/* ==========================================================================
   Simer Conference — clean academic conference design
   ========================================================================== */

:root {
	--simer-primary: #173f7a;
	--simer-primary-dark: #0f2c59;
	--simer-accent: #f0a030;
	--simer-text: #262b33;
	--simer-muted: #5b6472;
	--simer-bg: #ffffff;
	--simer-bg-alt: #f3f6fb;
	--simer-border: #e2e8f0;
	--simer-footer-bg: #0d1f3c;
	--simer-footer-text: #c4d2e8;
	--simer-radius: 8px;
	--simer-container: 1140px;
	--simer-page-banner-from: #173f7a;
	--simer-page-banner-to: #0f2c59;
	--simer-page-banner-title: #ffffff;
	--simer-date-card-bg: #ffffff;
	--simer-home-cfp-card-bg: #ffffff;
	--simer-logo-card-bg: #ffffff;
	--simer-expert-card-bg: #ffffff;
	--simer-speaker-card-bg: #ffffff;
	--simer-cfp-track-card-bg: #ffffff;
}

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

body {
	margin: 0;
	font-family: -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
	color: var(--simer-text);
	background: var(--simer-bg);
	line-height: 1.65;
	-webkit-font-smoothing: antialiased;
	display: flex;
	flex-direction: column;
	min-height: 100vh;
}

h1, h2, h3, h4, h5, h6 { line-height: 1.3; color: var(--simer-text); }
a { color: var(--simer-primary); }
a:hover { color: var(--simer-primary-dark); }
img { max-width: 100%; height: auto; }

.container { max-width: var(--simer-container); margin: 0 auto; padding: 0 20px; }

.screen-reader-text {
	position: absolute; width: 1px; height: 1px;
	overflow: hidden; clip: rect(1px, 1px, 1px, 1px);
}

/* ---------- Buttons ---------- */

.btn {
	display: inline-block;
	padding: 10px 24px;
	border-radius: var(--simer-radius);
	background: var(--simer-accent);
	color: #fff;
	font-weight: 600;
	text-decoration: none;
	transition: background .15s ease, transform .15s ease;
}
.btn:hover { background: var(--simer-primary); color: #fff; transform: translateY(-1px); }
.btn-small { padding: 7px 16px; font-size: .9rem; }

/* ---------- Header (shared + 3 layouts) ---------- */

.site-header {
	background-color: var(--header-bg, var(--simer-bg));
	background-image: var(--header-bg-image, none);
	background-size: cover;
	background-position: center center;
	background-repeat: no-repeat;
	border-bottom: 3px solid var(--simer-primary);
	position: sticky;
	top: 0;
	z-index: 60;
	box-shadow: 0 1px 4px rgba(13, 31, 60, .07);
}

.site-branding {
	display: flex;
	align-items: center;
	gap: 12px;
	text-decoration: none;
}
.site-logo {
	max-height: 68px;
	width: auto;
	margin-right: 8px;
}
.site-title {
	font-size: 1.35rem;
	font-weight: 700;
	color: var(--header-title, var(--simer-primary));
	white-space: nowrap;
}

.primary-menu {
	display: flex;
	flex-wrap: wrap;
	gap: 2px;
	list-style: none;
	margin: 0;
	padding: 0;
}
.primary-menu a {
	display: block;
	padding: 9px 12px;
	text-decoration: none;
	color: var(--header-menu, var(--simer-text));
	font-weight: 600;
	font-size: .92rem;
	border-radius: var(--simer-radius);
	white-space: nowrap;
	transition: background .15s, color .15s;
}
.primary-menu a:hover,
.primary-menu .current-menu-item > a {
	background: var(--header-menu-hover, var(--simer-primary));
	color: #fff;
}

.nav-toggle {
	display: none;
	flex-direction: column;
	gap: 5px;
	background: none;
	border: 0;
	padding: 10px;
	cursor: pointer;
}
.nav-toggle-bar { width: 26px; height: 3px; background: var(--simer-primary); border-radius: 2px; }

/* v1 — Inline: logo + menu one row */
.site-header--inline .site-header-inner {
	display: flex;
	align-items: center;
	justify-content: space-between;
	flex-wrap: wrap;
	gap: 8px 20px;
	min-height: 78px;
	padding-top: 6px;
	padding-bottom: 6px;
}

/* v2 — Bar: brand row + full-width menu bar */
.site-header--bar {
	border-bottom: 0;
	position: sticky;
}
.site-header--bar .site-header-brand-row {
	border-bottom: 1px solid var(--simer-border);
}
.site-header--bar .site-header-brand-inner {
	display: flex;
	align-items: center;
	justify-content: space-between;
	min-height: 72px;
	padding-top: 8px;
	padding-bottom: 8px;
}
.site-header--bar .site-header-nav-row {
	background: var(--header-menu-hover, var(--simer-primary));
}
.site-header--bar .site-header-nav-inner {
	display: flex;
	align-items: center;
	justify-content: center;
	min-height: 44px;
}
.site-header--bar .primary-menu {
	justify-content: center;
	width: 100%;
}
.site-header--bar .primary-menu a {
	color: #fff;
	border-radius: 0;
	padding: 12px 14px;
}
.site-header--bar .primary-menu a:hover,
.site-header--bar .primary-menu .current-menu-item > a {
	background: rgba(255, 255, 255, .18);
	color: #fff;
}

/* v3 — Centered: logo above, menu below */
.site-header--centered .site-header-inner {
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	gap: 10px;
	padding-top: 14px;
	padding-bottom: 12px;
	position: relative;
}
.site-header--centered .site-branding {
	justify-content: center;
	text-align: center;
	flex-wrap: wrap;
}
.site-header--centered .site-title {
	white-space: normal;
	text-align: center;
	line-height: 1.25;
	max-width: 900px;
}
.site-header--centered .site-nav {
	width: 100%;
}
.site-header--centered .primary-menu {
	justify-content: center;
}
.site-header--centered .nav-toggle {
	position: absolute;
	top: 14px;
	right: 12px;
}

/* ---------- Sticky footer support ---------- */

.site-main { flex: 1 0 auto; width: 100%; }

/* ---------- Hero carousel ---------- */

.hero-carousel {
	position: relative;
	overflow: hidden;
	background: var(--simer-primary-dark);
}
.hero-slide {
	display: none;
	animation: simer-fade .6s ease;
}
.hero-slide.is-active { display: block; }
.hero-slide img {
	display: block;
	width: 100%;
	max-height: 480px;
	object-fit: cover;
}
@keyframes simer-fade { from { opacity: .3; } to { opacity: 1; } }

.hero-dots {
	position: absolute;
	bottom: 16px;
	left: 0; right: 0;
	display: flex;
	justify-content: center;
	gap: 10px;
}
.hero-dot {
	width: 12px; height: 12px;
	border-radius: 50%;
	border: 2px solid #fff;
	background: transparent;
	padding: 0;
	cursor: pointer;
}
.hero-dot.is-active { background: var(--simer-accent); border-color: var(--simer-accent); }

/* ---------- Sections ---------- */

.section { padding: 56px 0; }
.section-alt { background: var(--simer-bg-alt); }

.section-title {
	text-align: center;
	font-size: 1.75rem;
	margin: 0 0 30px;
}
.section-title::after {
	content: "";
	display: block;
	width: 56px;
	height: 3px;
	background: var(--simer-accent);
	margin: 12px auto 0;
	border-radius: 2px;
}

.section-body { max-width: 900px; margin: 0 auto; }

.rich-text > :first-child { margin-top: 0; }
.rich-text > :last-child { margin-bottom: 0; }

/* ---------- Rich-text tables (Registration Guideline, Program, etc.) ---------- */

.rich-text table {
	width: 100%;
	max-width: 100%;
	border-collapse: collapse;
	background: var(--simer-bg);
	margin: 24px 0;
	font-size: .96rem;
}
.rich-text table th,
.rich-text table td {
	padding: 12px 16px;
	border: 1px solid var(--simer-border);
	text-align: left;
	vertical-align: top;
}
.rich-text table thead th {
	background: var(--simer-primary);
	color: #fff;
	font-weight: 700;
}
.rich-text table tbody tr:nth-child(even) { background: var(--simer-bg-alt); }
.rich-text table tbody tr:hover { background: #eef3fb; }
.rich-text table caption {
	caption-side: top;
	text-align: left;
	padding: 6px 0 12px;
	color: var(--simer-muted);
	font-style: italic;
}
@media (max-width: 720px) {
	.rich-text table th,
	.rich-text table td { padding: 9px 10px; font-size: .92rem; }
}

/* ---------- Date cards ---------- */

.date-cards {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
	gap: 18px;
}
.date-card {
	background: var(--simer-date-card-bg, var(--simer-bg));
	border: 1px solid var(--simer-border);
	border-top: 4px solid var(--simer-accent);
	border-radius: var(--simer-radius);
	padding: 22px 16px;
	text-align: center;
	box-shadow: 0 2px 8px rgba(13, 31, 60, .05);
}
.date-card-title {
	font-size: .85rem;
	color: var(--simer-muted);
	text-transform: uppercase;
	letter-spacing: .04em;
}
.date-card-desc {
	font-size: 1.15rem;
	font-weight: 700;
	color: var(--simer-primary);
	margin-top: 6px;
}

/* ---------- CFP blocks / tracks ---------- */

.cfp-blocks,
.cfp-tracks {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
	gap: 24px;
}
.cfp-block {
	background: var(--simer-home-cfp-card-bg, var(--simer-bg));
	border: 1px solid var(--simer-border);
	border-radius: var(--simer-radius);
	padding: 26px;
}
.cfp-track {
	background: var(--simer-cfp-track-card-bg, var(--simer-bg));
	border: 1px solid var(--simer-border);
	border-radius: var(--simer-radius);
	padding: 26px;
}
.cfp-block-title,
.cfp-track-title {
	margin-top: 0;
	color: var(--simer-primary);
	border-bottom: 2px solid var(--simer-accent);
	padding-bottom: 10px;
	display: inline-block;
}
.cfp-top { margin-bottom: 26px; }

/* ---------- Logo cards (publications / organizers) ---------- */

.logo-cards {
	display: flex;
	flex-wrap: wrap;
	justify-content: center;
	gap: 22px;
}
.logo-card {
	background: var(--simer-logo-card-bg, var(--simer-bg));
	border-radius: var(--simer-radius);
	padding: 20px 26px;
	text-align: center;
	min-width: 200px;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	gap: 10px;
}
.logo-card img { max-height: 90px; width: auto; object-fit: contain; }
.logo-card-name { font-weight: 600; color: var(--simer-primary); }

/* ---------- Page banner ---------- */

.page-banner {
	background: linear-gradient(120deg, var(--simer-page-banner-from), var(--simer-page-banner-to));
	padding: 52px 0;
}
.page-title {
	color: var(--simer-page-banner-title);
	margin: 0;
	font-size: clamp(1.5rem, 3vw, 2.1rem);
}

.content-area { padding: 46px 20px 60px; }

/* ---------- Committee ---------- */

.committee-group { margin-bottom: 40px; }
.committee-group-title {
	color: var(--simer-primary);
	border-left: 4px solid var(--simer-accent);
	padding-left: 12px;
	font-size: 1.25rem;
	font-weight: 700;
	margin-bottom: 24px;
}
.expert-cards {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 24px;
}
.expert-card {
	background: var(--simer-expert-card-bg, var(--simer-bg));
	border: 1px solid var(--simer-border);
	border-radius: var(--simer-radius);
	padding: 24px;
	display: flex;
	flex-direction: column;
	align-items: center;
	text-align: center;
}
.expert-avatar {
	width: 120px;
	height: 140px;
	object-fit: cover;
	border-radius: var(--simer-radius);
	margin-bottom: 16px;
	border: 1px solid var(--simer-primary-dark);
}
.expert-name {
	font-size: 1.15rem;
	font-weight: 700;
	color: var(--simer-primary);
	margin: 0 0 8px;
}
.expert-type {
	color: var(--simer-accent);
	font-size: 0.95rem;
	font-weight: 600;
	margin-bottom: 8px;
}
.expert-place {
	color: var(--simer-muted);
	font-size: 0.9rem;
	line-height: 1.5;
}

/* ---------- Speakers ---------- */

.speaker-cards { display: grid; gap: 24px; }
.speaker-card {
	display: flex;
	gap: 26px;
	background: var(--simer-speaker-card-bg, var(--simer-bg));
	border: 1px solid var(--simer-border);
	border-radius: var(--simer-radius);
	padding: 28px;
	align-items: flex-start;
}
.speaker-avatar {
	width: 170px;
	height: 190px;
	object-fit: cover;
	border-radius: var(--simer-radius);
	flex-shrink: 0;
}
.speaker-name { margin: 0 0 10px; color: var(--simer-primary); }
.speaker-intro { font-size: .95rem; }

/* ---------- Download table ---------- */

.download-table {
	width: 100%;
	border-collapse: collapse;
	background: var(--simer-bg);
}
.download-table th,
.download-table td {
	padding: 13px 16px;
	border: 1px solid var(--simer-border);
	text-align: left;
}
.download-table thead th { background: var(--simer-primary); color: #fff; }
.download-table tbody tr:nth-child(even) { background: var(--simer-bg-alt); }

/* ---------- Contact ---------- */

.contact-card {
	display: flex;
	gap: 40px;
	background: var(--simer-bg);
	border: 1px solid var(--simer-border);
	border-radius: var(--simer-radius);
	padding: 30px;
	align-items: flex-start;
}
.contact-details { flex: 1; }
.contact-row {
	display: flex;
	gap: 14px;
	padding: 10px 0;
	border-bottom: 1px solid var(--simer-border);
}
.contact-row:last-child { border-bottom: 0; }
.contact-label {
	font-weight: 700;
	color: var(--simer-primary);
	min-width: 110px;
}
.contact-wechat { text-align: center; }
.contact-wechat img {
	width: 160px;
	height: 160px;
	object-fit: cover;
	border: 1px solid var(--simer-border);
	border-radius: var(--simer-radius);
}
.contact-wechat-label { color: var(--simer-muted); margin-top: 8px; }

/* ---------- Footer ---------- */

.site-footer {
    background: var(--simer-footer-bg);
    color: var(--simer-footer-text);
    margin-top: 40px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* Main content area - stretch to footer */
.content-area {
    padding: 46px 20px 60px;
    flex: 1;
}

/* Responsive adjustment */
@media (max-width: 720px) {
    .content-area {
        padding-bottom: 80px;
    }
}
.footer-inner { padding: 26px 20px; text-align: center; }
.footer-inner p { margin: 4px 0; }
.footer-site-title {
	font-size: 1.2rem;
	font-weight: 700;
	color: #fff;
	margin: 0 0 8px;
	letter-spacing: .02em;
}
.site-footer a { color: var(--simer-footer-text); }

/* ---------- Responsive ---------- */

@media (max-width: 1024px) {
	.nav-toggle { display: flex; }
	.site-nav {
		display: none;
		position: absolute;
		top: 100%;
		left: 0; right: 0;
		background: var(--header-bg, var(--simer-bg));
		border-bottom: 3px solid var(--simer-primary);
		box-shadow: 0 8px 16px rgba(13, 31, 60, .12);
		z-index: 70;
	}
	.site-nav.is-open { display: block; }
	.primary-menu { flex-direction: column; padding: 10px; flex-wrap: nowrap; }
	.primary-menu a { padding: 12px 14px; }

	/* v1 / v3: keep relative so absolute dropdown anchors to header */
	.site-header--inline,
	.site-header--centered {
		position: sticky;
	}
	.site-header--inline .site-header-inner,
	.site-header--centered .site-header-inner {
		position: relative;
	}

	/* v2 bar: hide desktop nav row; open menu from brand row toggle */
	.site-header--bar .site-header-nav-row {
		display: none;
	}
	.site-header--bar .site-header-brand-row {
		position: relative;
	}
	.site-header--bar .site-nav {
		background: var(--header-menu-hover, var(--simer-primary));
	}
	.site-header--bar .primary-menu a {
		color: #fff;
	}
	/* When bar layout is open on mobile, show nav under brand row */
	.site-header--bar.is-nav-open .site-header-nav-row {
		display: block;
		position: absolute;
		top: 100%;
		left: 0;
		right: 0;
		z-index: 70;
		box-shadow: 0 8px 16px rgba(13, 31, 60, .12);
	}
	.site-header--bar.is-nav-open .site-header-nav-row .site-nav {
		display: block;
		position: static;
		border-bottom: 0;
		box-shadow: none;
	}
}

@media (max-width: 720px) {
	.speaker-card { flex-direction: column; }
	.speaker-avatar { width: 100%; height: auto; }
	.contact-card { flex-direction: column; }
	.hero-slide img { max-height: 300px; }
	.expert-cards { grid-template-columns: 1fr; }
}