/* ═══ AI Engineer Roadmap — Shared Styles ═══ */
:root{
  --bg:#f5f5f0;
  --bg2:#ffffff;
  --bg3:#efefe8;
  --bg4:#e8e8e0;
  --surface:rgba(0,0,0,.015);
  --border:#e0e0d8;
  --text:#1a1a1a;
  --text2:#6b6b6b;
  --text3:#9a9a94;
  --accent:#2a6f6a;
  --accent2:#39837d;
  --green:#2a8a5a;
  --green2:#3a9a6a;
  --red:#c75a4a;
  --orange:#c48a3a;
  --blue:#3a6a8a;
  --radius:8px;
  --radius-sm:6px;
}
html{scroll-behavior:smooth}
body{font-family:'Inter',system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;-webkit-font-smoothing:antialiased}
code,.mono{font-family:'JetBrains Mono',monospace}
a{color:var(--accent);text-decoration:none}
a:hover{color:var(--accent2);text-decoration:underline}

/* ═══ NAV ═══ */
nav{position:fixed;top:0;left:0;right:0;z-index:100;background:var(--bg2);border-bottom:1px solid var(--border);padding:0 1.5rem;height:52px;display:flex;align-items:center;justify-content:space-between}
.nav-logo{font-weight:800;font-size:.95rem;color:var(--text);white-space:nowrap}
.nav-links{display:flex;gap:.25rem;align-items:center}
.nav-links a{color:var(--text2);font-size:.78rem;font-weight:500;padding:.35rem .6rem;border-radius:var(--radius-sm);transition:background .2s}
.nav-links a:hover,.nav-links a.active{color:var(--text);background:var(--bg3);text-decoration:none}
.nav-quiz{background:var(--accent);color:#fff!important;font-weight:600!important;border-radius:var(--radius-sm)!important}
.nav-quiz:hover{background:var(--accent2)!important;text-decoration:none!important}
.nav-achievements{font-size:1.1rem;padding:.35rem .5rem!important}
.nav-hamburger{display:none;background:none;border:none;color:var(--text);font-size:1.3rem;cursor:pointer;padding:.3rem;z-index:101}
.nav-overlay{display:none;position:fixed;top:0;left:0;right:0;bottom:0;background:rgba(0,0,0,.3);z-index:98;opacity:0;transition:opacity .3s;pointer-events:none}
.nav-overlay.open{display:block;opacity:1;pointer-events:auto}
@media(max-width:900px){
  .nav-hamburger{display:block}
  .nav-links{position:fixed;top:52px;left:0;right:0;background:var(--bg2);flex-direction:column;padding:.75rem;gap:.15rem;transform:translateY(-120%);transition:transform .3s;z-index:99;border-bottom:1px solid var(--border)}
  .nav-links.open{transform:translateY(0)}
  .nav-links a{padding:.5rem .75rem;width:100%;text-align:left;border-radius:var(--radius-sm)}
  .nav-links .nav-quiz{margin-top:.15rem;width:100%;text-align:center}
}

/* ═══ HERO ═══ */
.hero{min-height:70vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:6rem 1.5rem 3rem}
.hero-content{max-width:680px}
.hero-badge{display:inline-flex;align-items:center;gap:.4rem;border:1px solid var(--border);border-radius:50px;padding:.3rem .85rem;font-size:.7rem;font-weight:600;color:var(--text2);margin-bottom:1.5rem}
.hero-badge .dot{width:6px;height:6px;border-radius:50%;display:inline-block;background:var(--green)}
.hero h1{font-size:clamp(2rem,5vw,3.5rem);font-weight:900;line-height:1.1;margin-bottom:.75rem;color:var(--text)}
.hero p{font-size:1rem;color:var(--text2);max-width:540px;margin:0 auto 1.75rem;line-height:1.7}
.hero-buttons{display:flex;gap:.75rem;justify-content:center;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:.4rem;padding:.65rem 1.4rem;border-radius:var(--radius-sm);font-weight:600;font-size:.85rem;border:1px solid var(--border);cursor:pointer;transition:background .2s;font-family:inherit;background:var(--bg2);color:var(--text)}
.btn:hover{background:var(--bg3);text-decoration:none}
.btn-primary{background:var(--accent);color:#fff;border-color:var(--accent)}
.btn-primary:hover{background:var(--accent2);border-color:var(--accent2)}
.btn-secondary{background:var(--bg2);color:var(--text);border:1px solid var(--border)}
.btn-secondary:hover{background:var(--bg3)}
.btn-sm{padding:.35rem .9rem;font-size:.78rem}
.btn-green{background:var(--green);color:#fff;border-color:var(--green)}
.btn-green:hover{background:var(--green2);border-color:var(--green2)}

/* ═══ SECTIONS ═══ */
.section{padding:4rem 1.5rem;max-width:960px;margin:0 auto}
.section-header{text-align:center;margin-bottom:2.5rem}
.section-header h2{font-size:1.6rem;font-weight:800;margin-bottom:.4rem;color:var(--text)}
.section-header p{color:var(--text2);font-size:.9rem}

/* ═══ TIMELINE ═══ */
.timeline{display:flex;flex-direction:column;gap:0;position:relative;padding-left:2rem}
.timeline::before{content:'';position:absolute;left:9px;top:0;bottom:0;width:2px;background:var(--border);border-radius:1px}
.timeline-item{position:relative;padding:1rem 0 1.5rem}
.timeline-dot{position:absolute;left:-2rem;top:1.4rem;width:22px;height:22px;border-radius:50%;background:var(--bg2);border:2px solid var(--border);display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.6rem;color:var(--text2);z-index:1}
.month-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.25rem}
.month-card:hover{border-color:var(--accent)}
.month-num{font-size:.65rem;font-weight:700;color:var(--accent);text-transform:uppercase;letter-spacing:.12em;margin-bottom:.35rem}
.month-card h3{font-size:1.1rem;font-weight:700;margin-bottom:.25rem;color:var(--text)}
.month-card>p{color:var(--text2);font-size:.85rem;margin-bottom:.75rem}
.skill-tags{display:flex;flex-wrap:wrap;gap:.35rem;margin-bottom:.75rem}
.tag{display:inline-block;padding:.2rem .55rem;border-radius:50px;font-size:.68rem;font-weight:500;border:1px solid var(--border);color:var(--text2)}
.tag:hover{border-color:var(--accent);color:var(--accent)}
.month-card .btn{margin-top:.35rem}

/* ═══ COMPARE ═══ */
.compare-grid{display:grid;grid-template-columns:1fr 1fr;gap:1.25rem;margin-top:1.25rem}
.compare-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.25rem}
.compare-card h3{font-size:1.1rem;font-weight:700;margin-bottom:.75rem;color:var(--text)}
.compare-row{display:flex;justify-content:space-between;padding:.45rem 0;border-bottom:1px solid var(--border);font-size:.82rem}
.compare-row:last-child{border:none}
.compare-label{color:var(--text3);font-weight:500}
.compare-val{color:var(--text);font-weight:500;text-align:right;max-width:60%}

/* ═══ SALARY TABLE ═══ */
.salary-table{width:100%;border-collapse:collapse;margin-top:1.25rem;font-size:.85rem}
.salary-table th,.salary-table td{padding:.7rem;text-align:left;border-bottom:1px solid var(--border)}
.salary-table th{color:var(--text3);font-weight:600;text-transform:uppercase;font-size:.68rem;letter-spacing:.06em}
.salary-table td{color:var(--text2)}
.salary-table tr:hover td{background:var(--bg3)}
.salary-range{font-family:'JetBrains Mono',monospace;color:var(--accent);font-weight:600;font-size:.85rem}

/* ═══ QUICK START ═══ */
.qs-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:.85rem;margin-top:1.25rem}
.qs-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.15rem}
.qs-card:hover{border-color:var(--accent)}
.qs-day{font-size:.65rem;font-weight:700;color:var(--accent);text-transform:uppercase;letter-spacing:.06em;margin-bottom:.25rem}
.qs-card h4{font-size:.9rem;font-weight:600;margin-bottom:.25rem;color:var(--text)}
.qs-card p{font-size:.82rem;color:var(--text2)}

/* ═══ QUIZ ═══ */
.quiz-area{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.75rem;min-height:320px}
.quiz-topics{display:grid;grid-template-columns:repeat(auto-fill,minmax(155px,1fr));gap:.7rem;margin-bottom:1.25rem}
.topic-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1rem;cursor:pointer;transition:border-color .2s;text-align:center;user-select:none;-webkit-user-select:none;-webkit-tap-highlight-color:transparent;touch-action:manipulation;pointer-events:auto}
.topic-card:hover,.topic-card.active{border-color:var(--accent)}
.topic-icon{font-size:1.8rem;margin-bottom:.35rem}
.topic-card h4{font-size:.78rem;font-weight:600;color:var(--text)}
.topic-card .q-count{font-size:.65rem;color:var(--text3);margin-top:.15rem}
.topic-progress{margin-top:.35rem;height:3px;background:var(--bg4);border-radius:2px;overflow:hidden}
.topic-progress-fill{height:100%;border-radius:2px;background:var(--accent);transition:width .4s}
.topic-score{font-size:.7rem;font-weight:700;margin-top:.2rem}

.quiz-progress{display:flex;align-items:center;gap:.75rem;margin-bottom:1.25rem}
.quiz-progress .progress-bar{flex:1;height:4px;background:var(--bg4);border-radius:2px;overflow:hidden}
.quiz-progress .progress-fill{height:100%;border-radius:2px;background:var(--accent);transition:width .4s}
.quiz-progress .progress-text{font-size:.75rem;color:var(--text3);font-weight:600;white-space:nowrap}

.quiz-question-num{font-size:.7rem;font-weight:700;color:var(--accent);text-transform:uppercase;letter-spacing:.06em;margin-bottom:.35rem}
.quiz-question{font-size:1rem;font-weight:600;line-height:1.5;margin-bottom:1.1rem;color:var(--text)}
.quiz-options{display:flex;flex-direction:column;gap:.55rem;margin-bottom:1.25rem}
.quiz-option{padding:.8rem 1rem;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--surface);cursor:pointer;transition:background .15s;font-size:.85rem;display:flex;align-items:flex-start;gap:.6rem}
.quiz-option:hover:not(.disabled){border-color:var(--accent);background:var(--bg3)}
.quiz-option .opt-letter{display:inline-flex;align-items:center;justify-content:center;width:24px;height:24px;border-radius:4px;background:var(--bg3);font-size:.7rem;font-weight:700;color:var(--text3);flex-shrink:0;margin-top:1px}
.quiz-option.selected .opt-letter{background:var(--accent);color:#fff}
.quiz-option.correct{border-color:var(--green);background:rgba(42,138,90,.05)}
.quiz-option.correct .opt-letter{background:var(--green);color:#fff}
.quiz-option.incorrect{border-color:var(--red);background:rgba(199,90,74,.05)}
.quiz-option.incorrect .opt-letter{background:var(--red);color:#fff}
.quiz-option.disabled{cursor:default;opacity:.6}
.quiz-feedback{padding:.75rem 1rem;border-radius:var(--radius-sm);margin-bottom:1.1rem;font-size:.82rem;display:none}
.quiz-feedback.show{display:flex;align-items:flex-start;gap:.6rem}
.quiz-feedback.correct-fb{background:rgba(42,138,90,.06);border:1px solid rgba(42,138,90,.15);color:var(--green)}
.quiz-feedback.incorrect-fb{background:rgba(199,90,74,.06);border:1px solid rgba(199,90,74,.15);color:var(--red)}
.quiz-nav{display:flex;justify-content:space-between;align-items:center}
.quiz-nav .btn:disabled{opacity:.4;cursor:not-allowed}

.round-selector{display:flex;gap:.35rem;flex-wrap:wrap;margin-bottom:1.1rem}
.round-btn{padding:.3rem .75rem;border-radius:50px;font-size:.68rem;font-weight:600;border:1px solid var(--border);background:var(--bg2);color:var(--text2);cursor:pointer;transition:background .15s}
.round-btn:hover{border-color:var(--accent);color:var(--accent)}
.round-btn.active{background:var(--accent);color:#fff;border-color:var(--accent)}
.round-btn.completed{border-color:var(--green);color:var(--green)}
.round-btn.locked{opacity:.35;cursor:not-allowed}

.eval-header{text-align:center;margin-bottom:1.25rem}
.eval-header h3{font-size:1.2rem;font-weight:800;margin-bottom:.15rem;color:var(--text)}
.eval-header p{color:var(--text2);font-size:.85rem}
.eval-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:.85rem;margin-bottom:1.25rem}
.eval-stat{text-align:center;padding:1.1rem;background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius)}
.eval-stat .stat-num{font-size:1.6rem;font-weight:900;line-height:1;color:var(--text)}
.eval-stat .stat-label{font-size:.65rem;color:var(--text3);text-transform:uppercase;letter-spacing:.06em;margin-top:.2rem;font-weight:600}
.eval-breakdown{margin-bottom:1.25rem}
.eval-breakdown h4{font-size:.75rem;color:var(--text3);text-transform:uppercase;letter-spacing:.06em;margin-bottom:.65rem;font-weight:600}
.eval-bar{display:flex;align-items:center;gap:.6rem;margin-bottom:.35rem}
.eval-bar-label{font-size:.78rem;color:var(--text2);width:125px;flex-shrink:0}
.eval-bar-track{flex:1;height:6px;background:var(--bg4);border-radius:3px;overflow:hidden}
.eval-bar-fill{height:100%;border-radius:3px;transition:width .6s}
.eval-bar-pct{font-size:.7rem;font-weight:700;width:35px;text-align:right;flex-shrink:0}
.eval-advice{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.1rem;margin-bottom:1.25rem}
.eval-advice h4{font-size:.85rem;font-weight:700;margin-bottom:.3rem;color:var(--text)}
.eval-advice p{font-size:.82rem;color:var(--text2)}
.eval-actions{display:flex;gap:.7rem;justify-content:center;flex-wrap:wrap}

.quiz-start{text-align:center;padding:2rem 1.5rem}
.quiz-start-icon{font-size:3rem;margin-bottom:.85rem}
.quiz-start h3{font-size:1.2rem;font-weight:700;margin-bottom:.3rem;color:var(--text)}
.quiz-start p{color:var(--text2);font-size:.85rem;margin-bottom:1.25rem;max-width:420px;margin-left:auto;margin-right:auto}

/* ═══ ACHIEVEMENTS ═══ */
.achievement-header{text-align:center;margin-bottom:2.5rem}
.achievement-ring{width:110px;height:110px;margin:0 auto 1rem;position:relative}
.achievement-ring svg{transform:rotate(-90deg);width:110px;height:110px}
.achievement-ring-bg{fill:none;stroke:var(--bg4);stroke-width:7}
.achievement-ring-fill{fill:none;stroke:var(--accent);stroke-width:7;stroke-linecap:round;stroke-dasharray:345;stroke-dashoffset:345;transition:stroke-dashoffset 1s}
.achievement-percent{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);text-align:center}
.achievement-percent .pct{font-size:1.6rem;font-weight:900;color:var(--accent)}
.achievement-percent .label{font-size:.65rem;color:var(--text3);text-transform:uppercase;letter-spacing:.06em}
.achievement-stats{display:flex;justify-content:center;gap:1.5rem;margin-top:.65rem}
.achievement-stat{text-align:center}
.achievement-stat .num{font-size:1.2rem;font-weight:700;color:var(--green)}
.achievement-stat .lbl{font-size:.65rem;color:var(--text3);text-transform:uppercase}
.achievement-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:.85rem}
.achievement-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:1.15rem}
.achievement-card.unlocked{border-color:var(--green)}
.achievement-card.locked{opacity:.45}
.achievement-card.locked .achievement-icon{filter:grayscale(1)}
.achievement-icon{width:40px;height:40px;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center;font-size:1.3rem;margin-bottom:.65rem;background:var(--bg3);border:1px solid var(--border)}
.achievement-name{font-size:.85rem;font-weight:700;margin-bottom:.2rem;color:var(--text)}
.achievement-desc{font-size:.72rem;color:var(--text2);margin-bottom:.5rem;line-height:1.4}
.achievement-progress{height:4px;background:var(--bg4);border-radius:2px;overflow:hidden;margin-bottom:.2rem}
.achievement-progress-fill{height:100%;border-radius:2px;background:var(--accent);transition:width .5s}
.achievement-progress-text{font-size:.65rem;color:var(--text3);display:flex;justify-content:space-between}
.achievement-badge{position:absolute;top:8px;right:8px;font-size:.8rem}

/* ═══ FOOTER ═══ */
footer{border-top:1px solid var(--border);padding:2rem 1.5rem;text-align:center;color:var(--text3);font-size:.78rem}
footer a{color:var(--accent)}

/* ═══ SCROLL ═══ */
.scroll-top{position:fixed;bottom:1.5rem;right:1.5rem;width:36px;height:36px;border-radius:50%;background:var(--accent);color:#fff;border:none;cursor:pointer;font-size:1rem;display:flex;align-items:center;justify-content:center;z-index:150;opacity:0;transition:opacity .2s;transform:translateY(10px)}
.scroll-top.show{opacity:1;transform:translateY(0)}
.scroll-top:hover{background:var(--accent2)}

/* ═══ DIVIDER ═══ */
.section-divider{height:1px;background:var(--border);margin:0 auto;max-width:400px}

/* ═══ RESPONSIVE ═══ */
@media(max-width:768px){
  .section{padding:2.5rem 1rem}
  .section-header h2{font-size:1.3rem}
  .hero h1{font-size:clamp(1.6rem,7vw,2.2rem)}
  .hero p{font-size:.9rem}
  .hero{min-height:auto;padding:4.5rem 1rem 2.5rem}
  .compare-grid{grid-template-columns:1fr}
  .qs-grid{grid-template-columns:1fr}
  .quiz-topics{grid-template-columns:repeat(2,1fr)}
  .timeline{padding-left:1.5rem}
  .timeline-dot{left:-1.5rem;width:20px;height:20px;font-size:.55rem}
  .eval-stats{grid-template-columns:1fr}
  .month-card{padding:1rem}
  .achievement-grid{grid-template-columns:1fr 1fr}
  .quiz-area{padding:1.1rem}
}
@media(max-width:480px){
  .hero{padding:3.5rem .75rem 2rem}
  .hero h1{font-size:1.4rem}
  .hero p{font-size:.85rem}
  .section{padding:2rem .75rem}
  .section-header h2{font-size:1.15rem}
  .timeline{padding-left:1.25rem}
  .timeline-dot{left:-1.25rem;width:18px;height:18px;font-size:.5rem}
  .month-card{padding:.85rem}
  .quiz-topics{grid-template-columns:1fr}
  .quiz-question{font-size:.9rem}
  .quiz-option{padding:.65rem .8rem;font-size:.8rem}
  .quiz-area{padding:.85rem}
  .achievement-grid{grid-template-columns:1fr}
}
</style>