/* ============================================================
   PREETHI SIGHAVI — PORTFOLIO STYLESHEET
   Structure: Reset → Variables → Base → Layout → Nav →
              Hero → About → Experience → Projects →
              Skills → Contact → Footer → Animations → Media Queries
   ============================================================ */

/* ─── RESET ─── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* ─── CSS VARIABLES ─── */
:root {
  /* Colors */
  --bg:          #0a0a0f;
  --bg-alt:      #111118;
  --bg-card:     #1a1a24;
  --border:      rgba(255, 255, 255, 0.07);
  --border-hover:rgba(255, 255, 255, 0.13);
  --text:        #e8e8f0;
  --muted:       #8888a8;
  --accent:      #7c6af5;
  --accent-light:#a594f9;
  --accent-pale: #c4b5fd;
  --teal:        #2dd4bf;
  --green:       #4ade80;
  --coral:       #f87171;
  --amber:       #fbbf24;

  /* Typography */
  --font-display: 'Syne', sans-serif;
  --font-body:    'DM Sans', sans-serif;
  --font-mono:    'DM Mono', monospace;

  /* Spacing */
  --section-pad: 6rem 2rem;
  --container:   1100px;
  --nav-h:       72px;

  /* Radii */
  --r-sm: 6px;
  --r-md: 10px;
  --r-lg: 16px;
  --r-xl: 20px;

  /* Transitions */
  --t: 0.22s ease;
}

/* ─── BASE ─── */
html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

ul { list-style: none; }

strong { color: var(--text); font-weight: 500; }

img { max-width: 100%; display: block; }

/* ─── LAYOUT UTILITIES ─── */
.container {
  max-width: var(--container);
  margin: 0 auto;
  width: 100%;
}

.section {
  padding: var(--section-pad);
}

.section--alt {
  background: var(--bg-alt);
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-light);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 0.6rem;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.section-desc {
  color: var(--muted);
  max-width: 560px;
  line-height: 1.75;
  margin-bottom: 3rem;
}

/* ─── BUTTONS ─── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.8rem 1.75rem;
  border-radius: var(--r-md);
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.95rem;
  transition: all var(--t);
  cursor: pointer;
  border: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover {
  background: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(124, 106, 245, 0.28);
}

.btn-ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border-hover);
}
.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent-light);
  transform: translateY(-2px);
}

.btn-nav {
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 1.2rem;
  font-size: 0.82rem;
  border-radius: var(--r-sm);
}
.btn-nav:hover {
  background: var(--accent-light);
}

/* ─── NAVBAR ─── */
#navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--nav-h);
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  transition: background var(--t);
}

#navbar.scrolled {
  background: rgba(10, 10, 15, 0.96);
}

.nav-logo {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.3rem;
  letter-spacing: -0.02em;
  color: var(--text);
}
.nav-logo span { color: var(--accent-light); }

.nav-links {
  display: flex;
  gap: 2.25rem;
}

.nav-links a {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition: color var(--t);
  position: relative;
  padding-bottom: 2px;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--accent-light);
  transition: width var(--t);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--t);
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ─── HERO ─── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: calc(var(--nav-h) + 4rem) 2rem 5rem;
  position: relative;
  overflow: hidden;
}

.hero-grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 0%, black 0%, transparent 100%);
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
  filter: blur(80px);
}
.hero-glow--left {
  top: -15%;
  left: -10%;
  width: 55%;
  height: 70%;
  background: radial-gradient(ellipse, rgba(124, 106, 245, 0.09) 0%, transparent 70%);
}
.hero-glow--right {
  bottom: -10%;
  right: -5%;
  width: 45%;
  height: 60%;
  background: radial-gradient(ellipse, rgba(45, 212, 191, 0.06) 0%, transparent 70%);
}

.hero-inner {
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: rgba(124, 106, 245, 0.1);
  border: 1px solid rgba(124, 106, 245, 0.25);
  border-radius: 100px;
  padding: 0.35rem 1.1rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--accent-pale);
  margin-bottom: 1.75rem;
}

.badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--teal);
  flex-shrink: 0;
  animation: pulse 2s ease infinite;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 6.5vw, 5.2rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

.title-line {
  display: block;
}

.title-gradient {
  background: linear-gradient(135deg, var(--accent-light) 0%, var(--teal) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  max-width: 580px;
  font-size: 1.1rem;
  color: var(--muted);
  line-height: 1.75;
  margin-bottom: 2.5rem;
}

.hero-btns {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 4rem;
}

.hero-stats {
  display: flex;
  gap: 3.5rem;
  flex-wrap: wrap;
  padding-top: 3rem;
  border-top: 1px solid var(--border);
}

.stat-num {
  font-family: var(--font-display);
  font-size: 2.1rem;
  font-weight: 800;
  color: var(--text);
}

.stat-plus {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-light);
}

.stat-label {
  display: block;
  font-size: 0.78rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.07em;
  margin-top: 0.3rem;
}

/* ─── ABOUT ─── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
}

.about-text p {
  color: var(--muted);
  line-height: 1.8;
  margin-bottom: 1rem;
  font-size: 1.025rem;
}

.about-info {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-top: 2rem;
}

.about-info li {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 0.9rem;
  color: var(--muted);
}

.info-icon { font-size: 1rem; }

.about-info a {
  color: var(--muted);
  transition: color var(--t);
}
.about-info a:hover { color: var(--accent-light); }

/* Education Cards */
.edu-cards {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}

.edu-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  position: relative;
  overflow: hidden;
  transition: border-color var(--t), transform var(--t);
}

.edu-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--teal));
}

.edu-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.edu-card__inner {
  padding: 1.5rem 1.75rem;
}

.edu-degree {
  font-family: var(--font-display);
  font-size: 1.025rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0.3rem;
}

.edu-school {
  color: var(--accent-light);
  font-size: 0.875rem;
  margin-bottom: 0.3rem;
}

.edu-year {
  color: var(--muted);
  font-size: 0.8rem;
  font-family: var(--font-mono);
}

/* ─── EXPERIENCE ─── */
.timeline {
  position: relative;
  padding-left: 2.25rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.5rem;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--accent) 0%, transparent 100%);
}

.exp-item {
  position: relative;
  margin-bottom: 3.25rem;
  display: flex;
  gap: 0;
}

.exp-item:last-child { margin-bottom: 0; }

.exp-marker {
  position: absolute;
  left: -2.5rem;
  top: 0.4rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--bg), 0 0 0 4px var(--accent);
  flex-shrink: 0;
}

.exp-content { width: 100%; }

.exp-header { margin-bottom: 1rem; }

.exp-role {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0.2rem;
}

.exp-company {
  color: var(--accent-light);
  font-size: 0.875rem;
  margin-bottom: 0.25rem;
}

.exp-date {
  color: var(--muted);
  font-size: 0.78rem;
  font-family: var(--font-mono);
}

.exp-list {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.exp-list li {
  color: var(--muted);
  font-size: 0.925rem;
  line-height: 1.65;
  padding-left: 1.25rem;
  position: relative;
}

.exp-list li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--accent-light);
}

/* ─── PROJECTS ─── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  transition: border-color var(--t), transform var(--t), box-shadow var(--t);
  position: relative;
  overflow: hidden;
}

.project-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.project-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: 0 24px 48px rgba(0, 0, 0, 0.35);
}

.project-card:hover::after { opacity: 1; }

.project-badge {
  display: inline-block;
  background: rgba(124, 106, 245, 0.11);
  border: 1px solid rgba(124, 106, 245, 0.22);
  border-radius: 100px;
  padding: 0.22rem 0.8rem;
  font-size: 0.72rem;
  color: var(--accent-pale);
  font-family: var(--font-mono);
  margin-bottom: 1rem;
  width: fit-content;
}

.project-badge--teal {
  background: rgba(45, 212, 191, 0.1);
  border-color: rgba(45, 212, 191, 0.22);
  color: var(--teal);
}

.project-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0.75rem;
  line-height: 1.3;
}

.project-desc {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.65;
  margin-bottom: 1.25rem;
  flex: 1;
}

.project-metrics {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 1.1rem;
}

.metric {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  padding: 0.28rem 0.7rem;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--text);
}

.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-bottom: 1.25rem;
}

.tech {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.2rem 0.6rem;
  font-size: 0.73rem;
  color: var(--muted);
  font-family: var(--font-mono);
  transition: border-color var(--t), color var(--t);
}

.project-card:hover .tech {
  border-color: var(--border-hover);
}

.project-links {
  display: flex;
  gap: 1rem;
  margin-top: auto;
}

.project-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  color: var(--accent-light);
  font-size: 0.82rem;
  font-weight: 500;
  transition: color var(--t);
}

.project-link:hover { color: var(--accent-pale); }

.project-link svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

/* ─── SKILLS ─── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
}

.skill-group {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 1.5rem;
  transition: border-color var(--t), transform var(--t);
}

.skill-group:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.skill-group-title {
  font-family: var(--font-display);
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.55rem;
}

.skill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}
.skill-dot--purple { background: var(--accent-light); }
.skill-dot--teal   { background: var(--teal); }
.skill-dot--amber  { background: var(--amber); }
.skill-dot--green  { background: var(--green); }
.skill-dot--coral  { background: var(--coral); }

.skill-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.skill-pill {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  padding: 0.3rem 0.7rem;
  font-size: 0.8rem;
  color: var(--muted);
  transition: border-color var(--t), color var(--t), background var(--t);
  cursor: default;
}

.skill-pill:hover {
  border-color: var(--accent);
  color: var(--accent-pale);
  background: rgba(124, 106, 245, 0.08);
}

/* ─── CONTACT ─── */
.contact-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-xl);
  padding: 4rem 3.5rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.contact-glow {
  position: absolute;
  top: -50%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 300px;
  background: radial-gradient(ellipse, rgba(124, 106, 245, 0.07) 0%, transparent 70%);
  pointer-events: none;
}

.contact-title {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 3vw, 2.25rem);
  font-weight: 800;
  margin-bottom: 1rem;
}

.contact-sub {
  color: var(--muted);
  max-width: 500px;
  margin: 0 auto 2.5rem;
  line-height: 1.75;
}

.contact-btns {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

.contact-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.8rem 1.4rem;
  border: 1px solid var(--border-hover);
  border-radius: var(--r-md);
  color: var(--text);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--t);
  background: rgba(255, 255, 255, 0.02);
}

.contact-link:hover {
  border-color: var(--accent);
  color: var(--accent-light);
  background: rgba(124, 106, 245, 0.06);
  transform: translateY(-2px);
}

.contact-link svg {
  width: 17px;
  height: 17px;
  flex-shrink: 0;
}

/* ─── FOOTER ─── */
.footer {
  border-top: 1px solid var(--border);
  padding: 2rem;
  text-align: center;
}

.footer p {
  color: var(--muted);
  font-size: 0.82rem;
}

.footer span { color: var(--accent-light); }

/* ─── SCROLL TO TOP ─── */
#scroll-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 999;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  color: #fff;
  font-size: 1.1rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--t), transform var(--t), background var(--t);
}

#scroll-top.visible {
  opacity: 1;
  pointer-events: all;
}

#scroll-top:hover {
  background: var(--accent-light);
  transform: translateY(-3px);
}

/* ─── ANIMATIONS ─── */
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%       { opacity: 0.45; transform: scale(0.75); }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(28px); }
  to   { opacity: 1; transform: translateY(0); }
}

.fade-in {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ─── MEDIA QUERIES ─── */
@media (max-width: 900px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .hero-stats {
    gap: 2rem;
  }
}

@media (max-width: 768px) {
  :root { --nav-h: 64px; }

  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: rgba(10, 10, 15, 0.97);
    flex-direction: column;
    gap: 0;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border);
    transform: translateY(-110%);
    transition: transform 0.3s ease;
    backdrop-filter: blur(14px);
  }

  .nav-links.open { transform: translateY(0); }

  .nav-links li { width: 100%; }

  .nav-links a {
    display: block;
    padding: 0.9rem 2rem;
    font-size: 0.9rem;
  }

  .nav-links a::after { display: none; }

  .btn-nav { display: none; }

  .nav-toggle { display: flex; }

  .contact-card {
    padding: 2.5rem 1.5rem;
  }

  .hero-stats {
    gap: 1.5rem;
  }

  .stat-num { font-size: 1.65rem; }
}

@media (max-width: 480px) {
  .section { padding: 4rem 1.25rem; }
  .hero { padding: calc(var(--nav-h) + 3rem) 1.25rem 4rem; }
  .hero-btns { flex-direction: column; }
  .hero-btns .btn { width: 100%; justify-content: center; }
  .projects-grid { grid-template-columns: 1fr; }
  .skills-grid { grid-template-columns: 1fr; }
  .contact-btns { flex-direction: column; }
  .contact-btns .btn { width: 100%; justify-content: center; }
}