:root{font-family:Inter,"PingFang SC","Microsoft YaHei",Arial,sans-serif;color:#14213d;background:#f7f9fd}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:#f7f9fd}
nav{position:sticky;top:0;z-index:10;height:72px;display:flex;align-items:center;justify-content:space-between;padding:0 max(24px,8vw);background:rgba(255,255,255,.86);backdrop-filter:blur(14px);border-bottom:1px solid #e8edf6}
nav b{font-size:18px;color:#173176}
nav div{display:flex;align-items:center;gap:20px}
nav a{color:#4b5b76;text-decoration:none;font-weight:700}
nav .admin-link{border:1px solid #dbe3ef;border-radius:999px;padding:9px 13px;background:#fff;color:#165bd8;box-shadow:none}
button,.button{display:inline-flex;align-items:center;justify-content:center;border:0;border-radius:14px;padding:13px 18px;font-weight:800;cursor:pointer;text-decoration:none}
.primary,nav button,.full{background:linear-gradient(135deg,#1463ff,#6c4df6);color:#fff;box-shadow:0 12px 30px rgba(20,99,255,.22)}
.secondary{background:#fff;color:#172033;border:1px solid #dbe3ef;box-shadow:none}
main{max-width:1200px;margin:auto;padding:0 24px}
.hero{display:grid;grid-template-columns:1.08fr .92fr;gap:54px;align-items:center;padding:86px 0 70px}
.eyebrow{display:inline-flex;color:#165bd8;background:#eaf2ff;border-radius:999px;padding:8px 13px;font-weight:900;letter-spacing:.04em;font-size:13px}
.hero h1{font-size:56px;line-height:1.08;margin:22px 0 18px;letter-spacing:-1.8px}
.hero p,.section-title p{color:#516078;font-size:19px;line-height:1.8}
.hero-actions{display:flex;gap:14px;flex-wrap:wrap;margin-top:28px}
.facts{font-size:14px!important;margin-top:18px;color:#697891!important}
.preview{display:block;width:100%;text-align:left;background:linear-gradient(180deg,#fff,#fbfcff);border:1px solid #e0e7f2;border-radius:28px;padding:30px;box-shadow:0 24px 60px rgba(20,36,70,.12);color:#14213d;transition:.18s transform,.18s box-shadow,.18s border-color}
.preview:hover{transform:translateY(-3px);border-color:#b8cbef;box-shadow:0 28px 70px rgba(20,36,70,.16)}
.preview:focus-visible{outline:3px solid rgba(20,99,255,.28);outline-offset:4px}
.preview small{color:#165bd8;font-weight:900}
.preview p{background:#f1f5ff;border-radius:16px;padding:14px 16px;font-size:15px!important;line-height:1.7}
.preview .user{background:#eefaf8;margin-left:34px}
.preview-cta{display:inline-flex;margin-top:8px;color:#165bd8;font-weight:950}
.section{padding:58px 0}
.section-title{margin-bottom:28px}
.section-title h2{font-size:36px;margin:14px 0 8px}
.course-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.course-card{background:#fff;border:1px solid #e2e8f0;border-radius:24px;padding:22px;min-height:248px;box-shadow:0 12px 32px rgba(20,36,70,.06);transition:.18s transform,.18s box-shadow}
.course-card:hover{transform:translateY(-3px);box-shadow:0 20px 45px rgba(20,36,70,.10)}
.course-card b{color:#5b5ff0;font-size:13px}
.course-card h3{font-size:21px;margin:12px 0}
.course-card p{color:#637088;line-height:1.65}
.course-meta{display:flex;justify-content:space-between;gap:12px;align-items:center;margin-top:16px}
.price{font-weight:950;color:#ff7a00;font-size:20px}
.linkish{color:#165bd8;font-weight:900}
.path{margin:34px -24px 0;padding:68px 24px;background:linear-gradient(135deg,#eef4ff,#fff7e8);border-radius:32px}
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.step-card{display:block;text-align:left;background:#fff;color:#14213d;border:1px solid #e2e8f0;border-radius:22px;padding:24px;box-shadow:none;transition:.18s transform,.18s box-shadow}
.step-card:hover{transform:translateY(-3px);box-shadow:0 20px 45px rgba(20,36,70,.10)}
.step-card i{display:block;color:#165bd8;font-style:normal;font-weight:950;margin-bottom:12px}
.step-card b{display:block;font-size:20px}
.step-card p{color:#637088;line-height:1.7}
.step-card span{display:inline-flex;margin-top:8px;color:#165bd8;font-weight:900}
#chat,#course-panel,#path-panel,#admin-login{position:fixed;right:24px;bottom:24px;width:min(410px,calc(100vw - 48px));max-height:82vh;overflow:auto;background:#fff;border:1px solid #dfe5f4;border-radius:22px;padding:18px;box-shadow:0 24px 70px rgba(20,33,61,.22);z-index:20}
#course-panel,#path-panel{right:454px}
#admin-login{top:96px;bottom:auto}
#floating-chat{position:fixed;right:24px;bottom:24px;z-index:15;border-radius:999px;padding:15px 20px;background:linear-gradient(135deg,#1463ff,#6c4df6);color:#fff;box-shadow:0 18px 40px rgba(20,99,255,.28)}
#chat:not([hidden])~#floating-chat{display:none}
aside header{display:flex;justify-content:space-between;align-items:center;font-weight:900;margin-bottom:12px}
aside header button{padding:4px 10px;border-radius:10px;box-shadow:none;background:#eef3ff;color:#18315c}
.admin-login-note{margin:4px 0 14px;color:#5e6b82;line-height:1.7}
.admin-login-error{margin:12px 0 0;color:#c2410c;background:#fff7ed;border:1px solid #fed7aa;border-radius:12px;padding:10px 12px}
.detail-block{padding:12px 0;border-top:1px solid #edf1f7}
.detail-block:first-child{border-top:0}
.detail-block h4{margin:0 0 8px;color:#172033}
.detail-block p,.detail-block li{color:#5e6b82;line-height:1.7}
.detail-block ul{margin:0;padding-left:18px}
.related-list{display:grid;gap:8px}
.related-course{display:block;width:100%;text-align:left;background:#f6f8ff;color:#172033;border:1px solid #e1e8f5;border-radius:14px;padding:12px;box-shadow:none}
.related-course strong{display:block}
.related-course span{display:block;margin-top:4px;color:#64748b;font-size:13px}
.full{width:100%;margin-top:8px}
#messages{min-height:180px;padding:8px 0}
#messages p{background:#f1f5ff;border-radius:12px;padding:10px 12px;font-size:14px;line-height:1.6}
.msg-user{background:#eefaf8!important}
form{display:flex;gap:8px}
input{flex:1;border:1px solid #d7ddeb;border-radius:12px;padding:12px;min-width:0}
footer{text-align:center;color:#6b7280;padding:44px 24px}
footer a{color:#6b7280}
@media(max-width:980px){
  .hero,.course-grid,.steps{grid-template-columns:1fr}
  .hero h1{font-size:40px}
  nav{align-items:flex-start;height:auto;padding-top:14px;padding-bottom:14px;gap:12px;flex-direction:column}
  #course-panel,#path-panel{right:24px;bottom:88px}
  #admin-login{top:110px;right:18px}
  #floating-chat{right:18px;bottom:18px}
}