:root{
      --accent:#0d6efd; /* primary accent */
      --muted:#6c757d;
      --card-bg: linear-gradient(135deg, #ffffff 0%, #f8fbff 100%);
    }
    body{
      background: linear-gradient(180deg, #f6f9ff 0%, #ffffff 50%);
      font-family: "Segoe UI", Tahoma, Arial, sans-serif;
      color:#222;
    }
    .topbar{
      background:rgba(13,110,253,0.06);
      border-bottom:1px solid rgba(13,110,253,0.06);
      backdrop-filter: blur(6px);
    }
    .brand{font-weight:700; color:var(--accent);}
    .course-card{border-radius:16px; box-shadow:0 6px 18px rgba(17,24,39,0.06);}
    .course-badge{font-size:12px; padding:4px 8px; border-radius:999px;}
    .hero{padding:40px 0}

    /* certificate result */
    .cert-card{border-radius:14px; background:linear-gradient(90deg,#fff 0%, #f2f8ff 100%); box-shadow:0 8px 24px rgba(13,110,253,0.06);}

.input-group:not(.has-validation)>.dropdown-toggle:nth-last-child(n+3), .input-group:not(.has-validation)>.form-floating:not(:last-child)>.form-control, .input-group:not(.has-validation)>.form-floating:not(:last-child)>.form-select, .input-group:not(.has-validation)>:not(:last-child):not(.dropdown-toggle):not(.dropdown-menu):not(.form-floating) {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}
.input-group>:not(:first-child):not(.dropdown-menu):not(.valid-tooltip):not(.valid-feedback):not(.invalid-tooltip):not(.invalid-feedback) {
    margin-left: calc(var(--bs-border-width) * -1);
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
}
    /* responsive tweaks */
    @media (max-width:575px){
      .hero{padding:20px 0}
      .search-input{font-size:14px}
    }