:root{
  --bg:#11151b;
  --bg-alt:#171d25;
  --card:#1b222b;
  --line:#2a323d;
  --text:#eef1f5;
  --text-dim:#8b95a3;
  --accent:#c6ff3d;   /* chuyển động / năng lượng */
  --accent-2:#ff5a5f; /* cường độ / tác động */
  --accent-3:#3dd8ff; /* thông tin khoa học */
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  line-height:1.55;
}

.display{
  font-family:"Arial Black","Arial Narrow",Impact,sans-serif;
  text-transform:uppercase;
  letter-spacing:0.02em;
}

/* ===== Top bar ===== */
.topbar{
  position:sticky;top:0;z-index:20;
  background:rgba(17,21,27,0.92);
  backdrop-filter:blur(6px);
  border-bottom:1px solid var(--line);
  padding:14px 24px;
  display:flex;align-items:center;justify-content:space-between;
  flex-wrap:wrap;gap:10px;
}
.topbar a{color:var(--text);text-decoration:none;}
.brand{font-size:20px;font-weight:900;}
.brand-logo{display:flex;align-items:center;}
.brand-logo img{height:40px;width:auto;border-radius:6px;background:#fff;padding:2px 6px;}
.brand span{color:var(--accent);}
.nav{display:flex;gap:6px;flex-wrap:wrap;}
.nav a{
  font-size:13px;padding:8px 12px;border-radius:999px;
  border:1px solid var(--line);color:var(--text-dim);
}
.nav a.active,.nav a:hover{border-color:var(--accent);color:var(--accent);}

/* ===== Hero ===== */
.hero{
  padding:56px 24px 32px;
  max-width:980px;margin:0 auto;
  border-bottom:1px solid var(--line);
}
.eyebrow{
  color:var(--accent);font-size:12px;letter-spacing:0.18em;
  text-transform:uppercase;font-weight:700;margin-bottom:10px;
}
.hero h1{
  font-size:clamp(30px,5vw,52px);
  margin:0 0 12px;line-height:1.05;
}
.hero p{color:var(--text-dim);max-width:640px;font-size:16px;}

/* ===== Category grid on index ===== */
.grid{
  max-width:980px;margin:0 auto;padding:32px 24px 80px;
  display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));
  gap:16px;
}
.cat-card{
  background:var(--card);border:1px solid var(--line);
  border-radius:14px;padding:22px;text-decoration:none;color:var(--text);
  position:relative;overflow:hidden;transition:transform .15s ease,border-color .15s ease;
}
.cat-card:hover{transform:translateY(-3px);border-color:var(--accent);}
.cat-card .num{
  font-size:12px;color:var(--text-dim);letter-spacing:.12em;
}
.cat-card h3{margin:8px 0 6px;font-size:22px;}
.cat-card p{margin:0;color:var(--text-dim);font-size:13.5px;}
.cat-card .tag{
  display:inline-block;margin-top:12px;font-size:11px;color:var(--accent-3);
  border:1px solid var(--accent-3);padding:3px 8px;border-radius:999px;
}

/* ===== Category page ===== */
.cat-hero{padding:44px 24px 20px;max-width:980px;margin:0 auto;}
.cat-hero h1{font-size:clamp(28px,4.5vw,44px);margin:0 0 10px;}
.cat-hero p{color:var(--text-dim);max-width:640px;}

.exercise{
  max-width:980px;margin:0 auto 28px;padding:0 24px;
}
.exercise-card{
  background:var(--card);border:1px solid var(--line);border-radius:16px;
  display:grid;grid-template-columns:260px 1fr;overflow:hidden;
}
@media (max-width:760px){.exercise-card{grid-template-columns:1fr;}}

.viz{
  background:radial-gradient(circle at 30% 20%,#202a35,#11151b 70%);
  display:flex;align-items:center;justify-content:center;
  padding:18px;border-right:1px solid var(--line);
}
@media (max-width:760px){.viz{border-right:none;border-bottom:1px solid var(--line);}}
.viz svg{width:100%;max-width:220px;height:auto;}
.viz img{width:100%;max-width:220px;height:auto;border-radius:8px;display:block;}
.crossfade{position:relative;width:100%;height:100%;min-height:120px;border-radius:8px;overflow:hidden;}
.crossfade img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;}
.crossfade img.cf-a{animation:cfA 3.2s ease-in-out infinite;}
.crossfade img.cf-b{animation:cfB 3.2s ease-in-out infinite;}
@keyframes cfA{0%,45%{opacity:1}55%,100%{opacity:0}}
@keyframes cfB{0%,45%{opacity:0}55%,100%{opacity:1}}
.crossfade.big{height:320px;}
.photo-credit{font-size:11px;color:var(--text-dim);text-align:center;margin:6px 0 0;}
.why-section{max-width:980px;margin:0 auto;padding:12px 24px 8px;}
.why-grid{
  display:grid;grid-template-columns:repeat(4,1fr);gap:16px;
}
@media (max-width:800px){.why-grid{grid-template-columns:repeat(2,1fr);}}
.why-card{
  background:var(--card);border:1px solid var(--line);border-radius:14px;
  padding:18px;
}
.why-num{color:var(--accent);font-weight:900;font-size:13px;letter-spacing:.1em;margin-bottom:8px;}
.why-card h4{margin:0 0 8px;font-size:15px;}
.why-card p{margin:0;color:var(--text-dim);font-size:13px;line-height:1.5;}

.map-section{
  max-width:980px;margin:0 auto;padding:0 24px 40px;
}
.map-section iframe{
  border-radius:12px;border:1px solid var(--line);display:block;
}
.map-directions-btn{
  display:inline-block;margin-top:14px;
  background:var(--accent);color:#0b1220;font-weight:800;
  padding:12px 20px;border-radius:999px;text-decoration:none;font-size:14px;
}

.gallery-section{max-width:980px;margin:0 auto;padding:0 24px 20px;}
.gallery-section h3{
  font-size:15px;color:var(--accent-3);margin:28px 0 12px;
  text-transform:uppercase;letter-spacing:.06em;
}
.gallery-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:12px;
}
.gallery-grid img{
  width:100%;height:180px;object-fit:cover;border-radius:10px;
  border:1px solid var(--line);
}
@media (max-width:700px){.gallery-grid{grid-template-columns:repeat(2,1fr);}}

.brand-logo img{height:40px;display:block;}
footer.brand-footer{
  background:var(--bg-alt);border-top:1px solid var(--line);
  padding:36px 24px 20px;margin-top:20px;
}
.brand-footer-inner{
  max-width:980px;margin:0 auto;display:grid;
  grid-template-columns:1.2fr 1fr 1fr;gap:24px;text-align:left;
}
@media (max-width:700px){.brand-footer-inner{grid-template-columns:1fr;}}
.bf-col p{margin:4px 0;color:var(--text-dim);font-size:13.5px;}
.bf-col a{color:var(--accent-3);text-decoration:none;}
.bf-logo{height:52px;margin-bottom:8px;}
.bf-slogan{color:var(--accent) !important;font-weight:700;font-size:13px !important;}
.bf-note{
  max-width:980px;margin:24px auto 0;padding-top:16px;
  border-top:1px solid var(--line);color:var(--text-dim);
  font-size:12px;text-align:center;
}

.viz .ph-lg{
  color:var(--text-dim);font-size:12.5px;text-align:center;padding:26px 14px;
  border:1px dashed var(--line);border-radius:10px;line-height:1.5;
}

.info{padding:22px 24px;}
.info .idx{color:var(--accent);font-weight:800;font-size:12px;letter-spacing:.14em;}
.info h2{margin:6px 0 12px;font-size:24px;}

.badges{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:14px;}
.badge{
  font-size:11.5px;padding:4px 10px;border-radius:999px;border:1px solid var(--line);
  color:var(--text-dim);
}
.badge.primary{border-color:var(--accent-2);color:var(--accent-2);}

.section-title{
  font-size:11px;letter-spacing:.14em;text-transform:uppercase;
  color:var(--accent-3);margin:16px 0 6px;font-weight:700;
}
.info ol,.info ul{margin:0;padding-left:18px;color:var(--text);font-size:14.5px;}
.info li{margin-bottom:5px;}
.effects{color:var(--text-dim);font-size:14.5px;margin:0;}
.caution{
  margin-top:14px;font-size:13px;color:var(--accent-2);
  border-left:2px solid var(--accent-2);padding-left:10px;
}

footer{
  text-align:center;color:var(--text-dim);font-size:12.5px;
  padding:30px 24px 60px;
}

@media (prefers-reduced-motion:reduce){
  *{animation:none !important;}
}

/* ===== Library toolbar & grid ===== */
.lib-hero{padding:44px 24px 8px;max-width:1100px;margin:0 auto;}
.lib-hero h1{font-size:clamp(28px,4.5vw,44px);margin:0 0 10px;}
.lib-hero p{color:var(--text-dim);max-width:640px;}

.toolbar{
  max-width:1100px;margin:18px auto 0;padding:0 24px;
  display:flex;flex-wrap:wrap;gap:10px;position:sticky;top:64px;z-index:15;
}
.toolbar input[type="text"]{
  flex:1 1 220px;background:var(--card);border:1px solid var(--line);
  color:var(--text);padding:10px 14px;border-radius:10px;font-size:14px;
}
.toolbar select{
  background:var(--card);border:1px solid var(--line);color:var(--text);
  padding:10px 12px;border-radius:10px;font-size:13.5px;
}
.toolbar .count{
  align-self:center;color:var(--text-dim);font-size:12.5px;margin-left:auto;
}

.lib-grid{
  max-width:1100px;margin:0 auto;padding:20px 24px 80px;
  display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));
  gap:14px;
}
.lib-card{
  background:var(--card);border:1px solid var(--line);border-radius:14px;
  overflow:hidden;cursor:pointer;transition:border-color .15s ease, transform .15s ease;
  display:flex;flex-direction:column;
}
.lib-card:hover{border-color:var(--accent);transform:translateY(-2px);}
.lib-thumb{
  aspect-ratio:4/3;background:radial-gradient(circle at 30% 20%,#202a35,#11151b 70%);
  display:flex;align-items:center;justify-content:center;overflow:hidden;
}
.lib-thumb img{width:100%;height:100%;object-fit:cover;}
.lib-thumb .ph{
  color:var(--text-dim);font-size:11.5px;text-align:center;padding:10px;
  border:1px dashed var(--line);border-radius:10px;margin:14px;
}
.lib-body{padding:12px 14px 14px;}
.lib-body h4{margin:0 0 6px;font-size:14.5px;line-height:1.3;}
.lib-tags{display:flex;flex-wrap:wrap;gap:5px;}
.lib-tags span{
  font-size:10.5px;padding:2px 7px;border-radius:999px;border:1px solid var(--line);
  color:var(--text-dim);
}
.lib-tags span.tprimary{border-color:var(--accent-3);color:var(--accent-3);}

.pagination{
  max-width:1100px;margin:0 auto;padding:0 24px 40px;
  display:flex;justify-content:center;gap:8px;flex-wrap:wrap;
}
.pagination button{
  background:var(--card);border:1px solid var(--line);color:var(--text);
  padding:7px 13px;border-radius:8px;font-size:13px;cursor:pointer;
}
.pagination button.active{border-color:var(--accent);color:var(--accent);}
.pagination button:disabled{opacity:.4;cursor:default;}

/* ===== Modal chi tiết ===== */
.modal-overlay{
  position:fixed;inset:0;background:rgba(6,8,11,0.75);
  display:flex;align-items:flex-start;justify-content:center;
  padding:40px 16px;z-index:100;overflow-y:auto;
}
.modal-box{
  background:var(--card);border:1px solid var(--line);border-radius:16px;
  max-width:640px;width:100%;overflow:hidden;
}
.modal-media{
  background:radial-gradient(circle at 30% 20%,#202a35,#11151b 70%);
  display:flex;align-items:center;justify-content:center;min-height:220px;
}
.modal-media img{width:100%;max-height:320px;object-fit:contain;}
.modal-content{padding:22px 24px 26px;}
.modal-content h3{margin:0 0 10px;font-size:22px;}
/* Bộ nút liên hệ nổi: Gọi điện / Zalo / Messenger.
   Đặt ở góc dưới BÊN TRÁI để không chồng lên nút chat AI (góc dưới bên phải). */
.fab-stack{
  position:fixed;left:20px;bottom:20px;z-index:50;
  display:flex;flex-direction:column;gap:10px;align-items:flex-start;
}
.fab-btn{
  display:flex;align-items:center;gap:10px;
  color:#fff;text-decoration:none;
  padding:13px 20px 13px 15px;border-radius:999px;
  font-weight:800;font-size:14.5px;line-height:1;white-space:nowrap;
  box-shadow:0 6px 20px rgba(0,0,0,.35);
  transition:transform .15s ease;
}
.fab-btn:hover{transform:translateY(-2px) scale(1.03);}
.fab-btn svg{width:24px;height:24px;flex:none;}
.fab-call{background:#16a34a;animation:fabPulse 2.4s ease-in-out infinite;}
.fab-zalo{background:#0068ff;}
.fab-mess{background:var(--accent-2);}
@keyframes fabPulse{
  0%,100%{box-shadow:0 6px 20px rgba(22,163,74,.5);}
  50%{box-shadow:0 6px 30px rgba(22,163,74,.85);}
}
@media (max-width:520px){
  .fab-stack{left:14px;bottom:14px;gap:8px;}
  .fab-btn span{display:none;}
  .fab-btn{padding:14px;border-radius:50%;}
}

.modal-close{
  float:right;background:none;border:1px solid var(--line);color:var(--text-dim);
  border-radius:8px;padding:5px 11px;cursor:pointer;font-size:13px;
}
.modal-content .badges{margin-bottom:14px;}

/* ===== Theory page ===== */
.theory{max-width:760px;margin:0 auto;padding:44px 24px 80px;}
.theory h1{font-size:clamp(28px,4.5vw,42px);margin:0 0 22px;}
.theory h2{
  font-size:20px;color:var(--accent);margin:34px 0 10px;
  border-left:3px solid var(--accent);padding-left:12px;
}
.theory p{color:var(--text);font-size:15px;margin:0 0 12px;}
.theory ul{color:var(--text);font-size:15px;padding-left:20px;}
.theory li{margin-bottom:6px;}
.theory .note{
  margin-top:10px;font-size:13.5px;color:var(--text-dim);
  border-left:2px solid var(--accent-3);padding-left:12px;
}

/* ===== Giải phẫu / Khoa học vận động ===== */
.toc{display:flex;flex-wrap:wrap;gap:8px;margin:18px 0 6px;}
.toc a{font-size:12.5px;padding:6px 12px;border-radius:999px;border:1px solid var(--line);color:var(--text-dim);text-decoration:none;}
.toc a:hover{border-color:var(--accent);color:var(--accent);}

.plane-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px;margin:14px 0 20px;}
.plane-card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:16px;}
.plane-card .pnum{color:var(--accent-3);font-weight:900;font-size:11px;letter-spacing:.12em;text-transform:uppercase;}
.plane-card h4{margin:6px 0 6px;font-size:15px;}
.plane-card p{margin:0;color:var(--text-dim);font-size:13px;}

.kinesio-table{width:100%;border-collapse:collapse;margin:10px 0 22px;font-size:13.5px;}
.kinesio-table th,.kinesio-table td{border-bottom:1px solid var(--line);padding:8px 10px;text-align:left;vertical-align:top;}
.kinesio-table th{color:var(--accent-3);font-size:11.5px;text-transform:uppercase;letter-spacing:.05em;}
.kinesio-table td{color:var(--text-dim);}
.kinesio-table td strong{color:var(--text);}
@media (max-width:640px){.kinesio-table{font-size:12.5px;} .kinesio-table th,.kinesio-table td{padding:6px;}}

.anatomy-grid{max-width:980px;margin:0 auto;padding:6px 24px 10px;display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:16px;}
.anatomy-card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:20px;}
.anatomy-card h3{margin:0 0 2px;font-size:18px;}
.anatomy-card .latin{color:var(--text-dim);font-size:12px;font-style:italic;margin:0 0 12px;}
.anatomy-card dl{margin:0;}
.anatomy-card dt{color:var(--accent-3);font-weight:700;font-size:10.5px;text-transform:uppercase;letter-spacing:.06em;margin-top:10px;}
.anatomy-card dd{margin:2px 0 0;color:var(--text);font-size:13.5px;}
.anatomy-card .go-link{display:inline-block;margin-top:14px;font-size:13px;color:var(--accent);font-weight:700;text-decoration:none;}
.anatomy-card .go-link:hover{text-decoration:underline;}

/* ===== Chatbox AI tư vấn ===== */
.pg-chat-fab{
  position:fixed;right:20px;bottom:90px;z-index:49;
  display:flex;align-items:center;gap:8px;
  background:var(--accent);color:#0b1220;border:none;cursor:pointer;
  padding:12px 18px;border-radius:999px;font-weight:800;font-size:14px;
  box-shadow:0 6px 20px rgba(198,255,61,.4);
}
@media (max-width:520px){ .pg-chat-fab span{display:none;} .pg-chat-fab{padding:14px;border-radius:50%;} }

.pg-chat-panel{
  position:fixed;right:20px;bottom:150px;z-index:60;
  width:340px;max-width:90vw;height:440px;max-height:70vh;
  background:var(--bg-alt);border:1px solid var(--line);border-radius:16px;
  flex-direction:column;overflow:hidden;box-shadow:0 12px 40px rgba(0,0,0,.5);
}
.pg-chat-header{
  display:flex;justify-content:space-between;align-items:center;
  padding:12px 14px;background:var(--card);border-bottom:1px solid var(--line);
  font-weight:800;font-size:14px;
}
.pg-chat-header button{background:none;border:none;color:var(--text-dim);cursor:pointer;font-size:14px;}
.pg-chat-body{flex:1;overflow-y:auto;padding:12px;display:flex;flex-direction:column;gap:8px;}
.pg-msg{padding:8px 12px;border-radius:12px;font-size:13.5px;line-height:1.4;max-width:85%;}
.pg-msg-bot{background:var(--card);border:1px solid var(--line);align-self:flex-start;}
.pg-msg-user{background:var(--accent);color:#0b1220;align-self:flex-end;font-weight:600;}
.pg-chat-input-row{display:flex;gap:6px;padding:10px;border-top:1px solid var(--line);}
.pg-chat-input-row input{
  flex:1;background:var(--bg);border:1px solid var(--line);border-radius:999px;
  padding:8px 14px;color:var(--text);font-size:13.5px;
}
.pg-chat-input-row button{
  background:var(--accent);color:#0b1220;border:none;border-radius:999px;
  padding:8px 16px;font-weight:800;cursor:pointer;font-size:13px;
}
.pg-chat-disclaimer{font-size:10.5px;color:var(--text-dim);text-align:center;padding:0 10px 8px;margin:0;}

/* ===== Thẻ gợi ý bài tập trong chatbox ===== */
.pg-cards{
  display:grid;grid-template-columns:repeat(2,1fr);gap:8px;margin-top:4px;
}
.pg-card{
  display:block;text-decoration:none;color:var(--text);
  background:var(--card);border:1px solid var(--line);border-radius:10px;
  overflow:hidden;
}
.pg-card-thumb{
  width:100%;aspect-ratio:1/1;background:#11151b;
  display:flex;align-items:center;justify-content:center;
}
.pg-card-thumb img{width:100%;height:100%;object-fit:cover;}
.pg-card-noimg{font-size:10.5px;color:var(--text-dim);}
.pg-card-name{
  font-size:11px;padding:5px 7px;line-height:1.3;
  color:var(--text);
}