/* main.css — SuperEdu modern tech style (blue→purple gradient) */
:root{
  --brand-1:#4B89FF;
  --brand-2:#6E4BFF;
  --grad: linear-gradient(135deg,var(--brand-1) 0%,var(--brand-2) 100%);
  --bg:#F7F9FF;
  --muted:#6B7280;
  --text:#0A0A0A;
  --card:#ffffff;
  --glass: rgba(255,255,255,0.65);
  --radius:14px;
  --maxw:1200px;
}

/* Reset basics */
*{box-sizing:border-box}
html,body{height:100%;margin:0;padding:0;font-family:Inter, "Segoe UI", Roboto, "Helvetica Neue", Arial; background:var(--bg); color:var(--text); -webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}

/* NAV */
nav#topNav{position:fixed;top:0;left:0;width:100%;z-index:60;transition:all .25s ease}
nav#topNav.nav--transparent{background:transparent;border-bottom:0}
nav#topNav.nav--solid{background:rgba(255,255,255,0.96);border-bottom:1px solid #e6eaf3;box-shadow:0 6px 18px rgba(20,30,60,0.04);backdrop-filter: blur(6px)}
nav .nav-inner{max-width:var(--maxw);margin:0 auto;display:flex;align-items:center;justify-content:space-between;padding:14px 20px}
.brand{display:flex;align-items:center;gap:12px}
.logo-img{height:36px;width:auto;border-radius:8px;padding:4px;background:#fff}
.brand-text{font-weight:700;color:var(--brand-2);font-size:18px;line-height:1;transform:translateY(-2px)} /* lift text a bit to align with logo */

.menu{display:flex;gap:8px;align-items:center}
.menu a{padding:6px 12px;border-radius:8px;font-weight:600;color:#222;transition:all .15s}
.menu a:hover{color:var(--brand-1);transform:translateY(-1px)}
.nav-right{display:flex;align-items:center;gap:12px}
.lang-toggle{padding:8px 12px;border-radius:10px;border:1px solid rgba(0,0,0,0.08);background:#fff;cursor:pointer}
.hamburger{display:none;background:none;border:0;padding:6px;cursor:pointer}
.hamburger span{display:block;width:22px;height:2px;background:#222;margin:4px 0;border-radius:2px;transition:all .2s}

/* mobile menu (slide) */
.mobile-menu{display:none;max-width:var(--maxw);margin:0 auto;padding:10px 20px;}

/* HERO */
.hero{max-width:var(--maxw);margin:0 auto;padding:140px 20px 80px;display:grid;grid-template-columns:1fr 460px;gap:36px;align-items:center}
.hero-left{}
.hero-title{font-size:44px;line-height:1.08;margin:0 0 12px;font-weight:800}
.hero-desc{color:var(--muted);margin:0 0 18px;font-size:16px;max-width:640px}
.hero-ctas{display:flex;gap:12px;align-items:center;flex-wrap:wrap}
.btn{cursor:pointer;border-radius:12px;padding:12px 18px;font-weight:700;transition:all .15s;display:inline-block}
.btn-primary{background:var(--grad);color:#fff;border:0;box-shadow:0 8px 28px rgba(75,137,255,0.14)}
.btn-outline{background:transparent;border:2px solid var(--brand-1);color:var(--brand-1)}
.btn-link{background:transparent;border:0;color:var(--brand-2);font-weight:700}
.hero-subitems{margin-top:14px;display:flex;gap:12px;flex-wrap:wrap}
.sub-link{color:var(--muted);font-weight:600}

/* hero graphic */
.hero-right .hero-graphic{height:320px;border-radius:22px;background:var(--grad);box-shadow:0 18px 60px rgba(75,137,255,0.12)}

/* SECTIONS */
.section{max-width:var(--maxw);margin:60px auto;padding:40px 20px}
.section-title{font-size:30px;font-weight:800;color:var(--brand-2);text-align:center;margin:0}
.section-sub{text-align:center;color:var(--muted);margin-top:8px;margin-bottom:28px}

/* services grid (larger cards, stacked gradient) */
.services-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px;margin-top:20px}
.service-card{background:linear-gradient(180deg,#fff,#FAF5E9);border-radius:12px;padding:18px;border:1px solid rgba(10,10,10,0.03);box-shadow:0 8px 24px rgba(9,30,66,0.04);transition:all .18s}
.service-card h3{margin:0 0 8px;font-size:18px;color:var(--brand-2)}
.service-card .desc{color:var(--muted);line-height:1.45;margin-bottom:12px}
.apply-cta{display:inline-block;padding:8px 12px;border-radius:10px;background:var(--brand-1);color:#fff;font-weight:700}

/* tools area: three columns -> stacked on mobile */
.tools-wrap{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.card{background:var(--card);padding:18px;border-radius:12px;border:1px solid rgba(0,0,0,0.04);box-shadow:0 6px 18px rgba(0,0,0,0.03)}
.card.wide{grid-column:1/-1}
.registration-card label{display:block;font-size:13px;margin-top:10px}
.registration-card input{width:100%;padding:10px;border-radius:8px;border:1px solid #e8e8e8;margin-top:6px}
.form-actions{display:flex;gap:12px;align-items:center;margin-top:12px}
.form-status{font-size:13px;color:var(--muted)}

/* quick unlock vertical */
.quick-unlock-vertical input{width:100%;padding:10px;border-radius:8px;border:1px solid #e8e8e8;margin-top:8px}

/* resources */
.resources-grid{display:flex;gap:12px;flex-wrap:wrap;margin-top:12px}
.resource-pill{padding:10px 14px;border-radius:10px;background:linear-gradient(180deg,#fff,#FAF5E9);border:1px solid rgba(0,0,0,0.04);color:var(--brand-2);font-weight:700}

/* footer */
footer{background:#0f1724;color:#cbd5e1;padding:40px 20px;margin-top:40px}
.footer-inner{max-width:var(--maxw);margin:0 auto;display:flex;gap:36px;flex-wrap:wrap}
.footer-col{flex:1;min-width:160px}
.footer-col h4{color:#fff;margin:0 0 8px}
.footer-copy{text-align:center;color:#94a3b8;margin-top:20px;padding-top:10px;border-top:1px solid rgba(255,255,255,0.02)}

/* responsive */
@media(max-width:1024px){
  .hero{grid-template-columns:1fr 360px;padding:100px 20px 60px}
  .services-grid{grid-template-columns:1fr}
  .tools-wrap{grid-template-columns:1fr}
}
@media(max-width:720px){
  .menu{display:none}
  .hamburger{display:block}
  .hero{grid-template-columns:1fr;padding:110px 16px 40px}
  .brand-text{display:inline-block}
  .hero-title{font-size:28px}
  .hero-right{display:none}
  .services-grid{grid-template-columns:1fr}
  .footer-inner{flex-direction:column}
  .mobile-menu{display:block}
  .mobile-menu a{display:block;padding:10px 0;border-bottom:1px solid rgba(0,0,0,0.03)}
  .mobile-actions{padding:12px 0;display:flex;gap:12px;flex-direction:column}
}

/* small niceties */
.btn:active{transform:translateY(1px)}

/* Ensure mobile menu is hidden by default */
.mobile-menu[aria-hidden="true"] {
  display: none;
}

/* === 强制：移动端基于 aria-hidden 隐藏/显示移动菜单 === */
/* 放在 main.css 最底部，确保覆盖 media 查询 */
@media (max-width: 720px) {
  /* 默认收起（当 aria-hidden="true"） */
  .mobile-menu[aria-hidden="true"] {
    display: none !important;
    opacity: 0;
    transform: translateY(-6px);
    pointer-events: none;
  }

  /* 展开（当 aria-hidden="false"） */
  .mobile-menu[aria-hidden="false"] {
    display: block !important;
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
  }

  /* 让汉堡 open 状态更明显（可选美化） */
  .hamburger.open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
  .hamburger.open span:nth-child(2) { opacity: 0; }
  .hamburger.open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }
}