/* =========================================================
   班级积分统计系统 · 宣传站
   性能约定：滚动区域不使用 backdrop-filter / mask，
   所有动效只跑 transform 与 opacity，避免滚动掉帧。
   ========================================================= */

:root{
  --ink:#0A1424;
  --ink-2:#10243C;
  --ink-3:#183452;
  --blue:#2563EB;
  --blue-2:#1D4FD7;
  --blue-soft:#7FB0FF;
  --bg:#F3F6FB;
  --surface:#FFFFFF;
  --border:#E3E9F1;
  --text:#1B2430;
  --muted:#5A6475;
  --green:#0E9F6E;
  --red:#D92D20;
  --radius:16px;
  --shadow-sm:0 1px 2px rgba(16,36,60,.06), 0 4px 12px rgba(16,36,60,.05);
  --shadow-md:0 18px 40px -20px rgba(16,36,60,.26), 0 2px 8px rgba(16,36,60,.05);
  --wrap:1140px;
  --ease:cubic-bezier(.2,.7,.2,1);
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei","PingFang SC","Hiragino Sans GB",sans-serif;
  color:var(--text);background:var(--bg);line-height:1.75;
  -webkit-font-smoothing:antialiased;overflow-x:hidden;
}
img{max-width:100%;display:block;height:auto}
a{color:inherit;text-decoration:none}
h1,h2,h3{margin:0;line-height:1.25;letter-spacing:-.02em;font-weight:800}
p{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}

.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding:0 24px}
.wrap-narrow{max-width:840px}

/* ---------- 滚动进度条 ---------- */
.progress{
  position:fixed;left:0;top:0;height:3px;width:100%;z-index:90;
  background:linear-gradient(90deg,#7FB0FF,#2563EB);
  transform:scaleX(var(--p,0));transform-origin:0 50%;
  pointer-events:none;
}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  height:44px;padding:0 18px;border-radius:10px;border:1px solid transparent;
  font-size:14.5px;font-weight:700;cursor:pointer;white-space:nowrap;
  transition:transform .22s var(--ease), box-shadow .22s var(--ease), background .2s, border-color .2s, color .2s;
}
.btn svg{width:17px;height:17px}
.btn-primary{
  color:#fff;background:linear-gradient(180deg,#3B76F6,#2563EB 62%,#1D4FD7);
  box-shadow:0 10px 24px -14px rgba(37,99,235,.9), inset 0 1px 0 rgba(255,255,255,.26);
}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 16px 30px -16px rgba(37,99,235,1)}
.btn-primary:active{transform:translateY(0)}
.btn-ghost{color:#DCE8FA;background:rgba(255,255,255,.07);border-color:rgba(255,255,255,.2)}
.btn-ghost:hover{background:rgba(255,255,255,.13);border-color:rgba(255,255,255,.34);transform:translateY(-2px)}
.btn-line{color:var(--text);background:transparent;border-color:var(--border)}
.btn-line:hover{border-color:#B9C7DC;background:#fff}
.btn-lg{height:52px;padding:0 24px;font-size:15.5px;border-radius:12px}
.btn-sm{height:36px;padding:0 14px;font-size:13px;border-radius:9px}
.btn-block{width:100%}

/* ---------- 导航 ---------- */
.nav{
  position:fixed;inset:0 0 auto 0;z-index:70;
  transition:background .28s, box-shadow .28s, border-color .28s;
  border-bottom:1px solid transparent;
}
.nav.scrolled{
  background:rgba(9,18,32,.95);
  border-bottom-color:rgba(255,255,255,.08);
  box-shadow:0 10px 30px -22px rgba(0,0,0,.9);
}
.nav-inner{display:flex;align-items:center;gap:22px;height:68px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;font-weight:800;font-size:15px}
.brand-mark{
  width:30px;height:30px;border-radius:8px;display:grid;place-items:center;flex:0 0 auto;
  background:linear-gradient(160deg,#3B76F6,#1D4FD7);color:#fff;font-size:15px;font-weight:800;
  box-shadow:0 6px 14px -6px rgba(37,99,235,.9);
}
.nav-links{display:flex;gap:22px;margin-left:auto}
.nav-links a{color:rgba(255,255,255,.72);font-size:13.6px;font-weight:600;position:relative;padding:6px 0;transition:color .18s}
.nav-links a::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:2px;border-radius:2px;
  background:linear-gradient(90deg,#7FB0FF,#2563EB);transform:scaleX(0);transform-origin:left;
  transition:transform .26s var(--ease);
}
.nav-links a:hover{color:#fff}
.nav-links a:hover::after{transform:scaleX(1)}
.nav-toggle{display:none;margin-left:auto;width:42px;height:42px;border:0;background:transparent;cursor:pointer;padding:10px}
.nav-toggle span{display:block;height:2px;border-radius:2px;background:#fff;margin:5px 0;transition:transform .26s var(--ease), opacity .2s}

/* ---------- HERO ---------- */
.hero{
  position:relative;overflow:hidden;color:#fff;
  background:radial-gradient(1100px 560px at 80% -10%,#183452 0%,transparent 60%),
             linear-gradient(180deg,#0A1424 0%,#0C1A2E 64%,#0A1526 100%);
  padding:130px 0 84px;
}
/* 纯静态光晕：不再参与动画，避免每帧重算模糊 */
.hero-glow{position:absolute;border-radius:50%;filter:blur(70px);pointer-events:none;opacity:.85}
.g1{width:520px;height:520px;right:-130px;top:-170px;background:rgba(37,99,235,.42)}
.g2{width:400px;height:400px;left:-150px;bottom:-170px;background:rgba(14,159,110,.2)}
.hero-grid{
  position:absolute;inset:0;pointer-events:none;opacity:.4;
  background-image:linear-gradient(rgba(127,176,255,.09) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(127,176,255,.09) 1px,transparent 1px);
  background-size:64px 64px;
}

.hero-inner{position:relative;display:grid;grid-template-columns:minmax(0,1.03fr) minmax(0,1fr);gap:56px;align-items:center}
.pill{
  display:inline-block;padding:7px 14px;border-radius:999px;font-size:12.5px;font-weight:700;letter-spacing:.03em;
  color:#BBD3F7;background:rgba(127,176,255,.12);border:1px solid rgba(127,176,255,.28);
}
.hero h1{font-size:clamp(34px,4.5vw,56px);margin:20px 0 18px;letter-spacing:-.03em}
.hero h1 em{
  font-style:normal;
  background:linear-gradient(100deg,#7FB0FF 0%,#BBD3F7 44%,#FFFFFF 80%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.lead{color:#B7C7DD;font-size:clamp(14.5px,1.25vw,16.5px);max-width:37em}
.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:28px}
.hero-meta{display:flex;flex-wrap:wrap;gap:16px;margin-top:24px;color:#8296B0;font-size:12.8px}
.hero-meta li{position:relative;padding-left:13px}
.hero-meta li::before{content:"";position:absolute;left:0;top:50%;width:5px;height:5px;border-radius:50%;background:#3B76F6;transform:translateY(-50%)}

/* 作者条 */
.hero-author{
  display:inline-flex;align-items:center;gap:12px;margin-top:26px;
  padding:9px 16px 9px 10px;border-radius:999px;
  background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.14);
  transition:background .22s, border-color .22s, transform .22s var(--ease);
}
.hero-author:hover{background:rgba(255,255,255,.11);border-color:rgba(127,176,255,.45);transform:translateY(-2px)}
.avatar{
  width:34px;height:34px;border-radius:50%;flex:0 0 auto;display:grid;place-items:center;
  background:linear-gradient(160deg,#3B76F6,#1D4FD7);color:#fff;font-size:14px;font-weight:800;
}
.ha-text{display:flex;flex-direction:column;line-height:1.35}
.ha-text strong{color:#fff;font-size:13.6px;font-weight:800}
.ha-text em{color:#9FB4CE;font-size:11.8px;font-style:normal}
.ha-arrow{color:#7FB0FF;font-size:14px;margin-left:4px}

.hero-visual{position:relative;perspective:1400px;transform:translate3d(0,0,0)}
.shot-main{
  border-radius:16px;overflow:hidden;background:#fff;
  border:1px solid rgba(255,255,255,.14);
  box-shadow:0 60px 120px -50px rgba(0,0,0,.9);
  transform:rotateY(-9deg) rotateX(4deg);
  animation:floatY 9s ease-in-out infinite;
}
.shot-main img{width:100%}
@keyframes floatY{
  0%,100%{transform:rotateY(-9deg) rotateX(4deg) translate3d(0,0,0)}
  50%{transform:rotateY(-9deg) rotateX(4deg) translate3d(0,-14px,0)}
}
.float-card{
  position:absolute;display:flex;align-items:center;gap:9px;
  padding:10px 14px;border-radius:12px;font-size:12.5px;font-weight:700;color:#EAF2FF;
  background:rgba(22,48,76,.94);border:1px solid rgba(127,176,255,.3);
  box-shadow:0 18px 40px -22px rgba(0,0,0,.9);
  animation:floatY2 7s ease-in-out infinite;
}
.fc-1{left:-26px;top:15%}
.fc-2{right:-16px;bottom:12%;animation-delay:-2.4s}
.fc-dot{width:8px;height:8px;border-radius:50%;background:var(--green);box-shadow:0 0 0 4px rgba(14,159,110,.22)}
.fc-bar{width:34px;height:8px;border-radius:4px;background:rgba(127,176,255,.22);overflow:hidden}
.fc-bar i{display:block;width:72%;height:100%;background:linear-gradient(90deg,#2563EB,#7FB0FF);border-radius:4px}
@keyframes floatY2{0%,100%{transform:translate3d(0,0,0)}50%{transform:translate3d(0,-9px,0)}}

.scroll-hint{position:absolute;left:50%;bottom:20px;transform:translateX(-50%);width:22px;height:34px;border:1.5px solid rgba(255,255,255,.24);border-radius:12px}
.scroll-hint span{position:absolute;left:50%;top:7px;width:3px;height:7px;border-radius:2px;background:rgba(255,255,255,.7);animation:wheel 1.9s ease-in-out infinite}
@keyframes wheel{0%{opacity:0;transform:translate(-50%,0)}30%{opacity:1}100%{opacity:0;transform:translate(-50%,12px)}}

/* ---------- 数字 ---------- */
.stats{background:var(--surface);border-bottom:1px solid var(--border)}
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;padding:34px 24px}
.stat{text-align:center}
.stat b{
  display:block;font-size:clamp(26px,3vw,38px);font-weight:800;letter-spacing:-.03em;
  background:linear-gradient(180deg,#2563EB,#1D4FD7);-webkit-background-clip:text;background-clip:text;color:transparent;
}
.stat span{display:block;font-size:12.8px;color:var(--text);font-weight:700}
.stat em{display:block;font-size:11.8px;color:var(--muted);font-style:normal;margin-top:2px}

/* ---------- 区块 ---------- */
.section{padding:92px 0}
.section-alt{background:var(--surface);border-top:1px solid var(--border);border-bottom:1px solid var(--border)}
.section-head{max-width:660px;margin:0 auto 52px;text-align:center}
.eyebrow{
  display:inline-block;font-size:11.5px;font-weight:800;letter-spacing:.16em;color:var(--blue);
  padding:5px 12px;border-radius:999px;background:#EAF1FF;margin-bottom:16px;
}
.section-head h2{font-size:clamp(23px,2.9vw,34px);margin-bottom:12px}
.section-head p{color:var(--muted);font-size:14.6px}

/* ---------- 功能详解 ---------- */
.feature-list{display:grid;gap:16px}
.feature{
  display:grid;grid-template-columns:290px minmax(0,1fr);gap:30px;
  background:var(--surface);border:1px solid var(--border);border-radius:18px;
  padding:26px 30px;box-shadow:var(--shadow-sm);
  transition:transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s;
}
.feature:hover{transform:translateY(-4px);box-shadow:var(--shadow-md);border-color:#CBD9F2}
.f-head{display:grid;grid-template-columns:auto 1fr;gap:12px 14px;align-content:start}
.f-no{
  grid-column:1 / -1;justify-self:start;
  font-size:12px;font-weight:800;letter-spacing:.1em;color:var(--blue);
  background:#EAF1FF;border-radius:7px;padding:3px 9px;
}
.f-icon{
  width:42px;height:42px;border-radius:12px;display:grid;place-items:center;
  color:var(--blue);background:linear-gradient(160deg,#EAF1FF,#DCE8FF);border:1px solid #D5E3FF;
}
.f-title h3{font-size:16.5px;margin-bottom:6px}
.f-title p{font-size:13.2px;color:var(--muted)}
.f-points{display:grid;gap:9px;align-content:start;padding-top:26px;border-top:1px dashed var(--border)}
.f-points li{position:relative;padding-left:20px;font-size:13.4px;color:#3C4757}
.f-points li::before{
  content:"";position:absolute;left:2px;top:9px;width:6px;height:6px;border-radius:50%;background:#B9CBF0;
}
.f-points b{color:var(--text);font-weight:700}

/* ---------- 界面 ---------- */
.tabs{display:flex;flex-wrap:wrap;justify-content:center;gap:8px;margin-bottom:24px}
.tab{
  height:38px;padding:0 18px;border-radius:999px;cursor:pointer;font-family:inherit;
  border:1px solid var(--border);background:var(--surface);color:var(--muted);
  font-size:13.4px;font-weight:700;
  transition:transform .22s var(--ease), color .2s, border-color .2s, background .2s, box-shadow .22s;
}
.tab:hover{color:var(--text);border-color:#CBD9F2;transform:translateY(-1px)}
.tab.is-active{color:#fff;background:linear-gradient(180deg,#3B76F6,#2563EB);border-color:transparent;box-shadow:0 10px 22px -16px rgba(37,99,235,.95)}

.shot-frame{
  margin:0;background:var(--surface);border:1px solid var(--border);
  border-radius:18px;padding:10px;box-shadow:var(--shadow-md);
}
.shot-bar{display:flex;align-items:center;gap:6px;padding:6px 8px 12px}
.shot-bar i{width:9px;height:9px;border-radius:50%;background:#E3E9F1}
.shot-bar i:nth-child(1){background:#F6C0BB}
.shot-bar i:nth-child(2){background:#F7DFB5}
.shot-bar i:nth-child(3){background:#BFE3CE}
.shot-bar span{margin-left:8px;font-size:11.5px;color:var(--muted);font-weight:600;letter-spacing:.02em}
.shot-frame img{
  width:100%;border-radius:10px;border:1px solid #EDF1F6;background:#fff;
  transition:opacity .28s var(--ease), transform .4s var(--ease);
}
.shot-frame img.swapping{opacity:0;transform:scale(.994)}
.shot-frame figcaption{text-align:center;font-size:12.4px;color:var(--muted);padding:14px 8px 6px}

.gallery-notes{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:20px}
.gn{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:14px 16px}
.gn b{display:block;font-size:12.5px;color:var(--text)}
.gn span{display:block;font-size:12.3px;color:var(--muted);margin-top:3px}

/* ---------- 数据 / 权限 ---------- */
.data-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;align-items:start}
.panel{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:26px 26px 22px;box-shadow:var(--shadow-sm)}
.panel h3{font-size:15.5px;margin-bottom:16px}
.file-table,.perm-table{width:100%;border-collapse:collapse;font-size:13px}
.file-table th{
  text-align:left;width:118px;white-space:nowrap;padding:9px 10px 9px 0;
  border-bottom:1px solid #EDF1F6;color:var(--text);font-weight:700;vertical-align:top;
}
.file-table td{padding:9px 0;border-bottom:1px solid #EDF1F6;color:var(--muted)}
.perm-table th,.perm-table td{padding:9px 8px;border-bottom:1px solid #EDF1F6;text-align:center}
.perm-table thead th{
  font-size:12px;font-weight:800;color:var(--muted);background:#F7F9FC;border-radius:0;
}
.perm-table thead th:first-child{text-align:left;border-radius:8px 0 0 0}
.perm-table thead th:last-child{border-radius:0 8px 0 0}
.perm-table td:first-child{text-align:left;color:#3C4757;width:46%}
.perm-table .y{color:var(--green);font-weight:800}
.perm-table .n{color:#B9C2CF}
.panel-note{margin-top:14px;font-size:12.2px;color:var(--muted);line-height:1.7}

/* ---------- 场景 ---------- */
.scene-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.scene{
  background:var(--bg);border:1px solid var(--border);border-radius:16px;padding:24px 22px;
  transition:transform .28s var(--ease), box-shadow .28s;
}
.scene:hover{transform:translateY(-4px);box-shadow:var(--shadow-sm)}
.scene-tag{
  display:inline-block;font-size:11.5px;font-weight:800;letter-spacing:.06em;color:#0B7C55;
  background:#E7F7F0;border-radius:999px;padding:4px 10px;margin-bottom:12px;
}
.scene h3{font-size:15.5px;margin-bottom:8px}
.scene p{font-size:13.2px;color:var(--muted)}

/* ---------- 步骤 ---------- */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.step{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:26px 24px;transition:transform .28s var(--ease), box-shadow .28s}
.step:hover{transform:translateY(-4px);box-shadow:var(--shadow-sm)}
.step-no{display:inline-block;font-size:12px;font-weight:800;letter-spacing:.1em;color:var(--blue);background:#EAF1FF;border-radius:8px;padding:4px 9px;margin-bottom:14px}
.step h3{font-size:16px;margin-bottom:8px}
.step p{font-size:13.2px;color:var(--muted)}

/* ---------- 作者 ---------- */
.author-section{
  position:relative;overflow:hidden;color:#fff;padding:88px 0;
  background:radial-gradient(900px 420px at 12% 0%,#16304F 0%,transparent 62%),
             linear-gradient(180deg,#0A1424,#0C1B2F 70%,#0A1424);
}
.author-card{
  position:relative;display:grid;grid-template-columns:200px minmax(0,1fr);gap:40px;
  background:rgba(255,255,255,.045);border:1px solid rgba(255,255,255,.1);
  border-radius:22px;padding:40px 42px;
}
.author-side{display:flex;flex-direction:column;align-items:flex-start;gap:20px}
.avatar-xl{
  width:112px;height:112px;border-radius:26px;display:grid;place-items:center;
  background:linear-gradient(160deg,#3B76F6,#1D4FD7);color:#fff;font-size:46px;font-weight:800;
  box-shadow:0 26px 50px -24px rgba(37,99,235,.95), inset 0 1px 0 rgba(255,255,255,.3);
}
.author-tags{display:flex;flex-wrap:wrap;gap:7px}
.author-tags li{
  font-size:11.5px;font-weight:700;color:#BBD3F7;letter-spacing:.03em;
  padding:4px 10px;border-radius:999px;background:rgba(127,176,255,.12);border:1px solid rgba(127,176,255,.24);
}
.author-eyebrow{
  display:inline-block;font-size:11.5px;font-weight:800;letter-spacing:.2em;color:#7FB0FF;margin-bottom:10px;
}
.author-main h2{font-size:clamp(28px,3.4vw,40px);letter-spacing:-.02em}
.author-role{color:#9FB4CE;font-size:13.6px;margin-top:8px}
.author-bio{color:#B7C7DD;font-size:13.8px;margin-top:16px;max-width:52em}
.author-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:24px}
.author-main .btn-line{color:#DCE8FA;border-color:rgba(255,255,255,.22)}
.author-main .btn-line:hover{background:rgba(255,255,255,.08);border-color:rgba(255,255,255,.36)}

/* ---------- 下载 ---------- */
.download-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:22px}
.dl-card{
  position:relative;display:flex;flex-direction:column;gap:13px;
  background:var(--surface);border:1px solid var(--border);border-radius:20px;
  padding:30px 28px;box-shadow:var(--shadow-sm);
  transition:transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s;
}
.dl-card:hover{transform:translateY(-5px);box-shadow:var(--shadow-md);border-color:#CBD9F2}
.dl-card-accent{
  border-color:#C9DBFF;background:linear-gradient(180deg,#F7FAFF,var(--surface) 42%);
  box-shadow:0 24px 50px -36px rgba(37,99,235,.65);
}
.dl-badge{align-self:flex-start;font-size:11.5px;font-weight:800;letter-spacing:.07em;padding:5px 11px;border-radius:999px;color:#1D4FD7;background:#EAF1FF}
.dl-badge-alt{color:#0B7C55;background:#E7F7F0}
.dl-card h3{font-size:19.5px}
.dl-desc{color:var(--muted);font-size:13.6px}
.dl-list{display:grid;gap:8px;margin:2px 0 8px}
.dl-list li{position:relative;padding-left:23px;font-size:13.2px;color:#3C4757}
.dl-list li::before{
  content:"";position:absolute;left:0;top:6px;width:15px;height:15px;border-radius:50%;
  background:#E7F7F0 url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%230E9F6E' stroke-width='3.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 13l4 4L19 7'/%3E%3C/svg%3E") center/9px no-repeat;
}
.dl-note{font-size:11.8px;color:var(--muted);text-align:center}
.dl-tip{text-align:center;color:var(--muted);font-size:12.8px;margin-top:24px}

/* ---------- FAQ ---------- */
.faq{display:grid;gap:10px}
.faq details{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:0 20px;transition:border-color .2s, box-shadow .2s}
.faq details[open]{border-color:#CBD9F2;box-shadow:var(--shadow-sm)}
.faq summary{
  cursor:pointer;padding:17px 0;font-weight:700;font-size:14.2px;list-style:none;
  display:flex;align-items:center;justify-content:space-between;gap:16px;
}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{
  content:"";flex:0 0 auto;width:9px;height:9px;
  border-right:2px solid var(--muted);border-bottom:2px solid var(--muted);
  transform:rotate(45deg);transition:transform .22s var(--ease);
}
.faq details[open] summary::after{transform:rotate(-135deg)}
.faq p{padding:0 0 17px;color:var(--muted);font-size:13.4px}

/* ---------- 页脚 ---------- */
.footer{background:var(--ink);color:#B7C7DD;padding:48px 0}
.footer-inner{display:grid;grid-template-columns:1fr auto;gap:22px 40px;align-items:center}
.footer-brand{display:flex;align-items:center;gap:12px}
.footer-brand strong{display:block;color:#fff;font-size:15px}
.footer-brand span{font-size:12.4px;color:#8296B0}
.footer-author{display:flex;align-items:center;gap:11px;justify-self:end}
.footer-author strong{display:block;color:#fff;font-size:13.6px}
.footer-author span{font-size:11.8px;color:#8296B0}
.footer-note{grid-column:1 / -1;margin:0;font-size:11.8px;color:#6F8299;border-top:1px solid rgba(255,255,255,.08);padding-top:18px}

/* ---------- 回到顶部 ---------- */
.to-top{
  position:fixed;right:20px;bottom:24px;z-index:80;width:44px;height:44px;
  display:grid;place-items:center;border-radius:12px;color:#fff;
  background:linear-gradient(180deg,#3B76F6,#1D4FD7);
  box-shadow:0 16px 30px -16px rgba(37,99,235,.9);
  opacity:0;transform:translate3d(0,10px,0);pointer-events:none;
  transition:opacity .25s var(--ease), transform .25s var(--ease);
}
.to-top.show{opacity:1;transform:none;pointer-events:auto}

/* ---------- 入场动画 ---------- */
/* 渐进增强：默认可见；仅当脚本正常执行（html 上加了 js-reveal）才做入场动画，
   这样脚本失效或被拦截时页面依然完整可读 */
.reveal{transition:opacity .7s var(--ease), transform .7s var(--ease)}
.js-reveal .reveal{opacity:0;transform:translate3d(0,24px,0)}
.js-reveal .reveal.in{opacity:1;transform:translate3d(0,0,0)}
.reveal[data-delay="1"]{transition-delay:.08s}
.reveal[data-delay="2"]{transition-delay:.16s}
.reveal[data-delay="3"]{transition-delay:.24s}
.reveal[data-delay="4"]{transition-delay:.32s}
.reveal[data-delay="5"]{transition-delay:.4s}

/* ---------- 响应式 ---------- */
@media (max-width:1060px){
  .hero-inner{grid-template-columns:1fr;gap:44px}
  .hero-visual{max-width:660px;margin:0 auto;width:100%}
  .shot-main{transform:none;animation:none}
  .fc-1{left:6px}
  .fc-2{right:6px}
  .feature{grid-template-columns:1fr;gap:18px;padding:24px 24px}
  .f-points{padding-top:18px}
  .scene-grid{grid-template-columns:repeat(2,1fr)}
  .data-grid{grid-template-columns:1fr}
  .author-card{grid-template-columns:1fr;gap:26px;padding:34px 30px}
  .author-side{flex-direction:row;align-items:center;gap:18px}
  .avatar-xl{width:84px;height:84px;border-radius:20px;font-size:34px}
}

@media (max-width:880px){
  .nav-links{
    position:fixed;inset:68px 0 auto 0;flex-direction:column;gap:0;margin:0;
    background:rgba(9,18,32,.985);
    border-bottom:1px solid rgba(255,255,255,.08);
    padding:6px 24px 16px;
    transform:translate3d(0,-10px,0);opacity:0;pointer-events:none;
    transition:transform .24s var(--ease), opacity .24s var(--ease);
  }
  .nav-links.open{transform:none;opacity:1;pointer-events:auto}
  .nav-links a{padding:14px 0;border-bottom:1px solid rgba(255,255,255,.07);font-size:14.6px}
  .nav-links a::after{display:none}
  .nav-cta{display:none}
  .nav-toggle{display:block}
  .nav-toggle.active span:nth-child(1){transform:translateY(7px) rotate(45deg)}
  .nav-toggle.active span:nth-child(2){opacity:0}
  .nav-toggle.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}
  .stats-grid{grid-template-columns:repeat(2,1fr);gap:22px 12px}
  .gallery-notes{grid-template-columns:1fr}
  .download-grid{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr}
  .footer-inner{grid-template-columns:1fr}
  .footer-author{justify-self:start}
}

@media (max-width:620px){
  .section{padding:66px 0}
  .wrap{padding:0 18px}
  .hero{padding:104px 0 62px}
  .hero h1{font-size:30px}
  .hero-actions{flex-direction:column;align-items:stretch}
  .hero-actions .btn{width:100%}
  .hero-meta{font-size:12px;gap:10px 14px}
  .hero-author{padding:8px 14px 8px 8px}
  .scene-grid{grid-template-columns:1fr}
  .tabs{gap:6px}
  .tab{height:34px;padding:0 13px;font-size:12.4px}
  .shot-frame{padding:7px;border-radius:14px}
  .dl-card{padding:24px 20px}
  .float-card{font-size:11.4px;padding:8px 11px}
  .scroll-hint{display:none}
  .author-card{padding:26px 20px}
  .avatar-xl{width:64px;height:64px;border-radius:16px;font-size:26px}
  .author-tags li{font-size:11px}
  .to-top{right:14px;bottom:16px;width:40px;height:40px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.js-reveal .reveal{opacity:1!important;transform:none!important}
  .progress{transition:none}
}