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

:root {
    --color-primary: #000000;
    --color-text: #1a1a1a;
    --color-text-light: #666666;
    --color-accent: #c4572a;
    --color-bg: #ffffff;
    --color-bg-alt: #fafafa;
    --color-border: #e5e5e5;
    --font-stack: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --container-width: 1200px;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-stack);
    color: var(--color-text);
    line-height: 1.6;
    font-size: 17px;
    background: var(--color-bg);
}

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

a:hover {
    color: #a3461f;
}

/* Container */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
}

.nav-inner {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 16px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
    letter-spacing: -0.5px;
}

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

.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    color: var(--color-text-light);
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--color-primary);
}

/* Hamburger */
.nav-hamburger {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-hamburger span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    margin: 6px 0;
    transition: transform 0.3s, opacity 0.3s;
}

/* Mobile nav */
@media (max-width: 768px) {
    .nav-hamburger {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        padding: 24px;
        gap: 20px;
        border-bottom: 1px solid var(--color-border);
    }

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

    .nav-links a {
        font-size: 17px;
    }
}

/* Hero */
.hero {
    padding: 160px 0 100px;
    text-align: center;
}

.hero h1 {
    font-size: 64px;
    font-weight: 700;
    letter-spacing: -2px;
    line-height: 1.1;
    margin-bottom: 24px;
}

.hero .tagline {
    font-size: 20px;
    color: var(--color-text-light);
    max-width: 640px;
    margin: 0 auto 40px;
    line-height: 1.6;
}

@media (max-width: 768px) {
    .hero {
        padding: 120px 0 60px;
    }

    .hero h1 {
        font-size: 40px;
        letter-spacing: -1px;
    }

    .hero .tagline {
        font-size: 17px;
    }
}

/* Sections */
.section {
    padding: 50px 0;
}

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

.section h2 {
    font-size: 40px;
    font-weight: 700;
    letter-spacing: -1.5px;
    margin-bottom: 16px;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

.section h3 {
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.5px;
    margin-bottom: 12px;
}

.section p {
    color: var(--color-text-light);
    margin-bottom: 16px;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

@media (max-width: 768px) {
    .section {
        padding: 40px 0;
    }

    .section h2 {
        font-size: 32px;
    }
}

/* Page header */
.page-header {
    padding: 140px 0 60px;
    border-bottom: 1px solid var(--color-border);
    text-align: center;
}

.page-header h1 {
    font-size: 48px;
    font-weight: 700;
    letter-spacing: -1.5px;
    margin-bottom: 16px;
}

.page-header p {
    font-size: 18px;
    color: var(--color-text-light);
    max-width: 640px;
    margin-left: auto;
    margin-right: auto;
}

@media (max-width: 768px) {
    .page-header {
        padding: 120px 0 40px;
    }

    .page-header h1 {
        font-size: 36px;
    }
}

/* Cards */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 32px;
    margin-top: 40px;
}

.card {
    padding: 32px;
    border: 1px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-bg);
    transition: box-shadow 0.2s;
}

.card:hover {
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.card h3 {
    margin-bottom: 8px;
}

.card p {
    font-size: 15px;
    color: var(--color-text-light);
}

/* Team */
.team-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 40px;
    margin-top: 40px;
}

.team-member {
    width: 240px;
    text-align: center;
}

.team-member .avatar {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    background: var(--color-bg-alt);
    margin: 0 auto 16px;
    overflow: hidden;
    border: 1px solid var(--color-border);
}

.team-member .avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.team-member h3 {
    font-size: 18px;
    margin-bottom: 4px;
}

.team-member .role {
    font-size: 15px;
    color: var(--color-text-light);
}

.team-member .bio {
    font-size: 14px;
    color: var(--color-text-light);
    margin-top: 8px;
    max-width: 280px;
    margin-left: auto;
    margin-right: auto;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--color-accent);
    color: #fff;
}

.btn-primary:hover {
    background: #a3461f;
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(196, 87, 42, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--color-accent);
    border: 2px solid var(--color-accent);
}

.btn-outline:hover {
    background: var(--color-accent);
    color: #fff;
}

.btn-group {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

/* Job listings */
.job-list {
    margin-top: 0;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.job-card {
    border: 1px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-bg);
    overflow: hidden;
}

.job-card-header {
    padding: 24px 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 24px;
}

.job-card-header h3 {
    margin-bottom: 4px;
}

.job-meta {
    font-size: 14px;
    color: var(--color-text-light);
    margin-top: 8px;
}

.job-meta div {
    margin-bottom: 2px;
}

.job-expand-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    color: var(--color-accent);
    padding: 8px 0;
    margin-top: 8px;
}

.job-expand-btn:hover {
    color: #a3461f;
}

.job-expand-btn .arrow {
    display: inline-block;
    transition: transform 0.2s;
    font-size: 12px;
}

.job-card.open .job-expand-btn .arrow {
    transform: rotate(180deg);
}

.job-details {
    display: none;
    padding: 0 28px 24px;
    border-top: 1px solid var(--color-border);
}

.job-card.open .job-details {
    display: block;
    padding-top: 24px;
}

.job-details h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
    margin-top: 20px;
    color: var(--color-text);
}

.job-details h4:first-child {
    margin-top: 0;
}

.job-details ul {
    list-style: disc;
    padding-left: 20px;
    color: var(--color-text-light);
    font-size: 15px;
}

.job-details ul li {
    margin-bottom: 6px;
}

.job-details .btn {
    margin-top: 20px;
}

@media (max-width: 768px) {
    .job-card-header {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* Agenda */
.agenda-intro {
    margin-bottom: 48px;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

.agenda-intro ul {
    list-style: disc;
    padding-left: 24px;
    margin: 12px auto 16px;
    color: var(--color-text-light);
    max-width: 720px;
}

.agenda-intro ul li {
    margin-bottom: 6px;
}

.agenda-item {
    padding: 48px 0;
    border-top: 1px solid var(--color-border);
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

.agenda-item h3 {
    font-size: 22px;
    font-weight: 600;
    letter-spacing: -0.5px;
    margin-bottom: 16px;
    color: var(--color-text);
}

.agenda-item p {
    color: var(--color-text-light);
    margin-bottom: 16px;
    max-width: 720px;
}

/* Readings */
.reading-list {
    margin-top: 32px;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

.reading-item {
    padding: 20px 0;
    border-bottom: 1px solid var(--color-border);
}

.reading-item:first-child {
    border-top: 1px solid var(--color-border);
}

.reading-item .reading-number {
    font-size: 15px;
    font-weight: 600;
    color: var(--color-text-light);
    margin-bottom: 4px;
}

.reading-item .reading-title {
    font-size: 17px;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 4px;
}

.reading-item .reading-authors {
    font-size: 15px;
    color: var(--color-text-light);
}

.reading-item .reading-year {
    font-size: 14px;
    color: var(--color-text-light);
    margin-top: 2px;
}

/* Papers */
.paper-list {
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

.paper-item {
    padding: 24px 0;
    border-bottom: 1px solid var(--color-border);
}

.paper-item:first-child {
    border-top: 1px solid var(--color-border);
}

.paper-item .paper-title {
    font-size: 17px;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 4px;
}

.paper-item .paper-authors {
    font-size: 15px;
    color: var(--color-text-light);
}

.paper-item .paper-year {
    font-size: 14px;
    color: var(--color-text-light);
    margin-top: 2px;
}

.paper-item .paper-description {
    font-size: 15px;
    color: var(--color-text-light);
    margin-top: 12px;
}

.paper-abstract-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    color: var(--color-accent);
    padding: 8px 0;
    margin-top: 8px;
}

.paper-abstract-btn:hover {
    color: #a3461f;
}

.paper-abstract-btn .arrow {
    display: inline-block;
    transition: transform 0.2s;
    font-size: 12px;
}

.paper-item.open .paper-abstract-btn .arrow {
    transform: rotate(180deg);
}

.paper-abstract {
    display: none;
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid var(--color-border);
}

.paper-item.open .paper-abstract {
    display: block;
}

.paper-abstract p {
    font-size: 15px;
    color: var(--color-text-light);
}

.paper-disclaimer {
    font-size: 14px;
    color: var(--color-text-light);
    margin-top: 16px;
}

/* Footer */
.footer {
    padding: 40px 0;
    border-top: 1px solid var(--color-border);
    text-align: center;
    color: var(--color-text-light);
    font-size: 14px;
}

.footer a {
    color: var(--color-text-light);
}

.footer a:hover {
    color: var(--color-primary);
}