/* ============================================================
   AI for Economic Research — shared stylesheet
   Base rules carried over from the course syllabus so every
   page reads as one system; component classes added below.
   ============================================================ */

body {
	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
	line-height: 1.7;
	background-color: #f8f9fa;
	color: #343a40;
	margin: 0;
	padding: 0;
}
.container {
	max-width: 950px;
	margin: 30px auto;
	padding: 30px 40px;
	background-color: #ffffff;
	border-radius: 12px;
	box-shadow: 0 6px 18px rgba(0,0,0,0.06);
}
h1 {
	font-size: 2.2em;
	color: #003366;
	border-bottom: 3px solid #0056b3;
	padding-bottom: 15px;
	margin-bottom: 20px;
	font-weight: 700;
}
h2 {
	font-size: 1.7em;
	color: #003366;
	border-bottom: 2px solid #e9ecef;
	padding-bottom: 10px;
	margin-top: 40px;
	margin-bottom: 20px;
	font-weight: 600;
}
h3 {
	font-size: 1.35em;
	color: #0056b3;
	margin-top: 25px;
	margin-bottom: 10px;
	font-weight: 600;
}
.instructor-info {
	background-color: #f8f9fa;
	border-left: 5px solid #0056b3;
	padding: 15px 25px;
	margin-bottom: 25px;
	border-radius: 0 8px 8px 0;
}
.instructor-info p { margin: 6px 0; font-size: 1.05em; }
.instructor-info a { color: #0056b3; text-decoration: none; font-weight: 500; }
.instructor-info a:hover { text-decoration: underline; }
p, li { font-size: 1.05em; margin-bottom: 8px; }
ul { list-style-type: none; padding-left: 25px; }
li { position: relative; padding-left: 20px; margin-bottom: 6px; }
li::before {
	content: '\2022';
	color: #0056b3;
	font-weight: bold;
	display: inline-block;
	width: 1em;
	margin-left: -20px;
	position: absolute;
	top: 0;
}
ul ul { margin-top: 6px; padding-left: 20px; }
ul ul li::before { content: '\2013'; color: #555; font-weight: normal; }
code {
	font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
	background-color: #e9ecef;
	padding: 2px 5px;
	border-radius: 4px;
	font-size: 0.93em;
}
.session-box {
	background-color: #fdfdfd;
	border: 1px solid #e0e0e0;
	border-left: 5px solid #0056b3;
	padding: 18px 22px;
	margin: 18px 0;
	border-radius: 0 8px 8px 0;
}
.session-box h3 { margin-top: 0; color: #003366; }
.session-meta { font-size: 0.95em; color: #555; margin-bottom: 10px; }
.lab-tag {
	display: inline-block;
	background-color: #fff3e0;
	border: 1px solid #ff9800;
	color: #e65100;
	padding: 2px 8px;
	border-radius: 4px;
	font-size: 0.85em;
	font-weight: 600;
}
.competency-box {
	background-color: #fdfdfd;
	border: 1px solid #e0e0e0;
	border-left: 5px solid #17a2b8;
	padding: 18px 22px;
	margin: 20px 0;
	border-radius: 0 8px 8px 0;
}
.competency-box h3 { margin-top: 0; color: #17a2b8; }
.ecosystem-box {
	background: linear-gradient(135deg, #f0f7ff 0%, #fff8f0 100%);
	border: 1px solid #ccd;
	border-left: 5px solid #003366;
	padding: 18px 24px;
	margin: 25px 0;
	border-radius: 0 8px 8px 0;
}
.ecosystem-box h3 { margin-top: 0; color: #003366; font-size: 1.15em; }
.ecosystem-box .eco-arrow { color: #0056b3; font-weight: 700; margin: 0 8px; }
.supp-box {
	background-color: #f0f7ff;
	border: 1px solid #b3d4fc;
	padding: 18px 22px;
	margin: 18px 0;
	border-radius: 8px;
}
.supp-box h3 { margin-top: 0; color: #003366; }
a { color: #0056b3; text-decoration: none; }
a:hover { text-decoration: underline; }
table {
	width: 100%;
	border-collapse: collapse;
	margin: 15px 0;
	font-size: 0.95em;
}
th, td { border: 1px solid #dee2e6; padding: 10px 12px; text-align: left; }
th { background-color: #f8f9fa; color: #003366; font-weight: 600; }
tr:nth-child(even) { background-color: #f8f9fa; }

/* ============================================================
   Component classes — landing / slides / labs pages
   ============================================================ */

/* Top navigation bar */
.topnav {
	display: flex;
	flex-wrap: wrap;
	gap: 8px 18px;
	align-items: center;
	font-size: 0.98em;
	margin: -6px 0 22px;
	padding-bottom: 14px;
	border-bottom: 1px solid #e9ecef;
}
.topnav a { font-weight: 600; }
.topnav .sep { color: #ced4da; }
.topnav .home { color: #003366; }

/* Quick-link buttons row on the landing page */
.quicklinks {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
	gap: 14px;
	margin: 24px 0 8px;
}
.quicklink {
	display: block;
	text-decoration: none;
	background: #fdfdfd;
	border: 1px solid #e0e0e0;
	border-left: 5px solid #0056b3;
	border-radius: 0 8px 8px 0;
	padding: 16px 20px;
	transition: box-shadow .15s, transform .15s;
}
.quicklink:hover { box-shadow: 0 4px 12px rgba(0,0,0,0.08); transform: translateY(-1px); text-decoration: none; }
.quicklink .ql-title { font-weight: 700; color: #003366; font-size: 1.1em; }
.quicklink .ql-sub { color: #666; font-size: 0.9em; }

/* Lecture card grid */
.lecture-grid {
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
	gap: 16px;
	margin: 18px 0;
}
.lecture-card {
	border: 1px solid #e0e0e0;
	border-radius: 8px;
	padding: 16px 18px;
	background: #fdfdfd;
}
.lecture-card .lec-num {
	font-size: 0.8em;
	font-weight: 700;
	color: #0056b3;
	letter-spacing: .05em;
	text-transform: uppercase;
}
.lecture-card .lec-title { font-weight: 600; color: #003366; margin: 2px 0 10px; display: block; }
.lecture-card .lec-links { font-size: 0.92em; }
.lecture-card .lec-links a { margin-right: 12px; }

/* Status badges */
.badge {
	display: inline-block;
	padding: 1px 8px;
	border-radius: 20px;
	font-size: 0.78em;
	font-weight: 600;
	vertical-align: middle;
}
.badge-ready { background: #e6f4ea; border: 1px solid #34a853; color: #137333; }
.badge-soon  { background: #f1f3f4; border: 1px solid #bdc1c6; color: #5f6368; }
.badge-lock  { background: #fff3e0; border: 1px solid #ff9800; color: #e65100; }

/* Codespaces / action button */
.btn {
	display: inline-block;
	background: #0056b3;
	color: #fff !important;
	padding: 9px 16px;
	border-radius: 6px;
	font-weight: 600;
	font-size: 0.95em;
	text-decoration: none;
}
.btn:hover { background: #003f86; text-decoration: none; }
.btn-ghost { background: #fff; color: #0056b3 !important; border: 1px solid #0056b3; }
.btn-ghost:hover { background: #f0f7ff; }

/* Download / resource list rows */
.res-row {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 10px 14px;
	padding: 12px 0;
	border-bottom: 1px solid #eee;
}
.res-row:last-child { border-bottom: none; }
.res-row .res-name { font-weight: 600; color: #003366; flex: 1; min-width: 200px; }

/* Callout / notice box */
.notice {
	background: #fff8e1;
	border: 1px solid #ffe082;
	border-left: 5px solid #ffb300;
	border-radius: 0 8px 8px 0;
	padding: 14px 20px;
	margin: 18px 0;
	font-size: 0.97em;
}
.notice.info { background: #f0f7ff; border-color: #b3d4fc; border-left-color: #0056b3; }

/* Footer */
.site-footer {
	max-width: 950px;
	margin: 0 auto 40px;
	padding: 18px 40px;
	color: #8a929a;
	font-size: 0.85em;
	text-align: center;
}

@media (max-width: 640px) {
	.container { margin: 12px; padding: 20px 18px; }
	h1 { font-size: 1.7em; }
}