/* ================================================
   Cecilia Y. Sui — Academic Website
   Custom CSS
   ================================================ */

:root {
  --navy:       #1d3557;
  --steel:      #457b9d;
  --text:       #2c2c2c;
  --muted:      #6c757d;
  --border:     #dee2e6;
  --bg-light:   #f8f9fa;
  --white:      #ffffff;
}

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

body {
  font-family: 'Open Sans', sans-serif;
  font-size: 16px;
  color: var(--text);
  line-height: 1.75;
  background: var(--white);
}

h1, h2, h3, h4, h5 {
  font-family: 'Lora', serif;
  color: var(--navy);
}

a {
  color: var(--steel);
  text-decoration: none;
}

a:hover {
  color: var(--navy);
  text-decoration: underline;
}

/* ===== NAVBAR ===== */
#mainNav {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  padding: 0.85rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
}

#mainNav .navbar-brand {
  font-family: 'Lora', serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--navy) !important;
  letter-spacing: 0.02em;
}

#mainNav .navbar-brand:hover {
  text-decoration: none;
}

#mainNav .nav-link {
  font-family: 'Open Sans', sans-serif;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted) !important;
  padding: 0.4rem 0.9rem !important;
  transition: color 0.2s ease;
}

#mainNav .nav-link:hover,
#mainNav .nav-link.active {
  color: var(--navy) !important;
  text-decoration: none;
}

#mainNav .navbar-toggler {
  border: 1px solid var(--border);
  font-size: 0.8rem;
  padding: 0.4rem 0.75rem;
  color: var(--muted);
}

#mainNav .navbar-toggler:focus {
  box-shadow: none;
}

/* ===== PAGE HEADER ===== */
.page-header {
  padding: 3.5rem 0 2.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 3rem;
}

.page-header h1 {
  font-size: 2.4rem;
  margin-bottom: 0.3rem;
  font-weight: 700;
}

.page-header .subheading {
  color: var(--muted);
  font-size: 0.95rem;
  font-style: italic;
}

/* ===== HOME — PROFILE SECTION ===== */
.profile-section {
  padding: 4rem 0 3rem;
}

.profile-card {
  text-align: center;
  padding-right: 2.5rem;
  border-right: 1px solid var(--border);
}

@media (max-width: 767px) {
  .profile-card {
    padding-right: 0;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding-bottom: 2rem;
    margin-bottom: 2rem;
  }
}

.profile-photo {
  width: 170px;
  height: 210px;
  object-fit: cover;
  object-position: center top;
  border-radius: 4px;
  margin-bottom: 1.25rem;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
  display: block;
  margin-left: auto;
  margin-right: auto;
}

.profile-card .profile-name {
  font-family: 'Lora', serif;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 0.2rem;
}

.profile-card .profile-title {
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.profile-links {
  list-style: none;
  padding: 0;
  margin: 0;
  text-align: left;
  display: inline-block;
}

.profile-links li {
  margin-bottom: 0.55rem;
}

.profile-links a {
  font-size: 0.82rem;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 0.55rem;
  transition: color 0.2s;
}

.profile-links a:hover {
  color: var(--steel);
  text-decoration: none;
}

.profile-links i {
  width: 15px;
  text-align: center;
  color: var(--steel);
  flex-shrink: 0;
}

/* ===== HOME — BIO SECTION ===== */
.bio-section {
  padding-left: 3rem;
}

@media (max-width: 767px) {
  .bio-section {
    padding-left: 0;
  }
}

.bio-section h1 {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 0.15rem;
}

.bio-section .subtitle {
  color: var(--steel);
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 1.75rem;
  letter-spacing: 0.02em;
}

.bio-text p {
  font-size: 0.95rem;
  line-height: 1.8;
  margin-bottom: 1rem;
}

.research-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.75rem;
}

.research-tag {
  background: var(--bg-light);
  color: var(--navy);
  border: 1px solid var(--border);
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.03em;
}

/* ===== SECTION HEADINGS (Research / Teaching) ===== */
.section-title {
  font-family: 'Lora', serif;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--navy);
  margin-top: 2.75rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--navy);
}

.section-title:first-of-type {
  margin-top: 0;
}

/* ===== RESEARCH — PAPER LIST ===== */
.paper-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.paper-item {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--border);
}

.paper-item:last-child {
  border-bottom: none;
}

.paper-title {
  font-family: 'Lora', serif;
  font-size: 0.975rem;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 0.3rem;
  line-height: 1.5;
}

.paper-title a {
  color: var(--navy);
}

.paper-title a:hover {
  color: var(--steel);
}

.paper-authors {
  font-size: 0.865rem;
  color: var(--text);
  margin-bottom: 0.4rem;
}

.paper-status {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.18rem 0.65rem;
  border-radius: 3px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.status-accepted {
  background: #d8f3dc;
  color: #1b4332;
}

.status-review {
  background: #dde8f0;
  color: #1d3557;
}

.status-progress {
  background: var(--bg-light);
  color: var(--muted);
  border: 1px solid var(--border);
}

/* ===== TEACHING — COURSE LIST ===== */
.course-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.course-item {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  padding: 0.9rem 0;
  border-bottom: 1px solid var(--border);
}

.course-item:last-child {
  border-bottom: none;
}

.course-name {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 0.1rem;
}

.course-name a {
  color: var(--text);
}

.course-name a:hover {
  color: var(--steel);
}

.course-meta {
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.5;
}

.course-date {
  font-size: 0.8rem;
  color: var(--muted);
  white-space: nowrap;
  flex-shrink: 0;
}

/* ===== CONTACT PAGE ===== */
.contact-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.contact-list li {
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}

.contact-list li:last-child {
  border-bottom: none;
}

.contact-list .contact-icon {
  color: var(--steel);
  font-size: 1rem;
  margin-top: 0.15rem;
  flex-shrink: 0;
  width: 20px;
  text-align: center;
}

.contact-label {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--navy);
  margin-bottom: 0.2rem;
}

.contact-value {
  color: var(--text);
  line-height: 1.6;
}

/* ===== CV PAGE ===== */
.cv-section {
  padding: 3rem 0;
}

.cv-download-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--navy);
  color: var(--white) !important;
  padding: 0.7rem 1.75rem;
  border-radius: 4px;
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  transition: background 0.2s ease;
  text-decoration: none !important;
  margin-bottom: 2.25rem;
}

.cv-download-btn:hover {
  background: var(--steel);
}

.cv-embed {
  width: 100%;
  height: 850px;
  border: 1px solid var(--border);
  border-radius: 4px;
}

/* ===== FOOTER ===== */
footer {
  margin-top: 5rem;
  padding: 1.75rem 0;
  border-top: 1px solid var(--border);
}

.footer-text {
  font-size: 0.78rem;
  color: var(--muted);
  text-align: center;
  margin: 0;
}