:root{--ink:#26324b;--muted:#6e7890;--coral:#f26e5b;--yellow:#ffd55d;--paper:#fff;--cream:#fffaf0;--line:#e9e4da;--shadow:0 18px 55px rgba(58,43,27,.11)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:#fbf8f1;font-family:"PingFang SC","Microsoft YaHei",system-ui,sans-serif}a{color:inherit;text-decoration:none}.portal-header{height:78px;max-width:1320px;margin:auto;padding:0 28px;display:flex;align-items:center;justify-content:space-between}.portal-brand{display:flex;align-items:center;gap:12px}.portal-brand>span{width:46px;height:46px;border-radius:14px;display:grid;place-items:center;background:var(--coral);color:#fff;font:800 28px Georgia;box-shadow:0 5px 0 #cf5444;transform:rotate(-5deg)}.portal-brand b,.portal-brand small{display:block}.portal-brand small{margin-top:3px;color:var(--muted);font-size:11px}.portal-header nav{display:flex;gap:28px;align-items:center;font-size:13px;font-weight:700}.portal-header nav a:hover{color:var(--coral)}.edition{padding:8px 13px;border-radius:99px;background:#fff0e7;color:#d75746}.portal-hero{max-width:1260px;min-height:540px;margin:20px auto 70px;border-radius:38px;display:grid;grid-template-columns:1fr 1fr;overflow:hidden;background:linear-gradient(135deg,#fff0de,#ffe9e2);box-shadow:var(--shadow)}.hero-copy{padding:75px 65px;z-index:2}.tag{display:inline-block;padding:8px 13px;border-radius:99px;background:white;color:#d95a49;font-size:12px;font-weight:800}.hero-copy h1{font-size:clamp(42px,5vw,68px);line-height:1.13;margin:20px 0}.hero-copy h1 em{font-style:normal;color:var(--coral)}.hero-copy p{max-width:530px;line-height:1.9;color:#6d6260}.start-link{display:inline-flex;gap:18px;align-items:center;margin-top:16px;background:var(--coral);color:white;padding:16px 22px;border-radius:15px;font-weight:900;box-shadow:0 7px 0 #cf5444;transition:.2s}.start-link:hover{transform:translateY(-3px)}.hero-trust{display:flex;gap:15px;margin-top:35px;font-size:11px;color:#796e6a}.math-world{position:relative;overflow:hidden;background:linear-gradient(#bfeaff,#d9f2ff 62%,#b4d981 62%)}.planet{position:absolute;width:290px;height:205px;left:50%;top:48%;transform:translate(-50%,-35%);border-radius:50%;background:#69bd73;box-shadow:inset -28px -20px rgba(32,126,65,.18),0 24px 0 #4d9e62,0 35px 40px rgba(30,96,65,.25)}.planet:before{content:"";position:absolute;width:90px;height:45px;left:35px;top:18px;border-radius:50%;background:#ffe09b;transform:rotate(-12deg)}.planet-face{font-size:34px;position:absolute;left:112px;top:82px}.flag{position:absolute;right:40px;top:-38px;padding:8px 13px;background:#ffd45b;border:4px solid #775638;border-radius:8px;font-weight:900;transform:rotate(5deg)}.orbit{position:absolute;border:2px dashed rgba(61,103,149,.28);border-radius:50%;inset:70px 40px}.orbit-b{inset:125px 80px;transform:rotate(22deg)}.orbit span{position:absolute;width:42px;height:42px;border-radius:50%;display:grid;place-items:center;background:#5b8def;color:white;font-size:23px;left:40px;top:15px}.orbit-b span{left:auto;right:30px;top:auto;bottom:0;background:#8c72df}.float-card{position:absolute;background:white;border-radius:18px;padding:14px 20px;text-align:center;box-shadow:var(--shadow);font-weight:800;animation:float 3s ease-in-out infinite}.card-a{left:7%;top:17%;transform:rotate(-6deg)}.card-b{right:8%;top:21%;animation-delay:.5s}.card-c{right:10%;bottom:14%;font-size:20px;animation-delay:1s}.rocket{position:absolute;font-size:48px;left:8%;bottom:17%;transform:rotate(-25deg)}.star{position:absolute;color:#fff;font-size:22px}.s1{right:20%;top:9%}.s2{left:18%;top:9%}.s3{right:7%;top:49%}@keyframes float{50%{transform:translateY(-9px) rotate(2deg)}}.books-section,.method-section{max-width:1260px;margin:0 auto 90px;padding:0 20px}.section-title{display:flex;justify-content:space-between;align-items:end;margin-bottom:25px}.section-title span{font-size:11px;letter-spacing:.14em;color:var(--coral);font-weight:900}.section-title h2{font-size:32px;margin:7px 0 0}.section-title p{color:var(--muted);font-size:13px}.book-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:17px}.book-card{min-height:260px;padding:23px;border-radius:25px;background:#fff;border:1px solid var(--line);display:flex;flex-direction:column;transition:.25s;position:relative;overflow:hidden}.book-card:after{content:"";position:absolute;width:120px;height:120px;border-radius:50%;right:-45px;bottom:-55px;background:var(--accent,#eee);opacity:.15}.book-card.ready{--accent:#f26e5b;border:2px solid #f4ac9e;background:linear-gradient(145deg,#fff,#fff1eb);box-shadow:0 12px 35px rgba(221,91,72,.12)}.book-card.ready:hover{transform:translateY(-6px);box-shadow:var(--shadow)}.book-top{display:flex;justify-content:space-between}.book-status{padding:6px 9px;background:#f1efea;border-radius:99px;font-size:10px;color:#888}.ready .book-status{background:var(--coral);color:white}.book-icon{font-size:38px}.book-card>small{color:var(--muted);margin-top:22px}.book-card h3{font-size:27px;margin:6px 0}.book-card h3 em{font-size:14px;font-style:normal;color:var(--coral)}.book-card p{color:var(--muted);font-size:12px}.book-bottom{margin-top:auto;border-top:1px solid var(--line);padding-top:14px;display:flex;justify-content:space-between}.ready .book-bottom{color:var(--coral)}.soon{filter:saturate(.6)}.grade4{--accent:#5b8def}.grade5{--accent:#55b895}.grade6{--accent:#8b72df}.section-title.center{justify-content:center;text-align:center}.method-section{background:#26324b;color:white;border-radius:32px;padding:52px}.method-line{display:grid;grid-template-columns:1fr 30px 1fr 30px 1fr 30px 1fr 30px 1fr;align-items:center;text-align:center;margin-top:34px}.method-line article{background:rgba(255,255,255,.06);padding:24px 10px;border-radius:20px}.method-line i{font-size:36px;font-style:normal;display:block}.method-line b{display:block;margin-top:10px}.method-line p{font-size:11px;color:#aeb7cb}.method-line>span{color:#ffd45b;font-size:22px}footer{border-top:1px solid var(--line);padding:28px;display:flex;justify-content:center;gap:20px;color:var(--muted);font-size:12px}footer b{color:var(--ink)}
@media(max-width:1000px){.portal-hero{margin:15px 20px 60px}.book-grid{grid-template-columns:repeat(2,1fr)}.hero-copy{padding:55px 38px}.method-line{grid-template-columns:1fr 1fr 1fr;gap:12px}.method-line>span{display:none}.method-line article:nth-of-type(4),.method-line article:nth-of-type(5){grid-column:auto}}
@media(max-width:700px){.portal-header{height:66px;padding:0 18px}.portal-header nav a{display:none}.portal-header nav{gap:8px}.portal-brand small{display:none}.portal-hero{grid-template-columns:1fr;margin:8px 12px 48px;border-radius:28px}.hero-copy{padding:42px 25px}.hero-copy h1{font-size:40px}.hero-trust{gap:8px;flex-wrap:wrap}.math-world{min-height:350px}.section-title{display:block}.section-title p{line-height:1.6}.book-grid{grid-template-columns:1fr}.books-section,.method-section{margin-bottom:55px}.method-section{margin-left:12px;margin-right:12px;padding:35px 18px}.method-line{grid-template-columns:1fr 1fr}.method-line article:last-child{grid-column:1/-1}footer{flex-direction:column;text-align:center;gap:5px}}