/* 数位视界 · 立知 —— 门户样式（登录页、选科页、课件内的返回按钮） */
:root {
    --bg0: #04060d;
    --bg1: #0a1124;
    --glass: rgba(13, 20, 42, 0.62);
    --glass-strong: rgba(11, 17, 36, 0.86);
    --line: rgba(150, 180, 255, 0.14);
    --line-strong: rgba(150, 190, 255, 0.3);
    --text: #eaf0ff;
    --muted: #9aa8cc;
    --dim: #66739a;
    --accent: #4cd7ff;
    --accent-2: #9b8cff;
    --amber: #ffbf5a;
    --rose: #ff6f8e;
    --mint: #4fe3a6;
    --radius: 16px;
    --shadow: 0 18px 50px rgba(0, 0, 0, 0.5), inset 0 1px 0 rgba(255, 255, 255, 0.06);
    --font: "HarmonyOS Sans SC", "MiSans", "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", system-ui, sans-serif;
    --font-num: "Segoe UI Variable Display", "Segoe UI", Inter, "Helvetica Neue", Arial, sans-serif;
    --ease: cubic-bezier(.2, .8, .2, 1);
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html, body { min-height: 100%; }
body {
    font-family: var(--font); color: var(--text); -webkit-font-smoothing: antialiased;
    background: radial-gradient(ellipse 90% 70% at 70% 20%, #122047 0%, var(--bg1) 45%, var(--bg0) 100%) fixed;
}
button, input { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
#bg { position: fixed; inset: 0; z-index: 0; pointer-events: none; }
.vignette { position: fixed; inset: 0; z-index: 0; pointer-events: none; background: radial-gradient(ellipse 80% 75% at 50% 45%, transparent 55%, rgba(0, 0, 0, .6) 100%); }
.glass {
    background: var(--glass);
    backdrop-filter: blur(20px) saturate(150%); -webkit-backdrop-filter: blur(20px) saturate(150%);
    border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow);
}
@keyframes rise { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }
.enter { animation: rise .8s var(--ease) both; }
.enter-2 { animation: rise .8s .1s var(--ease) both; }
.enter-3 { animation: rise .8s .2s var(--ease) both; }

/* —— 品牌 —— */
.logo { display: flex; align-items: center; gap: 12px; font-weight: 700; letter-spacing: 2px; }
.logo svg { width: 34px; height: 34px; filter: drop-shadow(0 0 10px rgba(76, 215, 255, .5)); }
.logo b { font-size: 17px; }
.logo b i { font-style: normal; color: var(--accent); margin: 0 4px; }
.logo small { display: block; font-size: 11px; font-weight: 400; letter-spacing: 3px; color: var(--dim); }

/* —— 登录页 —— */
.login-wrap {
    position: relative; z-index: 2; min-height: 100vh;
    display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(360px, 440px); align-items: center;
    gap: 6vw; padding: 6vh 8vw;
}
.login-intro .eyebrow { font-family: var(--font-num); font-size: 12px; letter-spacing: 6px; color: var(--accent); margin: 44px 0 18px; }
.login-intro h1 { font-size: clamp(40px, 5.2vw, 72px); line-height: 1.12; font-weight: 800; letter-spacing: 4px; }
.login-intro h1 em {
    font-style: normal; background: linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 55%, var(--rose) 100%);
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.login-intro p { margin-top: 22px; max-width: 520px; font-size: 15px; line-height: 1.9; color: var(--muted); }
.login-intro .chips { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 30px; }
.login-intro .chips span {
    padding: 6px 14px; border-radius: 99px; font-size: 13px; color: var(--text);
    border: 1px solid var(--line-strong); background: rgba(255, 255, 255, .03);
}
.login-intro .chips span i { display: inline-block; width: 7px; height: 7px; border-radius: 50%; margin-right: 8px; vertical-align: 1px; box-shadow: 0 0 8px currentColor; }

.login-card { padding: 34px 34px 28px; }
.login-card h2 { font-size: 22px; letter-spacing: 2px; }
.login-card .sub { margin-top: 6px; font-size: 13px; color: var(--dim); }
.tabs { position: relative; display: grid; grid-template-columns: 1fr 1fr; margin: 24px 0 22px; padding: 4px; border-radius: 12px; background: rgba(0, 0, 0, .28); border: 1px solid var(--line); }
.tabs button { position: relative; z-index: 1; height: 38px; border-radius: 9px; font-size: 14px; color: var(--muted); transition: color .3s; }
.tabs button.on { color: var(--text); }
.tabs .pill { position: absolute; top: 4px; bottom: 4px; left: 4px; width: calc(50% - 4px); border-radius: 9px; background: linear-gradient(135deg, rgba(76, 215, 255, .22), rgba(155, 140, 255, .22)); border: 1px solid var(--line-strong); transition: transform .35s var(--ease); }
.tabs.staff .pill { transform: translateX(100%); }
.field { position: relative; margin-bottom: 16px; }
.field label { display: block; font-size: 12px; color: var(--muted); margin-bottom: 8px; letter-spacing: 1px; }
.field input {
    width: 100%; height: 46px; padding: 0 44px 0 14px; border-radius: 11px; outline: none;
    background: rgba(4, 8, 20, .55); border: 1px solid var(--line-strong); font-size: 15px;
    transition: border-color .2s, box-shadow .2s;
}
.field input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(76, 215, 255, .15); }
.field .eye { position: absolute; right: 6px; bottom: 6px; width: 34px; height: 34px; border-radius: 8px; color: var(--dim); display: grid; place-items: center; }
.field .eye:hover { color: var(--text); background: rgba(255, 255, 255, .06); }
.field .eye svg { width: 18px; height: 18px; }
.btn-primary {
    position: relative; width: 100%; height: 48px; margin-top: 8px; border-radius: 12px; font-size: 16px; font-weight: 700; letter-spacing: 6px;
    color: #041018; background: linear-gradient(100deg, #4cd7ff, #8fb8ff 55%, #b3a6ff);
    box-shadow: 0 10px 30px rgba(76, 215, 255, .28); transition: transform .2s, box-shadow .2s, opacity .2s;
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 14px 36px rgba(76, 215, 255, .4); }
.btn-primary:disabled { opacity: .6; pointer-events: none; }
.msg { min-height: 22px; margin-top: 14px; font-size: 13px; color: var(--rose); text-align: center; }
.msg.ok { color: var(--mint); }
.foot { margin-top: 14px; padding-top: 16px; border-top: 1px solid var(--line); font-size: 12px; line-height: 1.8; color: var(--dim); text-align: center; }
.copyright { position: fixed; z-index: 2; left: 0; right: 0; bottom: 16px; text-align: center; font-size: 12px; color: var(--dim); letter-spacing: 1px; }

/* —— 选科页 —— */
.home-top { position: relative; z-index: 3; display: flex; align-items: center; gap: 18px; padding: 22px 5vw; }
.home-top .grow { flex: 1; }
.user { display: flex; align-items: center; gap: 10px; padding: 6px 8px 6px 14px; border-radius: 99px; font-size: 13px; color: var(--muted); }
.user b { color: var(--text); font-weight: 500; }
.user .avatar { width: 28px; height: 28px; border-radius: 50%; display: grid; place-items: center; font-size: 13px; font-weight: 700; color: #041018; background: linear-gradient(135deg, var(--accent), var(--accent-2)); }
.user button { padding: 5px 12px; border-radius: 99px; font-size: 12px; color: var(--muted); border: 1px solid var(--line); }
.user button:hover { color: var(--text); border-color: var(--line-strong); }

.home { position: relative; z-index: 2; padding: 3vh 5vw 8vh; }
.home-head .eyebrow { font-family: var(--font-num); font-size: 12px; letter-spacing: 6px; color: var(--accent); }
.home-head h1 { margin-top: 14px; font-size: clamp(32px, 3.6vw, 50px); font-weight: 800; letter-spacing: 3px; }
.home-head p { margin-top: 12px; font-size: 15px; color: var(--muted); }
.subjects { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 22px; margin-top: 44px; perspective: 1200px; }
@media (max-width: 1100px) { .subjects { grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); } }
.subj {
    --c: var(--accent);
    position: relative; display: flex; flex-direction: column; min-height: 330px; padding: 26px 24px 22px; overflow: hidden;
    border-radius: 20px; border: 1px solid var(--line);
    background: linear-gradient(165deg, rgba(255, 255, 255, .055), rgba(255, 255, 255, .01) 45%), var(--glass);
    backdrop-filter: blur(18px); -webkit-backdrop-filter: blur(18px); box-shadow: var(--shadow);
    transform-style: preserve-3d; transition: transform .45s var(--ease), border-color .3s, box-shadow .3s;
    animation: rise .8s var(--ease) both;
}
.subj::before {
    content: ''; position: absolute; inset: -40% -40% auto auto; width: 260px; height: 260px; border-radius: 50%;
    background: radial-gradient(circle, color-mix(in srgb, var(--c) 45%, transparent), transparent 70%); opacity: .35; transition: opacity .3s;
}
.subj:hover { border-color: color-mix(in srgb, var(--c) 60%, transparent); box-shadow: 0 24px 60px rgba(0, 0, 0, .55), 0 0 40px color-mix(in srgb, var(--c) 22%, transparent); }
.subj:hover::before { opacity: .7; }
.subj .ico { position: relative; width: 66px; height: 66px; border-radius: 18px; display: grid; place-items: center; color: var(--c); background: color-mix(in srgb, var(--c) 12%, transparent); border: 1px solid color-mix(in srgb, var(--c) 35%, transparent); }
.subj .ico svg { width: 38px; height: 38px; filter: drop-shadow(0 0 8px color-mix(in srgb, var(--c) 70%, transparent)); }
.subj h3 { position: relative; margin-top: 26px; font-size: 26px; letter-spacing: 4px; }
.subj .en { font-family: var(--font-num); font-size: 11px; letter-spacing: 4px; color: var(--dim); margin-top: 4px; }
.subj .desc { position: relative; flex: 1; margin-top: 14px; font-size: 13px; line-height: 1.8; color: var(--muted); }
.subj .meta { display: flex; align-items: center; gap: 10px; margin-top: 18px; font-size: 12px; color: var(--muted); }
.subj .meta b { font-family: var(--font-num); font-size: 20px; color: var(--text); margin-right: 2px; }
.subj .bar { height: 3px; border-radius: 2px; margin-top: 12px; background: rgba(255, 255, 255, .07); overflow: hidden; }
.subj .bar i { display: block; height: 100%; border-radius: 2px; background: var(--c); box-shadow: 0 0 10px var(--c); }
.subj .tag { position: absolute; top: 22px; right: 20px; padding: 3px 10px; border-radius: 99px; font-size: 11px; letter-spacing: 1px; color: var(--c); border: 1px solid color-mix(in srgb, var(--c) 45%, transparent); background: color-mix(in srgb, var(--c) 10%, transparent); }
.subj .tag.dim { color: var(--muted); border-color: var(--line-strong); background: rgba(255, 255, 255, .03); }
.subj .go { position: absolute; right: 22px; bottom: 22px; width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center; color: var(--c); border: 1px solid color-mix(in srgb, var(--c) 40%, transparent); transition: transform .3s var(--ease), background .3s; }
.subj:hover .go { transform: translateX(3px); background: color-mix(in srgb, var(--c) 18%, transparent); }
.subj.soon { border-style: dashed; cursor: default; opacity: .75; grid-column: 1 / -1; min-height: 0; flex-direction: row; align-items: center; gap: 20px; padding: 18px 24px; }
.subj.soon .ico { width: 46px; height: 46px; border-radius: 14px; flex: none; }
.subj.soon .ico svg { width: 26px; height: 26px; }
.subj.soon h3 { margin: 0; font-size: 18px; letter-spacing: 2px; white-space: nowrap; }
.subj.soon .en { margin: 0; white-space: nowrap; }
.subj.soon .desc { margin: 0; }
.subj.soon:hover { box-shadow: var(--shadow); border-color: var(--line-strong); }

/* —— 开通管理 —— */
.pill-btn { padding: 8px 16px; border-radius: 99px; font-size: 13px; color: var(--muted); }
.pill-btn:hover { color: var(--text); }
.admin-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr); gap: 22px; margin-top: 34px; align-items: start; }
.panel { padding: 24px; }
.panel h3 { font-size: 17px; letter-spacing: 2px; }
.panel h3 em { font-style: normal; font-family: var(--font-num); font-size: 13px; color: var(--accent); margin-left: 6px; }
.panel h3.mt { margin-top: 30px; }
.panel .hint { margin: 6px 0 14px; font-size: 12px; color: var(--dim); }
.panel textarea, .panel input {
    width: 100%; padding: 10px 12px; border-radius: 10px; outline: none; resize: vertical;
    background: rgba(4, 8, 20, .55); border: 1px solid var(--line-strong); font-size: 14px; color: var(--text); font-family: inherit;
}
.panel textarea:focus, .panel input:focus { border-color: var(--accent); }
.panel .row { display: flex; gap: 10px; margin-top: 10px; }
.panel .filter { margin: 14px 0 6px; }
.btn-small { flex: none; height: 32px; padding: 0 14px; border-radius: 9px; font-size: 13px; color: var(--muted); border: 1px solid var(--line-strong); white-space: nowrap; }
.btn-small:hover { color: var(--text); background: rgba(255, 255, 255, .05); }
.btn-small.primary { color: #041018; font-weight: 700; border: 0; background: linear-gradient(100deg, #4cd7ff, #9fb2ff); }
.panel .row .btn-small { height: 40px; padding: 0 22px; }
.btn-small.danger { color: var(--rose); border-color: rgba(255, 111, 142, .35); }
.btn-small.danger:hover { background: rgba(255, 111, 142, .1); }
.list { display: flex; flex-direction: column; gap: 8px; max-height: 60vh; overflow: auto; padding-right: 4px; }
.item { display: flex; align-items: center; gap: 10px; padding: 10px 12px; border-radius: 11px; background: rgba(255, 255, 255, .03); border: 1px solid var(--line); }
.item .who { flex: 1; min-width: 0; }
.item .who b { display: block; font-size: 14px; font-weight: 500; }
.item .who span { display: block; margin-top: 3px; font-size: 12px; color: var(--dim); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.empty { padding: 18px; text-align: center; font-size: 13px; color: var(--dim); border: 1px dashed var(--line); border-radius: 11px; }
.panel .msg { text-align: left; }
.user a.admin-link { padding: 5px 12px; border-radius: 99px; font-size: 12px; color: var(--accent); border: 1px solid rgba(76, 215, 255, .35); }
.user a.admin-link:hover { background: rgba(76, 215, 255, .1); }

@media (max-width: 900px) {
    .admin-grid { grid-template-columns: 1fr; }
    .login-wrap { grid-template-columns: 1fr; gap: 30px; padding: 5vh 6vw 10vh; }
    .login-intro h1 { font-size: 38px; }
    .login-intro .chips, .login-intro p { display: none; }
}