/* ═══ 檀光书院 · 样式（承 tanguangku 主站基因：宣纸 + 水墨 + 朱砂 + 金）═══ */
:root{
  --paper:#f2eee4; --paper-2:#e9e4d6; --card:#ffffff;
  --ink:#1a1712; --ink-soft:#5b5347; --ink-faint:#8c8373;
  --line:rgba(26,23,18,.14); --line-soft:rgba(26,23,18,.08);
  --cinnabar:#c0392b; --cinnabar-deep:#9c2a1e; --gold:#a9843f;
  --serif:"Noto Serif SC","Songti SC",serif;
  --latin:"Cormorant Garamond",serif;
  --sans:"Noto Sans SC","PingFang SC",sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--sans);background:var(--paper);color:var(--ink);
  -webkit-font-smoothing:antialiased;min-height:100dvh;display:flex;flex-direction:column}
::selection{background:var(--cinnabar);color:#fff5ef}
a{color:inherit;text-decoration:none}
img{display:block;max-width:100%}
.mono{letter-spacing:.34em;text-transform:uppercase;font-size:.66rem;font-weight:500;color:var(--ink-faint)}
.grain{position:fixed;inset:-50%;z-index:0;pointer-events:none;opacity:.05;mix-blend-mode:multiply;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E")}

/* 顶栏 */
.topbar{position:sticky;top:0;z-index:10;display:flex;justify-content:space-between;align-items:center;
  padding:.9rem clamp(1rem,4vw,3rem);background:color-mix(in srgb,var(--paper) 88%,transparent);
  backdrop-filter:blur(10px);border-bottom:1px solid var(--line-soft)}
.brand{display:flex;flex-direction:column;line-height:1.1}
.brand-cn{font-family:var(--serif);font-weight:900;font-size:1.25rem;letter-spacing:.18em}
.brand-en{font-family:var(--latin);font-size:.62rem;letter-spacing:.3em;color:var(--ink-faint)}
.topbar nav{display:flex;gap:1.1rem;align-items:center;font-size:.92rem}
.topbar nav a:hover{color:var(--cinnabar)}
.uname{color:var(--gold);font-weight:600}
.cta-mini{background:var(--cinnabar);color:#fff5ef;padding:.32rem .85rem;border-radius:2px;border:none;cursor:pointer;font-size:.88rem}
.cta-mini:hover{background:var(--cinnabar-deep)}
.ghost{color:var(--ink-faint)}
.ghost-mini{background:none;border:1px solid var(--line);border-radius:2px;padding:.2rem .6rem;cursor:pointer;color:var(--ink-faint)}

main{flex:1;position:relative;z-index:2;width:min(1080px,94vw);margin:0 auto;padding:2.4rem 0 4rem}

/* 首页 */
.hero{text-align:center;padding:3.2rem 1rem 2.6rem}
.hero h1{font-family:var(--serif);font-weight:900;font-size:clamp(1.9rem,4.6vw,3rem);letter-spacing:.14em;margin:.7rem 0}
.hero-sub{color:var(--ink-soft);line-height:1.9}
.hero-sub em,.blurb em{font-style:normal;color:var(--cinnabar)}
.course-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:1.2rem;margin-top:1rem}
.ccard{background:var(--card);border:1px solid var(--line-soft);border-radius:4px;padding:1.6rem 1.5rem 1.3rem;
  display:flex;flex-direction:column;gap:.8rem;transition:transform .25s ease,box-shadow .25s ease}
.ccard:hover{transform:translateY(-4px);box-shadow:0 14px 40px rgba(26,23,18,.10)}
.ccard.first{border-top:3px solid var(--cinnabar)}
.tag{display:inline-block;font-size:.72rem;letter-spacing:.12em;color:var(--cinnabar);border:1px solid currentColor;
  border-radius:2px;padding:.15rem .55rem;width:max-content}
.ccard h2{font-family:var(--serif);font-weight:700;font-size:1.28rem;letter-spacing:.06em}
.ccard .sub{color:var(--ink-faint);font-size:.86rem}
.blurb{color:var(--ink-soft);line-height:1.85;font-size:.93rem}
.go{margin-top:auto;color:var(--gold);font-size:.88rem}
.home-forum{margin-top:3.2rem}
.home-forum h3,.lesson-list h3,.adminbox h3{font-family:var(--serif);letter-spacing:.1em;margin-bottom:.9rem;
  border-left:3px solid var(--gold);padding-left:.6rem}

/* 帖子列表 */
.tlist{list-style:none}
.tlist li a{display:flex;align-items:center;gap:.7rem;padding:.68rem .4rem;border-bottom:1px solid var(--line-soft)}
.tlist li a:hover{background:color-mix(in srgb,var(--card) 60%,transparent)}
.bname{font-size:.72rem;color:var(--gold);border:1px solid var(--line);padding:.08rem .4rem;border-radius:2px;white-space:nowrap}
.tmeta{margin-left:auto;color:var(--ink-faint);font-size:.8rem;white-space:nowrap}
.empty{color:var(--ink-faint);padding:1rem 0}
.empty a{color:var(--cinnabar)}

/* 课程页 */
.course-head{padding:2.2rem 0 1.4rem;border-bottom:1px solid var(--line-soft);margin-bottom:1.6rem}
.course-head h1{font-family:var(--serif);font-weight:900;font-size:clamp(1.6rem,3.6vw,2.4rem);letter-spacing:.1em;margin:.5rem 0}
.course-cta{display:flex;align-items:center;gap:1.1rem;margin-top:1.2rem}
.price{font-family:var(--latin);font-size:1.7rem;color:var(--cinnabar);font-weight:600}
.price.big{font-size:2.2rem}
.cta{display:inline-block;background:var(--cinnabar);color:#fff5ef;padding:.6rem 1.7rem;border-radius:2px;
  border:none;cursor:pointer;font-size:1rem;letter-spacing:.15em}
.cta:hover{background:var(--cinnabar-deep)}
.owned{color:var(--gold);font-weight:600}
.pending{color:var(--ink-soft);background:var(--paper-2);padding:.5rem .9rem;border-radius:3px}
.lesson-list ol{list-style:none}
.lrow{display:flex;align-items:center;gap:.9rem;padding:.72rem .5rem;border-bottom:1px solid var(--line-soft)}
.lrow:hover{background:color-mix(in srgb,var(--card) 60%,transparent)}
.lrow.locked{opacity:.55}
.lseq{font-family:var(--latin);color:var(--gold);width:2rem}
.free{margin-left:auto;font-size:.74rem;color:var(--cinnabar);border:1px solid currentColor;padding:.1rem .5rem;border-radius:2px}
.lock{margin-left:auto;font-size:.8rem}

/* 观看页 */
.watch h1{font-family:var(--serif);letter-spacing:.08em;margin:.5rem 0 1.1rem}
.watch video{width:100%;max-height:70vh;background:#000;border-radius:4px}
.vplaceholder{padding:4.5rem 1rem;text-align:center;background:var(--paper-2);border-radius:4px;color:var(--ink-faint)}
.lesson-nav{display:flex;flex-wrap:wrap;gap:.45rem;margin-top:1.1rem}
.lnav{font-family:var(--latin);border:1px solid var(--line);border-radius:2px;padding:.25rem .6rem;font-size:.85rem}
.lnav.on{background:var(--cinnabar);color:#fff5ef;border-color:var(--cinnabar)}

/* 表单 */
.authbox,.buybox{max-width:430px;margin:2.5rem auto;background:var(--card);border:1px solid var(--line-soft);
  border-radius:4px;padding:2.2rem}
.authbox h1,.buybox h1{font-family:var(--serif);letter-spacing:.1em;margin-bottom:1.2rem}
label{display:block;margin-bottom:1rem;color:var(--ink-soft);font-size:.9rem}
input,textarea,select{width:100%;margin-top:.35rem;padding:.6rem .7rem;border:1px solid var(--line);
  border-radius:3px;background:var(--paper);font:inherit;color:var(--ink)}
input:focus,textarea:focus{outline:2px solid color-mix(in srgb,var(--cinnabar) 40%,transparent)}
.err{color:var(--cinnabar);margin-bottom:.9rem}
.switch{margin-top:1.1rem;color:var(--ink-faint);font-size:.88rem}
.switch a{color:var(--cinnabar)}
.qrcode{width:220px;margin:1rem auto;border:1px solid var(--line);border-radius:4px}
.paysteps p{margin:.7rem 0;line-height:1.8}
.tip{color:var(--ink-faint);font-size:.85rem}

/* 论坛 */
.forum h1,.thread h1{font-family:var(--serif);letter-spacing:.1em;margin:.4rem 0 1.2rem}
.boards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:.8rem;margin-bottom:1.6rem}
.board{background:var(--card);border:1px solid var(--line-soft);border-radius:4px;padding:1rem 1.1rem;
  display:flex;flex-direction:column;gap:.3rem}
.board.on{border-color:var(--cinnabar)}
.board b{font-family:var(--serif)}
.board span{color:var(--ink-faint);font-size:.82rem}
.board em{font-style:normal;color:var(--gold);font-size:.78rem}
.newthread{background:var(--card);border:1px solid var(--line-soft);border-radius:4px;padding:1.1rem;margin-bottom:1.4rem}
.newthread input,.newthread textarea{margin-bottom:.7rem}
.post{background:var(--card);border:1px solid var(--line-soft);border-radius:4px;padding:1rem 1.2rem;margin-bottom:.8rem}
.post.op{border-left:3px solid var(--gold)}
.phead{color:var(--gold);font-weight:600;font-size:.88rem;margin-bottom:.45rem}
.pbody{line-height:1.9;white-space:pre-wrap;color:var(--ink-soft)}
.replybox{margin-top:1.2rem}
.replybox textarea{margin-bottom:.7rem}

/* 管理 */
.adminbox table{width:100%;border-collapse:collapse;margin-bottom:1.6rem;font-size:.9rem;background:var(--card)}
.adminbox th,.adminbox td{border:1px solid var(--line-soft);padding:.5rem .7rem;text-align:left}
.adminbox th{background:var(--paper-2);font-weight:600}
.rowform{display:flex;gap:.6rem;margin-bottom:1.6rem}
.rowform input,.rowform select{width:auto;flex:1;margin:0}

/* 页脚 */
.foot{position:relative;z-index:2;background:#161310;color:#f2eee4;text-align:center;padding:1.6rem 1rem}
.foot-sub{color:#8c8373;font-size:.78rem;margin-top:.4rem}
@media(max-width:640px){
  .topbar nav{gap:.7rem;font-size:.84rem}
  .rowform{flex-direction:column}
}

/* ═══ v2 增补：logo/搜索/课程网格 ═══ */
.brand{flex-direction:row;align-items:center;gap:.6rem}
.logo{width:44px;height:44px;object-fit:contain}
.brand-txt{display:flex;flex-direction:column;line-height:1.1}
.mainnav{display:flex;gap:1.15rem;font-size:.95rem}
.mainnav a:hover{color:var(--cinnabar)}
.searchbox{display:flex;margin-left:auto;border:1px solid var(--line);border-radius:3px;overflow:hidden;background:var(--card)}
.searchbox input{border:none;margin:0;padding:.42rem .6rem;width:150px;background:transparent}
.searchbox input:focus{outline:none}
.searchbox button{border:none;background:var(--paper-2);padding:0 .8rem;cursor:pointer;color:var(--ink-soft)}
.searchbox button:hover{background:var(--cinnabar);color:#fff5ef}
.authnav{display:flex;gap:.9rem;align-items:center;font-size:.92rem}
.topbar{gap:1.4rem;flex-wrap:wrap}
.ccover{width:100%;aspect-ratio:16/9;object-fit:cover;border-radius:3px;border:1px solid var(--line-soft)}

.banner{background:linear-gradient(100deg,var(--cinnabar-deep),var(--cinnabar) 55%,var(--gold));color:#fff5ef;
  text-align:center;padding:1.05rem 1rem;border-radius:4px;font-family:var(--serif);letter-spacing:.2em;
  font-size:clamp(.95rem,2.2vw,1.25rem);margin-bottom:1.1rem}
.feat-row{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:.7rem;margin-bottom:2rem}
.feat{background:var(--card);border:1px solid var(--line-soft);border-radius:4px;padding:.8rem 1rem;
  display:flex;flex-direction:column;gap:.25rem}
.feat b{color:var(--cinnabar);font-size:.92rem}
.feat span{color:var(--ink-faint);font-size:.8rem}
.cblock{margin-bottom:2.6rem}
.cblock h3{font-family:var(--serif);letter-spacing:.08em;border-left:3px solid var(--gold);padding-left:.6rem;
  margin-bottom:1rem;display:flex;align-items:baseline;gap:.8rem;flex-wrap:wrap}
.cprice{color:var(--cinnabar);font-size:.85rem;font-weight:400}
.cblock .go{margin-left:auto;font-size:.85rem}
.vgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(215px,1fr));gap:1rem}
.vcard{background:var(--card);border:1px solid var(--line-soft);border-radius:4px;overflow:hidden;
  transition:transform .2s ease,box-shadow .2s ease}
.vcard:hover{transform:translateY(-3px);box-shadow:0 10px 28px rgba(26,23,18,.12)}
.vcard img{width:100%;aspect-ratio:16/9;object-fit:cover}
.vph{width:100%;aspect-ratio:16/9;background:var(--paper-2);display:flex;flex-direction:column;
  align-items:center;justify-content:center;color:var(--ink-faint);font-size:.8rem;gap:.2rem}
.vph span{font-family:var(--latin);font-size:1.6rem;color:var(--gold)}
.vcard p{padding:.6rem .75rem .7rem;font-size:.86rem;line-height:1.5}
.vcard .free{font-style:normal;color:var(--cinnabar);font-size:.72rem;border:1px solid currentColor;
  border-radius:2px;padding:.03rem .35rem;margin-left:.35rem;white-space:nowrap}
@media(max-width:860px){.searchbox{order:5;flex:1}.searchbox input{width:100%}}

.qrrow{display:flex;gap:1rem;justify-content:center}
.qrrow figure{text-align:center}
.qrrow figcaption{color:var(--ink-faint);font-size:.82rem;margin-top:.3rem}
.qrrow .qrcode{width:170px;margin:0}


/* ═══ v3 动效层 ═══ */
.rv{opacity:0;transform:translateY(22px);transition:opacity .7s cubic-bezier(.16,1,.3,1),transform .7s cubic-bezier(.16,1,.3,1)}
.rv-on{opacity:1;transform:none}
@media (prefers-reduced-motion: reduce){.rv{opacity:1;transform:none;transition:none}}
.topbar{transition:box-shadow .3s ease,background .3s ease}
.topbar.scrolled{box-shadow:0 8px 30px -12px rgba(26,23,18,.18)}
.hero h1{background:linear-gradient(120deg,var(--ink) 60%,var(--cinnabar));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.ccard,.vcard,.board{will-change:transform}
.ccard:hover .go{letter-spacing:.12em}
.go{transition:letter-spacing .3s ease}
.cta,.cta-mini{transition:background .25s ease,transform .18s ease,box-shadow .25s ease}
.cta:hover{transform:translateY(-1px);box-shadow:0 10px 24px -10px rgba(156,42,30,.6)}
.cta:active{transform:translateY(0)}
.lnav{transition:background .2s,color .2s,transform .2s}
.lnav:hover{transform:translateY(-2px)}
.banner{background-size:180% 100%;animation:bannerFlow 9s ease-in-out infinite alternate}
@keyframes bannerFlow{from{background-position:0% 0}to{background-position:100% 0}}
.watch video{box-shadow:0 24px 60px -24px rgba(0,0,0,.5)}
.brand .logo{transition:transform .5s cubic-bezier(.16,1,.3,1)}
.brand:hover .logo{transform:rotate(-8deg) scale(1.06)}

/* 加微信开通页 */
.wxbig{margin:22px auto;text-align:center}
.qrcode-big{width:min(320px,80vw);height:auto;border-radius:12px;border:1px solid rgba(198,161,91,.35);padding:8px;background:#fff}
.copyline{font-size:1.05rem;background:rgba(198,161,91,.12);border:1px dashed rgba(198,161,91,.5);padding:10px 14px;border-radius:10px;display:inline-block}


.opcell form{margin:2px}
.ghost-mini.danger{border-color:rgba(200,60,60,.6);color:#c85050}
.adminbox table{width:100%;font-size:.92rem}


.vwrap{position:relative}
.vwrap video{width:100%;display:block}


/* B站免费课指引 */
.freelink{color:#A3352C !important;font-weight:600;white-space:nowrap}
.freetag{font-size:.62rem;background:#A3352C;color:#fff;border-radius:4px;padding:1px 4px;margin-left:4px;vertical-align:2px}
.bili-banner{display:flex;align-items:center;gap:14px;margin:6px auto 22px;max-width:1060px;padding:13px 20px;border:1px solid rgba(163,53,44,.45);border-radius:12px;background:linear-gradient(100deg,rgba(163,53,44,.10),rgba(198,161,91,.16));text-decoration:none;transition:transform .2s}
.bili-banner:hover{transform:translateY(-2px)}
.bb-tag{background:#A3352C;color:#fff;font-size:.78rem;padding:3px 9px;border-radius:6px;flex:none}
.bb-txt{color:#4a3826;font-size:.95rem;font-weight:500;flex:1}
.bb-go{color:#A3352C;font-size:.9rem;font-weight:600;flex:none}


.dl-courseware{display:inline-block;margin:10px 0 4px;padding:10px 18px;border:1px solid rgba(163,53,44,.5);border-radius:10px;background:rgba(163,53,44,.08);color:#A3352C;font-weight:600;text-decoration:none}
.dl-courseware:hover{background:rgba(163,53,44,.16)}

.dlnav{background:#A3352C;color:#fff !important;padding:5px 13px;border-radius:8px;font-size:.88rem;white-space:nowrap}
.dlnav:hover{background:#8d2d25}

.dlpage{max-width:860px;margin:0 auto}
.dlcard{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:22px 26px;border:1px solid rgba(163,53,44,.35);border-radius:14px;background:rgba(198,161,91,.08);margin:18px 0}
.dlcard h3{margin:0 0 6px}
.dlcard p{margin:0;color:#6b5335;font-size:.92rem}
.dlact{flex:none}