/*
--- 01 TYPOGRAPHY SYSTEM

- Font sizes (px)
10 / 12 / 14 / 16 / 18 / 20 / 24 / 30 / 36 / 44 / 52 / 62 / 74 / 86 / 98

- Font weights
Default: 400
Medium: 500
Semi-bold: 600
Bold: 700

- Line heights
Default: 1
Small: 1.05
Medium: 1.2
Paragraph default: 1.6

- Letter spacing
-0.5px
0.75px

--- 02 COLORS

Blue,
icons-blue=> #4f8bcf
about-icon-color => #2b7a8a

Gray
icons-Gray=> #868f99


--- 05 SHADOWS



--- 06 BORDER-RADIUS

Default: 9px
Medium: 12px

--- 07 WHITESPACE

- Spacing system (px)
2 / 4 / 8 / 12 / 16 / 24 / 32 / 48 / 64 / 80 / 96 / 128

----08.footer,
     color-#d3d9ddff;

---09.nav,
     color- #d3d9ddff
    
--10.desc,
     color-rgba(48, 66, 92, 0.91);
--SubHeader,
     color-rgba(30, 64, 111, 0.91);
--- button color,
   - rgba(40, 87, 152, 0.91);
   -hover- rgba(31, 63, 108, 0.91);

*/

/* ************************************ */
/*          General Styles              */
/* ************************************ */
html {
  font-size: 62.5%;
  scroll-behavior: smooth;
   height: 100%;
}

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

body {
  font-family: sans-serif;
  line-height: 1;
  font-weight: 400;
  color: rgba(48, 66, 92, 0.91);
  height: 100%;

  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

main {
  flex: 1 0 auto;
}



/* ************************************************** */
/*             reveal section style                   */
/* ************************************************** */

/* Hidden by default */
.page {
  opacity: 0;
  transform: translateY(50px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

/* Visible state */
.page.reveal {
  opacity: 1;
  transform: translateY(0);
}

/* Generic reveal utility for elements */
.reveal-item{
  opacity: 0;
  transform: translateY(24px) scale(.995);
  transition: opacity 0.6s ease, transform 0.6s cubic-bezier(.2,.9,.25,1);
  transition-delay: var(--reveal-delay, 0s);
  will-change: opacity, transform;
}
.reveal-item.revealed{
  opacity: 1;
  transform: none;
}

/* Group helper: when a container has data-reveal-group, children with [data-reveal-child]
   will be staggered using --reveal-delay set by JS. */
.reveal-fade{
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  transition-delay: var(--reveal-delay,0s);
}
.reveal-fade.revealed{ opacity:1; transform:none; }

/* Optional: staggered children animation */
.page .fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.page.reveal .fade-in {
  opacity: 1;
  transform: translateY(0);
}




/* ******************************************
              NAVIGATION SECTION
*********************************************/

.header {
  background-color: transparent; 
  box-shadow: none; 
  display: flex;
  align-items: center;
  justify-content: space-between;

  height: 9.6rem;
  padding: 0 4.8rem 0  2rem;
  position:relative;
}

.btn-mobile-nav {
  display: none;
}

.escal {
  height: 7rem;
}


.main-nav-list {
  display: flex;
  list-style: none;
  gap: 3.2rem;
  align-items: center;
}


.main-nav-link:link,
.main-nav-link:visited {
  display: inline-block;
  text-decoration: none;
  color:  rgba(192, 221, 249);
  font-weight: 600;
  font-size: 2rem;
  transition: all 0.3s;
  cursor: pointer;
  position: relative;
  z-index: 10;
}

.main-nav-link:hover,
.main-nav-link:active {
  color:  #4c6078ff;
}

/* When header becomes sticky */
.sticky {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  transition: all 0.3s ease;
  animation: fadeSlideDown 0.4s ease forwards;
}

/* Shrink logo and height when sticky */
.sticky .escal {
  transform: scale(0.85);
  transition: transform 0.3s ease;
}

.sticky .main-nav-link {
  color: rgba(72, 148, 207, 0.8);
}

/* Animation for smooth fade and slide-down */
@keyframes fadeSlideDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}


/* === Animated Nav Indicator === */
.nav-indicator {
  position: absolute;
  bottom: 0;
  height: 3px;
  width: 0;
  background-color: rgba(40, 87, 152, 0.91);
  border-radius: 3px;
  transition: all 0.3s ease;
  transform-origin: left;
  z-index: 99;
  opacity: 0; 
}

/* Position inside header properly */
.main-nav {
  position: relative;
}

/* Active link color */
.main-nav-link.active {
  color:  rgba(40, 87, 152, 0.91);
  font-weight: 700;
}





/* **********************************
            footer 
*********************************** */
.footer{
    padding:6rem 0 3rem 0; 
    border-top: 1px solid rgba(184, 188, 193, 0.2);
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: #b8bcc1;
}

.footer-grid{
    display:grid;
    grid-template-columns:1.5fr 1.5fr 1fr 1fr 1fr;
    column-gap: 3rem;
    row-gap: 4rem;
    align-items:start;
}

.footer-logo {
  display: block;
  margin-bottom: 3.2rem;
}

.footer-desc{
    margin-bottom:4rem;
    font-size:1.6rem;
    line-height:1.8;
}

.social-links {
  list-style: none;
  display: flex;
  gap: 2.4rem;
  margin-bottom: 2.8rem;
}

.social-icon {
  height: 3rem;
  width: 3rem;
  transition: transform 0.3s ease, color 0.3s ease;
}

.social-icon:hover {
  transform: scale(1.2);
  color: #87cbe4;
}

.footer-heading {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 2rem;
  color: #87cbe4;
  border-left: 4px solid #87cbe4;
  padding-left: 0.6rem;
}

.footer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.footer-link,
.footer-link:link,
.footer-link:visited {
  text-decoration: none;
  font-size: 1.6rem;
  color: #b8bcc1;
  transition: all 0.3s ease;
}

.footer-link:hover,
.footer-link:active {
  color: #87cbe4;
}

.address {
  margin-bottom: 2.4rem;
}

.contacts {
  font-style: normal;
  font-size: 1.6rem;
  line-height: 1.6;
}

.contact-icon {
  height: 1.8rem;
  weight:1.8rem;
  margin-right: 0.8rem;
  vertical-align: middle;
  display: inline-block;
}

.footer-line{
    text-align:center;
    border-top:1px solid  #375677ff;
    margin-top-2rem; 
    padding-top:2rem;

}

.copyright {
  font-size: 1.4rem;
  line-height: 1.6;
  color:rgba(171, 203, 246, 0.91);
}



/* **********************************
       subsection footer
*********************************** */

.subSection-footer {
  background-color: #9fa2a3ff;
  color: rgba(31, 47, 69, 0.91);
  text-align: center;
  padding: 2rem 0;
  font-size: 1.6rem;
  border-top: 3px solid #1e234fff;
  flex-shrink: 0;
}



/* **********************************
       header footer
*********************************** */
.subSection-header {
  color: #fff;
  padding: 6rem 0 3rem;
  text-align: center;
  border-radius: 0 0 2rem 2rem;
}

.subSection-header .back-link {
  display: inline-block;
  color: #5b7bbeff;
  text-decoration: none;
  font-size: 1.8rem;
  margin-bottom: 2rem;
  transition: opacity 0.3s;
}

.subSection-header .back-link:hover {
  opacity: 0.8;
}






/* **********************************
    h2 tag sub heading
*********************************** */
.subheading {
  color: rgba(30, 64, 111, 0.91);
  letter-spacing: -0.5px;
  font-weight: 700;

  font-size: 4.4rem;
  line-height: 1.2;
  margin-bottom: 4.8rem;
  border-bottom:1px solid rgba(30, 64, 111, 0.91);
}

/* **********************************
    h3 tag sub heading
*********************************** */

.inherheader{
  color: rgba(42, 76, 123, 0.91);
  letter-spacing: -0.5px;
  font-weight: 600;

  font-size: 3.6rem;
  line-height: 1.2;
  margin-bottom: 2rem;

}



/* ************************** 
    container alignment
************************** */

.container{
    max-width:120rem;
    margin:0 auto;
    padding:0 3.2rem;
}

/* ************************** 
    grid template
************************** */
.grid{
    display:grid;
    column-gap:6.4rem;
    row-gap:9.6rem;
    margin-bottom:9.6rem;
}

.grid:last-child{
    margin-bottom:0;
}

.grid--2--cols{
    grid-template-columns:repeat(2,1fr)
}

.grid--3--cols{
    grid-template-columns:repeat(3,1fr)
}

.grid--4--cols{
    grid-template-columns:repeat(4,1fr)
}

.grid--5--cols{
    grid-template-columns:repeat(5,1fr)
}



/* **********************************
    contributor and supervisors
*********************************** */

.main-contributors{
  display: grid;
  gap: 2.4rem;
  align-items: stretch; 
  grid-auto-rows: 1fr; 
}

.contributor{
  box-shadow: 0 3.2rem 6.4rem rgba(0, 0, 0, 0.06);
  border-radius:1.2rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  overflow:hidden;
  display: flex;
  flex-direction: column;
  height: 100%; /* allow inner content to stretch so we can anchor the button */
}

.contributor:hover {
  transform: translateY(-10px) scale(1.03);
  box-shadow: 0 4rem 8rem rgba(0, 0, 0, 0.12);
}

.contributor-img{
    width:100%;
    aspect-ratio: 4 / 3;
    height: auto; 
    display:block;
    object-fit: cover; 
    object-position: center center; 
    background-color: #f5f7fb; 
    -webkit-transform: translateZ(0);
}



.contributor-name{
    font-size:1.8rem;
    font-weight:600;
    line-height:1.5;
    text-align:center;
    margin-bottom:1.8rem;
}

.contributor-batch{
    font-size:1.4rem;
    font-weight:;
    text-align:center;
}

.contributor-text{
  padding:2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.8rem;
  flex: 1 1 auto; 
}

.profile-btn{
  display: inline-block;
  margin-top: auto; /* push to bottom of card */
  padding: 0.6rem 1.2rem;
  background: #2b7a8a;
  color: #fff;
  border-radius: 0.6rem;
  text-decoration: none;
  font-size: 1.4rem;
  text-align: center;
  transition: transform 0.12s ease, background 0.12s ease;
  width: 80%;
  max-width: 18rem;
}
.profile-btn.disabled{ background: #f0f0f0; color: #8a8a8a; cursor: not-allowed; }



/* **********************************
         icons and tags
*********************************** */

.link-icons{
  height:3.6rem;
  width: 3.6rem;
  display: inline-block;
  /* Improve rendering quality for SVG/raster icons */
  image-rendering: -webkit-optimize-contrast;
  image-rendering: crisp-edges;
}

.link-tags {
  display: inline-block;
  cursor: pointer;
  transition: all 0.3s ease;
}

.link-tags:hover {
  opacity: 0.8;
  transform: scale(1.05);
}




@media (min-width: 900px) {
  .contributor-img{ max-height: 28rem; }
}
@media (max-width: 720px) {
  .contributor-img{ aspect-ratio: 3 / 2; max-height: 18rem; }
}

@media (max-width: 720px) {
  .contributor-img{ height: 14rem; }
  .profile-btn{ width: 90%; }
}