:root {
    --collection-primary: var(--theme-primary, #5754e8);
    --collection-strong: var(--theme-primary-strong, #403dbd);
    --collection-soft: var(--theme-soft, #eef0ff);
    --collection-ink: #172033;
    --collection-muted: #748096;
    --collection-border: #e4e9f1;
}

* { box-sizing: border-box; }
body { margin: 0; background: #f5f7fa; color: var(--collection-ink); font-family: "Microsoft YaHei", "PingFang SC", sans-serif; }
.collection-shell { min-height: 100vh; background: #f5f7fa; }
.collection-header { position: sticky; top: 42px; z-index: 999; border-top: 0; box-shadow: 0 4px 20px rgba(31, 45, 74, .07); }
.collection-header.header-adjusted { top: 0; }
.collection-header .header-actions { min-width: 120px; justify-content: flex-end; }
.collection-header .account-trigger { cursor: pointer; }
.collection-account { color: #344054; text-decoration: none; font-weight: 600; }
.collection-account:hover { color: var(--collection-primary); }
.collection-page { width: min(1200px, calc(100% - 48px)); margin: 24px auto 80px; }
.collection-toolbar { padding: 8px 0 18px; display: flex; align-items: center; justify-content: space-between; color: var(--collection-muted); }
.collection-toolbar strong { color: var(--collection-primary); font-size: 22px; }
.collection-search { width: 300px; height: 42px; display: flex; align-items: center; gap: 8px; padding: 0 14px; border: 1px solid var(--collection-border); border-radius: 12px; background: #fff; }
.collection-search:focus-within { border-color: var(--collection-primary); box-shadow: 0 0 0 3px color-mix(in srgb, var(--collection-primary) 12%, transparent); }
.collection-search input { width: 100%; border: 0; outline: 0; background: transparent; }
.collection-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 22px; }
.collection-card { overflow: hidden; min-width: 0; color: inherit; text-decoration: none; border: 1px solid var(--collection-border); border-radius: 16px; background: #fff; transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease; }
.collection-card:hover { transform: translateY(-5px); border-color: color-mix(in srgb, var(--collection-primary) 38%, white); box-shadow: 0 20px 40px rgba(31,45,74,.12); }
.collection-cover { aspect-ratio: 16 / 9; overflow: hidden; }
.collection-cover img, .detail-cover img { width: 100%; height: 100%; object-fit: cover; display: block; }
.generated-cover { position: relative; display: flex; flex-direction: column; justify-content: center; padding: 24px; overflow: hidden; color: #fff; background: linear-gradient(135deg, var(--collection-strong), var(--collection-primary)); }
.generated-cover::before { content: ""; position: absolute; inset: -45% -20%; background: repeating-radial-gradient(circle at 80% 30%, rgba(255,255,255,.16) 0 1px, transparent 2px 18px); transform: rotate(-9deg); }
.generated-cover > * { position: relative; z-index: 1; }
.generated-cover .cover-kicker { font-size: 11px; opacity: .74; letter-spacing: .08em; }
.generated-cover strong { margin-top: 12px; font-size: clamp(17px, 1.5vw, 23px); line-height: 1.4; }
.generated-cover .cover-line { width: 36px; height: 3px; margin-top: 18px; border-radius: 2px; background: #fff; }
.generated-cover i { position: absolute; right: 16px; bottom: 12px; font: 700 10px/1 sans-serif; opacity: .5; letter-spacing: .12em; }
.collection-card-body { padding: 18px; }
.collection-card-body h2 { min-height: 48px; margin: 0; font-size: 17px; line-height: 1.45; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.collection-card-body p { height: 38px; margin: 9px 0 18px; color: var(--collection-muted); font-size: 13px; line-height: 1.5; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.collection-card-meta { display: flex; align-items: center; justify-content: space-between; }
.collection-card-meta .member-free { color: var(--collection-primary); font-size: 13px; font-weight: 600; }
.collection-card-meta strong { color: var(--collection-primary); }
.collection-loading { min-height: 180px; display: grid; place-items: center; color: var(--collection-muted); }
.collection-empty { grid-column: 1 / -1; padding: 80px 24px; text-align: center; border: 1px dashed var(--collection-border); border-radius: 18px; background: #fff; color: var(--collection-muted); }
.collection-empty > span { width: 58px; height: 58px; display: grid; place-items: center; margin: 0 auto 16px; border-radius: 18px; background: var(--collection-soft); color: var(--collection-primary); font-size: 25px; }
.collection-empty h2 { margin: 0 0 8px; color: var(--collection-ink); }
.collection-empty p { margin: 0; }
.collection-empty.compact { padding: 38px 20px; }

.detail-page { margin-top: 22px; padding-bottom: 70px; }
.collection-breadcrumb { display: flex; gap: 10px; align-items: center; margin-bottom: 18px; color: #8b95a7; font-size: 14px; }
.collection-breadcrumb a { color: #7b879b; text-decoration: none; }
.collection-breadcrumb strong { color: #4a5568; }
.detail-hero { min-height: 200px; display: grid; grid-template-columns: 280px minmax(0, 1fr) 170px; gap: 28px; align-items: center; padding: 24px; border: 1px solid var(--collection-border); border-radius: 18px; background: #fff; box-shadow: 0 10px 35px rgba(31,45,74,.06); }
.detail-cover { aspect-ratio: 16/9; border-radius: 12px; }
.detail-title-row { display: flex; align-items: flex-start; gap: 12px; }
.detail-title-row h1 { margin: 0; font-size: 26px; line-height: 1.35; }
.detail-title-row span { flex: 0 0 auto; padding: 4px 8px; color: var(--collection-primary); background: var(--collection-soft); border: 1px solid color-mix(in srgb, var(--collection-primary) 28%, white); border-radius: 5px; font-size: 12px; }
.detail-copy > p { margin: 14px 0 26px; color: var(--collection-muted); line-height: 1.7; }
.detail-meta { display: flex; flex-wrap: wrap; gap: 18px; color: #8a94a6; font-size: 13px; }
.detail-meta strong { color: var(--collection-primary); font-weight: 500; }
.detail-price { align-self: stretch; display: flex; flex-direction: column; align-items: flex-end; justify-content: center; padding-left: 24px; border-left: 1px solid var(--collection-border); }
.detail-price span { color: #8a94a6; font-size: 13px; }
.detail-price strong { margin: 7px 0; color: var(--collection-primary); font-size: 29px; }
.detail-price em { color: var(--collection-primary); font-size: 12px; font-style: normal; }
.material-package { margin-top: 18px; overflow: hidden; border: 1px solid var(--collection-border); border-radius: 16px; background: #fff; }
.material-list-header { height: 58px; display: grid; grid-template-columns: 72px 1fr auto; align-items: center; padding: 0 24px; border-bottom: 1px solid var(--collection-border); }
.material-list-header label { display: flex; align-items: center; gap: 8px; }
.material-list-header > span { color: var(--collection-muted); font-size: 13px; }
.collection-material-row { min-height: 64px; display: grid; grid-template-columns: 34px 28px minmax(0, 1fr) 90px; gap: 8px; align-items: center; margin: 0 24px; border-bottom: 1px solid #edf0f4; }
.collection-material-row:last-child { border-bottom: 0; }
.material-check input { width: 17px; height: 17px; accent-color: var(--collection-primary); }
.material-file-icon { width: 22px; height: 25px; display: grid; place-items: center; color: #2877e5; border: 1px solid currentColor; border-radius: 3px; font: 700 11px sans-serif; }
.material-file-icon.ppt { color: #f06445; border: 0; border-radius: 0; }.material-file-icon.pdf { color: #e64b52; }.material-file-icon.excel { color: #16b96b; border: 0; border-radius: 0; }.material-file-icon.file { color: #7a879c; }
.material-row-copy { min-width: 0; }
.material-row-copy a { display: block; overflow: hidden; color: #263244; text-decoration: none; text-overflow: ellipsis; white-space: nowrap; }
.material-row-copy a:hover { color: var(--collection-primary); }
.material-row-copy small { display: block; margin-top: 4px; color: #9aa3b2; }
.material-preview { justify-self: end; color: var(--collection-primary); text-decoration: none; font-size: 14px; }
.collection-action-bar { position: fixed; z-index: 25; left: 0; right: 0; bottom: 0; min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 10px max(24px, calc((100vw - 1280px) / 2)); border-top: 1px solid var(--collection-border); background: rgba(255,255,255,.96); box-shadow: 0 -8px 28px rgba(31,45,74,.1); backdrop-filter: blur(10px); }
.collection-action-bar.hidden { display: none; }
.action-summary { display: flex; align-items: center; gap: 20px; color: #667085; }
.action-summary label { display: flex; gap: 7px; align-items: center; }
.action-summary input { accent-color: var(--collection-primary); }
.action-summary strong { color: var(--collection-primary); }
.action-buttons { display: flex; }
.action-buttons > * { min-width: 132px; height: 46px; display: inline-flex; align-items: center; justify-content: center; border: 0; color: #fff; text-decoration: none; font-weight: 700; cursor: pointer; }
.action-buy { border-radius: 8px 0 0 8px; background: var(--collection-primary); }
.action-member { background: #ff9d16; }
.action-download { border-radius: 0 8px 8px 0; background: #5d6877; }
.action-download:disabled { opacity: .45; cursor: not-allowed; }
.collection-toast { position: fixed; z-index: 80; right: 24px; bottom: 92px; max-width: min(420px, calc(100vw - 40px)); padding: 12px 18px; color: #fff; border-radius: 10px; background: #344054; box-shadow: 0 12px 34px rgba(15,23,42,.2); }
.collection-toast.success { background: #16936a; }.collection-toast.error { background: #d94a50; }.collection-toast.hidden { display: none; }

@media (max-width: 1050px) {
    .collection-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .detail-hero { grid-template-columns: 220px minmax(0, 1fr); }
    .detail-price { grid-column: 1 / -1; flex-direction: row; align-items: center; gap: 12px; padding: 16px 0 0; border-left: 0; border-top: 1px solid var(--collection-border); }
}
@media (max-width: 760px) {
    .collection-page { width: min(100% - 24px, 1200px); margin-top: 16px; }
    .collection-header .nav-menu { display: none; }
    .collection-toolbar { align-items: stretch; flex-direction: column; gap: 12px; }.collection-search { width: 100%; }
    .collection-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
    .detail-hero { grid-template-columns: 1fr; }.detail-cover { max-width: 420px; }.detail-title-row { flex-direction: column; }
    .collection-material-row { grid-template-columns: 30px 24px minmax(0,1fr) 58px; margin: 0 12px; }.material-row-copy small { display: none; }
    .material-list-header { padding: 0 12px; grid-template-columns: 66px 1fr auto; }
    .collection-action-bar { align-items: stretch; flex-direction: column; gap: 8px; padding: 10px 12px; }.action-summary { justify-content: space-between; }.action-buttons > * { flex: 1; min-width: 0; }
}
@media (max-width: 480px) {
    .collection-grid { grid-template-columns: 1fr; }
}