:root { color-scheme: dark; font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; color: #edf2ff; background: radial-gradient(circle at 15% 0%, #173067 0, transparent 38%), #080d19; }
main { width: min(1080px, calc(100% - 40px)); margin: 0 auto; padding: 70px 0; }
header { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; }
.eyebrow { color: #7ea2ff; font-size: 13px; font-weight: 700; letter-spacing: .14em; text-transform: uppercase; }
h1 { margin: 16px 0 10px; font-size: clamp(44px, 7vw, 70px); line-height: 1; letter-spacing: -.045em; }
.lead { margin: 0; color: #9aa9c4; font-size: 18px; line-height: 1.7; }
.notice, .signed-out { margin-top: 54px; padding: 30px; border: 1px solid rgba(148,174,225,.2); border-radius: 22px; background: rgba(19,29,51,.72); }
.signed-out h2 { margin-top: 0; }
.signed-out p { color: #9aa9c4; line-height: 1.7; }
.primary, button { display: inline-flex; align-items: center; justify-content: center; min-height: 42px; padding: 0 18px; color: #fff; text-decoration: none; border: 0; border-radius: 12px; background: #285ee8; font-weight: 700; cursor: pointer; }
.secondary { border: 1px solid rgba(148,174,225,.25); background: rgba(19,29,51,.72); }
.identity { display: flex; align-items: center; gap: 14px; margin-top: 44px; padding: 18px 20px; border: 1px solid rgba(148,174,225,.18); border-radius: 18px; background: rgba(19,29,51,.6); }
.avatar { display: grid; width: 44px; height: 44px; place-items: center; border-radius: 14px; background: #285ee8; font-weight: 800; }
.identity strong, .identity div span { display: block; }
.identity div span { margin-top: 3px; color: #8490a4; font-size: 13px; }
.session-badge { margin-left: auto; color: #8fb0ff; font-size: 13px; }
.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin-top: 22px; }
.card { position: relative; display: block; min-height: 250px; padding: 28px; overflow: hidden; color: inherit; text-decoration: none; border: 1px solid rgba(148,174,225,.20); border-radius: 24px; background: rgba(19,29,51,.72); box-shadow: 0 26px 70px rgba(0,0,0,.23); transition: transform .2s ease, border-color .2s ease; }
.card:hover { transform: translateY(-4px); border-color: rgba(126,162,255,.65); }
.card.disabled { opacity: .48; cursor: not-allowed; }
.card.disabled:hover { transform: none; border-color: rgba(148,174,225,.20); }
.icon { display: grid; width: 48px; height: 48px; place-items: center; border-radius: 14px; background: #285ee8; font-size: 22px; font-weight: 800; }
.icon.zentao { background: #16a274; }
.card h2 { margin: 26px 0 8px; font-size: 24px; }
.card p { margin: 0; color: #9aa9c4; line-height: 1.65; }
.arrow { position: absolute; top: 29px; right: 29px; color: #7ea2ff; font-size: 24px; }
.account { position: absolute; left: 28px; bottom: 25px; color: #8fb0ff; font-size: 13px; }
footer { display: flex; justify-content: space-between; gap: 24px; margin-top: 34px; color: #657491; font-size: 13px; }
[hidden] { display: none !important; }
@media (max-width: 860px) { .grid { grid-template-columns: 1fr; } .card { min-height: 210px; } }
@media (max-width: 580px) { main { padding: 46px 0; } header, footer { flex-direction: column; } .session-badge { display: none; } }