/* =========================================================
   試聽專區 v2 — trial-v2.css（iv2 設計系統，scope: .iv2-root）
   風格：學院編輯風（Academic Editorial）— 紙白×學院深藍×金榜金
   CMS 驅動：依科目分組、篩選器、lightbox 播放 Bunny / YouTube
   規則：iv2- 前綴 scope、內文 Noto Sans TC、標題 Noto Serif TC、全形標點、cache-bust
   ========================================================= */

.iv2-root{
  --paper:#f4f1ea;
  --ink:#16223f;
  --ink-soft:#3c4866;
  --muted:#7b819a;
  --line:#ddd6c8;
  --line-2:#e7e1d5;
  --primary:#2f3f86;
  --primary-deep:#222e63;
  --gold:#bf9b48;
  --gold-deep:#9c7c2f;
  --card:#fffdf8;
  --shadow-sm:0 1px 2px rgba(22,34,63,.05);
  --shadow-md:0 14px 34px -18px rgba(22,34,63,.35);
  --shadow-lg:0 40px 80px -36px rgba(22,34,63,.5);
  --serif:"Noto Serif TC",serif;
  --fraunces:"Fraunces",serif;
  --sans:"Noto Sans TC","Noto Sans Traditional Chinese",sans-serif;
  --r:14px;
  --ease:cubic-bezier(.2,.7,.2,1);

  position:relative;
  font-family:var(--sans);
  color:var(--ink);
  background-color:var(--paper);
  background-image:
    radial-gradient(120% 70% at 85% -8%, rgba(47,63,134,.08), transparent 60%),
    radial-gradient(80% 50% at 0% 0%, rgba(191,155,72,.08), transparent 55%),
    linear-gradient(rgba(22,34,63,.035) 1px,transparent 1px),
    linear-gradient(90deg,rgba(22,34,63,.035) 1px,transparent 1px);
  background-size:auto,auto,48px 48px,48px 48px;
  line-height:1.6;
}
.iv2-root *{box-sizing:border-box}
.iv2-root a{color:inherit;text-decoration:none}

/* 容器 — 寬度對齊首頁(index-v2.css)：80% / 無上限 / 內距 24px；保留 hero 堆疊所需的 position+z-index */
.iv2-root .iv2-wrap{width:80%;max-width:none;margin-inline:auto;padding-inline:24px;position:relative;z-index:1}
@media (max-width:1024px){.iv2-root .iv2-wrap{width:90%}}
@media (max-width:600px){.iv2-root .iv2-wrap{width:100%;padding-inline:14px}}

/* 共用排版 */
.iv2-root .iv2-h1{font-family:var(--serif);font-weight:900;color:var(--ink);font-size:clamp(40px,5.4vw,78px);line-height:1.04;letter-spacing:.01em;margin:0}
.iv2-root .iv2-lead{font-size:clamp(16px,1.4vw,18px);line-height:1.8;color:var(--ink-soft)}

/* 麵包屑 */
.iv2-root .iv2-page-utility-row{border-bottom:1px solid var(--line)}
.iv2-root .iv2-page-utility{padding-block:16px}
.iv2-root .iv2-crumb{font-size:13px;color:var(--muted);letter-spacing:.02em}
.iv2-root .iv2-crumb a:hover{color:var(--primary)}
.iv2-root .iv2-crumb .sep{margin:0 8px;opacity:.6}

/* ===== HERO ===== */
/* z-index:auto 蓋掉全站 css/style.css 的 header{z-index:999999}；
   否則此 <header> 會以 999999 疊在固定導覽列(.iv2-nav z:1000)之上，蓋住整排選單點擊 */
.iv2-root .iv2-trial-hero{position:relative;z-index:auto;padding-block:42px 50px}
.iv2-root .iv2-hero-eyebrow{font-family:var(--fraunces);font-style:italic;font-size:15px;letter-spacing:.04em;color:var(--gold-deep);display:inline-flex;align-items:center;gap:12px;margin-bottom:18px}
.iv2-root .iv2-hero-eyebrow::before{content:"";width:42px;height:1px;background:var(--gold)}
.iv2-root .iv2-trial-hero .iv2-accent{position:relative;white-space:nowrap}
.iv2-root .iv2-trial-hero .iv2-accent::after{content:"";position:absolute;left:-2%;right:-2%;bottom:.12em;height:.34em;z-index:-1;background:linear-gradient(90deg,rgba(191,155,72,.55),rgba(191,155,72,.2));border-radius:3px}
.iv2-root .iv2-trial-hero .iv2-lead{margin-top:22px;max-width:560px}
.iv2-root .iv2-hero-stats{display:flex;gap:38px;margin-top:32px;flex-wrap:wrap}
.iv2-root .iv2-stat .n{font-family:var(--fraunces);font-size:32px;font-weight:600;color:var(--primary);line-height:1}
.iv2-root .iv2-stat .l{font-size:13px;color:var(--muted);margin-top:6px;letter-spacing:.06em}
.iv2-root .iv2-hero-mark{position:absolute;right:0;top:8px;font-family:var(--serif);font-weight:900;font-size:clamp(130px,20vw,280px);line-height:.8;color:var(--ink);opacity:.04;pointer-events:none;user-select:none;z-index:0}
@media(max-width:760px){.iv2-root .iv2-hero-mark{display:none}}

/* ===== 篩選工具列 ===== */
.iv2-root .iv2-trial-filter{position:sticky;top:0;z-index:30;display:flex;gap:14px;align-items:center;flex-wrap:wrap;background:rgba(244,241,234,.85);backdrop-filter:blur(10px);border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding-block:16px;margin-bottom:8px}
.iv2-root .iv2-filter-search{position:relative;flex:1 1 260px;min-width:200px}
.iv2-root .iv2-filter-search svg{position:absolute;left:14px;top:50%;transform:translateY(-50%);width:18px;height:18px;color:var(--muted)}
.iv2-root .iv2-filter-search input{width:100%;height:46px;border:1px solid var(--line);border-radius:999px;background:var(--card);padding:0 18px 0 42px;font-family:var(--sans);font-size:15px;color:var(--ink);transition:border-color .2s,box-shadow .2s}
.iv2-root .iv2-filter-search input::placeholder{color:var(--muted)}
.iv2-root .iv2-filter-search input:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 4px rgba(47,63,134,.1)}
.iv2-root .iv2-filter-select{position:relative;height:46px;min-width:148px;border:1px solid var(--line);border-radius:999px;background:var(--card) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%233c4866' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E") no-repeat right 16px center;padding:0 38px 0 18px;font-family:var(--sans);font-size:14.5px;color:var(--ink);cursor:pointer;-webkit-appearance:none;appearance:none;transition:border-color .2s,color .2s}
.iv2-root .iv2-filter-select:focus{outline:none;border-color:var(--primary)}
.iv2-root .iv2-filter-select.on{border-color:var(--primary);color:var(--primary);font-weight:700}
.iv2-root .iv2-filter-reset{height:46px;padding:0 20px;border:1px dashed var(--line);background:transparent;border-radius:999px;font-family:var(--sans);font-size:14px;color:var(--muted);cursor:pointer;transition:.2s}
.iv2-root .iv2-filter-reset:hover{color:var(--gold-deep);border-color:var(--gold)}
.iv2-root .iv2-filter-count{margin-left:auto;font-size:13.5px;color:var(--muted)}
.iv2-root .iv2-filter-count b{font-family:var(--fraunces);color:var(--primary);font-size:17px;font-weight:600}
@media(max-width:760px){.iv2-root .iv2-filter-count{margin-left:0;width:100%}.iv2-root .iv2-filter-select{flex:1 1 40%;min-width:0}}

/* ===== 狀態 ===== */
.iv2-root .iv2-trial-state{text-align:center;color:var(--muted);padding-block:72px;font-size:1.05em}

/* ===== 科目分區 ===== */
.iv2-root .iv2-trial-list-section{padding-block:24px 90px}
.iv2-root .iv2-subject-group{padding-top:46px;opacity:0;transform:translateY(22px);transition:opacity .7s var(--ease),transform .7s var(--ease)}
.iv2-root .iv2-subject-group.in{opacity:1;transform:none}
.iv2-root .iv2-subject-head{display:flex;align-items:flex-end;gap:16px;padding-bottom:22px;border-bottom:1px solid var(--line);margin-bottom:28px}
.iv2-root .iv2-subject-idx{font-family:var(--fraunces);font-size:18px;font-weight:600;color:var(--gold-deep);letter-spacing:.05em;line-height:1.2;padding-top:6px}
.iv2-root .iv2-subject-name{font-family:var(--serif);font-weight:700;font-size:clamp(24px,3.2vw,36px);color:var(--ink);line-height:1.1}
.iv2-root .iv2-subject-meta{margin-left:auto;font-size:13px;color:var(--muted);letter-spacing:.04em;white-space:nowrap;padding-bottom:6px}

/* ===== 影片網格 / 卡片 ===== */
.iv2-root .iv2-trial-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:26px}
@media(max-width:900px){.iv2-root .iv2-trial-grid{grid-template-columns:repeat(2,1fr);gap:20px}}
@media(max-width:560px){.iv2-root .iv2-trial-grid{grid-template-columns:1fr}}

.iv2-root .iv2-trial-card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);overflow:hidden;cursor:pointer;box-shadow:var(--shadow-sm);transition:transform .35s var(--ease),box-shadow .35s var(--ease),border-color .35s var(--ease);display:flex;flex-direction:column}
.iv2-root .iv2-trial-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);border-color:var(--gold)}

.iv2-root .iv2-trial-thumb{position:relative;aspect-ratio:16/9;overflow:hidden;background:var(--ink)}
.iv2-root .iv2-thumb-grad{position:absolute;inset:0;background-size:cover;background-position:center;transition:transform .5s var(--ease)}
.iv2-root .iv2-trial-card:hover .iv2-thumb-grad{transform:scale(1.05)}
/* 無縮圖時的預設視覺：工程藍圖網格 + 同心圓線稿 */
.iv2-root .iv2-trial-thumb:not(.is-img) .iv2-thumb-grad::before{content:"";position:absolute;inset:0;opacity:.6;background-image:repeating-linear-gradient(0deg,rgba(255,255,255,.07) 0 1px,transparent 1px 28px),repeating-linear-gradient(90deg,rgba(255,255,255,.07) 0 1px,transparent 1px 28px);-webkit-mask-image:linear-gradient(125deg,#000,transparent 72%);mask-image:linear-gradient(125deg,#000,transparent 72%)}
.iv2-root .iv2-trial-thumb:not(.is-img) .iv2-thumb-grad::after{content:"";position:absolute;right:-46px;bottom:-58px;width:188px;height:188px;border-radius:50%;border:1.5px solid rgba(255,255,255,.18);box-shadow:0 0 0 20px rgba(255,255,255,.05),0 0 0 44px rgba(255,255,255,.03);transition:transform .6s var(--ease)}
.iv2-root .iv2-trial-card:hover .iv2-trial-thumb:not(.is-img) .iv2-thumb-grad::after{transform:scale(1.12) rotate(8deg)}
.iv2-root .iv2-thumb-sheen{position:absolute;inset:0;background:linear-gradient(120deg,rgba(255,255,255,.14),transparent 42%);pointer-events:none}

.iv2-root .iv2-play-overlay{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(16,22,40,.18);transition:background .35s var(--ease)}
.iv2-root .iv2-trial-card:hover .iv2-play-overlay{background:rgba(16,22,40,.34)}
.iv2-root .iv2-play-overlay span{width:64px;height:64px;border-radius:50%;display:flex;align-items:center;justify-content:center;background:rgba(255,253,248,.16);border:1.5px solid rgba(255,255,255,.6);backdrop-filter:blur(4px);transition:transform .35s var(--ease),background .35s var(--ease),border-color .35s var(--ease)}
.iv2-root .iv2-trial-card:hover .iv2-play-overlay span{transform:scale(1.12);background:var(--gold);border-color:var(--gold)}
.iv2-root .iv2-play-overlay svg{width:24px;height:24px;color:#fff;margin-left:3px}
.iv2-root .iv2-trial-card:hover .iv2-play-overlay svg{color:var(--ink)}

.iv2-root .iv2-trial-info{padding:18px 20px 20px;display:flex;flex-direction:column;gap:12px;flex:1}
.iv2-root .iv2-trial-name{font-family:var(--serif);font-weight:600;font-size:17px;line-height:1.45;color:var(--ink);margin:0;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.iv2-root .iv2-trial-tags{display:flex;flex-wrap:wrap;gap:7px;margin-top:auto}
.iv2-root .iv2-tag{font-size:11.5px;font-weight:500;letter-spacing:.03em;padding:4px 10px;border-radius:999px;line-height:1}
.iv2-root .iv2-tag.subj{background:rgba(47,63,134,.09);color:var(--primary)}
.iv2-root .iv2-tag.cls{background:rgba(191,155,72,.14);color:var(--gold-deep)}
.iv2-root .iv2-tag.exam{background:#eef0ea;color:var(--ink-soft)}

/* ===== Lightbox ===== */
.iv2-root .iv2-lightbox-mask{position:fixed;inset:0;z-index:80;display:none;align-items:center;justify-content:center;padding:26px;background:rgba(12,16,30,.9)}
.iv2-root .iv2-lightbox-mask.is-open{display:flex}
.iv2-root .iv2-lightbox-frame{position:relative;width:min(980px,100%)}
.iv2-root .iv2-lightbox-embed{position:relative;aspect-ratio:16/9;background:#000;border-radius:12px;overflow:hidden;box-shadow:var(--shadow-lg)}
.iv2-root .iv2-lightbox-embed iframe{position:absolute;inset:0;width:100%;height:100%;border:0}
.iv2-root .iv2-lightbox-close{position:absolute;top:-46px;right:0;width:40px;height:40px;border:0;border-radius:50%;background:rgba(255,255,255,.14);color:#fff;font-size:24px;cursor:pointer;transition:.2s}
.iv2-root .iv2-lightbox-close:hover{background:var(--gold);color:var(--ink)}
@media(max-width:600px){.iv2-root .iv2-lightbox-mask{padding:12px}.iv2-root .iv2-lightbox-close{top:-42px}}

@media(prefers-reduced-motion:reduce){
  .iv2-root *{animation:none!important;transition:none!important}
  .iv2-root .iv2-subject-group{opacity:1;transform:none}
}