/* ── Reset ── */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: #f5f6f8;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 16px;
  line-height: 1.55;
  color: #333;
}
a { color: #1a73e8; text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── Container ── */
.container {
  margin: 0 auto;
  padding: 0 24px;
  max-width: 980px;
}

/* ── Header ── */
#dhead {
  background: #fff;
  border-bottom: 1px solid #e4e6ea;
  padding: 28px 0 22px;
}
#dhead-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 32px;
}
@media (max-width: 680px) {
  #dhead-inner { flex-direction: column; text-align: center; }
  #dico, #dbadges { justify-content: center; }
}

/* Profile photo — object-position ensures face is centred-top */
.ppic {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center 15%;
  border: 4px solid #fff;
  box-shadow: 0 4px 20px rgba(0,0,0,0.2);
  flex-shrink: 0;
}

h1 { font-size: 28px; font-weight: 700; color: #111; margin-bottom: 4px; }
h2 { font-size: 15px; font-weight: 500; color: #555; margin-bottom: 2px; }
h3 { font-size: 13.5px; font-weight: 400; color: #888; margin-bottom: 14px; }

/* Social icons — fixed square, no stretch */
#dico { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 10px; }
.iico {
  width: 34px; height: 34px;
  border-radius: 6px;
  object-fit: contain;
  opacity: 0.88;
  transition: opacity 0.18s, transform 0.18s;
  background: transparent;
  flex-shrink: 0;
}
.iico:hover { opacity: 1; transform: translateY(-2px); }

/* Badges */
#dbadges { display: flex; flex-wrap: wrap; gap: 6px; }
.badge {
  background: #eef2ff;
  color: #2a4bbd;
  border: 1px solid #c5d0f5;
  border-radius: 20px;
  padding: 3px 12px;
  font-size: 12px;
  font-weight: 500;
}
.badge-peng {
  background: #1a3a6b;
  color: #fff;
  border-color: #1a3a6b;
  font-weight: 700;
}

/* ── Tab bar ── */
#tab-bar {
  background: #fff;
  border-bottom: 3px solid #e4e6ea;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}
.tab-bar-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
}
.tab-btn {
  flex: 1;
  background: none;
  border: none;
  border-bottom: 4px solid transparent;
  margin-bottom: -3px;
  padding: 14px 10px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: background 0.15s, border-color 0.15s;
  text-align: left;
}
.tab-btn:hover { background: #f0f4ff; }
.tab-btn.active { border-bottom-color: #1a73e8; background: #f0f4ff; }
.tab-icon { font-size: 22px; flex-shrink: 0; }
.tab-label {
  font-size: 14px;
  font-weight: 600;
  color: #333;
  line-height: 1.3;
}
.tab-label small { font-size: 11.5px; font-weight: 400; color: #888; display: block; }
.tab-btn.active .tab-label { color: #1a73e8; }
@media (max-width: 560px) {
  .tab-icon { font-size: 18px; }
  .tab-label { font-size: 12px; }
  .tab-label small { display: none; }
  .tab-btn { padding: 12px 6px; }
}

/* ── No selection prompt — same width/padding as tab-bar-inner ── */
#no-selection {
  max-width: 980px;
  margin: 0 auto;
  padding: 60px 24px;
  text-align: center;
  color: #aaa;
  font-size: 17px;
}
.prompt-arrow {
  font-size: 48px;
  line-height: 1;
  margin-bottom: 12px;
  animation: bounce 1.4s ease-in-out infinite;
}
@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

/* ── Profile hero banners ── */
.profile-hero {
  padding: 36px 0 28px;
  margin-bottom: 0;
  color: #fff;
}
.ds-hero       { background: linear-gradient(135deg, #0d47a1 0%, #1565c0 50%, #1976d2 100%); }
.academic-hero { background: linear-gradient(135deg, #1b5e20 0%, #2e7d32 50%, #388e3c 100%); }
.ee-hero       { background: linear-gradient(135deg, #bf360c 0%, #d84315 50%, #e64a19 100%); }

.hero-title { font-size: 26px; font-weight: 700; margin-bottom: 6px; }
.hero-sub   { font-size: 14px; opacity: 0.88; margin-bottom: 24px; }

.hero-stats {
  display: flex;
  gap: 0;
  flex-wrap: wrap;
}
.stat {
  flex: 1;
  min-width: 110px;
  text-align: center;
  padding: 12px 8px;
  border-right: 1px solid rgba(255,255,255,0.25);
}
.stat:last-child { border-right: none; }
.stat-num { font-size: 22px; font-weight: 700; }
.stat-lbl { font-size: 11px; opacity: 0.8; text-transform: uppercase; letter-spacing: 0.04em; margin-top: 2px; }

/* P.Eng. stamp in EE hero */
.peng-stamp {
  display: inline-block;
  background: #fff;
  color: #bf360c;
  font-weight: 800;
  font-size: 15px;
  border-radius: 8px;
  padding: 4px 16px;
  margin-bottom: 12px;
  letter-spacing: 0.08em;
  border: 2px solid rgba(255,255,255,0.8);
}

/* ── Section content ── */
.profile-section > .container,
.profile-section > div.container { padding-top: 28px; padding-bottom: 4px; }

hr {
  border: none;
  height: 1px;
  background: #e4e6ea;
  margin: 8px 0;
}

.ctitle {
  font-size: 18px;
  font-weight: 700;
  color: #111;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid #e4e6ea;
}

/* ── About ── */
.about-text { font-size: 15px; color: #444; margin-bottom: 12px; max-width: 840px; }
.cv-link {
  display: inline-block;
  background: #1a73e8;
  color: #fff;
  padding: 9px 22px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: background 0.2s;
  margin-top: 4px;
}
.cv-link:hover { background: #1558c0; text-decoration: none; }

/* ── Research interest tags ── */
.interest-grid { display: flex; flex-wrap: wrap; gap: 8px; }
.interest-tag {
  background: #f0f4ff;
  color: #1a4bbd;
  border: 1px solid #c5d0f5;
  border-radius: 20px;
  padding: 5px 14px;
  font-size: 13px;
  font-weight: 500;
  white-space: nowrap;
}

/* ── Skills grid ── */
.skills-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px 28px; }
@media (max-width: 640px) { .skills-grid { grid-template-columns: 1fr; } }
.skill-group { border-left: 3px solid #1a73e8; padding-left: 12px; }
.skill-label { font-size: 12.5px; font-weight: 700; color: #1a3a6b; margin-bottom: 4px; text-transform: uppercase; letter-spacing: 0.03em; }
.skill-value { font-size: 13.5px; color: #555; line-height: 1.5; }

/* ── Impact tags ── */
.impact-tag {
  display: inline-block;
  background: #e8f5e9;
  color: #1b5e20;
  border-radius: 12px;
  padding: 2px 10px;
  font-size: 12px;
  font-weight: 600;
  margin: 0 4px 4px 0;
}

/* ── Timeline ── */
.row { display: grid; grid-template-columns: repeat(12, 1fr); }
.entry { margin-bottom: 4px; }
.timespan {
  grid-column: span 2;
  font-size: 12px;
  color: #999;
  text-align: right;
  padding-right: 12px;
  padding-top: 4px;
  white-space: nowrap;
}
.ico {
  grid-column: span 1;
  position: relative;
  border-left: 2px solid #dde0e6;
  padding-bottom: 8px;
}
.ico img {
  width: 44px; height: 44px;
  object-fit: contain;
  border-radius: 6px;
  margin-left: 10px;
  border: 1px solid #eee;
  background: #fff;
  padding: 2px;
}
.entry-dot {
  position: absolute;
  top: 5px; left: -7px;
  width: 10px; height: 10px;
  border-radius: 50%;
  background: #1a73e8;
  border: 2px solid #f5f6f8;
}
.desc {
  grid-column: span 9;
  font-size: 14.5px;
  color: #444;
  padding-left: 16px;
  padding-bottom: 24px;
  line-height: 1.65;
}
.desc strong { color: #111; font-size: 15px; }
@media (max-width: 768px) {
  .timespan { grid-column: span 12; text-align: left; padding-right: 0; font-size: 11px; color: #bbb; padding-bottom: 4px; }
  .ico      { grid-column: span 2; }
  .desc     { grid-column: span 10; }
}

/* ── Publications ── */
.pub-links { color: #888; font-size: 14px; margin-bottom: 20px; }
.pub-group-title {
  font-size: 13px; font-weight: 700;
  color: #1a3a6b;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin: 24px 0 10px;
  padding-bottom: 6px;
  border-bottom: 1px solid #e4e6ea;
}
.pub {
  border-left: 4px solid #1a73e8;
  padding: 8px 12px;
  margin-bottom: 10px;
  background: #fff;
  border-radius: 0 6px 6px 0;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}
.pub-status {
  display: inline-block;
  font-size: 10.5px; font-weight: 700;
  border-radius: 10px;
  padding: 1px 9px;
  margin-bottom: 5px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.published    { background: #e8f5e9; color: #2e7d32; }
.under-review { background: #fff8e1; color: #e65100; }
.accepted     { background: #e3f2fd; color: #0d47a1; }
.award-inline {
  display: inline-block;
  font-size: 10.5px; font-weight: 700;
  background: #fff3e0; color: #e65100;
  border-radius: 10px;
  padding: 1px 9px;
  margin-left: 6px;
}
.pub-title   { display: block; color: #111; font-size: 14px; font-weight: 600; margin-bottom: 3px; }
.pub-authors { display: block; color: #c0392b; font-size: 12.5px; margin-bottom: 2px; }
.pub-venue   { display: block; color: #2e7d32; font-size: 12.5px; }

/* ── Awards list ── */
.award-list { list-style: none; padding: 0; margin: 0; }
.award-list li {
  padding: 10px 0 10px 22px;
  border-bottom: 1px solid #f0f0f0;
  font-size: 14.5px;
  color: #444;
  position: relative;
}
.award-list li::before {
  content: "★";
  position: absolute; left: 0; top: 11px;
  color: #f4b400; font-size: 13px;
}
.award-list li strong { color: #111; }
.peng-highlight { color: #1a3a6b; font-weight: 800; font-size: 15px; }

/* ── Footer ── */
#footer {
  background: #fff;
  border-top: 1px solid #e4e6ea;
  margin-top: 40px;
  padding: 20px 24px 36px;
  text-align: center;
  color: #aaa;
  font-size: 13.5px;
}