/* ============================================================
   ARUNAKUMAR TAVVA — PORTFOLIO
   Yellow / Black / White Theme
   ============================================================ */

:root {
  --yellow:      #FFB700;
  --yellow-dark: #e0a200;
  --black:       #111111;
  --dark:        #1a1a1a;
  --white:       #ffffff;
  --gray-light:  #f8f8f8;
  --gray-mid:    #eeeeee;
  --gray:        #888888;
  --text:        #333333;
  --sidebar:     80px;
}

/* ---- Reset ---- */
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html  { scroll-behavior:smooth; }
body  { font-family:'Inter',sans-serif; color:var(--text); background:var(--white); overflow-x:hidden; }
a     { text-decoration:none; }
img   { max-width:100%; }

/* ============================================================
   SIDEBAR NAVIGATION
   ============================================================ */
.side-nav {
  position: fixed;
  left: 0; top: 0;
  width: var(--sidebar);
  height: 100vh;
  background: var(--black);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px 0;
  z-index: 1000;
  transition: transform .3s;
}

.nav-logo {
  width: 44px; height: 44px;
  background: var(--yellow);
  color: var(--black);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 16px;
  margin-bottom: 28px;
  flex-shrink: 0;
}

.nav-links {
  list-style: none;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: 100%;
  padding: 0 12px;
}

.nav-links li a {
  display: flex; align-items: center; justify-content: center;
  height: 44px;
  border-radius: 12px;
  color: #777;
  font-size: 16px;
  transition: background .25s, color .25s;
  position: relative;
}

.nav-links li a:hover,
.nav-links li a.active {
  background: var(--yellow);
  color: var(--black);
}

/* Tooltip */
.nav-links li a::after {
  content: attr(title);
  position: absolute;
  left: calc(var(--sidebar) - 4px);
  background: var(--yellow);
  color: var(--black);
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity .2s;
}
.nav-links li a:hover::after { opacity: 1; }

.nav-social {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 0 12px;
  width: 100%;
}
.nav-social a {
  display: flex; align-items: center; justify-content: center;
  height: 40px;
  border-radius: 10px;
  color: #666;
  font-size: 14px;
  border: 1px solid #333;
  transition: color .2s, border-color .2s;
}
.nav-social a:hover { color: var(--yellow); border-color: var(--yellow); }

/* Hamburger (mobile only) */
.hamburger {
  display: none;
  position: fixed;
  top: 14px; left: 14px;
  z-index: 1100;
  background: var(--yellow);
  color: var(--black);
  border: none;
  width: 44px; height: 44px;
  border-radius: 10px;
  font-size: 18px;
  cursor: pointer;
}

/* ============================================================
   MAIN CONTENT
   ============================================================ */
.main-content {
  margin-left: var(--sidebar);
  min-height: 100vh;
}

.section {
  min-height: 100vh;
  padding: 70px 60px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* ---- Section header shared ---- */
.section-header {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 44px;
}
.section-header.center {
  flex-direction: column;
  text-align: center;
  align-items: center;
}
.section-photo {
  width: 56px; height: 56px;
  border-radius: 50%;
  overflow: hidden;
  background: var(--gray-mid);
  flex-shrink: 0;
}
.section-photo img { width:100%; height:100%; object-fit:cover; }

.section-title {
  font-size: clamp(32px, 4vw, 52px);
  font-weight: 900;
  color: var(--black);
  letter-spacing: -1px;
  line-height: 1;
}
.section-subtitle { color: var(--gray); font-size: 15px; margin-top: 6px; }

/* ============================================================
   HERO
   ============================================================ */
.hero-section { background: var(--white); padding-top: 50px; }

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  max-width: 1200px;
}

.hero-greeting {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 4px;
  color: var(--gray);
  margin-bottom: 12px;
}
.hero-name {
  font-size: clamp(40px, 5vw, 68px);
  font-weight: 900;
  line-height: 1.05;
  color: var(--black);
  margin-bottom: 16px;
}
.highlight { color: var(--yellow); }

.hero-badge {
  display: inline-block;
  background: var(--yellow);
  color: var(--black);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 2px;
  padding: 6px 16px;
  border-radius: 4px;
  margin-bottom: 22px;
}

.hero-desc {
  font-size: 15px;
  line-height: 1.75;
  color: #555;
  max-width: 480px;
  margin-bottom: 32px;
}

.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 44px; }

.btn-primary {
  background: var(--yellow);
  color: var(--black);
  padding: 13px 28px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 1px;
  transition: background .25s, transform .25s, box-shadow .25s;
  display: inline-flex; align-items: center; gap: 8px;
  border: none; cursor: pointer;
}
.btn-primary:hover {
  background: var(--yellow-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(255,183,0,.35);
}
.btn-outline {
  background: transparent;
  color: var(--black);
  padding: 13px 28px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 1px;
  border: 2px solid var(--black);
  transition: background .25s, color .25s;
  display: inline-block;
}
.btn-outline:hover { background: var(--black); color: var(--white); }

.hero-stats { display: flex; gap: 32px; flex-wrap: wrap; }
.stat { display: flex; flex-direction: column; }
.stat-num { font-size: 28px; font-weight: 900; color: var(--black); line-height: 1; }
.stat-label { font-size: 10px; font-weight: 600; color: var(--gray); margin-top: 4px; text-transform: uppercase; letter-spacing: 1px; }

.hero-image { display: flex; flex-direction: column; align-items: center; gap: 14px; }

.image-frame {
  width: 100%;
  max-width: 420px;
  height: 480px;
  background: var(--gray-light);
  border-radius: 24px;
  overflow: hidden;
  position: relative;
}
.image-frame img { width:100%; height:100%; object-fit:cover; }

.image-placeholder {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: var(--gray);
  font-size: 13px;
  text-align: center;
  width: 100%; height: 100%;
}
.image-placeholder i { font-size: 64px; color: #ccc; }

.hero-image-badge {
  background: var(--yellow);
  color: var(--black);
  font-size: 13px;
  font-weight: 700;
  padding: 8px 20px;
  border-radius: 20px;
}

/* ============================================================
   ABOUT
   ============================================================ */
.about-section { background: var(--gray-light); }

.about-intro { margin-bottom: 36px; }
.about-intro > p:first-child { font-size: 18px; font-weight: 500; margin-bottom: 10px; }
.about-bio { color: #555; font-size: 15px; line-height: 1.75; max-width: 900px; }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4,1fr);
  gap: 16px;
  margin-bottom: 48px;
  max-width: 900px;
}
.stat-box {
  padding: 26px 20px;
  border-radius: 14px;
  text-align: center;
  display: flex; flex-direction: column; gap: 8px;
}
.stat-box.black { background: var(--black); color: var(--white); }
.stat-box.yellow { background: var(--yellow); color: var(--black); }
.big-num  { font-size: 38px; font-weight: 900; line-height: 1; }
.stat-desc { font-size: 10px; font-weight: 700; letter-spacing: 1.5px; opacity: .8; }

.about-open-to {
  margin-top: 20px;
  background: var(--yellow);
  color: var(--black);
  padding: 14px 20px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 500;
  display: flex;
  align-items: flex-start;
  gap: 10px;
  max-width: 900px;
}
.about-open-to i { margin-top: 2px; flex-shrink: 0; }
.about-open-to strong { font-weight: 700; }

.what-i-do h3, .skills-section h3 {
  font-size: 20px; font-weight: 700; color: var(--black); margin-bottom: 22px;
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(4,1fr);
  gap: 18px;
  margin-bottom: 48px;
}
.service-item {
  background: var(--white);
  padding: 24px;
  border-radius: 14px;
  border-top: 3px solid var(--yellow);
  transition: transform .25s, box-shadow .25s;
}
.service-item:hover { transform: translateY(-4px); box-shadow: 0 12px 30px rgba(0,0,0,.07); }
.service-item i  { font-size: 26px; color: var(--yellow); margin-bottom: 14px; display: block; }
.service-item h4 { font-size: 14px; font-weight: 700; color: var(--black); margin-bottom: 8px; }
.service-item p  { font-size: 13px; color: var(--gray); line-height: 1.6; }

.skills-tags { display: flex; flex-wrap: wrap; gap: 10px; }
.tag {
  background: var(--white);
  border: 1.5px solid #e0e0e0;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  transition: background .2s, border-color .2s, color .2s;
  cursor: default;
}
.tag:hover { background: var(--yellow); border-color: var(--yellow); color: var(--black); }

/* ============================================================
   RESUME
   ============================================================ */
.resume-section { background: var(--white); }

.resume-content {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 60px;
  max-width: 1100px;
}

.col-title {
  font-size: 17px; font-weight: 700; color: var(--black);
  margin-bottom: 22px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--yellow);
  display: flex; align-items: center; gap: 10px;
}
.col-title i { color: var(--yellow); }
.mt-40 { margin-top: 40px; }

.timeline-item {
  display: flex;
  gap: 14px;
  margin-bottom: 22px;
  position: relative;
}
.timeline-item::before {
  content: '';
  position: absolute;
  left: 7px; top: 18px; bottom: -22px;
  width: 2px;
  background: #e8e8e8;
}
.timeline-item:last-child::before { display: none; }

.timeline-dot {
  width: 16px; height: 16px;
  border-radius: 50%;
  background: #d0d0d0;
  flex-shrink: 0;
  margin-top: 3px;
}
.timeline-dot.yellow { background: var(--yellow); }

.gold-medal {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: linear-gradient(135deg, #f5a623, #f0c040);
  color: #5c3a00;
  font-size: 10px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 10px;
  margin-left: 6px;
  vertical-align: middle;
  letter-spacing: 0.5px;
}
.gold-medal i { font-size: 10px; }

.card-links-col { display: flex; flex-direction: column; gap: 6px; margin-top: 4px; }
.card-link-row {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  padding: 6px 10px;
  border-radius: 6px;
  background: var(--gray-light);
  transition: background .2s, color .2s;
}
.card-link-row:hover { background: var(--yellow); color: var(--black); }
.card-link-row i { font-size: 11px; width: 14px; flex-shrink: 0; }

.timeline-content h4    { font-size: 14px; font-weight: 700; color: var(--black); margin-bottom: 4px; }
.timeline-content .company { display:block; font-size:13px; color:var(--yellow-dark); font-weight:600; margin-bottom:2px; }
.timeline-content .period  { display:block; font-size:12px; color:var(--gray); margin-bottom:6px; }
.timeline-content p        { font-size:13px; color:#666; line-height:1.55; }

/* ============================================================
   PORTFOLIO
   ============================================================ */
.portfolio-section { background: var(--gray-light); }

.filter-tabs { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 38px; }
.filter-btn {
  background: transparent;
  border: 2px solid #ddd;
  padding: 8px 20px;
  border-radius: 25px;
  font-size: 12px; font-weight: 700; letter-spacing: 1px;
  cursor: pointer; color: var(--text);
  transition: background .25s, border-color .25s, color .25s;
  font-family: 'Inter', sans-serif;
}
.filter-btn.active, .filter-btn:hover {
  background: var(--yellow);
  border-color: var(--yellow);
  color: var(--black);
}

.portfolio-grid {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 22px;
  max-width: 1200px;
}

.portfolio-card {
  background: var(--white);
  border-radius: 16px;
  overflow: hidden;
  transition: transform .3s, box-shadow .3s, opacity .4s;
}
.portfolio-card:hover { transform: translateY(-6px); box-shadow: 0 20px 50px rgba(0,0,0,.1); }
.portfolio-card.hidden { display: none; }

.card-icon {
  height: 140px;
  display: flex; align-items: center; justify-content: center;
  font-size: 52px; color: white;
}
.bitebase-icon    { background: linear-gradient(135deg,#ff6b35,#ff8c42); }
.repwell-icon     { background: linear-gradient(135deg,#1565c0,#1976d2); }
.yallacarry-icon  { background: linear-gradient(135deg,#e65100,#ff6f00); }
.reachai-icon     { background: linear-gradient(135deg,#0077b5,#00a0dc); }
.signalhunt-icon  { background: linear-gradient(135deg,#2e7d32,#43a047); }
.railway-icon     { background: linear-gradient(135deg,#4a0080,#7b1fa2); }

.card-content { padding: 22px; }

.card-tag {
  display: inline-block;
  font-size: 11px; font-weight: 700;
  padding: 3px 10px;
  border-radius: 12px;
  margin-bottom: 10px;
  letter-spacing: .5px;
}
.card-tag.live        { background:#e8f5e9; color:#2e7d32; }
.card-tag.submitted   { background:#e3f2fd; color:#1565c0; }
.card-tag.in-progress { background:#fff3e0; color:#e65100; }
.card-tag.chrome-tag  { background:#f3e5f5; color:#6a1b9a; }
.card-tag.web-tag     { background:#e8eaf6; color:#283593; }

.card-content h3 { font-size: 20px; font-weight: 800; color: var(--black); margin-bottom: 8px; }
.card-content p  { font-size: 13px; color: #666; line-height: 1.6; margin-bottom: 14px; }

.card-tech { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.card-tech span {
  background: var(--gray-light);
  font-size: 11px; font-weight: 600;
  padding: 4px 10px;
  border-radius: 4px; color: #444;
}

.card-links { display: flex; gap: 10px; }
.card-btn {
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 12px; font-weight: 700;
  letter-spacing: .5px;
  transition: background .2s, color .2s, transform .2s;
}
.card-btn.primary { background: var(--yellow); color: var(--black); }
.card-btn.primary:hover { background: var(--yellow-dark); }
.card-btn.outline { border: 1.5px solid var(--black); color: var(--black); }
.card-btn.outline:hover { background: var(--black); color: var(--white); }

/* ============================================================
   BOOKS
   ============================================================ */
.books-section { background: var(--white); }

.books-grid {
  display: grid;
  grid-template-columns: repeat(4,1fr);
  gap: 24px;
  max-width: 1200px;
  margin: 0 auto;
}

.book-card { display: flex; flex-direction: column; gap: 16px; }

.book-cover {
  height: 220px;
  border-radius: 14px;
  overflow: hidden;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 4px 6px 24px rgba(0,0,0,.2);
  transition: transform .3s, box-shadow .3s;
}
.book-cover:hover { transform: translateY(-6px) rotate(1deg); box-shadow: 8px 14px 32px rgba(0,0,0,.28); }

.book-front { text-align: center; color: white; padding: 20px; }
.book-icon  { font-size: 34px; margin-bottom: 12px; display: block; }
.book-front h4 { font-size: 14px; font-weight: 800; line-height: 1.3; margin-bottom: 8px; }
.book-front span { font-size: 10px; opacity: .75; letter-spacing: 1px; }

.book-info h3 { font-size: 15px; font-weight: 700; color: var(--black); margin-bottom: 6px; }
.book-info p  { font-size: 13px; color: var(--gray); line-height: 1.5; margin-bottom: 12px; }

.book-btn {
  display: inline-flex; align-items: center; gap: 7px;
  background: #ff9900;
  color: var(--black);
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 12px; font-weight: 700;
  transition: background .2s, transform .2s;
}
.book-btn:hover { background: #e68900; transform: translateY(-2px); }

/* ============================================================
   NEW PORTFOLIO CARD COLOURS
   ============================================================ */
.costcanvas-icon  { background: linear-gradient(135deg,#0d47a1,#1565c0); }
.sprintpulse-icon { background: linear-gradient(135deg,#00695c,#00897b); }
.cybernexus-icon  { background: linear-gradient(135deg,#b71c1c,#c62828); }

/* ============================================================
   CONTACT
   ============================================================ */
.contact-section {
  background: var(--black);
  color: var(--white);
  justify-content: flex-start;
  padding-top: 80px;
}
.contact-section .section-title { color: var(--white); }
.contact-section .section-subtitle { color: #999; }

.contact-content {
  display: grid;
  grid-template-columns: 1fr 1.6fr;
  gap: 60px;
  max-width: 1100px;
  margin-bottom: 60px;
}

.contact-item { display: flex; align-items: flex-start; gap: 16px; margin-bottom: 28px; }
.contact-icon {
  width: 46px; height: 46px;
  background: var(--yellow);
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  color: var(--black); font-size: 18px;
  flex-shrink: 0;
}
.contact-item h4 { font-size: 11px; text-transform: uppercase; letter-spacing: 2px; color: #777; margin-bottom: 4px; }
.contact-item p  { font-size: 14px; color: var(--white); }

.contact-socials { display: flex; flex-direction: column; gap: 10px; margin-top: 8px; }
.social-btn {
  display: flex; align-items: center; gap: 10px;
  padding: 12px 16px;
  border-radius: 10px;
  font-size: 13px; font-weight: 600;
  transition: transform .2s, opacity .2s;
}
.social-btn:hover { transform: translateX(6px); opacity: .9; }
.social-btn.linkedin { background: #0077b5; color: white; }
.social-btn.github   { background: #2d2d2d; color: white; border: 1px solid #444; }
.social-btn.amazon   { background: #ff9900; color: var(--black); }
.social-btn.bitebase { background: #ff6b35; color: white; }

/* Contact form */
.contact-form {
  background: #1a1a1a;
  padding: 36px;
  border-radius: 16px;
}
.form-group { margin-bottom: 14px; }
.form-group input,
.form-group textarea {
  width: 100%;
  background: #222;
  border: 1.5px solid #333;
  border-radius: 8px;
  padding: 13px 16px;
  color: var(--white);
  font-size: 14px;
  font-family: 'Inter', sans-serif;
  outline: none;
  transition: border-color .2s;
}
.form-group input::placeholder,
.form-group textarea::placeholder { color: #555; }
.form-group input:focus,
.form-group textarea:focus { border-color: var(--yellow); }
.form-group textarea { resize: vertical; }

.btn-primary.full-width { width: 100%; justify-content: center; font-family: 'Inter', sans-serif; padding: 15px; font-size: 14px; }

/* Footer */
.footer {
  border-top: 1px solid #1e1e1e;
  padding-top: 28px;
  text-align: center;
  color: #555;
  font-size: 13px;
}
.footer p:first-child { margin-bottom: 8px; }
.footer .yellow { color: var(--yellow); }
.footer-tagline { font-weight: 700; font-size: 14px; color: #333; letter-spacing: 4px; }

/* ============================================================
   SCROLL ANIMATION
   ============================================================ */
.animate-card {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .55s ease, transform .55s ease;
}
.animate-card.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================================
   RESPONSIVE — TABLET
   ============================================================ */
@media (max-width: 1200px) {
  .books-grid      { grid-template-columns: repeat(2,1fr); }
  .portfolio-grid  { grid-template-columns: repeat(2,1fr); }
  .stats-grid      { grid-template-columns: repeat(2,1fr); }
  .services-grid   { grid-template-columns: repeat(2,1fr); }
}

@media (max-width: 960px) {
  :root { --sidebar: 64px; }
  .section         { padding: 50px 36px; }
  .hero-content    { grid-template-columns: 1fr; }
  .hero-image      { display: none; }
  .resume-content  { grid-template-columns: 1fr; }
  .contact-content { grid-template-columns: 1fr; }
}

/* ============================================================
   RESPONSIVE — MOBILE
   ============================================================ */
@media (max-width: 640px) {
  .hamburger   { display: flex; align-items: center; justify-content: center; }

  .side-nav {
    transform: translateX(-100%);
    width: 220px;
    box-shadow: 4px 0 20px rgba(0,0,0,.4);
  }
  .side-nav.open { transform: translateX(0); }

  .main-content  { margin-left: 0; }
  .section       { padding: 40px 20px; min-height: auto; }
  .section-title { font-size: 28px; }
  .hero-name     { font-size: 36px; }
  .hero-badge    { font-size: 9px; letter-spacing: 1px; }

  .books-grid     { grid-template-columns: 1fr 1fr; }
  .portfolio-grid { grid-template-columns: 1fr; }
  .stats-grid     { grid-template-columns: 1fr 1fr; }
  .services-grid  { grid-template-columns: 1fr; }

  .nav-links { padding: 0 16px; }
  .nav-links li a { justify-content: flex-start; padding-left: 14px; gap: 12px; font-size: 14px; }
  .nav-links li a::before {
    content: attr(title);
    font-size: 13px;
    font-weight: 600;
    color: inherit;
    order: 2;
  }
  .nav-links li a::after { display: none; }

  .contact-form { padding: 22px; }
}