display: grid; gap: .7rem; margin-bottom: 1.7rem; }
.dl-meta-item {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
  align-items: baseline;
  padding: .6rem .9rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: rgba(19, 28, 46, .62);
}
.dl-k { min-width: 76px; color: var(--text-dim); font-size: .84rem; }
.dl-v { color: var(--head); font-size: .92rem; font-weight: 600; }

.download-actions { display: flex; flex-wrap: wrap; gap: .85rem; }

.changelog {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(19, 28, 46, .78);
  padding: 1.4rem 1.5rem;
}
.changelog h3 { font-size: 1rem; color: var(--cyan); }
.changelog-list { list-style: none; margin: 0; padding: 0; }
.changelog-list li {
  position: relative;
  display: flex;
  gap: .7rem;
  padding-bottom: 1rem;
  color: var(--text-dim);
  font-size: .9rem;
  line-height: 1.7;
}
.changelog-list li:last-child { padding-bottom: 0; }
.changelog-list strong { color: var(--head); font-weight: 600; margin-right: .3rem; }
.ver-dot {
  position: relative;
  flex: none;
  width: 9px;
  height: 9px;
  margin-top: .62rem;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 0 4px rgba(56, 189, 248, .14);
}
.changelog-list li:not(:last-child) .ver-dot::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 14px;
  width: 1px;
  height: calc(100% + 12px);
  transform: translateX(-50%);
  background: linear-gradient(180deg, rgba(56, 189, 248, .4), transparent);
}

/* ---------- FAQ ---------- */
.faq-list { max-width: 880px; margin: 0 auto; display: grid; gap: .8rem; }

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card);
  overflow: hidden;
  transition: border-color .24s ease, box-shadow .24s ease;
}
.faq-item.open {
  border-color: var(--line-strong);
  box-shadow: 0 0 0 1px rgba(56, 189, 248, .12), 0 10px 28px rgba(3, 8, 20, .45);
}

.faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  padding: 1.15rem 1.35rem;
  border: 0;
  background: none;
  color: var(--head);
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: color .2s ease;
}
.faq-q:hover { color: var(--blue); }

.faq-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  flex: none;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--blue);
  transition: transform .3s ease, background .25s ease, border-color .25s ease;
}
.faq-icon svg { width: 15px; height: 15px; }
.faq-item.open .faq-icon {
  transform: rotate(135deg);
  background: rgba(56, 189, 248, .14);
  border-color: var(--line-strong);
}

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height .34s cubic-bezier(.4, 0, .2, 1);
}
.faq-a-inner { padding: 0 1.35rem 1.25rem; }
.faq-a-inner p { margin: 0; color: var(--text-dim); font-size: .94rem; }

/* ---------- 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, #0a1120, #080e1a);
  padding-top: 3.4rem;
}
.footer-inner {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 2.4rem;
  padding-bottom: 2.6rem;
}
.footer-brand p { margin: 1rem 0 0; color: var(--text-dim); font-size: .9rem; max-width: 34em; }
.footer-col h4 { font-size: .95rem; margin-bottom: .9rem; color: var(--head); }
.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin-bottom: .55rem; }
.footer-col a { color: var(--text-dim); font-size: .9rem; }
.footer-col a:hover { color: var(--blue); }

.footer-bottom {
  border-top: 1px solid rgba(56, 189, 248, .1);
  padding: 1.2rem 0 1.6rem;
}
.footer-bottom p { margin: 0; color: #7c8da6; font-size: .84rem; text-align: center; }

/* ---------- 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 90;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border: 1px solid var(--line-strong);
  border-radius: 13px;
  background: rgba(19, 28, 46, .9);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  color: var(--blue);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity .28s ease, transform .28s ease, visibility .28s ease, box-shadow .24s ease, background .24s ease;
}
.to-top svg { width: 20px; height: 20px; }
.to-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }
.to-top:hover {
  background: rgba(56, 189, 248, .16);
  box-shadow: 0 0 22px rgba(56, 189, 248, .3);
}

/* ---------- 滚动进入动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .7s ease, transform .7s cubic-bezier(.22, .61, .36, 1);
  will-change: opacity, transform;
}
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ---------- 响应式：平板 ---------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .hero-inner { gap: 2.2rem; }
  .modpack-inner { gap: 2rem; }
  .download-body { grid-template-columns: 1fr; gap: 2rem; padding: 2.2rem; }
  .footer-inner { grid-template-columns: 1.4fr 1fr 1fr; row-gap: 2rem; }
}

@media (max-width: 900px) {
  .header-download { display: none; }
  .hamburger { display: flex; }

  .nav {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: .6rem 1.3rem 1.2rem;
    background: rgba(11, 18, 32, .97);
    -webkit-backdrop-filter: blur(16px);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 18px 40px rgba(3, 8, 20, .6);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-12px);
    transition: opacity .26s ease, transform .26s ease, visibility .26s ease;
  }
  .nav.open { opacity: 1; visibility: visible; transform: translateY(0); }

  .nav > a { padding: .85rem .2rem; border-bottom: 1px solid rgba(56, 189, 248, .09); }
  .nav > a::after { display: none; }
  .nav-cta { display: inline-flex; margin-top: 1rem; border: 0; justify-content: center; }

  .hero { padding-top: calc(var(--nav-h) + 2.8rem); text-align: left; }
  .hero-inner { grid-template-columns: 1fr; }
  .hero-visual { margin-top: .5rem; }

  .modpack-inner { grid-template-columns: 1fr; }
  .modpack-visual { order: -1; }

  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

/* ---------- 响应式：手机 ---------- */
@media (max-width: 640px) {
  body { font-size: 15.5px; }
  .container { width: calc(100% - 2rem); }
  .header-inner { width: calc(100% - 2rem); }
  .brand-text { font-size: 1rem; }
  .logo-mark { width: 32px; height: 32px; }

  .section { padding: 3.6rem 0; }
  .section-head { margin-bottom: 2rem; }

  .hero { padding-bottom: 3rem; }
  .hero-actions { gap: .7rem; }
  .hero-actions .btn { width: 100%; }

  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 1.4rem .8rem; padding: 1.4rem 1rem; }

  .grid-3, .grid-4 { grid-template-columns: 1fr; }

  .feature-icon { margin: 1.1rem 1.2rem .7rem; }
  .feature-card h3 { margin-left: 1.2rem; margin-right: 1.2rem; }
  .feature-card > p { margin-left: 1.2rem; margin-right: 1.2rem; }

  .modpack-copy h2 { font-size: 1.45rem; }

  .download-body { padding: 1.5rem; }
  .download-actions .btn { width: 100%; }
  .dl-meta-item { flex-direction: column; gap: .15rem; }

  .faq-q { padding: 1rem 1.05rem; font-size: .95rem; }
  .faq-a-inner { padding: 0 1.05rem 1.05rem; }

  .footer-inner { grid-template-columns: 1fr 1fr; gap: 1.8rem; }
  .footer-brand { grid-column: 1 / -1; }

  .to-top { right: 1rem; bottom: 1rem; width: 42px; height: 42px; }
}

/* ---------- 无障碍 / 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}