/* ============================================
   OldNejc Game Portal - Core Styles
   Vibrant Blue + Coral + Fresh Green Palette
   ============================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --oldn-primary: #4A90D9;
    --oldn-primary-dark: #3570B0;
    --oldn-primary-light: #6BA3E0;
    --oldn-primary-bg: rgba(74, 144, 217, 0.08);
    --oldn-accent: #FF6B6B;
    --oldn-accent-light: #FF8E8E;
    --oldn-accent-bg: rgba(255, 107, 107, 0.1);
    --oldn-green: #51CF66;
    --oldn-green-bg: rgba(81, 207, 102, 0.1);
    --oldn-yellow: #FFD43B;
    --oldn-yellow-bg: rgba(255, 212, 59, 0.12);
    --oldn-dark: #2D3748;
    --oldn-dark-light: #4A5568;
    --oldn-bg: #F7FAFC;
    --oldn-bg-white: #ffffff;
    --oldn-bg-section: #EDF2F7;
    --oldn-bg-hover: #E2E8F0;
    --oldn-text: #2D3748;
    --oldn-text-secondary: #4A5568;
    --oldn-text-muted: #A0AEC0;
    --oldn-border: #E2E8F0;
    --oldn-border-light: #EDF2F7;
    --oldn-card: #ffffff;
    --oldn-shadow-sm: 0 1px 4px rgba(45,55,72,0.06);
    --oldn-shadow: 0 2px 10px rgba(45,55,72,0.08), 0 4px 20px rgba(45,55,72,0.04);
    --oldn-shadow-md: 0 4px 16px rgba(45,55,72,0.1), 0 8px 32px rgba(45,55,72,0.06);
    --oldn-shadow-hover: 0 8px 30px rgba(74,144,217,0.18), 0 16px 50px rgba(45,55,72,0.08);
    --oldn-radius: 14px;
    --oldn-radius-sm: 10px;
    --oldn-radius-lg: 18px;
    --oldn-radius-xl: 26px;
    --oldn-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --oldn-max-width: 1300px;
    --oldn-header-height: 66px;
}

html { font-size: 16px; scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
    font-family: "Nunito", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--oldn-text);
    background: var(--oldn-bg);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

a { color: inherit; text-decoration: none; transition: var(--oldn-transition); }
img { max-width: 100%; height: auto; display: block; border: 0; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* === Container === */
.oldn-container { width: 100%; max-width: var(--oldn-max-width); margin: 0 auto; padding: 0 32px; }

/* === Header - Vibrant Blue Navigation === */
.oldn-header {
    width: 100%;
    background: linear-gradient(135deg, #4A90D9 0%, #5BA0E8 100%);
    position: sticky; top: 0; z-index: 100;
    box-shadow: 0 2px 16px rgba(74,144,217,0.25);
}

.oldn-navbar {
    display: flex; align-items: center; justify-content: space-between;
    height: var(--oldn-header-height);
    max-width: var(--oldn-max-width); margin: 0 auto; padding: 0 32px;
}

.oldn-nav-brand { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.oldn-nav-logo {
    width: 42px; height: 42px; border-radius: 12px;
    object-fit: cover;
    box-shadow: 0 2px 10px rgba(0,0,0,0.15);
}
.oldn-nav-title {
    color: #fff; font-size: 1.55rem; font-weight: 800;
    letter-spacing: 0.5px;
}

.oldn-nav-toggle {
    display: none; width: 40px; height: 40px;
    align-items: center; justify-content: center;
    background: rgba(255,255,255,0.15); border-radius: 10px;
    transition: var(--oldn-transition);
}
.oldn-nav-toggle:hover { background: rgba(255,255,255,0.25); }
.oldn-nav-toggle-icon { width: 20px; height: 2px; background: #fff; position: relative; transition: var(--oldn-transition); border-radius: 2px; }
.oldn-nav-toggle-icon::before, .oldn-nav-toggle-icon::after { content: ""; position: absolute; width: 20px; height: 2px; background: #fff; left: 0; transition: var(--oldn-transition); border-radius: 2px; }
.oldn-nav-toggle-icon::before { top: -6px; }
.oldn-nav-toggle-icon::after { top: 6px; }

.oldn-nav-menu { display: flex; align-items: center; gap: 2px; }
.oldn-nav-link {
    display: block; padding: 8px 14px; color: rgba(255,255,255,0.85);
    font-size: 0.86rem; font-weight: 700; border-radius: 10px;
    transition: var(--oldn-transition); white-space: nowrap;
}
.oldn-nav-link:hover { color: #fff; background: rgba(255,255,255,0.15); }
.oldn-nav-link.is-active { color: #fff; background: rgba(255,255,255,0.22); }

/* === Main === */
.oldn-main { padding: 30px 0 60px; min-height: calc(100vh - var(--oldn-header-height) - 200px); }
.oldn-section { margin-bottom: 42px; }

.oldn-section-header {
    display: flex; align-items: center; justify-content: space-between;
    margin-bottom: 22px;
}
.oldn-section-title {
    color: var(--oldn-text); font-size: 1.3rem; font-weight: 800;
    position: relative; padding-left: 20px;
}
.oldn-section-title::before {
    content: ""; position: absolute; left: 0; top: 50%; transform: translateY(-50%);
    width: 5px; height: 24px; border-radius: 3px;
    background: linear-gradient(180deg, var(--oldn-primary), var(--oldn-accent));
}
.oldn-section-more {
    display: inline-flex; align-items: center; gap: 6px;
    color: var(--oldn-primary); font-size: 0.84rem; font-weight: 700;
    padding: 9px 20px; border-radius: 10px;
    background: var(--oldn-primary-bg); transition: var(--oldn-transition);
    border: 1.5px solid rgba(74,144,217,0.15);
}
.oldn-section-more:hover { background: var(--oldn-primary); color: #fff; border-color: var(--oldn-primary); }

/* === Game Grid === */
.oldn-game-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.oldn-game-grid--compact { grid-template-columns: repeat(4, 1fr); gap: 16px; }

/* Game Card - White + Colorful Left Border */
.oldn-game-card {
    background: var(--oldn-card); border-radius: var(--oldn-radius);
    overflow: hidden; box-shadow: var(--oldn-shadow);
    transition: var(--oldn-transition); display: flex; flex-direction: column;
    border-left: 4px solid var(--oldn-primary);
}
.oldn-game-card:hover { transform: translateY(-6px); box-shadow: var(--oldn-shadow-hover); }

.oldn-game-thumb {
    position: relative; width: 100%; aspect-ratio: 4/3; overflow: hidden;
    background: linear-gradient(135deg, #EBF4FF, #FFF5F5);
}
.oldn-game-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.oldn-game-card:hover .oldn-game-thumb img { transform: scale(1.07); }
.oldn-game-thumb-overlay {
    position: absolute; inset: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.3) 0%, transparent 50%);
    pointer-events: none; opacity: 0; transition: opacity 0.3s ease;
}
.oldn-game-card:hover .oldn-game-thumb-overlay { opacity: 1; }

.oldn-game-meta {
    display: flex; align-items: center; gap: 6px;
    margin-bottom: 6px;
}
.oldn-game-tag {
    color: #fff; font-size: 0.68rem; font-weight: 700;
    padding: 3px 10px; border-radius: 6px;
    text-transform: uppercase; letter-spacing: 0.3px;
}
.oldn-tag-boys { background: var(--oldn-primary); }
.oldn-tag-girls { background: #D53F8C; }
.oldn-tag-puzzle { background: #805AD5; }
.oldn-tag-sports { background: var(--oldn-green); color: #fff; }
.oldn-tag-strategy { background: var(--oldn-dark); }
.oldn-tag-casual { background: #DD6B20; }
.oldn-tag-popular { background: var(--oldn-accent); }
.oldn-tag-action { background: #E53E3E; }
.oldn-tag-adventure { background: #38A169; }

.oldn-game-mark {
    background: var(--oldn-yellow-bg); color: #B7791F;
    font-size: 0.72rem; font-weight: 700; padding: 3px 8px;
    border-radius: 6px;
}

.oldn-game-body { padding: 14px 16px 16px; flex: 1; display: flex; flex-direction: column; justify-content: space-between; }
.oldn-game-name {
    color: var(--oldn-text); font-size: 0.88rem; font-weight: 700;
    line-height: 1.35; margin-bottom: 4px;
    display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
    text-overflow: ellipsis; min-height: 2.3em;
}
.oldn-game-desc {
    color: var(--oldn-text-muted); font-size: 0.74rem; line-height: 1.5;
    display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}

.oldn-game-card--cover .oldn-game-body { display: none; }
.oldn-game-card--cover .oldn-game-thumb { aspect-ratio: 4/3; }
.oldn-game-card--compact { border-radius: var(--oldn-radius-sm); }
.oldn-game-card--compact .oldn-game-thumb { aspect-ratio: 4/3; }
.oldn-game-card--compact .oldn-game-name { font-size: 0.8rem; min-height: auto; -webkit-line-clamp: 1; }

/* === Channel Page === */
.oldn-channel-header {
    display: flex; align-items: center; gap: 18px;
    padding: 26px 30px; background: linear-gradient(135deg, var(--oldn-primary), var(--oldn-primary-light));
    border-radius: var(--oldn-radius-lg); margin-bottom: 28px;
    color: #fff; box-shadow: var(--oldn-shadow-md);
}
.oldn-channel-icon { width: 48px; height: 48px; object-fit: contain; filter: brightness(0) invert(1); }
.oldn-channel-title { color: #fff; font-size: 1.45rem; font-weight: 800; }

/* === Game Detail === */
.oldn-game-detail { padding: 24px 0; margin-bottom: 28px; }

/* Outer 2-col grid: main content | sidebar */
.oldn-game-detail-layout {
    display: grid; grid-template-columns: 1fr 300px; gap: 26px;
    align-items: start;
}

/* Main content card (wraps cover + meta) */
.oldn-game-detail-main {
    display: grid; grid-template-columns: 290px 1fr; gap: 30px;
    background: var(--oldn-card); border-radius: var(--oldn-radius-lg);
    padding: 26px; box-shadow: var(--oldn-shadow-md);
    border-left: 5px solid var(--oldn-primary);
}
.oldn-game-detail-cover { width: 100%; aspect-ratio: 3/4; border-radius: var(--oldn-radius); overflow: hidden; box-shadow: var(--oldn-shadow); }
.oldn-game-detail-cover img { width: 100%; height: 100%; object-fit: cover; display: block; }
.oldn-game-detail-meta { display: flex; flex-direction: column; justify-content: center; }
.oldn-game-detail-title { font-size: 1.55rem; font-weight: 800; color: var(--oldn-text); margin-bottom: 14px; line-height: 1.25; }
.oldn-game-detail-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; }
.oldn-tag {
    display: inline-block; background: var(--oldn-primary-bg); color: var(--oldn-primary);
    padding: 5px 14px; border-radius: 8px; font-size: 0.8rem; font-weight: 600;
    border: 1.5px solid rgba(74,144,217,0.15);
}
.oldn-tag--date { background: var(--oldn-yellow-bg); color: #B7791F; border-color: rgba(255,212,59,0.2); }
.oldn-game-detail-desc { color: var(--oldn-text-secondary); font-size: 0.92rem; line-height: 1.85; margin-bottom: 22px; }

.oldn-play-btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 10px;
    padding: 14px 34px; background: linear-gradient(135deg, var(--oldn-primary), var(--oldn-primary-light));
    color: #fff; font-size: 0.94rem; font-weight: 700; border-radius: 12px;
    box-shadow: 0 4px 16px rgba(74,144,217,0.35); transition: var(--oldn-transition);
    width: fit-content; letter-spacing: 0.3px;
}
.oldn-play-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(74,144,217,0.45); background: linear-gradient(135deg, var(--oldn-primary-dark), var(--oldn-primary)); }

/* Unified Sidebar */
.oldn-game-detail-sidebar {
    background: var(--oldn-card); border-radius: var(--oldn-radius-lg);
    box-shadow: var(--oldn-shadow-md); overflow: hidden;
    border-left: 5px solid var(--oldn-accent);
}
.oldn-sidebar-section {
    padding: 22px 24px;
}
.oldn-sidebar-section + .oldn-sidebar-section {
    border-top: 1px solid var(--oldn-border-light);
}
.oldn-sidebar-section-title {
    font-size: 0.86rem; font-weight: 800; color: var(--oldn-text);
    margin-bottom: 16px; text-transform: uppercase; letter-spacing: 0.3px;
}

/* Info rows inside sidebar */
.oldn-info-box-row {
    display: flex; justify-content: space-between; align-items: center;
    padding: 8px 0;
}
.oldn-info-box-row + .oldn-info-box-row {
    border-top: 1px solid var(--oldn-border-light);
}
.oldn-info-box-label { color: var(--oldn-text-muted); font-size: 0.82rem; font-weight: 600; }
.oldn-info-box-value { color: var(--oldn-text); font-size: 0.82rem; font-weight: 700; }

/* Rating inside sidebar */
.oldn-rating-stars {
    display: flex; justify-content: center; gap: 8px; margin-bottom: 8px;
}
.oldn-rating-star {
    font-size: 1.55rem; cursor: pointer; color: var(--oldn-border);
    transition: color 0.2s, transform 0.2s; line-height: 1;
}
.oldn-rating-star:hover, .oldn-rating-star.is-active {
    color: var(--oldn-yellow); transform: scale(1.15);
}
.oldn-rating-count {
    font-size: 0.78rem; color: var(--oldn-text-muted); text-align: center;
}
.oldn-rating-thanks {
    color: var(--oldn-green); font-size: 0.84rem; font-weight: 600;
    text-align: center; margin-top: 6px; display: none;
}

/* Share inside sidebar */
.oldn-share-buttons { display: flex; gap: 8px; flex-wrap: wrap; }
.oldn-share-btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 9px 14px; border-radius: 10px; font-size: 0.76rem;
    font-weight: 600; cursor: pointer; transition: var(--oldn-transition);
    border: 1.5px solid var(--oldn-border); color: var(--oldn-text-secondary);
    background: var(--oldn-bg-section);
}
.oldn-share-btn:hover {
    border-color: var(--oldn-primary); color: var(--oldn-primary);
    background: var(--oldn-primary-bg); transform: translateY(-1px);
}
.oldn-share-btn-icon { font-size: 0.95rem; line-height: 1; }
.oldn-share-btn.is-copied { background: var(--oldn-primary); color: #fff; border-color: var(--oldn-primary); }

/* Game Section Content */
.oldn-game-section {
    background: var(--oldn-card); border-radius: var(--oldn-radius);
    padding: 28px; margin-bottom: 24px; box-shadow: var(--oldn-shadow);
    border-left: 4px solid var(--oldn-accent);
}
.oldn-game-section-title {
    font-size: 1.15rem; font-weight: 800; color: var(--oldn-text);
    margin-bottom: 16px; padding-bottom: 12px; border-bottom: 2px solid var(--oldn-border);
    position: relative;
}
.oldn-game-section-title::after {
    content: ""; position: absolute; bottom: -2px; left: 0;
    width: 55px; height: 3px; background: var(--oldn-accent); border-radius: 2px;
}
.oldn-game-section-content { color: var(--oldn-text-secondary); font-size: 0.94rem; line-height: 1.85; }
.oldn-game-section-content p { margin-bottom: 14px; }
.oldn-game-section-content ul, .oldn-game-section-content ol { padding-left: 22px; margin-bottom: 14px; }
.oldn-game-section-content li { margin-bottom: 6px; list-style: disc; }
.oldn-game-section-content ol li { list-style: decimal; }
.oldn-game-section-content strong { color: var(--oldn-primary); }

.oldn-section { background: transparent; }
.oldn-section-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 22px; padding-bottom: 0; border-bottom: none; }

/* === Footer - Light Gray === */
.oldn-footer { background: var(--oldn-bg-section); color: var(--oldn-text-secondary); padding: 50px 0 26px; margin-top: 60px; border-top: 1px solid var(--oldn-border); }
.oldn-footer-inner { max-width: var(--oldn-max-width); margin: 0 auto; padding: 0 32px; }
.oldn-footer-grid { display: grid; grid-template-columns: 2.5fr 1fr 1fr 1.2fr; gap: 38px; margin-bottom: 34px; }
.oldn-footer-brand { display: flex; flex-direction: column; gap: 14px; }
.oldn-footer-brand-name { display: flex; align-items: center; gap: 12px; color: var(--oldn-text); font-size: 1.3rem; font-weight: 800; }
.oldn-footer-brand-name img { width: 38px; height: 38px; border-radius: 10px; }
.oldn-footer-brand-desc { color: var(--oldn-text-muted); font-size: 0.86rem; line-height: 1.7; }
.oldn-footer-col-title { color: var(--oldn-primary); font-size: 0.84rem; font-weight: 700; margin-bottom: 16px; text-transform: uppercase; letter-spacing: 1px; }
.oldn-footer-links { display: flex; flex-direction: column; gap: 10px; }
.oldn-footer-links a { color: var(--oldn-text-secondary); font-size: 0.86rem; transition: var(--oldn-transition); }
.oldn-footer-links a:hover { color: var(--oldn-primary); padding-left: 4px; }
.oldn-footer-bottom { text-align: center; padding-top: 26px; border-top: 1px solid var(--oldn-border); color: var(--oldn-text-muted); font-size: 0.82rem; line-height: 1.65; }
.oldn-footer-bottom a { color: var(--oldn-primary); }
.oldn-footer-bottom a:hover { color: var(--oldn-primary-dark); }

/* === Article (Legal, FAQ) === */
.oldn-article {
    max-width: 840px; margin: 0 auto; background: var(--oldn-card);
    border-radius: var(--oldn-radius-lg); padding: 38px;
    box-shadow: var(--oldn-shadow-md); border-left: 5px solid var(--oldn-primary);
}
.oldn-article h1 { font-size: 1.7rem; color: var(--oldn-text); margin-bottom: 18px; padding-bottom: 16px; border-bottom: 2px solid var(--oldn-border); font-weight: 800; }
.oldn-article h2 { font-size: 1.2rem; color: var(--oldn-text); margin: 28px 0 12px; padding-left: 16px; border-left: 4px solid var(--oldn-primary); font-weight: 700; }
.oldn-article h3 { font-size: 1.05rem; color: var(--oldn-text); margin: 20px 0 10px; font-weight: 700; }
.oldn-article p { color: var(--oldn-text-secondary); font-size: 0.94rem; line-height: 1.9; margin-bottom: 16px; }
.oldn-article ul, .oldn-article ol { padding-left: 26px; margin-bottom: 16px; }
.oldn-article li { font-size: 0.94rem; line-height: 1.75; margin-bottom: 6px; list-style: disc; color: var(--oldn-text-secondary); }
.oldn-article ol li { list-style: decimal; }
.oldn-article a { color: var(--oldn-primary); text-decoration: underline; }
.oldn-article a:hover { color: var(--oldn-primary-dark); }
.oldn-article strong { color: var(--oldn-text); }
.oldn-article .oldn-article-date { color: var(--oldn-text-muted); font-size: 0.84rem; margin-bottom: 20px; }
.oldn-article .oldn-contact-email {
    display: inline-block; background: var(--oldn-primary-bg); color: var(--oldn-primary);
    padding: 9px 20px; border-radius: 10px; font-weight: 600; margin: 10px 0 16px;
    border: 1.5px dashed rgba(74,144,217,0.2); font-size: 0.9rem;
}

/* FAQ */
.oldn-faq-item { border: 1.5px solid var(--oldn-border); border-radius: var(--oldn-radius-sm); margin-bottom: 12px; overflow: hidden; transition: var(--oldn-transition); }
.oldn-faq-item:hover { border-color: var(--oldn-primary-light); }
.oldn-faq-question {
    width: 100%; padding: 16px 20px; background: var(--oldn-bg-section);
    color: var(--oldn-text); font-size: 0.94rem; font-weight: 700; text-align: left;
    display: flex; align-items: center; justify-content: space-between; transition: var(--oldn-transition);
}
.oldn-faq-question:hover { background: var(--oldn-bg-hover); }
.oldn-faq-question::after { content: "+"; font-size: 1.35rem; color: var(--oldn-primary); transition: transform 0.3s; font-weight: 400; }
.oldn-faq-item.is-open .oldn-faq-question::after { transform: rotate(45deg); }
.oldn-faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; }
.oldn-faq-item.is-open .oldn-faq-answer { max-height: 600px; }
.oldn-faq-answer-inner { padding: 18px 20px; color: var(--oldn-text-secondary); font-size: 0.9rem; line-height: 1.85; background: var(--oldn-card); }

/* === Back to Top === */
.oldn-back-top { position: fixed; right: 24px; bottom: 74px; display: none; flex-direction: column; gap: 10px; z-index: 50; }
.oldn-back-top.is-visible { display: flex; }
.oldn-back-btn {
    width: 44px; height: 44px; background: var(--oldn-primary);
    border: none; border-radius: 12px;
    display: flex; align-items: center; justify-content: center;
    box-shadow: 0 3px 12px rgba(74,144,217,0.3); transition: var(--oldn-transition);
}
.oldn-back-btn:hover { background: var(--oldn-primary-dark); transform: translateY(-2px); box-shadow: 0 5px 18px rgba(74,144,217,0.4); }
.oldn-back-btn img { width: 18px; height: 18px; filter: brightness(0) invert(1); }

/* === Iframe (play page) === */
.oldn-iframe-wrap { position: fixed; top: 0; left: 0; width: 100vw; height: 100vh; background: #000; z-index: 9999; }
.oldn-iframe-wrap iframe, .oldn-iframe-wrap .game { display: block; width: 100%; height: 100%; border: 0; overflow: hidden; }
.oldn-iframe-back {
    position: fixed; top: 16px; left: 16px; width: 46px; height: 46px;
    background: var(--oldn-primary); border-radius: 12px;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; z-index: 10000; transition: var(--oldn-transition);
    box-shadow: 0 3px 12px rgba(74,144,217,0.35);
}
.oldn-iframe-back:hover { background: var(--oldn-primary-dark); transform: scale(1.08); }
.oldn-iframe-back img { width: 20px; height: 20px; }

/* === Responsive - Tablet === */
@media (max-width: 1024px) {
    .oldn-game-grid { grid-template-columns: repeat(3, 1fr); gap: 18px; }
    .oldn-game-detail-layout { grid-template-columns: 1fr; }
    .oldn-game-detail-main { grid-template-columns: 230px 1fr; gap: 24px; }
    .oldn-game-detail-cover { max-width: 100%; }
    .oldn-footer-grid { grid-template-columns: 1fr 1fr; gap: 26px; }
}

/* === Responsive - Mobile === */
@media (max-width: 640px) {
    :root { --oldn-header-height: 58px; }
    .oldn-container { padding: 0 16px; }
    .oldn-navbar { padding: 0 16px; }
    .oldn-nav-title { font-size: 1.25rem; }
    .oldn-nav-logo { width: 36px; height: 36px; }
    .oldn-nav-toggle { display: flex; }
    .oldn-nav-menu {
        display: none; position: absolute; top: var(--oldn-header-height);
        right: 0; left: 0;
        flex-direction: row; flex-wrap: wrap;
        background: var(--oldn-primary-dark); box-shadow: 0 6px 22px rgba(0,0,0,0.18);
        padding: 12px; gap: 6px;
    }
    .oldn-nav-menu.is-open { display: flex; }
    .oldn-nav-link {
        color: rgba(255,255,255,0.85); padding: 10px 0; border-radius: 10px;
        font-size: 0.84rem; text-align: center;
        width: calc(33.333% - 4px); background: rgba(255,255,255,0.1);
        font-weight: 600;
    }
    .oldn-nav-link:hover, .oldn-nav-link.is-active { background: rgba(255,255,255,0.2); color: #fff; }
    .oldn-game-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .oldn-game-grid--compact { grid-template-columns: repeat(3, 1fr); gap: 10px; }
    .oldn-game-body { padding: 10px 12px 12px; }
    .oldn-game-name { font-size: 0.78rem; min-height: 2em; }
    .oldn-game-desc { display: none; }
    .oldn-game-tag { font-size: 0.62rem; padding: 3px 8px; }
    .oldn-section-title { font-size: 1.1rem; }
    .oldn-section-more { font-size: 0.76rem; padding: 7px 14px; }
    .oldn-game-detail-layout { grid-template-columns: 1fr; gap: 16px; }
    .oldn-game-detail-main { grid-template-columns: 1fr; gap: 0; padding: 0; border-left-width: 4px; }
    .oldn-game-detail-cover { border-radius: var(--oldn-radius-lg) var(--oldn-radius-lg) 0 0; aspect-ratio: 16/10; max-width: none; }
    .oldn-game-detail-meta { padding: 18px 20px 22px; }
    .oldn-game-detail-title { font-size: 1.2rem; }
    .oldn-play-btn { width: 100%; max-width: none; padding: 14px 26px; font-size: 0.92rem; }
    .oldn-article { padding: 22px; }
    .oldn-article h1 { font-size: 1.3rem; }
    .oldn-article h2 { font-size: 1.05rem; }
    .oldn-article p, .oldn-article li { font-size: 0.88rem; }
    .oldn-section { margin-bottom: 28px; }
    .oldn-footer-grid { grid-template-columns: 1fr 1fr; gap: 20px; }
    .oldn-back-top { right: 14px; bottom: 64px; }
    .oldn-back-btn { width: 40px; height: 40px; }
}

/* === Breadcrumb Navigation === */
.oldn-breadcrumb {
    display: flex; align-items: center; gap: 8px;
    padding: 14px 0; margin-bottom: 10px; font-size: 0.84rem;
}
.oldn-breadcrumb a {
    color: var(--oldn-primary); font-weight: 600;
    transition: var(--oldn-transition);
}
.oldn-breadcrumb a:hover { color: var(--oldn-primary-dark); }
.oldn-breadcrumb-sep { color: var(--oldn-text-muted); font-size: 0.76rem; }
.oldn-breadcrumb-current { color: var(--oldn-text-muted); font-weight: 500; }

/* === Controls Guide Box === */
.oldn-controls-box {
    background: var(--oldn-card); border-radius: var(--oldn-radius);
    padding: 24px; box-shadow: var(--oldn-shadow);
    border-left: 4px solid var(--oldn-accent);
}
.oldn-controls-box-title {
    font-size: 0.94rem; font-weight: 800; color: var(--oldn-text);
    margin-bottom: 16px;
}
.oldn-control-row {
    display: flex; align-items: center; gap: 10px;
    padding: 6px 0; font-size: 0.84rem;
}
.oldn-control-key {
    display: inline-flex; align-items: center; justify-content: center;
    min-width: 34px; height: 30px; padding: 0 8px;
    background: var(--oldn-bg-section); border: 1.5px solid var(--oldn-border);
    border-radius: 8px; font-size: 0.74rem; font-weight: 700;
    color: var(--oldn-text); box-shadow: 0 2px 0 var(--oldn-border);
}
.oldn-control-desc { color: var(--oldn-text-secondary); font-size: 0.82rem; }

/* === Animations === */
@keyframes oldn-fade-in { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
.oldn-fade-in { animation: oldn-fade-in 0.5s ease-out; }