Show daily exam countdown dialog

app/globals.css

@@ -143,3 +143,4 @@ body {
 @media(max-width:900px){.type-cards{grid-template-columns:repeat(3,1fr)}}
 @media(max-width:760px){.header-actions{align-items:flex-start;flex-direction:column}.type-cards{grid-template-columns:repeat(2,1fr)}.task-list-head{align-items:flex-start;flex-direction:column}.type-progress{text-align:left}.task-row{grid-template-columns:24px 1fr;padding:14px}.task-row small{grid-column:2}.countdown{grid-column:span 2}}
 @media(max-width:420px){.type-cards{grid-template-columns:1fr}.countdown{grid-column:auto}.task-row p{font-size:.9rem}}
+.countdown-dialog{max-width:420px!important;border:0!important;padding:30px!important;text-align:center!important;background:linear-gradient(145deg,#172554,#2563eb)!important;color:#fff!important;box-shadow:0 28px 70px #17255488!important}.dialog-kicker{margin:0;color:#bfdbfe;font-size:.78rem;font-weight:700;letter-spacing:.13em}.countdown-dialog [data-slot=dialog-title]{color:#fff;font-size:1.55rem}.countdown-dialog [data-slot=dialog-description]{color:#dbeafe;font-size:.9rem}.dialog-time{display:flex;justify-content:center;align-items:baseline;gap:7px;margin:12px 0 4px}.dialog-time b{font-size:2.7rem;line-height:1;color:#fff}.dialog-time span{font-size:.86rem;color:#bfdbfe;margin-right:3px}.dialog-note{margin:12px 0 20px;color:#dbeafe;font-size:.9rem}.dialog-button{width:100%;border:0;border-radius:12px;background:#fff;color:#1d4ed8;padding:12px;font:inherit;font-weight:700;cursor:pointer}.dialog-button:hover{background:#eff6ff}