/* =========================================================
   YATVIKIT — DATA SCIENCE with GenAI & Agentic Systems
   Design tokens
   ========================================================= */
@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;600;700&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root{
  /* ---- color ---- */
  --ink:        #0B1120;   /* near-black navy, headings */
  --ink-soft:   #45526B;   /* body copy */
  --ink-faint:  #8892A6;   /* captions/meta */
  --bg:         #F6F8FC;   /* page background */
  --surface:    #FFFFFF;   /* cards */
  --surface-alt:#EEF1F8;   /* subtle section fill */
  --line:       #E3E8F2;   /* hairlines */

  --brand-900:  #0B1120;
  --brand-800:  #121B3A;
  --brand-700:  #1B2559;
  --brand-600:  #2F3B8C;
  --brand-500:  #4F46E5;   /* primary indigo */
  --brand-400:  #6C63F5;

  --cyan-400:   #17C3D6;   /* AI / data accent */
  --cyan-300:   #5FE3EE;

  --amber-500:  #F5A524;   /* CTA / highlight */
  --amber-400:  #FFC257;

  --success:    #1FA37B;
  --error:      #E14B4B;

  /* ---- type ---- */
  --font-display: 'Space Grotesk', 'Inter', sans-serif;
  --font-body:    'Inter', sans-serif;
  --font-mono:    'JetBrains Mono', monospace;

  /* ---- layout ---- */
  --maxw: 1180px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --shadow-sm: 0 1px 2px rgba(11,17,32,.06), 0 1px 1px rgba(11,17,32,.04);
  --shadow-md: 0 10px 30px -12px rgba(15,23,60,.25);
  --shadow-lg: 0 24px 60px -20px rgba(15,23,60,.35);
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  font-family:var(--font-body);
  color:var(--ink-soft);
  background:var(--bg);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block;}
a{color:inherit;text-decoration:none;}
ul{margin:0;padding:0;list-style:none;}
h1,h2,h3,h4{
  font-family:var(--font-display);
  color:var(--ink);
  margin:0 0 .5em;
  line-height:1.15;
  letter-spacing:-.01em;
}
p{margin:0 0 1em;}
.container{max-width:var(--maxw);margin:0 auto;padding:0 24px;}
section{padding:96px 0;}
@media (max-width:768px){ section{padding:64px 0;} }

.eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.08em;
  text-transform:uppercase;
  color:var(--brand-500);
  background:rgba(79,70,229,.08);
  border:1px solid rgba(79,70,229,.18);
  padding:6px 14px;
  border-radius:99px;
  margin-bottom:18px;
}
.eyebrow::before{content:'';width:6px;height:6px;border-radius:50%;background:var(--amber-500);}

.section-head{max-width:680px;margin-bottom:48px;}
.section-head h2{font-size:clamp(28px,3.4vw,40px);}
.section-head p{font-size:17px;color:var(--ink-soft);}
.section-head.center{margin-left:auto;margin-right:auto;text-align:center;}

/* ---- buttons ---- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  font-family:var(--font-body);font-weight:600;font-size:15px;
  padding:13px 26px;border-radius:10px;border:1px solid transparent;
  cursor:pointer;transition:transform .15s ease, box-shadow .15s ease, background .15s ease;
  white-space:nowrap;
}
.btn-primary{background:var(--amber-500);color:var(--brand-900);box-shadow:var(--shadow-sm);}
.btn-primary:hover{background:var(--amber-400);transform:translateY(-2px);box-shadow:var(--shadow-md);}
.btn-outline{border-color:rgba(255,255,255,.35);color:#fff;}
.btn-outline:hover{background:rgba(255,255,255,.1);transform:translateY(-2px);}
.btn-ghost{border-color:var(--line);color:var(--brand-700);background:var(--surface);}
.btn-ghost:hover{border-color:var(--brand-500);color:var(--brand-500);}
.btn-block{width:100%;}
.btn[disabled]{opacity:.6;cursor:not-allowed;}

/* =========================================================
   NAVBAR
   ========================================================= */
.site-header{
  position:sticky;top:0;z-index:100;
  background:rgba(11,17,32,.86);
  backdrop-filter:blur(10px);
  border-bottom:1px solid rgba(255,255,255,.06);
}
.navbar{display:flex;align-items:center;justify-content:space-between;height:74px;}
.brand{display:flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:700;font-size:20px;color:#fff;}
.brand-mark{
  width:38px;height:38px;border-radius:10px;
  background:linear-gradient(135deg,var(--brand-500),var(--cyan-400));
  display:flex;align-items:center;justify-content:center;
  font-family:var(--font-display);font-weight:700;font-size:19px;color:#fff;
  box-shadow:0 6px 16px -4px rgba(79,70,229,.6);
}
.brand-name{letter-spacing:.01em;}
.brand-name b{color:var(--cyan-300);font-weight:700;}

.nav-links{display:flex;align-items:center;gap:6px;}
.nav-links a{
  color:rgba(255,255,255,.78);font-weight:500;font-size:15px;
  padding:10px 16px;border-radius:8px;transition:all .15s ease;
}
.nav-links a:hover{color:#fff;background:rgba(255,255,255,.08);}
.nav-links a.active{color:#fff;background:rgba(255,255,255,.1);}
.nav-cta{
  background:var(--amber-500);color:var(--brand-900) !important;
  font-weight:700;padding:10px 20px !important;margin-left:6px;
}
.nav-cta:hover{background:var(--amber-400);}

.nav-toggle{display:none;background:none;border:0;cursor:pointer;padding:8px;}
.nav-toggle span{display:block;width:22px;height:2px;background:#fff;margin:5px 0;border-radius:2px;transition:.2s;}

@media (max-width:900px){
  .nav-toggle{display:block;}
  .nav-links{
    position:fixed;inset:74px 0 0 0;height:calc(100vh - 74px);
    background:var(--brand-900);flex-direction:column;align-items:stretch;
    padding:20px;gap:4px;transform:translateX(100%);transition:transform .25s ease;
    overflow-y:auto;
  }
  .nav-links.open{transform:translateX(0);}
  .nav-links a{padding:16px 14px;font-size:17px;border-bottom:1px solid rgba(255,255,255,.06);}
  .nav-cta{margin-top:10px;text-align:center;}
}

/* =========================================================
   HERO
   ========================================================= */
.hero{
  position:relative;overflow:hidden;
  background:
    radial-gradient(900px 480px at 85% -10%, rgba(79,70,229,.55), transparent 60%),
    radial-gradient(700px 420px at 0% 110%, rgba(23,195,214,.35), transparent 60%),
    linear-gradient(180deg,var(--brand-900) 0%, var(--brand-800) 100%);
  padding:88px 0 0;
  color:#fff;
}
.hero-grid{
  display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center;
  padding-bottom:64px;
}
@media (max-width:980px){ .hero-grid{grid-template-columns:1fr;} }

.hero .eyebrow{background:rgba(255,255,255,.08);border-color:rgba(255,255,255,.18);color:var(--cyan-300);}
.hero h1{font-size:clamp(34px,5vw,54px);color:#fff;}
.hero h1 em{font-style:normal;background:linear-gradient(90deg,var(--cyan-300),var(--amber-400));-webkit-background-clip:text;background-clip:text;color:transparent;}
.hero-sub{font-size:17.5px;color:rgba(255,255,255,.72);max-width:520px;margin-bottom:32px;}
.hero-actions{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:44px;}

.hero-stats{display:flex;gap:32px;flex-wrap:wrap;}
.hero-stats div{display:flex;flex-direction:column;}
.hero-stats b{font-family:var(--font-display);font-size:26px;color:#fff;}
.hero-stats span{font-size:13px;color:rgba(255,255,255,.55);font-family:var(--font-mono);}

/* terminal signature panel */
.terminal{
  background:#0D1326;border:1px solid rgba(255,255,255,.09);
  border-radius:var(--radius-lg);box-shadow:var(--shadow-lg);
  overflow:hidden;
}
.terminal-bar{
  display:flex;align-items:center;gap:8px;padding:13px 16px;
  background:rgba(255,255,255,.04);border-bottom:1px solid rgba(255,255,255,.07);
}
.terminal-dot{width:11px;height:11px;border-radius:50%;}
.terminal-dot.r{background:#FF5F57;} .terminal-dot.y{background:#FEBC2E;} .terminal-dot.g{background:#28C840;}
.terminal-title{margin-left:8px;font-family:var(--font-mono);font-size:12.5px;color:rgba(255,255,255,.4);}
.terminal-body{padding:22px 22px 26px;font-family:var(--font-mono);font-size:14px;color:#C7D3F5;min-height:230px;}
.terminal-body .prompt{color:var(--cyan-300);}
.terminal-line{opacity:0;animation:reveal .4s forwards;white-space:pre-wrap;margin-bottom:10px;}
.cursor{display:inline-block;width:8px;height:15px;background:var(--amber-400);vertical-align:-2px;animation:blink 1s step-end infinite;}
@keyframes reveal{to{opacity:1;}}
@keyframes blink{50%{opacity:0;}}

.hero-strip{
  border-top:1px solid rgba(255,255,255,.08);
  padding:18px 0;background:rgba(255,255,255,.03);
}
.hero-strip .container{display:flex;gap:36px;flex-wrap:wrap;justify-content:center;align-items:center;}
.hero-strip span{font-family:var(--font-mono);font-size:12.5px;color:rgba(255,255,255,.5);letter-spacing:.04em;}

/* =========================================================
   PROGRAM / COURSE CARDS
   ========================================================= */
.programs-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px;}
@media (max-width:820px){ .programs-grid{grid-template-columns:1fr;} }

.program-card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-lg);
  padding:32px;box-shadow:var(--shadow-sm);transition:transform .18s ease, box-shadow .18s ease;
  display:flex;flex-direction:column;height:100%;
}
.program-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md);}
.program-card.featured{
  border:1.5px solid var(--brand-500);
  background:linear-gradient(180deg,#FFFFFF 0%, #F5F4FF 100%);
  position:relative;
}
.badge-featured{
  position:absolute;top:-13px;right:28px;background:var(--brand-500);color:#fff;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.06em;text-transform:uppercase;
  padding:6px 12px;border-radius:99px;box-shadow:var(--shadow-sm);
}
.program-card .p-duration{
  font-family:var(--font-mono);font-size:12.5px;color:var(--brand-500);
  text-transform:uppercase;letter-spacing:.06em;margin-bottom:10px;
}
.program-card h3{font-size:22px;margin-bottom:8px;}
.program-card .p-desc{font-size:14.5px;color:var(--ink-soft);margin-bottom:18px;}
.program-meta{display:flex;gap:18px;flex-wrap:wrap;font-size:13px;color:var(--ink-faint);margin-bottom:20px;padding-bottom:20px;border-bottom:1px dashed var(--line);}
.program-meta strong{color:var(--ink);}
.program-skills{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:24px;flex:1;}
.pill{
  font-size:12.5px;background:var(--surface-alt);color:var(--brand-700);
  padding:6px 12px;border-radius:99px;border:1px solid var(--line);
}
.program-card .btn{margin-top:auto;}

/* =========================================================
   PHASE TIMELINE (flagship curriculum)
   ========================================================= */
.phase-list{display:flex;flex-direction:column;gap:0;}
.phase-item{
  display:grid;grid-template-columns:96px 1fr;gap:28px;
  padding:30px 0;border-top:1px solid var(--line);
}
.phase-item:last-child{border-bottom:1px solid var(--line);}
.phase-num{font-family:var(--font-mono);font-size:14px;color:var(--brand-500);padding-top:4px;}
.phase-num b{display:block;font-family:var(--font-display);font-size:30px;color:var(--ink);line-height:1;margin-top:4px;}
.phase-content h4{font-size:19px;margin-bottom:6px;}
.phase-content .tagline{font-family:var(--font-mono);font-size:12.5px;color:var(--ink-faint);margin-bottom:14px;}
.phase-topics{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:14px;}
.phase-topics span{
  font-size:12.5px;background:var(--surface-alt);padding:5px 11px;border-radius:6px;color:var(--ink-soft);
}
.phase-build{
  font-size:14px;background:rgba(23,195,214,.07);border-left:3px solid var(--cyan-400);
  padding:12px 16px;border-radius:0 8px 8px 0;color:var(--ink-soft);
}
.phase-build b{color:var(--ink);}

@media (max-width:640px){
  .phase-item{grid-template-columns:1fr;gap:8px;}
  .phase-num{display:flex;align-items:baseline;gap:10px;}
  .phase-num b{margin-top:0;font-size:22px;}
}

/* =========================================================
   SKILLS / TOOLS
   ========================================================= */
.skills-cloud{display:flex;flex-wrap:wrap;gap:10px;}
.skill-chip{
  font-size:14px;font-weight:500;color:var(--brand-700);
  background:var(--surface);border:1px solid var(--line);
  padding:10px 16px;border-radius:10px;box-shadow:var(--shadow-sm);
}
.tools-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(130px,1fr));gap:12px;}
.tool-badge{
  background:var(--surface);border:1px solid var(--line);border-radius:12px;
  padding:16px 10px;text-align:center;font-family:var(--font-mono);font-size:12.5px;
  color:var(--ink-soft);box-shadow:var(--shadow-sm);
}

/* =========================================================
   ELIGIBILITY / PLACEMENT
   ========================================================= */
.two-col{display:grid;grid-template-columns:1fr 1fr;gap:28px;}
@media (max-width:820px){ .two-col{grid-template-columns:1fr;} }
.info-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md);padding:28px;}
.info-card h4{font-size:16px;font-family:var(--font-mono);text-transform:uppercase;letter-spacing:.05em;color:var(--brand-500);margin-bottom:16px;}
.check-list li{position:relative;padding-left:26px;margin-bottom:12px;font-size:14.5px;color:var(--ink-soft);}
.check-list li::before{
  content:'';position:absolute;left:0;top:5px;width:16px;height:16px;border-radius:50%;
  background:var(--cyan-400);
}
.check-list li::after{
  content:'';position:absolute;left:4.5px;top:8.5px;width:7px;height:4px;
  border-left:2px solid #fff;border-bottom:2px solid #fff;transform:rotate(-45deg);
}

/* =========================================================
   DARK CTA BAND
   ========================================================= */
.cta-band{
  background:linear-gradient(135deg,var(--brand-900),var(--brand-700));
  color:#fff;border-radius:var(--radius-lg);padding:56px;
  display:flex;justify-content:space-between;align-items:center;gap:32px;flex-wrap:wrap;
  position:relative;overflow:hidden;
}
.cta-band::after{
  content:'';position:absolute;inset:0;
  background:radial-gradient(420px 220px at 90% 20%, rgba(23,195,214,.35), transparent 70%);
}
.cta-band h3{color:#fff;font-size:26px;margin-bottom:6px;position:relative;}
.cta-band p{color:rgba(255,255,255,.68);margin:0;position:relative;}
.cta-band .btn{position:relative;}

/* =========================================================
   FOOTER
   ========================================================= */
.site-footer{background:var(--brand-900);color:rgba(255,255,255,.6);padding:64px 0 28px;}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1.2fr;gap:40px;margin-bottom:48px;}
@media (max-width:820px){ .footer-grid{grid-template-columns:1fr 1fr;} }
.site-footer h5{color:#fff;font-family:var(--font-mono);font-size:13px;text-transform:uppercase;letter-spacing:.06em;margin-bottom:16px;}
.site-footer .brand{margin-bottom:14px;}
.site-footer p{font-size:14px;line-height:1.7;max-width:320px;}
.site-footer ul li{margin-bottom:10px;}
.site-footer a{font-size:14px;color:rgba(255,255,255,.6);transition:color .15s;}
.site-footer a:hover{color:var(--cyan-300);}
.footer-bottom{
  border-top:1px solid rgba(255,255,255,.08);padding-top:24px;
  display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:13px;
}

/* =========================================================
   REGISTER PAGE / FORM
   ========================================================= */
.page-banner{
  background:linear-gradient(135deg,var(--brand-900),var(--brand-700));
  color:#fff;padding:64px 0 60px;text-align:center;
}
.page-banner .eyebrow{background:rgba(255,255,255,.08);border-color:rgba(255,255,255,.18);color:var(--cyan-300);}
.page-banner h1{color:#fff;font-size:clamp(30px,4vw,42px);}
.page-banner p{color:rgba(255,255,255,.72);max-width:560px;margin:0 auto;}

.form-wrap{max-width:760px;margin:-40px auto 0;position:relative;}
.form-card{
  background:var(--surface);border-radius:var(--radius-lg);box-shadow:var(--shadow-lg);
  border:1px solid var(--line);padding:44px;
}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;}
@media (max-width:640px){ .form-grid{grid-template-columns:1fr;} }
.form-group{display:flex;flex-direction:column;gap:7px;margin-bottom:20px;}
.form-group.full{grid-column:1 / -1;}
.form-group label{font-size:13.5px;font-weight:600;color:var(--ink);}
.form-group label .req{color:var(--error);}
.form-group input,
.form-group select{
  border:1.5px solid var(--line);border-radius:9px;padding:12px 14px;
  font-family:var(--font-body);font-size:14.5px;color:var(--ink);
  background:var(--surface);transition:border-color .15s, box-shadow .15s;
}
.form-group input:focus,
.form-group select:focus{
  outline:none;border-color:var(--brand-500);box-shadow:0 0 0 3px rgba(79,70,229,.14);
}
.form-group .hint{font-size:12px;color:var(--error);min-height:14px;}
.form-note{font-size:12.5px;color:var(--ink-faint);margin-top:6px;}

.alert{border-radius:10px;padding:16px 18px;font-size:14.5px;margin-bottom:24px;display:flex;gap:10px;align-items:flex-start;}
.alert-success{background:rgba(31,163,123,.09);border:1px solid rgba(31,163,123,.35);color:#0E6B4F;}
.alert-error{background:rgba(225,75,75,.08);border:1px solid rgba(225,75,75,.3);color:#B8302F;}

/* =========================================================
   ABOUT PAGE
   ========================================================= */
.about-hero{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center;}
@media (max-width:900px){ .about-hero{grid-template-columns:1fr;} }
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:24px;}
@media (max-width:700px){ .stat-grid{grid-template-columns:repeat(2,1fr);} }
.stat-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md);padding:24px;text-align:center;box-shadow:var(--shadow-sm);}
.stat-card b{display:block;font-family:var(--font-display);font-size:30px;color:var(--brand-500);}
.stat-card span{font-size:13px;color:var(--ink-faint);}
.values-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;}
@media (max-width:820px){ .values-grid{grid-template-columns:1fr;} }
.value-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md);padding:26px;}
.value-card .num{font-family:var(--font-mono);color:var(--cyan-400);font-size:13px;margin-bottom:10px;display:block;}

.mock{width:100%;aspect-ratio:4/3;border-radius:var(--radius-lg);background:
  radial-gradient(400px 260px at 20% 10%, rgba(79,70,229,.35), transparent 60%),
  radial-gradient(300px 240px at 90% 90%, rgba(23,195,214,.35), transparent 60%),
  linear-gradient(160deg,var(--brand-900),var(--brand-700));
  position:relative;overflow:hidden;box-shadow:var(--shadow-lg);
}