/* COGO30 官網（2026-10-14 重建，取代 OpenAI 網站平台版本） */
:root{--bg:#f6f1e9;--ink:#232826;--muted:#6b726e;--orange:#e8613c;--orange-dark:#c94e2c;--lime:#d7e488;--green:#194d3d;--card:#fffdf9;--line:#e6ddd0;--max:1080px}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.7 system-ui,-apple-system,"PingFang TC","Noto Sans TC","Microsoft JhengHei",sans-serif;-webkit-font-smoothing:antialiased}
a{color:inherit}
img{max-width:100%;display:block}
.wrap{max-width:var(--max);margin:0 auto;padding:0 20px}
/* 導覽 */
.nav{position:sticky;top:0;z-index:10;background:rgba(246,241,233,.92);backdrop-filter:saturate(1.4) blur(8px);border-bottom:1px solid transparent}
.nav.scrolled{border-color:var(--line)}
.nav .wrap{display:flex;align-items:center;justify-content:space-between;height:62px;gap:12px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font-weight:900;letter-spacing:.02em;font-size:19px}
.brand img{width:34px;height:34px;border-radius:50%}
.brand span b{color:var(--orange)}
.nav-links{display:flex;gap:6px;align-items:center}
.nav-links a{text-decoration:none;font-size:14px;font-weight:700;padding:8px 10px;border-radius:10px}
.nav-links a:hover,.nav-links a[aria-current=page]{background:#ece5d9}
.nav-links a.cta{background:var(--ink);color:#fff}
@media (max-width:640px){.nav-links a.hide-sm{display:none}}
/* 按鈕 */
.btn{display:inline-flex;align-items:center;gap:8px;border:0;border-radius:14px;padding:13px 18px;font:inherit;font-size:15px;font-weight:800;text-decoration:none;cursor:pointer;background:var(--orange);color:#fff;transition:transform .15s,background .15s}
.btn:hover{background:var(--orange-dark);transform:translateY(-1px)}
.btn.ghost{background:transparent;color:var(--ink);border:1.5px solid var(--line)}
.btn.ghost:hover{background:#fff}
.btn.green{background:var(--green)}
.btn.green:hover{background:#123b2e}
.btn.small{padding:9px 13px;font-size:14px;border-radius:11px}
/* 區塊 */
section{padding:64px 0}
.kicker{font-size:12px;letter-spacing:.16em;color:var(--orange);font-weight:800;text-transform:uppercase}
h1,h2,h3{line-height:1.3;margin:0}
h1{font-size:clamp(26px,6.8vw,54px);font-weight:900;margin:12px 0 18px}
h1 em,h2 em{font-style:normal;color:var(--orange)}
h2{font-size:clamp(25px,4vw,36px);font-weight:900;margin:10px 0 14px}
h3{font-size:18px;font-weight:800}
.lead{font-size:clamp(16px,2.2vw,19px);color:var(--muted);max-width:640px;margin:0 0 26px}
.muted{color:var(--muted)}
.small{font-size:14px}
.actions{display:flex;gap:10px;flex-wrap:wrap}
/* Hero */
.hero{position:relative;overflow:hidden;padding:72px 0 80px}
.hero:before{content:"";position:absolute;width:min(520px,80vw);height:min(520px,80vw);border-radius:50%;background:var(--lime);opacity:.6;right:-120px;top:-80px}
.hero .wrap{position:relative}
.hero-note{margin-top:22px;font-size:14px;color:var(--muted)}
/* 卡片與網格 */
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
@media (max-width:820px){.grid3{grid-template-columns:1fr}}
.card{background:var(--card);border:1px solid var(--line);border-radius:22px;padding:22px}
.card .no{width:34px;height:34px;border-radius:50%;background:var(--green);color:#fff;display:grid;place-items:center;font-weight:800;font-size:14px;margin-bottom:12px}
.card p{margin:8px 0 0;color:var(--muted);font-size:15px}
.band{background:#efe7da}
/* 試算 */
.calc-wrap{display:grid;grid-template-columns:1.05fr 1fr;gap:28px;align-items:center}
@media (max-width:820px){.calc-wrap{grid-template-columns:1fr}}
.calc{background:var(--green);color:#fff;border-radius:26px;padding:26px}
.calc .row{display:flex;justify-content:space-between;align-items:baseline;gap:10px;flex-wrap:wrap}
.calc label{display:block;margin:18px 0 6px;font-size:14px;opacity:.9}
.calc label b{color:var(--lime)}
.calc input[type=range]{width:100%;accent-color:var(--lime)}
.calc select{font:inherit;font-size:15px;border-radius:10px;border:0;padding:8px 10px;background:#fff;color:var(--ink)}
.calc .result{margin-top:22px;padding-top:18px;border-top:1px solid rgba(255,255,255,.2)}
.calc .big{font-size:clamp(34px,6vw,46px);font-weight:900;color:var(--lime);line-height:1.1}
.calc .formula{font-size:13px;opacity:.85;margin-top:8px}
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-top:18px}
.steps div{background:#fff;border:1px solid var(--line);border-radius:16px;padding:14px}
.steps b{display:block;font-size:15px}
.steps span{font-size:13px;color:var(--muted)}
@media (max-width:520px){.steps{grid-template-columns:1fr}}
/* 課程 */
.courses{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}
.course{background:var(--card);border:1px solid var(--line);border-radius:22px;overflow:hidden;display:flex;flex-direction:column}
.course .cover{aspect-ratio:16/9;background:linear-gradient(135deg,var(--lime),#f2c6b2);display:grid;place-items:center;font-weight:900;color:var(--green);font-size:20px;padding:12px;text-align:center}
.course .cover img{width:100%;height:100%;object-fit:cover}
.course .body{padding:16px 18px 18px;display:flex;flex-direction:column;gap:8px;flex:1}
.course .meta{font-size:13px;color:var(--muted)}
.course .summary{font-size:14px;color:var(--muted);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.pill{display:inline-block;align-self:flex-start;font-size:12px;font-weight:800;border-radius:999px;padding:3px 10px;background:#e5efe9;color:var(--green)}
.pill.invite{background:#f3e9da;color:#7a5a20}
.pill.preview{background:#ece5d9;color:var(--muted)}
.cohort{border-top:1px dashed var(--line);padding-top:10px;display:flex;justify-content:space-between;align-items:center;gap:10px;flex-wrap:wrap}
.cohort .info{font-size:13px}
.empty{border:1.5px dashed #cbbfae;border-radius:20px;padding:28px;color:var(--muted);text-align:center;background:rgba(255,255,255,.4)}
.filters{display:flex;gap:8px;flex-wrap:wrap;margin:0 0 18px}
.filters button{font:inherit;font-size:14px;font-weight:700;border:1.5px solid var(--line);background:#fff;border-radius:999px;padding:7px 14px;cursor:pointer}
.filters button[aria-pressed=true]{background:var(--ink);color:#fff;border-color:var(--ink)}
/* Host */
.rules{list-style:none;padding:0;margin:0;display:grid;gap:10px}
.rules li{background:#fff;border:1px solid var(--line);border-radius:14px;padding:12px 14px;font-size:15px}
.rules li:before{content:"✓";color:var(--green);font-weight:900;margin-right:8px}
.flow{counter-reset:f;display:grid;grid-template-columns:repeat(4,1fr);gap:10px}
.flow div{background:#fff;border:1px solid var(--line);border-radius:16px;padding:14px;counter-increment:f;font-weight:700;font-size:15px}
.flow div:before{content:counter(f);display:block;color:var(--orange);font-size:22px;font-weight:900}
@media (max-width:720px){.flow{grid-template-columns:1fr 1fr}}
/* 頁尾 */
footer{background:var(--ink);color:#d8d2c8;padding:42px 0;font-size:14px}
footer .wrap{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}
footer a{color:#fff;text-decoration:none;margin-right:14px}
footer .tag{opacity:.7;margin-top:6px}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}