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**Joomla → System → Site Template Styles → Helix Ultimate → Custom Code → Custom CSS**

```css
/* ===== TOP MENU CLEAN MODERN STYLE ===== */

.sp-megamenu-parent {
    gap: 8px;
}

/* TOP LEVEL BUTTONS */

.sp-megamenu-parent > li > a,
.sp-megamenu-parent > li > span {
    padding: 12px 18px !important;
    margin: 6px 4px !important;
    border-radius: 14px;
    font-size: 15px !important;
    font-weight: 600;
    line-height: 1.2;
    transition: all 0.25s ease;
    background: rgba(255,255,255,0.0);
}

/* HOVER */

.sp-megamenu-parent > li:hover > a,
.sp-megamenu-parent > li.active > a,
.sp-megamenu-parent > li:hover > span {
    background: linear-gradient(135deg,#edf5ff,#f7fbff);
    box-shadow: 0 4px 14px rgba(0,0,0,0.08);
    color: #0b2c6a !important;
}

/* DROPDOWNS */

.sp-dropdown {
    border-radius: 18px !important;
    padding: 12px !important;
    border: 1px solid rgba(0,0,0,0.05);
    box-shadow: 0 10px 35px rgba(0,0,0,0.10);
    min-width: 260px;
}

/* DROPDOWN ITEMS */

.sp-dropdown li a,
.sp-dropdown li span {
    padding: 14px 18px !important;
    border-radius: 12px;
    margin-bottom: 4px;
    font-size: 15px;
    font-weight: 500;
    transition: all 0.2s ease;
}

/* DROPDOWN HOVER */

.sp-dropdown li:hover > a,
.sp-dropdown li.active > a {
    background: linear-gradient(135deg,#edf5ff,#ffffff);
    padding-left: 24px !important;
    color: #0b2c6a !important;
}

/* MOBILE MENU */

@media (max-width: 991px) {

    .burger-icon > span {
        height: 3px;
    }

    .sp-megamenu-parent > li > a,
    .sp-megamenu-parent > li > span {
        padding: 18px 20px !important;
        font-size: 17px !important;
        border-radius: 14px;
    }

    .sp-dropdown li a,
    .sp-dropdown li span {
        padding: 18px 20px !important;
        font-size: 16px !important;
    }

    .offcanvas-menu {
        padding-top: 20px;
    }

    .offcanvas-menu .menu > li {
        margin-bottom: 8px;
    }

}

/* NETWORK MENU HIGHLIGHT REMOVED: top-level menu items now share one style. */

/* SOFT ACTIVE STATE */

.sp-megamenu-parent > li.active > a {
    background: linear-gradient(135deg,#e7f1ff,#ffffff);
}

/* REMOVE HARSH UNDERLINES */

.sp-megamenu-parent a {
    text-decoration: none !important;
}

```
/* ===== 24 NETWORK SOFT 404 / ERROR PAGE - UPDATED ===== */

.twentyfour-error-wrap {
    min-height: 100vh;
    padding: 48px 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    background:
        radial-gradient(circle at 15% 12%, rgba(109, 193, 255, 0.22), transparent 30%),
        radial-gradient(circle at 85% 18%, rgba(255, 205, 84, 0.16), transparent 28%),
        linear-gradient(135deg, #f8fbff 0%, #ffffff 52%, #f3f8fd 100%);
}

.twentyfour-error-card {
    position: relative;
    width: 100%;
    max-width: 900px;
    padding: 46px;
    overflow: hidden;
    border-radius: 34px;
    background: rgba(255,255,255,0.97);
    border: 1px solid rgba(18, 62, 120, 0.09);
    box-shadow: 0 22px 70px rgba(22, 54, 90, 0.13);
    text-align: center;
}

.twentyfour-error-visual {
    position: relative;
    width: 138px;
    height: 110px;
    margin: 0 auto 12px;
}

.twentyfour-error-orb {
    position: absolute;
    border-radius: 999px;
    filter: blur(0.2px);
}

.twentyfour-error-orb.orb-one {
    width: 82px;
    height: 82px;
    left: 8px;
    top: 18px;
    background: linear-gradient(135deg, #dff1ff, #ffffff);
    border: 1px solid rgba(37, 120, 210, 0.12);
}

.twentyfour-error-orb.orb-two {
    width: 58px;
    height: 58px;
    right: 8px;
    top: 4px;
    background: linear-gradient(135deg, #fff0bd, #ffffff);
    border: 1px solid rgba(214, 160, 22, 0.12);
}

.twentyfour-error-icon {
    position: absolute;
    left: 42px;
    top: 20px;
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 22px;
    background: linear-gradient(135deg, #0b2c6a, #1e67b8);
    color: #ffffff;
    box-shadow: 0 14px 32px rgba(16, 58, 120, 0.24);
    transform: rotate(-4deg);
}

.twentyfour-error-icon span {
    font-size: 34px;
    font-weight: 900;
    line-height: 1;
}

.twentyfour-error-code {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 74px;
    min-height: 38px;
    padding: 6px 16px;
    margin: 0 0 18px;
    border-radius: 999px;
    background: #f3f8ff;
    color: #40658f;
    border: 1px solid rgba(20, 80, 150, 0.10);
    font-weight: 800;
    letter-spacing: 0.04em;
}

.twentyfour-error-card h1 {
    margin: 0 0 12px;
    color: #10233f;
    font-size: clamp(34px, 5vw, 56px);
    line-height: 1.04;
    font-weight: 850;
}

.twentyfour-error-lead {
    max-width: 690px;
    margin: 0 auto 12px;
    color: #41566f;
    font-size: 20px;
    line-height: 1.55;
}

.twentyfour-error-small {
    max-width: 690px;
    margin: 0 auto 28px;
    color: #61748a;
    font-size: 15px;
}

.twentyfour-error-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    margin: 30px 0 34px;
}

.twentyfour-error-btn,
.twentyfour-error-btn:visited {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 50px;
    padding: 14px 21px;
    border-radius: 17px;
    background: #f3f8ff;
    color: #0b2c6a;
    font-weight: 760;
    text-decoration: none !important;
    border: 1px solid rgba(20, 80, 150, 0.10);
    transition: all 0.22s ease;
}

.twentyfour-error-btn:hover,
.twentyfour-error-btn:focus {
    background: #ffffff;
    box-shadow: 0 8px 24px rgba(22, 54, 90, 0.12);
    transform: translateY(-1px);
    color: #09234f;
}

.twentyfour-error-btn.primary {
    background: linear-gradient(135deg, #0b2c6a, #1f65b2);
    color: #ffffff;
    box-shadow: 0 10px 28px rgba(16, 58, 120, 0.20);
}

.twentyfour-error-link-panel {
    margin: 28px auto 30px;
    padding: 22px;
    max-width: 760px;
    border-radius: 24px;
    background: linear-gradient(135deg, #f8fbff, #ffffff);
    border: 1px solid rgba(20, 80, 150, 0.08);
}

.twentyfour-error-link-panel h2 {
    margin: 0 0 16px;
    color: #10233f;
    font-size: 20px;
    font-weight: 800;
}

.twentyfour-error-link-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 10px;
}

.twentyfour-error-link-grid a {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 12px 14px;
    border-radius: 15px;
    background: #ffffff;
    color: #0b2c6a;
    text-decoration: none !important;
    font-weight: 700;
    border: 1px solid rgba(20, 80, 150, 0.08);
    box-shadow: 0 5px 16px rgba(22, 54, 90, 0.05);
}

.twentyfour-error-link-grid a:hover,
.twentyfour-error-link-grid a:focus {
    background: #f4f9ff;
    box-shadow: 0 8px 22px rgba(22, 54, 90, 0.10);
}

.twentyfour-error-search {
    max-width: 720px;
    margin: 0 auto;
    text-align: left;
}

.twentyfour-error-search label {
    display: block;
    margin-bottom: 8px;
    color: #253b56;
    font-weight: 780;
}

.twentyfour-error-search-row {
    display: flex;
    gap: 10px;
}

.twentyfour-error-search input[type="search"] {
    flex: 1;
    min-height: 54px;
    padding: 0 17px;
    border-radius: 17px;
    border: 1px solid rgba(20, 80, 150, 0.16);
    background: #ffffff;
    font-size: 16px;
}

.twentyfour-error-search button {
    min-height: 54px;
    padding: 0 24px;
    border: 0;
    border-radius: 17px;
    background: #102f66;
    color: #ffffff;
    font-weight: 800;
}

@media (max-width: 700px) {
    .twentyfour-error-wrap {
        padding: 22px 12px;
        align-items: flex-start;
    }

    .twentyfour-error-card {
        padding: 30px 18px;
        border-radius: 24px;
    }

    .twentyfour-error-actions {
        display: grid;
        grid-template-columns: 1fr;
    }

    .twentyfour-error-btn {
        width: 100%;
        min-height: 58px;
        font-size: 16px;
    }

    .twentyfour-error-link-grid {
        grid-template-columns: 1fr;
    }

    .twentyfour-error-link-grid a {
        min-height: 56px;
        font-size: 16px;
    }

    .twentyfour-error-search-row {
        display: grid;
        grid-template-columns: 1fr;
    }

    .twentyfour-error-search input[type="search"],
    .twentyfour-error-search button {
        width: 100%;
        min-height: 58px;
        font-size: 16px;
    }
}

/* ===== 24YachtSuppliers top menu normalisation ===== */
#sp-header .sp-megamenu-parent > li > a,
#sp-header .sp-megamenu-parent > li > span {
    padding: 12px 18px !important;
    margin: 6px 4px !important;
    border: 0 !important;
    outline: 0 !important;
    border-radius: 14px !important;
    box-shadow: none;
    font-size: 15px !important;
    font-weight: 600 !important;
    line-height: 1.2 !important;
    background: transparent;
    color: #042461 !important;
}

#sp-header .sp-megamenu-parent > li:hover > a,
#sp-header .sp-megamenu-parent > li:hover > span,
#sp-header .sp-megamenu-parent > li.active > a,
#sp-header .sp-megamenu-parent > li.current-item > a {
    border: 0 !important;
    outline: 0 !important;
    background: linear-gradient(135deg,#edf5ff,#f7fbff) !important;
    box-shadow: 0 4px 14px rgba(0,0,0,0.08) !important;
    color: #0b2c6a !important;
}

#sp-header .sp-megamenu-parent > li:last-child > a,
#sp-header .sp-megamenu-parent > li:last-child > span,
#sp-header .sp-megamenu-parent > li:last-child.active > a,
#sp-header .sp-megamenu-parent > li:last-child.current-item > a {
    border: 0 !important;
    outline: 0 !important;
}