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

:root {
    --bg: #ffffff;
    --bg-alt: #f7f8f9;
    --border: #e8e9eb;
    --black: #111111;
    --gray-400: #888888;
    --gray-600: #555555;
    --accent: #2337ff;
    --accent-light: rgba(35, 55, 255, 0.05);
    --radius: 4px;
    --max-width: 1000px;
    --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

html { scroll-behavior: smooth; }

body {
    font-family: var(--font);
    color: var(--black);
    background: var(--bg);
    line-height: 1.6;
    font-size: 15px;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 32px;
}

/* === Header === */
.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border);
}

.nav {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 32px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 56px;
}

.logo {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--black);
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 28px;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray-600);
    font-size: 0.82rem;
    font-weight: 400;
    transition: color 0.15s;
}

.nav-links a:hover { color: var(--black); }

.nav-cta {
    background: var(--accent);
    color: #fff !important;
    padding: 6px 14px;
    border-radius: var(--radius);
    font-weight: 500;
}

.nav-cta:hover { opacity: 0.8; }

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    flex-direction: column;
    gap: 4px;
}

.nav-toggle span {
    display: block;
    width: 18px;
    height: 1.5px;
    background: var(--black);
}

/* === Hero === */
.hero {
    padding: 100px 0 80px;
    background: var(--bg-alt);
    border-bottom: 1px solid var(--border);
}

.hero-tag {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.18em;
    color: var(--gray-400);
    margin-bottom: 20px;
}

.hero h1 {
    font-size: 3.2rem;
    font-weight: 600;
    line-height: 1.12;
    letter-spacing: -0.035em;
    margin-bottom: 24px;
    color: var(--black);
}

.hero-desc {
    max-width: 460px;
    font-size: 1rem;
    color: var(--gray-600);
    line-height: 1.7;
    margin-bottom: 40px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    align-items: center;
}

.btn {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    padding: 11px 24px;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.85rem;
    border: none;
    cursor: pointer;
    transition: opacity 0.15s, box-shadow 0.2s;
    box-shadow: 0 2px 8px rgba(35, 55, 255, 0.15);
}

.btn:hover {
    opacity: 0.85;
    box-shadow: 0 4px 16px rgba(35, 55, 255, 0.25);
}

.btn-ghost {
    background: none;
    color: var(--gray-600);
    padding: 11px 0;
}

.btn-ghost:hover { color: var(--black); opacity: 1; }

/* === Sections === */
.section {
    padding: 80px 0;
    border-top: 1px solid var(--border);
}

.section-alt {
    background: var(--bg-alt);
}

.section-dark {
    background: var(--bg-alt);
    color: var(--black);
    border-top: 1px solid var(--border);
}

.section-dark h2 { color: var(--black); }
.section-dark .section-tag { color: var(--gray-400); }

.section-tag {
    font-size: 0.62rem;
    text-transform: uppercase;
    letter-spacing: 0.22em;
    color: var(--gray-400);
    margin-bottom: 8px;
}

.section h2 {
    font-size: 1.6rem;
    font-weight: 600;
    margin-bottom: 48px;
    color: var(--black);
    letter-spacing: -0.02em;
}

/* === Grid === */
.grid {
    display: grid;
    gap: 1px;
    background: var(--border);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* === Cards === */
.card {
    padding: 32px 24px;
    background: var(--bg);
    transition: box-shadow 0.2s, transform 0.2s;
}

.card:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.05);
    transform: translateY(-2px);
}

.card-num {
    display: block;
    font-size: 0.65rem;
    color: var(--accent);
    margin-bottom: 14px;
    letter-spacing: 0.05em;
    font-weight: 600;
}

.card h3 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--black);
}

.card p {
    font-size: 0.82rem;
    color: var(--gray-600);
    line-height: 1.65;
}

/* === Stats === */
.section-dark .grid {
    background: var(--border);
    border-color: var(--border);
}

.stat {
    padding: 40px 24px;
    text-align: center;
    background: var(--bg);
    transition: box-shadow 0.2s;
}

.stat:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.04);
}

.stat-num {
    display: block;
    font-size: 2.4rem;
    font-weight: 600;
    letter-spacing: -0.03em;
    margin-bottom: 4px;
    color: var(--accent);
}

.stat-label {
    font-size: 0.7rem;
    color: var(--gray-600);
    letter-spacing: 0.06em;
}

/* === Cases === */
.cases-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.case-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 28px 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    gap: 24px;
    transition: box-shadow 0.2s, transform 0.2s;
}

.case-item:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.05);
    transform: translateY(-1px);
}

.case-item:first-child {
    padding-top: 28px;
}

.case-item:last-child {
    border-bottom: 1px solid var(--border);
    padding-bottom: 28px;
}

.case-info { flex: 1; }

.case-tag {
    display: inline-block;
    font-size: 0.62rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--accent);
    font-weight: 600;
    margin-bottom: 4px;
}

.case-info h3 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--black);
}

.case-info p {
    font-size: 0.82rem;
    color: var(--gray-600);
    line-height: 1.55;
}

.case-result {
    text-align: right;
    flex-shrink: 0;
}

.case-result span {
    display: block;
    font-size: 1.6rem;
    font-weight: 600;
    color: var(--black);
    letter-spacing: -0.02em;
}

.case-result small {
    font-size: 0.6rem;
    color: var(--gray-400);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

/* === About === */
.about-content {
    max-width: 560px;
}

.about-content p {
    color: var(--gray-600);
    font-size: 0.92rem;
    margin-bottom: 16px;
    line-height: 1.8;
}

.about-content p:last-child { margin-bottom: 0; }

/* === News === */
.news-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.news-item {
    display: flex;
    gap: 24px;
    padding: 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: box-shadow 0.2s, transform 0.2s;
}

.news-item:hover {
    box-shadow: 0 4px 16px rgba(0,0,0,0.05);
    transform: translateY(-1px);
}

.news-item-link {
    text-decoration: none;
    color: inherit;
    align-items: center;
}

.news-arrow {
    flex-shrink: 0;
    font-size: 1.2rem;
    color: var(--gray-400);
    transition: color 0.2s;
}

.news-item-link:hover .news-arrow {
    color: var(--accent);
}

.news-date {
    flex-shrink: 0;
    font-size: 0.75rem;
    color: var(--gray-400);
    padding-top: 2px;
    min-width: 80px;
}

.news-info {
    flex: 1;
}

.news-info h3 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--black);
}

.news-info p {
    font-size: 0.82rem;
    color: var(--gray-600);
    line-height: 1.6;
}

/* Page header */
.page-header {
    padding-bottom: 0;
    border-top: none;
}

.page-title {
    font-size: 2rem;
    font-weight: 600;
    color: var(--black);
    letter-spacing: -0.02em;
}

/* Active nav link */
.active-link {
    color: var(--black) !important;
    font-weight: 500 !important;
}

/* Back link */
.back-link {
    display: inline-block;
    margin-bottom: 32px;
    font-size: 0.82rem;
    color: var(--gray-400);
    text-decoration: none;
    transition: color 0.15s;
}

.back-link:hover {
    color: var(--accent);
}

/* Article detail */
.article-date {
    display: block;
    font-size: 0.75rem;
    color: var(--gray-400);
    margin-bottom: 12px;
}

.article-title {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--black);
    letter-spacing: -0.02em;
    margin-bottom: 32px;
    line-height: 1.3;
}

.article-content {
    max-width: 640px;
}

.article-content p {
    font-size: 0.92rem;
    color: var(--gray-600);
    line-height: 1.9;
    margin-bottom: 16px;
}

.article-content p:last-child {
    margin-bottom: 0;
}

/* === Contact === */
.contact-form-wrap {
    max-width: 560px;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.contact-form input,
.contact-form textarea {
    padding: 11px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 0.85rem;
    font-family: inherit;
    background: var(--bg);
    color: var(--black);
    transition: border-color 0.15s;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
    color: var(--gray-400);
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--accent);
}

.contact-form textarea {
    resize: none;
}

.contact-form .btn {
    align-self: flex-start;
    margin-top: 6px;
}

/* === Footer === */
.footer {
    border-top: 1px solid var(--border);
    padding: 48px 0 24px;
    background: #f0f1f3;
}

.footer-top {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 32px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--border);
}

.footer-col h4 {
    font-size: 0.82rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--black);
}

.footer-col p {
    font-size: 0.82rem;
    color: var(--gray-600);
    margin-bottom: 4px;
    line-height: 1.7;
}

.footer-col .highlight {
    color: var(--accent);
    font-weight: 500;
    margin-top: 6px;
}

.footer-brand {
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--black);
    display: block;
    margin-bottom: 8px;
}

.footer-desc {
    font-size: 0.8rem;
    color: var(--gray-400);
    line-height: 1.6;
}

.footer-bottom {
    text-align: center;
    font-size: 0.72rem;
    color: var(--gray-400);
}

/* === Responsive === */
@media (max-width: 768px) {
    .container { padding: 0 20px; }
    .nav { padding: 0 20px; }

    .nav-toggle { display: flex; }

    .nav-links {
        display: none;
        position: absolute;
        top: 56px;
        left: 0;
        right: 0;
        background: var(--bg);
        flex-direction: column;
        padding: 24px 20px;
        gap: 16px;
        border-bottom: 1px solid var(--border);
    }

    .nav-links.active { display: flex; }

    .hero { padding: 60px 0 48px; }
    .hero h1 { font-size: 2.2rem; }

    .grid-3 { grid-template-columns: 1fr; }
    .grid-4 { grid-template-columns: 1fr 1fr; }

    .case-item { flex-direction: column; align-items: flex-start; }
    .case-result { text-align: left; margin-top: 8px; }

    .contact-grid { grid-template-columns: 1fr; gap: 36px; }
    .form-row { grid-template-columns: 1fr; }

    .section { padding: 56px 0; }
    .section h2 { margin-bottom: 32px; }

    .footer-top { grid-template-columns: 1fr 1fr; gap: 24px; }
}