/* Font - Franklin Gothic ATF */
@font-face {
    font-family: 'Franklin Gothic ATF';
    src: url('../assets/fonts/Franklin_Gothic_ATF.otf') format('opentype');
    font-weight: 400;
    font-style: normal;
}

@font-face {
    font-family: 'Franklin Gothic ATF';
    src: url('../assets/fonts/Franklin_Gothic_ATF_Med.otf') format('opentype');
    font-weight: 500;
    font-style: normal;
}

@font-face {
    font-family: 'Franklin Gothic ATF';
    src: url('../assets/fonts/Franklin_Gothic_ATF_Bold.otf') format('opentype');
    font-weight: 700;
    font-style: normal;
}

@font-face {
    font-family: 'Franklin Gothic ATF';
    src: url('../assets/fonts/Franklin_Gothic_ATF_Hvy.otf') format('opentype');
    font-weight: 800;
    font-style: normal;
}

/* CSS Variables */
:root {
    --coral: #E15A4A;
    --coral-dark: #D14A3A;
    --text-dark: #2D2D2D;
    --text-gray: #666666;
    --bg-light: #FAFAFA;
    --bg-footer: #F5F5F5;
    --white: #FFFFFF;
    --font-family: 'Franklin Gothic ATF', Arial, sans-serif;
}

/* Reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    color: var(--text-dark);
    background-color: var(--white);
    line-height: 1.5;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--white);
    z-index: 1000;
    padding: 20px 40px;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.logo img {
    height: 60px;
    width: auto;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-link {
    font-size: 18px;
    font-weight: 600;
    color: var(--coral);
    transition: opacity 0.2s;
}

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

.nav-link-active {
    text-decoration: underline;
    text-underline-offset: 4px;
}

/* Research Hero */
.research-hero {
    padding: 160px 40px 60px;
    display: flex;
    justify-content: center;
}

.research-content {
    max-width: 700px;
}

.research-content h1 {
    font-size: 42px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 30px;
    color: var(--text-dark);
}

.research-content .highlight {
    color: var(--coral);
}

.research-description {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-dark);
    margin-bottom: 20px;
}

/* Publications */
.research-papers {
    padding: 60px 40px 100px;
    display: flex;
    justify-content: center;
}

.research-papers-content {
    max-width: 700px;
    width: 100%;
}

.research-papers-content h2 {
    font-size: 28px;
    font-weight: 800;
    margin-bottom: 30px;
    color: var(--text-dark);
}

.papers-grid {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.paper-card {
    display: flex;
    align-items: stretch;
    gap: 20px;
    padding: 18px;
    border: 1px solid #e8e8e8;
    border-radius: 16px;
    background: var(--white);
    transition: border-color 0.2s, box-shadow 0.2s, transform 0.2s;
}

.paper-card:hover {
    border-color: var(--coral);
    box-shadow: 0 4px 20px rgba(225, 90, 74, 0.08);
    transform: translateY(-1px);
}

.paper-thumb {
    flex-shrink: 0;
    width: 110px;
    height: 110px;
    border-radius: 12px;
    overflow: hidden;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.paper-thumb-1 {
    background: linear-gradient(135deg, #E15A4A 0%, #F6A08F 100%);
}

.paper-thumb-2 {
    background: linear-gradient(135deg, #2D2D2D 0%, #5A5A5A 100%);
}

.paper-thumb-glyph {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 12px;
}

.paper-thumb-tag {
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: rgba(255, 255, 255, 0.95);
    text-align: center;
    line-height: 1.2;
}

.paper-thumb-rows {
    display: flex;
    flex-direction: column;
    gap: 4px;
    width: 60%;
}

.paper-thumb-rows i {
    height: 3px;
    border-radius: 2px;
    background: rgba(255, 255, 255, 0.85);
}

.paper-thumb-rows i:nth-child(2) { width: 80%; }
.paper-thumb-rows i:nth-child(3) { width: 65%; }
.paper-thumb-rows i:nth-child(4) { width: 90%; }
.paper-thumb-rows i:nth-child(5) { width: 50%; }

.paper-thumb-dots {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 6px;
    width: 60%;
}

.paper-thumb-dots i {
    aspect-ratio: 1;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.7);
}

.paper-thumb-dots i:nth-child(1),
.paper-thumb-dots i:nth-child(5),
.paper-thumb-dots i:nth-child(9) {
    background: var(--coral);
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.5);
}

.paper-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-width: 0;
}

.paper-title {
    font-size: 16px;
    font-weight: 700;
    line-height: 1.35;
    color: var(--text-dark);
    margin-bottom: 6px;
}

.paper-authors {
    font-size: 14px;
    color: var(--text-gray);
    margin-bottom: 2px;
}

.paper-venue {
    font-size: 13px;
    color: var(--text-gray);
    font-style: italic;
    margin-bottom: 8px;
}

.paper-link {
    font-size: 13px;
    font-weight: 600;
    color: var(--coral);
    margin-top: auto;
}

.paper-card:hover .paper-link {
    text-decoration: underline;
}

/* Footer */
.footer {
    background: var(--bg-footer);
    padding: 50px 40px;
    border-top: 1px solid #e0e0e0;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
}

.footer-brand {
    flex-shrink: 0;
}

.footer-logo {
    height: 50px;
    width: auto;
    margin-bottom: 20px;
}

.footer-brand address {
    font-style: normal;
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-gray);
    margin-bottom: 15px;
}

.footer-brand address a {
    color: var(--coral);
}

.footer-brand address a:hover {
    text-decoration: underline;
}

.copyright {
    font-size: 13px;
    color: var(--text-gray);
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        padding: 15px 20px;
    }

    .header-right {
        gap: 18px;
    }

    .nav-link {
        font-size: 15px;
    }

    .logo img {
        height: 45px;
    }

    .research-hero {
        padding: 120px 20px 40px;
    }

    .research-content h1 {
        font-size: 30px;
    }

    .research-description {
        font-size: 15px;
    }

    .research-papers {
        padding: 40px 20px 60px;
    }

    .research-papers-content h2 {
        font-size: 22px;
    }

    .paper-card {
        padding: 14px;
        gap: 14px;
    }

    .paper-thumb {
        width: 80px;
        height: 80px;
    }

    .paper-title {
        font-size: 15px;
    }

    .paper-thumb-tag {
        font-size: 9px;
    }

    .footer {
        padding: 40px 20px;
    }
}