/* ─────────────────────────────────────────────
   Abhi Faldu — Portfolio
   Brand accent matches CV: #1a5276
───────────────────────────────────────────── */

:root {
  --accent: #1a7fc4;
  --accent-deep: #1a5276;
  --accent-soft: #d6eaf8;

  --bg: #ffffff;
  --bg-alt: #f4f7fb;
  --surface: #ffffff;
  --border: #e4e9f0;

  --text: #12212e;
  --text-soft: #4a5b6b;
  --text-mute: #7a8a99;

  --shadow-sm: 0 1px 2px rgba(16, 33, 46, .06), 0 2px 8px rgba(16, 33, 46, .05);
  --shadow-md: 0 8px 30px rgba(16, 33, 46, .10);

  --radius: 16px;
  --radius-sm: 10px;
  --maxw: 1120px;
  --font: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
}

:root[data-theme="dark"] {
  --accent: #4aa8e8;
  --accent-deep: #7cc4f0;
  --accent-soft: #17324a;

  --bg: #0d1520;
  --bg-alt: #111c2b;
  --surface: #15212f;
  --border: #243447;

  --text: #eaf1f8;
  --text-soft: #a9bccd;
  --text-mute: #6f8296;

  --shadow-sm: 0 1px 2px rgba(0,0,0,.3), 0 2px 8px rgba(0,0,0,.25);
  --shadow-md: 0 10px 34px rgba(0,0,0,.45);
}

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

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  transition: background .3s ease, color .3s ease;
}

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

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

/* ───────────── NAV ───────────── */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: saturate(180%) blur(14px);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  border-bottom: 1px solid transparent;
  transition: border-color .3s, background .3s;
}
.nav.scrolled { border-color: var(--border); box-shadow: var(--shadow-sm); }
.nav__inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.nav__logo { font-weight: 800; font-size: 1.35rem; letter-spacing: -.02em; }
.nav__logo span { color: var(--accent); }
.nav__links { display: flex; gap: 30px; }
.nav__links a { font-size: .94rem; font-weight: 500; color: var(--text-soft); position: relative; transition: color .2s; }
.nav__links a:hover { color: var(--accent); }
.nav__links a::after {
  content: ""; position: absolute; left: 0; bottom: -6px; height: 2px; width: 0;
  background: var(--accent); transition: width .25s ease;
}
.nav__links a:hover::after { width: 100%; }
.nav__actions { display: flex; align-items: center; gap: 10px; }

.theme-toggle {
  display: grid; place-items: center; width: 40px; height: 40px;
  border: 1px solid var(--border); background: var(--surface);
  border-radius: 10px; color: var(--text-soft); cursor: pointer; transition: .2s;
}
.theme-toggle:hover { color: var(--accent); border-color: var(--accent); }

.lang-toggle {
  display: inline-flex; align-items: center; gap: 6px; height: 40px; padding: 0 12px;
  border: 1px solid var(--border); background: var(--surface); border-radius: 10px;
  color: var(--text-soft); cursor: pointer; transition: .2s; font-weight: 600; font-size: .82rem;
}
.lang-toggle:hover { color: var(--accent); border-color: var(--accent); }
.lang-toggle #langCode { letter-spacing: .03em; }
.icon-moon { display: none; }
:root[data-theme="dark"] .icon-sun { display: none; }
:root[data-theme="dark"] .icon-moon { display: block; }

.nav__burger { display: none; flex-direction: column; gap: 5px; width: 40px; height: 40px;
  border: 1px solid var(--border); background: var(--surface); border-radius: 10px; cursor: pointer; align-items: center; justify-content: center; }
.nav__burger span { width: 18px; height: 2px; background: var(--text); transition: .3s; }
.nav__burger.open span:nth-child(1){ transform: translateY(7px) rotate(45deg); }
.nav__burger.open span:nth-child(2){ opacity: 0; }
.nav__burger.open span:nth-child(3){ transform: translateY(-7px) rotate(-45deg); }

/* ───────────── BUTTONS ───────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 600; font-size: .95rem; padding: 12px 24px; border-radius: 12px;
  border: 1px solid transparent; cursor: pointer; transition: transform .15s ease, box-shadow .2s, background .2s, color .2s;
}
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: var(--accent-deep); color: #fff; box-shadow: var(--shadow-sm); }
:root[data-theme="dark"] .btn--primary { background: var(--accent); color: #071018; }
.btn--primary:hover { box-shadow: var(--shadow-md); }
.btn--ghost { background: transparent; border-color: var(--border); color: var(--text); }
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn--lg { padding: 16px 34px; font-size: 1.05rem; }
.btn--copy { gap: 10px; }
.btn--copy .ico-check { display: none; }
.btn--copy.copied { background: #1e8e5a; border-color: #1e8e5a; color: #fff; }
:root[data-theme="dark"] .btn--copy.copied { background: #2ecc71; border-color: #2ecc71; color: #071018; }
.btn--copy.copied .ico-copy { display: none; }
.btn--copy.copied .ico-check { display: inline; }

/* ───────────── HERO ───────────── */
.hero { padding: 72px 0 40px; position: relative; }
.hero::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background:
    radial-gradient(50rem 30rem at 78% -8%, color-mix(in srgb, var(--accent) 16%, transparent), transparent 60%),
    radial-gradient(40rem 26rem at 8% 20%, color-mix(in srgb, var(--accent-deep) 12%, transparent), transparent 55%);
}
.hero__inner { display: grid; grid-template-columns: 1.15fr .85fr; gap: 48px; align-items: center; }
.hero__eyebrow { color: var(--accent); font-weight: 600; font-size: .9rem; letter-spacing: .04em; text-transform: uppercase; margin-bottom: 18px; }
.hero__title { font-size: clamp(2.1rem, 5vw, 3.5rem); line-height: 1.08; letter-spacing: -.03em; font-weight: 800; }
.grad {
  background: linear-gradient(120deg, var(--accent-deep), var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
:root[data-theme="dark"] .grad { background: linear-gradient(120deg, var(--accent), var(--accent-deep)); -webkit-background-clip: text; background-clip: text; }
.hero__sub { color: var(--text-soft); font-size: 1.12rem; margin: 22px 0 30px; max-width: 34rem; }
.hero__cta { display: flex; gap: 14px; flex-wrap: wrap; }
.hero__socials { display: flex; gap: 8px; margin-top: 28px; }
.hero__socials a {
  display: grid; place-items: center; width: 44px; height: 44px; border-radius: 12px;
  border: 1px solid var(--border); background: var(--surface); color: var(--text-soft); transition: .2s;
}
.hero__socials a:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }

/* code card */
.hero__card { display: flex; justify-content: center; }
.code-card {
  width: 100%; max-width: 420px; border-radius: 16px; overflow: hidden;
  background: #0f1b29; border: 1px solid #223449; box-shadow: var(--shadow-md);
  font-family: var(--mono);
}
.code-card__bar { display: flex; align-items: center; gap: 7px; padding: 12px 16px; background: #0b1520; border-bottom: 1px solid #1c2c3d; }
.code-card__bar span { width: 11px; height: 11px; border-radius: 50%; }
.code-card__bar span:nth-child(1){ background:#ff5f56; } .code-card__bar span:nth-child(2){ background:#ffbd2e; } .code-card__bar span:nth-child(3){ background:#27c93f; }
.code-card__bar p { margin-left: auto; color: #5b7186; font-size: .78rem; }
.code-card pre { padding: 20px 18px; overflow-x: auto; }
.code-card code { font-size: .82rem; line-height: 1.75; color: #c9d6e3; white-space: pre; }
.c-key { color: #ff79c6; } .c-cls { color: #8be9fd; } .c-str { color: #f1fa8c; } .c-fn { color: #50fa7b; }

/* ───────────── STATS ───────────── */
.stats { padding: 12px 0 20px; }
.stats__grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.stat {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px 20px; text-align: center; box-shadow: var(--shadow-sm);
}
.stat__num { display: block; font-size: 2.1rem; font-weight: 800; letter-spacing: -.02em; color: var(--accent-deep); }
:root[data-theme="dark"] .stat__num { color: var(--accent); }
.stat__label { font-size: .86rem; color: var(--text-mute); }

/* ───────────── SECTIONS ───────────── */
.section { padding: 84px 0; }
.section--alt { background: var(--bg-alt); }
.section__kicker { color: var(--accent); font-family: var(--mono); font-size: .82rem; letter-spacing: .05em; margin-bottom: 10px; }
.section__title { font-size: clamp(1.7rem, 3.4vw, 2.5rem); letter-spacing: -.02em; font-weight: 800; margin-bottom: 40px; }

/* about */
.about__grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: 44px; align-items: start; }
.about__text p { color: var(--text-soft); margin-bottom: 16px; font-size: 1.04rem; }
.about__text strong { color: var(--text); }
.about__facts { display: grid; gap: 14px; }
.fact {
  display: flex; gap: 14px; align-items: center; background: var(--surface);
  border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 16px 18px; box-shadow: var(--shadow-sm);
}
.fact span { font-size: 1.5rem; }
.fact strong { display: block; font-size: .98rem; }
.fact p { color: var(--text-mute); font-size: .84rem; }

/* skills */
.skills__grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.skill-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px; box-shadow: var(--shadow-sm); transition: transform .2s, box-shadow .2s, border-color .2s;
}
.skill-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: color-mix(in srgb, var(--accent) 40%, var(--border)); }
.skill-card h3 { font-size: 1.05rem; margin-bottom: 16px; color: var(--accent-deep); }
:root[data-theme="dark"] .skill-card h3 { color: var(--accent); }
.tags { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; }
.tags li {
  font-size: .84rem; font-weight: 500; padding: 6px 13px; border-radius: 999px;
  background: var(--accent-soft); color: var(--accent-deep); border: 1px solid transparent;
}
:root[data-theme="dark"] .tags li { color: var(--accent-deep); background: color-mix(in srgb, var(--accent) 16%, transparent); }
.tags--sm li { font-size: .76rem; padding: 4px 10px; background: transparent; border-color: var(--border); color: var(--text-mute); }

/* projects */
.projects { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px; }
.project {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow-sm); display: flex; flex-direction: column;
  transition: transform .2s, box-shadow .2s, border-color .2s; position: relative; overflow: hidden;
}
.project::before {
  content:""; position:absolute; left:0; top:0; height:3px; width:100%;
  background: linear-gradient(90deg, var(--accent-deep), var(--accent)); transform: scaleX(0); transform-origin: left; transition: transform .3s ease;
}
.project:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); border-color: color-mix(in srgb, var(--accent) 40%, var(--border)); }
.project:hover::before { transform: scaleX(1); }
/* project architecture diagrams */
.project__diagram {
  margin-bottom: 18px; border: 1px solid var(--border); border-radius: 10px;
  padding: 14px 12px; background: color-mix(in srgb, var(--accent) 5%, var(--surface));
  overflow-x: auto;
}
.project__diagram svg { width: 100%; min-width: 300px; height: auto; display: block; }
.dg-node { fill: var(--accent-soft); stroke: var(--border); stroke-width: 1; }
.dg-hero { fill: var(--accent-deep); stroke: var(--accent-deep); }
:root[data-theme="dark"] .dg-hero { fill: var(--accent); stroke: var(--accent); }
.dg { text-anchor: middle; }
.dg-t1 { fill: var(--accent-deep); font-size: 12px; font-weight: 600; }
.dg-t2 { fill: var(--text-mute); font-size: 9.5px; font-weight: 500; }
.dg-hero-t1 { fill: #fff; font-size: 12px; font-weight: 600; }
.dg-hero-t2 { fill: rgba(255,255,255,.82); font-size: 9.5px; font-weight: 500; }
:root[data-theme="dark"] .dg-hero-t1 { fill: #071018; }
:root[data-theme="dark"] .dg-hero-t2 { fill: rgba(7,16,24,.75); }
.dg-arrow { stroke: var(--text-mute); stroke-width: 1.5; fill: none; }
.dg-arrow-head { fill: var(--text-mute); }

.project__head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; margin-bottom: 12px; }
.project__head h3 { font-size: 1.16rem; letter-spacing: -.01em; }
.project__date { font-family: var(--mono); font-size: .74rem; color: var(--text-mute); white-space: nowrap; }
.project__desc { color: var(--text-soft); font-size: .96rem; margin-bottom: 14px; }
.project__points { list-style: none; display: grid; gap: 8px; margin-bottom: 16px; }
.project__points li { position: relative; padding-left: 20px; font-size: .92rem; color: var(--text-soft); }
.project__points li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }
.project__points strong { color: var(--text); }
.project .tags--sm { margin-bottom: 18px; }
.project__link { margin-top: auto; font-weight: 600; font-size: .92rem; color: var(--accent); transition: gap .2s; }
.project__link:hover { text-decoration: underline; }
.projects__more { text-align: center; margin-top: 34px; }

/* timeline */
.timeline { position: relative; max-width: 780px; }
.timeline::before { content:""; position:absolute; left: 7px; top: 6px; bottom: 6px; width: 2px; background: var(--border); }
.tl-item { position: relative; padding-left: 40px; padding-bottom: 34px; }
.tl-item:last-child { padding-bottom: 0; }
.tl-dot { position: absolute; left: 0; top: 6px; width: 16px; height: 16px; border-radius: 50%; background: var(--accent); border: 3px solid var(--bg-alt); box-shadow: 0 0 0 2px var(--accent); }
.tl-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; flex-wrap: wrap; }
.tl-head h3 { font-size: 1.1rem; }
.tl-head span { font-family: var(--mono); font-size: .76rem; color: var(--text-mute); }
.tl-place { color: var(--accent); font-weight: 500; font-size: .9rem; margin: 2px 0 6px; }
.tl-body p:last-child { color: var(--text-soft); font-size: .95rem; }

/* contact */
.contact { text-align: center; }
.contact__inner { display: flex; flex-direction: column; align-items: center; }
.contact__lead { color: var(--text-soft); font-size: 1.1rem; max-width: 38rem; margin-bottom: 28px; }
.contact__lead strong { color: var(--text); }
.contact__socials { display: flex; gap: 24px; margin-top: 26px; }
.contact__socials a { color: var(--text-soft); font-weight: 500; position: relative; transition: color .2s; }
.contact__socials a:hover { color: var(--accent); }

/* footer */
.footer { border-top: 1px solid var(--border); padding: 30px 0; background: var(--bg-alt); }
.footer__inner { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
.footer p { color: var(--text-mute); font-size: .88rem; }

/* reveal animation */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ───────────── RESPONSIVE ───────────── */
@media (max-width: 900px) {
  .hero__inner { grid-template-columns: 1fr; }
  .hero__card { order: -1; justify-content: flex-start; }
  .stats__grid { grid-template-columns: repeat(2, 1fr); }
  .about__grid, .skills__grid, .projects { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .nav__links {
    position: fixed; inset: 68px 0 auto 0; flex-direction: column; gap: 0;
    background: var(--bg); border-bottom: 1px solid var(--border);
    padding: 8px 24px 20px; transform: translateY(-120%); transition: transform .3s ease; box-shadow: var(--shadow-md);
  }
  .nav__links.open { transform: translateY(0); }
  .nav__links a { padding: 12px 0; border-bottom: 1px solid var(--border); }
  .nav__burger { display: flex; }
  .stats__grid { grid-template-columns: 1fr 1fr; }
  .section { padding: 60px 0; }
  .footer__inner { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; }
  .reveal { opacity: 1; transform: none; transition: none; }
}