/* =============================================
   RVJO.YAN - TESLA STYLE
   Dark Theme + Futuristic Design
   Trilingual: EN / ZH / KO
   ============================================= */

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-primary: #070d0a;
    --bg-secondary: #0a1410;
    --bg-card: #0f1a15;
    --text-primary: #f0f4f2;
    --text-secondary: #c8ddd3;
    --text-muted: #6fa892;
    --accent: #34c77a;
    --accent-hover: #52dba0;
    --border: #162820;
    --shadow: rgba(0, 0, 0, 0.5);
    --tint-1: #142420;
    --tint-2: #101e18;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* --- Header --- */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100000;
    background: rgba(7, 13, 10, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    box-shadow: inset 0 -1px 0 rgba(52, 199, 122, 0.12);
    box-shadow: inset 0 -1px 0 rgba(52, 199, 122, 0.12);
    box-shadow: inset 0 -1px 0 rgba(52, 199, 122, 0.12);
    box-shadow: inset 0 -1px 0 rgba(52, 199, 122, 0.12);
    box-shadow: inset 0 -1px 0 rgba(52, 199, 122, 0.12);
    box-shadow: inset 0 -1px 0 rgba(52, 199, 122, 0.12);
    padding: 0 40px;
    height: 60px;
    display: flex;
    align-items: center;
}

.header-left {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    gap: 15px;
}

.header-right {
    position: relative;
    left: 0;
    transform: none;
    display: flex;
    align-items: center;
    gap: 2px;
    flex: 1;
    justify-content: center;
    padding: 0 140px 0 20px;
    overflow: visible;
    box-sizing: border-box;
}

.lang-switcher {
    position: relative;
    flex-shrink: 0;
    z-index: 100001;
    padding-bottom: 6px; /* 桥接按钮与下拉菜单的hover区域，防止鼠标移开时下拉消失 */
}
.lang-switcher:hover .lang-dropdown,
.lang-dropdown.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
}

.header-logo {
    height: 36px;
    width: auto;
    filter: invert(1);
}



.nav-btn {
    display: inline-block;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 14px;
    padding: 8px 16px;
    cursor: pointer;
    transition: all 0.25s;
    letter-spacing: 0.5px;
    text-decoration: none;
}

.nav-btn:hover {
    color: var(--text-primary);
}

.nav-btn.active {
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.08em;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 6px;
}

/* Language Switcher */


.lang-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 20px;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.3s;
}

.lang-btn:hover {
    border-color: var(--accent);
    color: var(--text-primary);
}

.lang-dropdown {
    position: absolute;
    top: calc(100% + 6px); /* 视觉间隙，无hover断层 */
    right: 0;
    background: rgba(10, 20, 16, 0.98);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 6px;
    width: max-content;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.2s;
    pointer-events: none;
}

.lang-dropdown.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
}

.lang-option {
    display: block;
    width: 100%;
    background: none;
    border: none;
    color: var(--text-secondary);
    padding: 8px 12px;
    text-align: left;
    cursor: pointer;
    border-radius: 4px;
    font-size: 14px;
    transition: all 0.2s;
    text-decoration: none;
}

.lang-option:hover {
    background: rgba(52, 199, 122, 0.18);
    color: var(--text-primary);
}

.lang-option.active {
    color: var(--accent);
}

/* --- Main Content --- */
    main.container {
    margin-top: 60px;
}

/* --- Hero Section (Home) --- */
.hero {
    height: calc(100vh - 60px);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.hero img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.3;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    padding: 0 20px;
}

.hero-title {
    font-size: 56px;
    font-weight: 600;
    letter-spacing: -1px;
    margin-bottom: 20px;
    background: linear-gradient(135deg, #f0f4f2 0%, #6fa892 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--text-secondary);
    font-weight: 300;
}

/* --- Container --- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 30px 40px;
}

/* --- Section Titles --- */
.section-title {
    font-size: 40px;
    font-weight: 600;
    letter-spacing: -0.5px;
    margin-bottom: 40px;
    text-align: center;
    background: linear-gradient(135deg, #f0f4f2, #34c77a);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* --- Bio Page (Apple-style, inspired by wujing.team) --- */
.pi-profile {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 48px;
    margin-bottom: 56px;
    padding: 40px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
}

.pi-profile img {
    width: 200px;
    height: auto;
    border-radius: 8px;
    flex-shrink: 0;
    box-shadow: 0 0 20px rgba(52, 199, 122, 0.15);
    border: 1.5px solid rgba(52, 199, 122, 0.3);
}

.pi-profile .pi-text {
    flex: 1;
}

.pi-profile .pi-name {
    font-size: 32px;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
    background: linear-gradient(135deg, #f0f4f2, #34c77a);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.pi-profile .pi-bio {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.7;
}

.pi-profile .pi-bio p {
    margin-bottom: 12px;
}

.info-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 56px;
}

.info-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 32px;
    border: 1px solid var(--border);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.info-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.info-card h3 {
    font-size: 20px;
    font-weight: 600;
    letter-spacing: -0.01em;
    margin-bottom: 16px;
    color: var(--accent);
}

.info-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.65;
    margin-bottom: 8px;
}

.info-card p:last-child {
    margin-bottom: 0;
}

.info-card p strong {
    color: var(--text-primary);
}

/* --- Publication Page --- */
.pub-section {
    margin-bottom: 60px;
}

.pub-section h2 {
    font-size: 28px;
    font-weight: 500;
    margin-bottom: 24px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border);
}

.pub-list {
    list-style: none;
}

.pub-list li {
    padding: 12px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.6;
}

.pub-list li a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.2s;
}

.pub-list li a:hover {
    color: var(--accent-hover);
}

/* --- Responsive --- */
@media (max-width: 1200px) {
    .header-right {
        gap: 1px;
    }
    .nav-btn {
        padding: 6px 8px;
        font-size: 13px;
    }
}

@media (max-width: 768px) {
    /* Note: header/nav responsive rules are in the unified 768px block below */
    .nav-btn {
        padding: 6px 10px;
        font-size: 13px;
    }
    .hero-title {
        font-size: 36px;
    }
    .container {
        padding: 40px 20px;
    }
    .pi-profile {
        flex-direction: column;
        text-align: center;
        padding: 24px;
        gap: 24px;
    }
    .pi-profile img {
        width: 160px;
        height: 160px;
    }
    .pi-profile .pi-name {
        font-size: 22px;
    }
    .pi-profile .pi-bio {
        text-align: left;
    }
    .info-grid {
        grid-template-columns: 1fr;
    }
}

/* ---- Bio Page - Card Layout ---- */
.profile-card {
    display: flex;
    gap: 32px;
    background: var(--bg-card, rgba(14,26,20,0.7));
    border-radius: 20px;
    padding: 36px;
    border: 1px solid rgba(255,255,255,0.05);
    margin-bottom: 28px;
    align-items: flex-start;
}
.profile-photo {
    width: 200px;
    height: auto;
    object-fit: cover;
    border-radius: 12px;
    flex-shrink: 0;
    box-shadow: 0 4px 16px rgba(0,0,0,0.25);
}
.profile-info h1 {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary, #e8f5e9);
    margin: 0 0 12px 0;
    letter-spacing: -0.02em;
}
.profile-info p {
    font-size: 15.5px;
    line-height: 1.75;
    color: var(--text-secondary, #a8c4b8);
    margin: 0;
}
.info-card h2 {
    font-size: 19px;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: #34c77a;
    margin-bottom: 18px;
}
@media (max-width: 700px) {
    .profile-card {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 20px;
        padding: 24px;
    }
    .profile-info h1 { font-size: 26px; }
}

/* =============================================
   MOBILE RESPONSIVE - Comprehensive
   ============================================= */

@media (max-width: 900px) {
    .container {
        padding: 40px 24px;
    }
    .hero-title {
        font-size: 40px;
    }
    .section-title {
        font-size: 30px;
    }
}

@media (max-width: 768px) {
    /* --- Header --- */
    .header {
        padding: 0 16px;
        flex-wrap: wrap;
        height: auto;
        min-height: 56px;
        gap: 6px;
    }
    .header-left {
        gap: 10px;
    }
    .header-logo {
        height: 30px;
    }
    .header-right {
        position: static;
        transform: none;
        flex: 1;
        min-width: 0;
        justify-content: center;
        flex-wrap: nowrap;
        gap: 0;
        padding: 0;
        display: flex;
        align-items: center;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    .header-right::-webkit-scrollbar { display: none; }
    .nav-btn {
        padding: 7px 6px;
        font-size: 12px;
        white-space: nowrap;
        flex-shrink: 0;
    }
    .nav-btn.active {
        font-size: 12.5px;
    }
    .lang-switcher {
        position: relative;
        margin-left: 0;
        flex-shrink: 0;
    }
    .lang-btn {
        padding: 4px 8px;
        font-size: 18px;
    }
    .lang-dropdown {
        right: 0;
        left: auto;
    }

    /* --- Main & Container (46px top spacing) --- */
    main.container {
        margin-top: 60px;
    }

    /* --- Container --- */
    .container {
        max-width: 100%;
        margin: 0 auto;
        padding: 20px 20px;
    }

    /* --- Hero (Home) --- */
    .hero {
        height: calc(100vh - 56px);
        min-height: 400px;
    }
    .hero-content {
        padding: 0 16px;
    }
    .hero-title {
        font-size: 32px;
        margin-bottom: 14px;
    }
    .hero-subtitle {
        font-size: 16px;
    }

    /* --- Section Titles --- */
    .section-title {
        font-size: 26px;
        margin-bottom: 28px;
    }

    /* --- Bio Page --- */
    .profile-card {
        flex-direction: column;
        align-items: center;
        text-align: center;
        padding: 24px 20px;
        gap: 20px;
    }
    .profile-photo {
        width: 160px;
        height: auto;
    }
    .profile-info h1 {
        font-size: 24px;
    }
    .profile-info p {
        font-size: 14px;
        text-align: left;
    }
    .info-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    .info-card {
        padding: 24px 20px;
    }
    .info-card h2 {
        font-size: 17px;
        margin-bottom: 14px;
    }
    .info-card p {
        font-size: 14px;
    }

    /* --- Footer --- */
    footer {
        padding: 24px 16px !important;
        margin-top: 40px !important;
    }
    footer p {
        font-size: 12px !important;
    }
}

@media (max-width: 480px) {
    main.container {
        margin-top: 60px;
    }
    .container {
        padding: 20px 16px;
    }
    .hero-title {
        font-size: 24px;
    }
    .hero-subtitle {
        font-size: 14px;
    }
    .hero {
        min-height: 320px;
    }
    .section-title {
        font-size: 22px;
        margin-bottom: 24px;
    }
    .nav-btn {
        padding: 5px 6px;
        font-size: 11px;
    }
    .nav-btn.active {
        font-size: 11.5px;
    }
    .header-right {
        gap: 1px;
    }
    .profile-photo {
        width: 140px;
    }
    .profile-info h1 {
        font-size: 20px;
    }
    .profile-info p {
        font-size: 13px;
    }
    .info-card {
        padding: 18px 16px;
    }
    .info-card h2 {
        font-size: 15px;
    }
    .info-card p {
        font-size: 13px;
    }
}