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

:root {
    /* ===== 金融蓝 · 研报专业严肃风格 ===== */
    --bg: #f0f2f5;
    --surface: #ffffff;
    --surface-hover: #f4f6f9;
    --border: #d0d5dd;
    --border-light: #e5e7eb;
    --text: #101828;
    --text-secondary: #475467;
    --text-tertiary: #667085;
    --accent: #1b3a5c;
    --accent-light: #2d5f8a;
    --accent-gradient: linear-gradient(135deg, #1b3a5c, #2d5f8a);
    --gold: #b8860b;
    --gold-light: #d4a843;
    --font: "SF Pro Display", "PingFang SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
    --space-xs: 8px; --space-sm: 16px; --space-md: 24px; --space-lg: 48px; --space-xl: 80px; --space-2xl: 120px;
    --radius: 4px;
    --radius-card: 6px;
    --max-width: 1200px;
    --nav-height: 56px;
}

html { scroll-behavior: smooth; }
body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    font-size: 15px;
}

/* ===== Nav ===== */
.nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    background: rgba(27,58,92,0.97);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 2px solid var(--gold);
    height: var(--nav-height);
}
.nav-inner {
    max-width: var(--max-width); margin: 0 auto; padding: 0 var(--space-md);
    display: flex; justify-content: space-between; align-items: center;
    height: 100%;
}
.nav-brand {
    font-size: 14px; font-weight: 700; letter-spacing: 0.18em;
    color: #ffffff; text-decoration: none; flex-shrink: 0;
    font-family: "Georgia", "Times New Roman", serif;
}
.nav-links { display: flex; gap: 20px; align-items: center; flex-wrap: nowrap; overflow: hidden; flex-shrink: 0; }
.nav-links a {
    font-size: 13px; color: rgba(255,255,255,0.75); text-decoration: none;
    transition: color 0.2s; white-space: nowrap; letter-spacing: 0.04em; font-weight: 500;
}
.nav-links a:hover { color: var(--gold-light); }

/* ===== Hero ===== */
.hero {
    padding: calc(var(--nav-height) + var(--space-2xl)) var(--space-md) var(--space-xl);
    text-align: center; max-width: 800px; margin: 0 auto;
}
.hero-avatar {
    width: 120px; height: 120px; border-radius: 8px; overflow: hidden;
    margin: 0 auto var(--space-md);
    background: var(--bg); border: 2px solid var(--border);
    box-shadow: 0 2px 12px rgba(27,58,92,0.12);
}
.hero-avatar img { width: 100%; height: 100%; object-fit: cover; }
.hero-label {
    font-size: 11px; font-weight: 600; letter-spacing: 0.35em;
    color: var(--accent-light); margin-bottom: var(--space-xs);
    text-transform: uppercase;
}
.hero-name {
    font-size: 44px; font-weight: 800; line-height: 1.15;
    color: var(--accent);
    margin-bottom: var(--space-xs);
    letter-spacing: 0.02em;
}
.hero-role {
    font-size: 17px; color: var(--gold); margin-bottom: var(--space-md);
    font-weight: 600; letter-spacing: 0.05em;
}
.hero-bio {
    font-size: 15px; color: var(--text-secondary); max-width: 620px;
    margin: 0 auto var(--space-lg); line-height: 1.8;
}

/* Stats */
.stats {
    display: flex; justify-content: center; gap: 16px;
    margin-bottom: var(--space-xl); flex-wrap: wrap;
}
.stat-item {
    text-align: center; min-width: 130px;
    padding: 24px 20px 20px;
    border: 1px solid var(--border-light);
    border-radius: var(--radius-card);
    background: #ffffff;
    position: relative;
    overflow: hidden;
    transition: all 0.25s ease;
    box-shadow: 0 1px 3px rgba(27,58,92,0.04);
}
.stat-item::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0;
    height: 3px;
    background: var(--accent);
}
.stat-item:nth-child(2)::before { background: var(--gold); }
.stat-item:nth-child(3)::before { background: var(--accent-light); }
.stat-item:nth-child(4)::before { background: #5a7fa0; }
.stat-item:hover {
    border-color: var(--accent-light);
    box-shadow: 0 4px 16px rgba(27,58,92,0.1);
    transform: translateY(-2px);
}
.stat-value {
    display: block; font-size: 32px; font-weight: 800;
    color: var(--accent);
    line-height: 1;
    margin-bottom: 6px;
}
.stat-item:nth-child(2) .stat-value { color: var(--gold); }
.stat-item:nth-child(3) .stat-value { color: var(--accent-light); }
.stat-item:nth-child(4) .stat-value { color: #5a7fa0; }
.stat-label {
    display: block; font-size: 11px; color: var(--text-tertiary);
    letter-spacing: 0.06em; line-height: 1.4;
    font-weight: 500;
}

/* Philosophy */
.philosophy {
    max-width: 680px; margin: 0 auto var(--space-lg);
    padding: var(--space-lg); border-left: 4px solid var(--accent);
    text-align: left; background: #f8f9fb;
    border-radius: 0 var(--radius) var(--radius) 0;
    border: 1px solid var(--border-light);
    border-left: 4px solid var(--accent);
}
.philosophy p {
    font-size: 15px; line-height: 1.9; color: var(--text-secondary);
}
.philosophy p::before { content: '"'; font-size: 28px; color: var(--accent); font-weight: bold; font-family: Georgia, serif; }
.philosophy p::after { content: '"'; font-size: 28px; color: var(--accent); font-weight: bold; font-family: Georgia, serif; }

/* Philosophy — highlight variant (黎紫瑜) */
.philosophy.highlight {
    border-left-color: transparent;
    background: linear-gradient(135deg, rgba(27,58,92,0.04), rgba(45,95,138,0.08));
    border-radius: var(--radius);
    border: 1px solid rgba(27,58,92,0.15);
    text-align: center;
    padding: var(--space-lg) var(--space-xl);
}
.philosophy.highlight p {
    font-size: 18px; font-weight: 500; font-style: normal;
    color: var(--text);
    line-height: 1.8;
}
.philosophy.highlight p::before { content: ''; }
.philosophy.highlight p::after { content: ''; }

/* Philosophy — minimal variant (张宏第) */
.philosophy.minimal {
    border-left-color: var(--accent);
    background: var(--surface);
    border-radius: 0;
    border: 1px solid var(--border-light);
    border-left: 4px solid var(--accent);
    text-align: left;
    padding: var(--space-md) var(--space-lg);
    max-width: 400px; margin-left: auto; margin-right: auto;
}
.philosophy.minimal p {
    font-size: 20px; font-weight: 700; font-style: normal;
    color: var(--text); line-height: 1.6;
}
.philosophy.minimal p::before { content: ''; }
.philosophy.minimal p::after { content: ''; }

@media (max-width: 768px) {
    .philosophy.highlight { padding: var(--space-md) var(--space-sm); margin: 0 var(--space-sm); }
    .philosophy.highlight p { font-size: 15px; }
    .philosophy.minimal { padding: var(--space-sm) var(--space-md); margin: 0 var(--space-sm); max-width: 100%; }
    .philosophy.minimal p { font-size: 17px; }
}

/* ===== Sections ===== */
.section {
    padding: var(--space-xl) var(--space-md);
    max-width: var(--max-width); margin: 0 auto;
    border-top: 1px solid var(--border-light);
}
.section:first-of-type { border-top: none; }
.section-label {
    font-size: 11px; font-weight: 600; letter-spacing: 0.35em;
    color: var(--text-tertiary); text-transform: uppercase; margin-bottom: var(--space-xs);
}
.section-title {
    font-size: 32px; font-weight: 800; margin-bottom: var(--space-lg);
    color: var(--accent);
    position: relative;
    padding-bottom: 12px;
}
.section-title::after {
    content: '';
    position: absolute; bottom: 0; left: 0;
    width: 48px; height: 3px; background: var(--gold);
}
.section:nth-child(even) .section-title::after { background: var(--accent-light); }

/* ===== Case Cards ===== */
.case-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(340px, 1fr)); gap: 20px; }
.case-card {
    background: var(--surface); border: 1px solid var(--border-light);
    border-radius: var(--radius-card); padding: 24px;
    transition: all 0.3s ease;
    box-shadow: 0 1px 3px rgba(27,58,92,0.06); cursor: pointer;
    position: relative;
    border-left: 3px solid transparent;
}
.case-card:hover {
    border-color: var(--border);
    border-left-color: var(--accent);
    box-shadow: 0 4px 16px rgba(27,58,92,0.1);
    transform: translateY(-2px);
}
.case-tag {
    font-size: 10px; color: var(--accent-light); letter-spacing: 0.1em; text-transform: uppercase;
    display: block; margin-bottom: 8px; font-weight: 600;
}
.case-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 12px; line-height: 1.35; }
.case-status {
    font-size: 10px; padding: 2px 10px; border-radius: 3px; font-weight: 600;
    display: inline-block; margin-bottom: 14px; letter-spacing: 0.05em; text-transform: uppercase;
}
.case-status.done { background: rgba(27,58,92,0.08); color: var(--accent); border: 1px solid var(--accent); }
.case-status.ongoing { background: rgba(184,134,11,0.08); color: var(--gold); border: 1px solid var(--gold); }
.case-card .case-summary { font-size: 14px; color: var(--text-secondary); line-height: 1.7; }

/* 案例详情展开 */
.case-detail {
    max-height: 0; overflow: hidden;
    transition: max-height 0.5s ease, opacity 0.3s, margin 0.3s;
    opacity: 0; margin-top: 0;
}
.case-card.expanded .case-detail {
    max-height: 800px; opacity: 1; margin-top: 16px;
}
.case-detail h4 { font-size: 13px; font-weight: 700; color: var(--accent); margin-bottom: 6px; margin-top: 14px; text-transform: uppercase; letter-spacing: 0.05em; }
.case-detail h4:first-child { margin-top: 0; }
.case-detail p { font-size: 13px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 8px; }
.case-detail ul { font-size: 13px; color: var(--text-secondary); line-height: 1.8; padding-left: 18px; margin-bottom: 8px; }
.case-detail ul li { margin-bottom: 3px; }
.case-detail .highlight { color: var(--accent); font-weight: 700; }

/* 展开按钮 */
.case-expand {
    display: inline-flex; align-items: center; gap: 6px;
    margin-top: 16px; padding: 6px 16px;
    background: var(--surface); border: 1px solid var(--border);
    border-radius: var(--radius); font-size: 12px; font-weight: 600;
    color: var(--accent); cursor: pointer;
    transition: all 0.2s; font-family: var(--font);
    letter-spacing: 0.03em;
}
.case-expand:hover {
    background: var(--accent); border-color: var(--accent); color: #fff;
}
.case-card.expanded .case-expand {
    background: var(--accent); border-color: var(--accent); color: #fff;
}
.case-expand .arrow {
    display: inline-block; transition: transform 0.3s;
    font-size: 10px;
}
.case-card.expanded .case-expand .arrow {
    transform: rotate(180deg);
}

/* ===== Skill Cards ===== */
.skill-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: var(--space-md); }
.skill-card {
    background: var(--surface); border: 1px solid var(--border-light);
    border-radius: var(--radius-card); padding: var(--space-md);
    text-align: center; transition: all 0.3s;
    box-shadow: 0 1px 3px rgba(27,58,92,0.04);
}
.skill-card:hover {
    border-color: var(--accent-light);
    box-shadow: 0 4px 16px rgba(27,58,92,0.1);
}
.skill-icon { font-size: 32px; margin-bottom: var(--space-sm); }
.skill-card h3 { font-size: 16px; font-weight: 700; margin-bottom: var(--space-xs); color: var(--accent); }
.skill-card p { font-size: 13px; color: var(--text-secondary); }

/* ===== Qualifications ===== */
.qual-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: var(--space-sm); }
.qual-item {
    background: #f8f9fb; border: 1px solid var(--border-light);
    border-radius: var(--radius); padding: 10px var(--space-md);
    text-align: center; font-size: 12px; color: var(--text-secondary);
    font-weight: 500; letter-spacing: 0.02em;
}

/* ===== Footer ===== */
.footer {
    text-align: center; padding: var(--space-lg) var(--space-md);
    border-top: 1px solid var(--border); color: var(--text-tertiary);
    font-size: 12px; letter-spacing: 0.03em;
}
.back-link {
    display: inline-block; margin-top: var(--space-sm);
    color: var(--accent-light); text-decoration: none; font-size: 13px;
    transition: color 0.2s; font-weight: 500;
}
.back-link:hover { color: var(--gold); }

/* ===== Homepage (首页) ===== */
.home-main {
    min-height: 80vh; display: flex; align-items: center; justify-content: center;
    background: linear-gradient(180deg, var(--accent) 0%, #0d253f 100%);
}
.home-hero {
    text-align: center; padding: var(--space-2xl) var(--space-md);
}
.home-hero .logo {
    color: #ffffff !important;
    -webkit-text-fill-color: #ffffff !important;
    background: none !important;
    font-family: "Georgia", "Times New Roman", serif;
    font-size: 52px;
    letter-spacing: 0.12em;
    font-weight: 800;
}
.home-subtitle {
    font-size: 16px; color: var(--gold-light); letter-spacing: 0.35em; margin-top: var(--space-xs);
}
.home-desc {
    font-size: 15px; color: rgba(255,255,255,0.65); max-width: 480px;
    margin: var(--space-md) auto 0; line-height: 1.7;
}

/* ===== People page (二级人员介绍) ===== */
.site-header {
    text-align: center; padding: 80px var(--space-md) 48px;
    background: linear-gradient(180deg, var(--accent) 0%, #0d253f 100%);
}
.site-header .logo {
    font-size: 36px; font-weight: 800; letter-spacing: 0.12em; margin-bottom: 12px;
    color: #ffffff !important;
    -webkit-text-fill-color: #ffffff !important;
    background: none !important;
    font-family: "Georgia", "Times New Roman", serif;
}
.tagline {
    font-size: 14px; color: rgba(255,255,255,0.65); letter-spacing: 0.15em;
}
.team-grid {
    max-width: var(--max-width); margin: 0 auto;
    padding: 48px var(--space-md) 80px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}
.member-card {
    background: var(--surface); border: 1px solid var(--border-light);
    border-radius: var(--radius-card); overflow: hidden;
    text-decoration: none; color: var(--text);
    transition: all 0.3s ease; display: flex; flex-direction: column;
    box-shadow: 0 1px 3px rgba(27,58,92,0.04);
}
.member-card:hover {
    border-color: var(--accent-light);
    box-shadow: 0 8px 24px rgba(27,58,92,0.12);
    transform: translateY(-4px);
}
.member-card:hover .card-info h3 { color: var(--accent); }
.card-avatar {
    width: 100%; aspect-ratio: 1; background: #f0f2f5;
    overflow: hidden;
}
.card-avatar img { width: 100%; height: 100%; object-fit: cover; }
.card-info { padding: 20px 24px 24px; }
.card-info h3 { font-size: 19px; font-weight: 700; margin-bottom: 6px; letter-spacing: -0.01em; transition: color 0.2s; }
.card-role { font-size: 11px; color: var(--gold); margin-bottom: 10px; letter-spacing: 0.1em; font-weight: 600; }
.card-brief { font-size: 13px; color: var(--text-secondary); line-height: 1.6; }
.site-footer {
    text-align: center; padding: var(--space-lg) var(--space-md);
    border-top: 1px solid var(--border); color: var(--text-tertiary);
    font-size: 12px; letter-spacing: 0.03em;
}

/* ================================================================
   RESPONSIVE — Mobile (phones)
   ================================================================ */
@media (max-width: 768px) {
    :root {
        --space-lg: 36px; --space-xl: 56px; --space-2xl: 80px;
    }

    .nav-inner { padding: 0 6px !important; }
    .nav-links { gap: 8px !important; }
    .nav-links a { font-size: 11px !important; }
    .nav-brand { font-size: 12px !important; letter-spacing: 0.1em !important; }

    .hero {
        padding: calc(var(--nav-height) + var(--space-xl)) var(--space-sm) var(--space-lg);
    }
    .hero-avatar { width: 96px; height: 96px; border-radius: 6px; }
    .hero-name { font-size: 32px; }
    .hero-role { font-size: 15px; }
    .hero-bio { font-size: 14px; max-width: 100%; padding: 0; margin: 0 auto var(--space-md); }

    .stats {
        display: grid; grid-template-columns: 1fr 1fr;
        gap: var(--space-sm) var(--space-md);
        max-width: 320px; margin-left: auto; margin-right: auto;
    }
    .stat-item { min-width: 0; padding: 16px 12px; }
    .stat-value { font-size: 24px; }
    .stat-label { font-size: 10px; }

    .philosophy { margin: 0 var(--space-sm) var(--space-md); padding: var(--space-md); }
    .philosophy p { font-size: 14px; }

    .section { padding: var(--space-lg) var(--space-sm); }
    .section-title { font-size: 24px; }

    .case-grid { grid-template-columns: 1fr; gap: var(--space-sm); }
    .skill-grid { grid-template-columns: 1fr 1fr; gap: var(--space-sm); }
    .skill-icon { font-size: 28px; }
    .skill-card { padding: var(--space-sm); }
    .skill-card h3 { font-size: 15px; }
    .qual-grid { grid-template-columns: 1fr 1fr; gap: var(--space-xs); }
    .qual-item { padding: 10px var(--space-sm); font-size: 11px; }

    .footer { padding: var(--space-md) var(--space-sm); }
    .home-hero .logo { font-size: 32px; }
    .site-header { padding: 52px var(--space-sm) 32px; }
    .site-header .logo { font-size: 24px; }
    .team-grid { grid-template-columns: 1fr; padding: 24px var(--space-sm) 48px; gap: 12px; }
}

/* ================================================================
   RESPONSIVE — Tablet
   ================================================================ */
@media (min-width: 769px) and (max-width: 1024px) {
    .case-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-name { font-size: 38px; }
}