:root {
  --bg: #0b0f14;
  --panel: #101621;
  --ink: #eaf2f8;
  --muted: #9fb2c4;
  --line: #223044;
  --brand: #7c9cff;
  --ring: rgba(124, 156, 255, 0.35);
  --radius: 14px;
}

* {
  box-sizing: border-box;
}
/* html, */
/* body {
  height: 100%;
} */
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 500 16px/1.55 ui-sans-serif, system-ui, -apple-system, Segoe UI, Inter,
    Roboto, Arial;
}

.site-header {
  max-width: 1000px;
  margin: 28px auto 8px;
  padding: 0 16px;
}
.site-header h1 {
  margin: 0 0 6px;
  font-size: 28px;
}
.subtitle {
  margin: 0;
  color: var(--muted);
}

.tabs {
  max-width: 1000px;
  margin: 10px auto;
  padding: 0 16px;
}

/* Radios are hidden; labels become the tabs */
.tab-radio {
  position: absolute;
  left: -9999px;
}

.tab-label {
  display: inline-block;
  margin: 8px 8px 0 0;
  padding: 10px 14px;
  border: 1px solid var(--line);
  background: var(--panel);
  border-radius: 999px;
  cursor: pointer;
  user-select: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease,
    transform 0.05s ease;
}
.tab-label:focus-visible {
  outline: none;
  box-shadow: 0 0 0 4px var(--ring);
}
.tab-label:hover {
  border-color: #2b3d55;
}

/* Panels */
.tab-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  margin-top: 12px;
  display: none; /* all hidden by default; radio selectors will show */
}

/* When a radio is checked, show its panel and style the label as active */
#tab-edu:checked ~ #label-edu,
#tab-exp:checked ~ #label-exp,
#tab-proj:checked ~ #label-proj,
#tab-tech:checked ~ #label-tech,
#tab-about:checked ~ #label-about {
  border-color: var(--brand);
  box-shadow: 0 0 0 4px var(--ring);
}

#tab-edu:checked ~ #panel-edu,
#tab-exp:checked ~ #panel-exp,
#tab-proj:checked ~ #panel-proj,
#tab-tech:checked ~ #panel-tech,
#tab-about:checked ~ #panel-about {
  display: block;
}

/* Cards */
.card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px;
  margin: 10px 0;
  transition: border-color 0.15s ease, background 0.15s ease;
}
.card:hover {
  border-color: #2a3b53;
  background: #0e1420;
}
.card-head {
  display: flex;
  gap: 10px;
  justify-content: space-between;
  flex-wrap: wrap;
  align-items: baseline;
}
.card h3 {
  margin: 0;
  font-size: 18px;
}
.when {
  color: var(--muted);
  font-size: 14px;
}
.lead {
  margin: 0.4rem 0 0.2rem;
}
.bullets {
  margin: 0.2rem 0 0.2rem 1.1rem;
}
.tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-top: 6px;
}
.tag {
  font-size: 12px;
  padding: 4px 8px;
  border: 1px solid #2a3b53;
  border-radius: 999px;
  color: #cfe4ff;
}

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}
.stack {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px;
}
.stack h4 {
  margin: 0.2rem 0 0.4rem;
}
.about {
  margin: 0;
  padding-top: 1rem;
}

.site-footer {
  max-width: 1000px;
  margin: 16px auto 32px;
  padding: 0 16px;
  color: var(--muted);
  text-align: center;
}

.pp-container {
  width: 14rem;
  height: 14rem;
  overflow: hidden;
  border-radius: 50%;
  margin-bottom: 12px;
  border: 3px solid var(--line);
}

.pp-container img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.header-flex {
  display: flex;
  align-items: center;
  gap: 24px; /* spacing between image and text */
  flex-wrap: wrap; /* stack vertically on small screens */
}

.header-text {
  flex: 1;
  min-width: 240px; /* prevent text squishing */
}

.header-text h1 {
  margin: 0 0 8px;
  font-size: 28px;
}

/* Make <a> tags with .tab-label class look like other tabs */
a.tab-label {
  text-decoration: none;
  color: var(--ink);
}

.thesis-tag a {
  display: block;
  color: inherit; /* Inherit color from parent .tag for consistency */
  text-decoration: none;
}

/* socials bar */
.socials {
  display: flex;
  justify-content: flex-end;
  gap: 16px;
  margin-bottom: 12px;
  position: fixed;
}

/* fixed socials bar - centered */
.socials-fixed {
  position: fixed;
  top: 0;
  left: 50%;
  transform: translateX(-50%); /* centers it horizontally */
  display: flex;
  gap: 16px;
  background: var(--panel);
  padding: 8px 20px;
  border-bottom-left-radius: 12px;
  border-bottom-right-radius: 12px;
  border: 1px solid var(--line);
  z-index: 1000;
}

.socials-fixed a,
.socials-fixed a:visited {
  color: var(--ink);
  font-weight: 600;
  text-decoration: none;
  padding: 4px 10px;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.socials-fixed a:hover {
  background: var(--brand);
  color: #fff;
}

.socials a,
.socials a:visited {
  color: var(--ink);
  font-weight: 600;
  text-decoration: none;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  transition: all 0.2s ease;
}

.socials a:hover {
  background: var(--brand);
  color: #fff;
  border-color: var(--brand);
}

.experience-image-container {
  width: 100%;
}

.experience-image-container img {
  width: 92%;
  /* border-radius: 12px; */
  margin-top: 12px;
}

/* Collapsible cards (details/summary) */
.collapsible {
  overflow: hidden; /* keeps rounded corners clean when collapsing */
  cursor: pointer;
}

.collapsible summary {
  position: relative;
  padding-left: 28px;       /* reserve space on the left */
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
}

/* Arrow positioned on the left */
.collapsible summary::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 50%;
  transform: translateY(-50%);
  width: 0;
  height: 0;
  border-left: 6px solid transparent;
  border-right: 6px solid transparent;
  border-top: 8px solid var(--muted); /* ▼ */
  transition: transform .15s ease;
  pointer-events: none;
}

/* Rotate to ▲ when open */
.collapsible[open] summary::before {
  transform: translateY(-50%) rotate(180deg);
}


.card-head h3 a {
    color: rgb(128, 96, 255); /* keep link color same as surrounding text */
    /* text-decoration: none; */
}
/* Small screens */
@media (max-width: 720px) {
  .grid {
    grid-template-columns: 1fr;
  }
}