/* Scroll-to-top button */
.scroll-top-btn {
    position: fixed;
    bottom: 30px;
    left: 30px;
    width: 46px;
    height: 46px;
    border-radius: 50%;
    background: rgba(0, 20, 10, 0.55);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(110, 231, 183, 0.5);
    color: #6ee7b7;
    font-size: 22px;
    cursor: pointer;
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.35s ease;
    opacity: 0;
    pointer-events: none;
    transform: translateY(20px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.5);
    -webkit-tap-highlight-color: transparent;
}
.scroll-top-btn.visible {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}
.scroll-top-btn:hover,
.scroll-top-btn:active {
    background: rgba(110, 231, 183, 0.2);
    border-color: #a7f3d0;
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.7);
    transform: translateY(-4px);
}

/* ═══════════════════════════════════════
   📱 MOBILE STYLES
   ═══════════════════════════════════════ */
@media (max-width: 900px) {
    .glass-nav {
        border-radius: 30px;
        padding: 10px 16px;
        flex-wrap: wrap;
        gap: 6px;
        top: 10px;
        margin-bottom: 24px;
    }
    .glass-nav.scrolled {
        border-radius: 24px;
        padding: 8px 14px;
    }
    .logo {
        font-size: 20px;
        letter-spacing: 1px;
    }
    .menu-btn {
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 24px;
        padding: 8px 12px;
        order: 3;
    }
    .social-icons {
        order: 2;
        gap: 8px;
        margin-right: auto;
        margin-left: 8px;
    }
    .social-icons a {
        width: 34px;
        height: 34px;
    }
    .social-icons img {
        width: 18px;
        height: 18px;
    }
    .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        gap: 4px;
        order: 10;
        padding-top: 4px;
    }
    #menu-toggle:checked~.nav-links {
        display: flex;
    }
    #menu-toggle:checked~.social-icons {
        margin-bottom: 6px;
    }
    .nav-links a {
        width: 100%;
        text-align: center;
        padding: 12px 16px;
        font-size: 15px;
        border-radius: 16px;
        min-height: 46px;
        display: flex;
        align-items: center;
        justify-content: center;
    }
    .nav-links a:active {
        background: rgba(110, 231, 183, 0.3);
        transform: scale(0.97);
    }

    .main-container {
        padding: 12px;
    }

    .glass-card {
        border-radius: var(--mobile-radius);
        padding: 16px;
        margin-bottom: 18px;
    }
    .glass-card:hover {
        transform: none;
        box-shadow: var(--shadow), inset 0 0.5px 1px rgba(255, 255, 255, 0.25);
    }

    .section-title {
        font-size: 20px;
        gap: 8px;
        margin-bottom: 12px;
    }
    .section-icon {
        font-size: 28px;
    }

    .rule-list {
        gap: 10px;
        margin-top: 8px;
    }
    .rule-item {
        font-size: 14px;
        gap: 10px;
        padding: 12px 14px;
        border-radius: 14px;
        line-height: 1.7;
    }
    .rule-item:hover {
        transform: none;
    }
    .rule-item:active {
        background: rgba(110, 231, 183, 0.15);
        border-color: rgba(110, 231, 183, 0.5);
    }
    .rule-number {
        width: 28px;
        height: 28px;
        font-size: 12px;
        flex-shrink: 0;
    }

    .accordion-list {
        gap: 8px;
    }
    .accordion-item {
        border-radius: 14px;
    }
    .accordion-item:hover {
        transform: none;
        box-shadow: 0 8px 25px rgba(0, 0, 0, 0.4), inset 0 1px 1px rgba(255, 255, 255, 0.15);
    }
    .accordion-header {
        font-size: 15px;
        padding: 12px 14px;
        gap: 10px;
        min-height: 48px;
    }
    .accordion-number {
        width: 26px;
        height: 26px;
        font-size: 12px;
    }
    .accordion-arrow {
        font-size: 16px;
    }
    .accordion-content {
        padding: 0 14px;
    }
    .accordion-content-inner {
        font-size: 13px;
        padding-bottom: 12px;
        line-height: 1.75;
    }
    .glossary-list {
        padding-right: 12px;
    }
    .glossary-list li {
        font-size: 13px;
        margin-bottom: 4px;
    }

    .glass-footer {
        border-radius: 24px;
        padding: 16px;
        font-size: 12px;
        margin-top: 20px;
    }

    .scroll-top-btn {
        bottom: 20px;
        left: 16px;
        width: 40px;
        height: 40px;
        font-size: 18px;
        border-radius: 50%;
    }
}

@media (max-width: 480px) {
    .glass-nav {
        border-radius: 22px;
        padding: 8px 12px;
        top: 8px;
        margin-bottom: 18px;
    }
    .glass-nav.scrolled {
        border-radius: 18px;
        padding: 6px 10px;
    }
    .logo {
        font-size: 17px;
        letter-spacing: 0.5px;
    }
    .menu-btn {
        font-size: 22px;
        padding: 6px 10px;
    }
    .social-icons a {
        width: 30px;
        height: 30px;
    }
    .social-icons img {
        width: 16px;
        height: 16px;
    }
    .social-icons {
        gap: 6px;
        margin-left: 4px;
    }
    .nav-links a {
        padding: 10px 14px;
        font-size: 13px;
        border-radius: 12px;
        min-height: 40px;
    }
    .glass-card {
        border-radius: 14px;
        padding: 12px;
        margin-bottom: 14px;
    }
    .section-title {
        font-size: 18px;
        gap: 6px;
    }
    .section-icon {
        font-size: 24px;
    }
    .rule-item {
        font-size: 13px;
        padding: 10px 12px;
        gap: 8px;
        border-radius: 12px;
    }
    .rule-number {
        width: 24px;
        height: 24px;
        font-size: 11px;
    }
    .accordion-header {
        font-size: 13px;
        padding: 10px 12px;
        gap: 8px;
        min-height: 42px;
    }
    .accordion-number {
        width: 24px;
        height: 24px;
        font-size: 11px;
    }
    .accordion-content-inner {
        font-size: 12px;
        line-height: 1.7;
    }
    .glass-footer {
        border-radius: 18px;
        padding: 12px;
        font-size: 11px;
    }
    .scroll-top-btn {
        bottom: 16px;
        left: 12px;
        width: 36px;
        height: 36px;
        font-size: 16px;
    }
}

/* ─── Reduced motion ─────────────────── */
@media (prefers-reduced-motion: reduce) {
    .bg-orb,
    .particle {
        animation: none !important;
    }
    .glass-card,
    .rule-item,
    .accordion-item,
    .glass-footer {
        transition: opacity 0.3s ease !important;
    }
    html {
        scroll-behavior: auto;
    }
}