.theme-toggle-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
    color: var(--ink, #0C2B3A);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: color 0.2s, transform 0.2s;
    margin-left: 14px;
}
.theme-toggle-btn:hover { transform: scale(1.08); color: var(--sea); }
.theme-toggle-btn .sun-icon { display: none; }
.theme-toggle-btn .moon-icon { display: block; }
html[data-theme="dark"] .theme-toggle-btn { color: #ffb703; }
html[data-theme="dark"] .theme-toggle-btn .sun-icon { display: block; }
html[data-theme="dark"] .theme-toggle-btn .moon-icon { display: none; }

html[data-theme="dark"] {
    --paper: #0b132b;
    --paper-2: #1c2541;
    --ink: #ffffff;
    --ink-soft: #cbd5e1;
    --muted: #64748b;
    --line: #222d4a;
    --sea-deep: #4ea8de;

    background-color: #0b132b;
    color: #f8fafc;
}
html[data-theme="dark"] body { background: var(--paper-2); color: var(--ink); }

html[data-theme="dark"] nav {
    background: rgba(11, 19, 43, 0.85) !important;
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--line);
}
html[data-theme="dark"] .nav-logo { color: #fff !important; }
html[data-theme="dark"] .nav-links a { color: #cbd5e1 !important; }
html[data-theme="dark"] .nav-links a:hover { color: #5BE0A8 !important; }
html[data-theme="dark"] .nav-dropdown-trigger { color: #cbd5e1; }
html[data-theme="dark"] .nav-item-dropdown:hover .nav-dropdown-trigger { color: #fff; }
html[data-theme="dark"] .nav-submenu { background: #1c2541 !important; border-color: var(--line) !important; }
html[data-theme="dark"] .nav-submenu li a { color: #cbd5e1; }
html[data-theme="dark"] .nav-submenu li a:hover { background: #222d4a; color: #fff; }
html[data-theme="dark"] .nav-toggle { border-color: var(--line); }
html[data-theme="dark"] .nav-toggle span,
html[data-theme="dark"] .nav-toggle span::before,
html[data-theme="dark"] .nav-toggle span::after { background: #fff; }
html[data-theme="dark"] .nav-mobile-panel { background-color: #0b132b !important; border-color: var(--line) !important; }
html[data-theme="dark"] .nav-mobile-panel a { color: #fff !important; border-color: var(--line); }
html[data-theme="dark"] .mobile-dropdown-trigger { color: #fff; border-color: var(--line); }
html[data-theme="dark"] .mobile-submenu a { color: #cbd5e1; border-color: var(--line); }

html[data-theme="dark"] .nav-cta {
    background: var(--sea, #1E8A7C) !important;
    color: #ffffff !important;
}
html[data-theme="dark"] .nav-cta:hover {
    background: #5BE0A8 !important;
    color: #0b132b !important;
}

html[data-theme="dark"] footer { background: #070d1f !important; border-top: 1px solid var(--line); }
html[data-theme="dark"] footer a { color: #cbd5e1 !important; }
html[data-theme="dark"] footer a:hover { color: #5BE0A8 !important; }

html[data-theme="dark"] .fab-item {
    background: #1c2541 !important;
    color: #ffffff !important;
    border: 1px solid #222d4a !important;
}
@media (max-width: 1024px) {
    nav .nav-cta { display: none; }
}