/* ===== RESET & BASE ===== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Segoe UI', Roboto, Arial, sans-serif;
    font-size: 14px;
    line-height: 1.6;
    color: #333;
    background: #f5f7fa;
}

a { color: #2980b9; }

/* ===== NAVBAR ===== */
.navbar {
    background: #2c3e50;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.nav-inner {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
}

.brand {
    color: #fff;
    font-weight: 700;
    font-size: 16px;
    padding: 14px 20px;
    text-decoration: none;
    letter-spacing: 0.5px;
}

.brand span { color: #3498db; }

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

.nav-links a {
    color: #bdc3c7;
    text-decoration: none;
    padding: 14px 14px;
    font-size: 13px;
    font-weight: 500;
    transition: background 0.2s, color 0.2s;
    border-bottom: 3px solid transparent;
}

.nav-links a:hover {
    background: #34495e;
    color: #fff;
}

.nav-links a.active {
    border-bottom-color: #3498db;
    color: #fff;
    background: #34495e;
}

/* ===== CONTAINER ===== */
.container {
    max-width: 960px;
    margin: 30px auto;
    padding: 0 20px;
}

.container-card {
    max-width: 960px;
    margin: 30px auto;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    padding: 40px;
}

/* ===== PAGE HEADER ===== */
h1.page-title {
    font-size: 28px;
    color: #2c3e50;
    margin-bottom: 8px;
    padding-bottom: 12px;
    border-bottom: 3px solid var(--accent, #3498db);
}

.subtitle {
    color: #7f8c8d;
    font-size: 14px;
    margin-bottom: 30px;
}

/* ===== YEAR HEADER ===== */
.year-header {
    background: #2c3e50;
    color: #fff;
    padding: 8px 16px;
    border-radius: 4px;
    font-size: 18px;
    font-weight: 600;
    margin: 30px 0 16px 0;
    display: inline-block;
}

/* ===== PAPER CARD ===== */
.paper {
    background: #fdfdfd;
    border: 1px solid #e8ecf0;
    border-left: 4px solid var(--accent, #3498db);
    border-radius: 4px;
    padding: 16px 20px;
    margin-bottom: 12px;
    transition: box-shadow 0.2s;
}

.paper:hover {
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}

.paper-number {
    display: inline-block;
    background: var(--accent, #3498db);
    color: #fff;
    font-weight: 700;
    font-size: 11px;
    width: 30px;
    height: 30px;
    line-height: 30px;
    text-align: center;
    border-radius: 50%;
    margin-right: 10px;
    float: left;
    margin-top: 2px;
}

.paper-content {
    margin-left: 46px;
}

.paper-title {
    font-size: 15px;
    font-weight: 600;
    color: #990000;
    margin-bottom: 4px;
}

.paper-authors {
    font-size: 13px;
    color: #555;
    margin-bottom: 4px;
}

.paper-venue {
    font-size: 13px;
    color: #444;
    margin-bottom: 8px;
}

.paper-venue em {
    font-weight: 600;
    font-style: italic;
}

.paper-links {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
}

/* ===== BADGES & BUTTONS ===== */
.doi-badge {
    display: inline-block;
    background: #e8f5e9;
    border: 1px solid #a5d6a7;
    color: #2e7d32;
    font-size: 12px;
    font-family: 'Courier New', monospace;
    padding: 3px 8px;
    border-radius: 3px;
    text-decoration: none;
    word-break: break-all;
}

.doi-badge:hover {
    background: #c8e6c9;
    text-decoration: underline;
}

.link-btn {
    display: inline-block;
    font-size: 12px;
    padding: 3px 10px;
    border-radius: 3px;
    text-decoration: none;
    border: 1px solid #ccc;
    color: #555;
    background: #fafafa;
}

.link-btn:hover {
    background: #eee;
    color: #333;
}

.tag {
    display: inline-block;
    font-size: 11px;
    padding: 2px 6px;
    border-radius: 3px;
    background: #fcf8e3;
    border: 1px solid #f0ad4e;
    color: #8a6d3b;
    font-weight: 600;
}

.tag.award {
    background: #dff0d8;
    border-color: #5cb85c;
    color: #3c763d;
}

/* ===== SECTION HEADER ===== */
.section-header {
    background: #2c3e50;
    color: #fff;
    padding: 8px 16px;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 600;
    margin: 30px 0 16px 0;
    display: inline-block;
}

/* ===== CARDS (HOME) ===== */
.card {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    padding: 30px 40px;
    margin-bottom: 24px;
}

.card h2 {
    font-size: 20px;
    color: #2c3e50;
    margin-bottom: 16px;
    border-bottom: 2px solid #3498db;
    padding-bottom: 8px;
}

/* ===== FOOTER ===== */
footer {
    margin-top: 40px;
    padding-top: 16px;
    border-top: 1px solid #e8ecf0;
    color: #999;
    font-size: 12px;
    text-align: center;
}

/* ===== CLEARFIX ===== */
.clearfix::after {
    content: "";
    display: table;
    clear: both;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .nav-inner {
        flex-direction: column;
        align-items: flex-start;
    }
    .nav-links { width: 100%; }
    .nav-links a { padding: 10px 14px; }
    .container-card { padding: 20px; margin: 15px; }
    .card { padding: 20px; }
    .paper-content { margin-left: 0; margin-top: 10px; }
    .paper-number { float: none; }
}