:root { color: #20324a; background: #f5f8fc; font-family: "PingFang SC", "Microsoft YaHei", sans-serif; }
* { box-sizing: border-box; }
body { min-width: 320px; margin: 0; }
.series-home { min-height: 100vh; background: radial-gradient(circle at 50% -20%, #ddebff, transparent 42%), #f7f9fd; }
.series-shell { width: min(1160px, calc(100% - 48px)); margin: 0 auto; padding: 96px 0; }
.series-hero { max-width: 680px; margin: 0 auto 54px; text-align: center; }
.series-kicker { margin: 0 0 12px; color: #52719d; font-size: 14px; font-weight: 700; letter-spacing: .12em; }
.series-hero h1 { margin: 0; color: #1b2f4b; font-size: clamp(32px, 5vw, 48px); letter-spacing: -.04em; }
.series-hero > p:last-child { margin: 18px 0 0; color: #63738a; font-size: 17px; line-height: 1.7; }
.series-cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 22px; }
.series-card, .course-card { display: block; border: 1px solid #dde5f1; border-radius: 22px; background: #fff; box-shadow: 0 14px 28px #244c7810; text-decoration: none; transition: transform .18s ease, box-shadow .18s ease; }
.series-card { min-height: 278px; padding: 28px; color: #2e405b; }
.series-card:hover, .series-card:focus-visible { transform: translateY(-5px); box-shadow: 0 18px 36px #244c7820; outline: none; }
.series-code { display: grid; width: 42px; height: 42px; place-items: center; border-radius: 13px; background: #e9f1ff; color: #3768a5; font-size: 20px; font-weight: 800; }
.series-card-e .series-code { background: #e6f7f0; color: #298162; }
.series-card-f .series-code { background: #f1ecff; color: #7655aa; }
.series-card h2 { margin: 22px 0 5px; color: #20324a; font-size: 25px; }
.series-card p { margin: 9px 0; color: #6b7a8e; line-height: 1.55; }
.series-card .series-age { color: #3d5d84; font-weight: 700; }
.series-enter { display: flex; align-items: center; gap: 8px; margin-top: 26px; color: #356ba8; font-size: 14px; font-weight: 700; }
.series-enter b { font-size: 18px; }
.series-course-shell { max-width: 900px; }
.back-home { display: inline-block; margin-bottom: 56px; color: #54739a; font-size: 14px; font-weight: 700; text-decoration: none; }
.series-course-hero { margin-bottom: 38px; }
.course-heading { margin: 0 0 16px; font-size: 20px; }
.course-cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; color: #6b7a8e; }
.course-card { padding: 22px; }
.course-card p { margin: 0; color: #6c89aa; font-size: 13px; font-weight: 700; }
.course-card h3 { margin: 10px 0 18px; color: #29435f; font-size: 19px; line-height: 1.45; }
.course-card span { color: #55728f; font-size: 13px; }
.series-loading { grid-column: 1 / -1; color: #6b7a8e; text-align: center; }
@media (max-width: 760px) { .series-shell { width: min(100% - 32px, 520px); padding: 54px 0; } .series-hero { margin-bottom: 34px; } .series-cards, .course-cards { grid-template-columns: 1fr; } .series-card { min-height: 0; } }