/* ═══ TRAINING PAGES — LIGHT THEME ═══ */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
:root{
  --bg:#f5f5f0;--bg2:#ffffff;--bg3:#efefe8;--bg4:#e8e8e0;
  --text:#1a1a1a;--text2:#6b6b6b;--text3:#9a9a94;
  --accent:#2a6f6a;--accent2:#39837d;
  --green:#10b981;--green2:#34d399;--red:#ef4444;--blue:#60a5fa;
  --radius:12px;--radius-sm:8px;--radius-lg:20px;
  --sidebar-w:260px;
}
html{scroll-behavior:smooth}
body{font-family:'Inter',system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.7;overflow-x:hidden}
code,pre,.mono{font-family:'JetBrains Mono',monospace}
a{color:var(--accent);text-decoration:none;transition:color .2s}
a:hover{color:var(--accent2);text-decoration:underline}

/* ═══ TOP BAR ═══ */
.topbar{position:fixed;top:0;left:0;right:0;z-index:100;height:56px;background:var(--bg2);border-bottom:1px solid #e0e0d8;display:flex;align-items:center;justify-content:space-between;padding:0 1.5rem}
.topbar-left{display:flex;align-items:center;gap:1rem}
.topbar-back{display:inline-flex;align-items:center;gap:.4rem;color:var(--text3);font-size:.82rem;font-weight:500;padding:.35rem .8rem;border-radius:var(--radius-sm);transition:background .2s}
.topbar-back:hover{color:var(--text);background:var(--bg3)}
.topbar-title{font-weight:700;font-size:.92rem;color:var(--accent)}
.topbar-right{display:flex;align-items:center;gap:1rem}
.topbar-prog{font-size:.75rem;color:var(--text3);font-weight:600}
.topbar-prog-bar{width:120px;height:4px;background:var(--bg3);border-radius:2px;overflow:hidden}
.topbar-prog-fill{height:100%;border-radius:2px;background:var(--accent);transition:width .4s}

/* ═══ SIDEBAR ═══ */
.sidebar{position:fixed;top:56px;left:0;bottom:0;width:var(--sidebar-w);background:var(--bg2);border-right:1px solid #e0e0d8;overflow-y:auto;padding:1.5rem 0;z-index:50}
.sidebar::-webkit-scrollbar{width:4px}
.sidebar::-webkit-scrollbar-thumb{background:var(--bg4);border-radius:2px}
.sidebar-section{padding:0 1rem;margin-bottom:1.2rem}
.sidebar-section-title{font-size:.65rem;font-weight:700;color:var(--text3);text-transform:uppercase;letter-spacing:.15em;margin-bottom:.5rem;padding-left:.5rem}
.sidebar-link{display:flex;align-items:center;gap:.6rem;padding:.45rem .7rem;border-radius:var(--radius-sm);font-size:.8rem;font-weight:500;color:var(--text2);transition:background .2s;cursor:pointer;margin-bottom:.15rem}
.sidebar-link:hover{background:var(--bg3);color:var(--text)}
.sidebar-link.active{background:rgba(42,111,106,.1);color:var(--accent);font-weight:600}
.sidebar-link.completed{color:var(--green)}
.sidebar-link .step-num{width:22px;height:22px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:.65rem;font-weight:700;background:var(--bg3);color:var(--text3);flex-shrink:0;transition:background .2s}
.sidebar-link.active .step-num{background:var(--accent);color:#fff}
.sidebar-link.completed .step-num{background:var(--green);color:#fff}
.sidebar-progress{margin:0 1rem 1rem;padding:.8rem;background:var(--bg3);border-radius:var(--radius-sm);text-align:center}
.sidebar-progress .pct{font-size:1.5rem;font-weight:900;color:var(--accent)}
.sidebar-progress .pct-label{font-size:.65rem;color:var(--text3);text-transform:uppercase;letter-spacing:.1em}

/* ═══ MAIN CONTENT ═══ */
.main{margin-left:var(--sidebar-w);margin-top:56px;padding:3rem 3rem 4rem;max-width:860px}
.main h1{font-size:2rem;font-weight:800;margin-bottom:.5rem;line-height:1.2;color:var(--text)}
.main .subtitle{font-size:.9rem;color:var(--text2);margin-bottom:2rem}

/* Objectives box */
.objectives{background:rgba(42,111,106,.06);border:1px solid rgba(42,111,106,.18);border-radius:var(--radius);padding:1.2rem 1.5rem;margin-bottom:2.5rem}
.objectives h3{font-size:.75rem;font-weight:700;color:var(--accent);text-transform:uppercase;letter-spacing:.1em;margin-bottom:.7rem}
.objectives li{font-size:.88rem;color:var(--text2);padding:.2rem 0;padding-left:1.8rem;position:relative}
.objectives li::before{content:'🎯';position:absolute;left:0;font-size:.85rem;top:.25rem}

/* Section headers */
.main h2{font-size:1.35rem;font-weight:700;margin:2.5rem 0 .8rem;padding-bottom:.5rem;border-bottom:1px solid #e0e0d8;color:var(--text)}
.main h3{font-size:1.05rem;font-weight:600;margin:1.5rem 0 .5rem;color:var(--text)}
.main p{font-size:.92rem;color:var(--text2);margin-bottom:1rem;line-height:1.75}
.main ul,.main ol{margin:0 0 1rem 1.5rem;font-size:.9rem;color:var(--text2)}
.main li{padding:.15rem 0}

/* ═══ CODE BLOCKS ═══ */
.code-block{background:var(--bg2);border:1px solid #e0e0d8;border-radius:var(--radius);margin:1rem 0 1.5rem;overflow:hidden}
.code-block-header{display:flex;justify-content:space-between;align-items:center;padding:.6rem 1rem;background:var(--bg3);border-bottom:1px solid #e0e0d8;font-size:.72rem;font-weight:600;color:var(--text3);text-transform:uppercase;letter-spacing:.06em}
.code-block-header .lang{color:var(--accent)}
.copy-btn{background:none;border:1px solid #e0e0d8;border-radius:4px;padding:.2rem .6rem;color:var(--text3);font-size:.7rem;cursor:pointer;font-family:inherit;transition:all .2s}
.copy-btn:hover{color:var(--text);border-color:var(--accent)}
.copy-btn.copied{color:var(--green2);border-color:var(--green)}
.code-block pre{padding:1rem 1.2rem;overflow-x:auto;font-size:.82rem;line-height:1.7;color:var(--text2);background:#fafaf5}
.code-block pre::-webkit-scrollbar{height:4px}
.code-block pre::-webkit-scrollbar-thumb{background:var(--bg4);border-radius:2px}

/* Inline code */
.main p code,.main li code{background:var(--bg3);padding:.1rem .4rem;border-radius:4px;font-size:.8rem;color:var(--accent)}

/* Syntax highlighting — light theme */
.kw{color:#8250df}.fn{color:#0550ae}.str{color:#0a3069}.num{color:#953800}.cm{color:#6e7781;font-style:italic}
.op{color:#0550ae}.var{color:#1a1a1a}.cls{color:#953800}.dec{color:#8250df}.type{color:#953800}
.err{color:#cf222e}.punct{color:#57606a}

/* ═══ CALLOUT BOXES ═══ */
.callout{border-radius:var(--radius-sm);padding:1rem 1.2rem;margin:1.2rem 0;display:flex;gap:.75rem;align-items:flex-start}
.callout-icon{font-size:1.1rem;flex-shrink:0;margin-top:1px}
.callout-body{flex:1}
.callout-body h4{font-size:.82rem;font-weight:700;margin-bottom:.3rem}
.callout-body p,.callout-body li{font-size:.85rem;color:var(--text2);line-height:1.65}
.callout-body ul{margin:.3rem 0 0 1rem}

.callout-tip{background:rgba(16,185,129,.06);border:1px solid rgba(16,185,129,.18);border-left:3px solid var(--green)}
.callout-tip h4{color:var(--green)}

.callout-warning{background:rgba(239,68,68,.06);border:1px solid rgba(239,68,68,.18);border-left:3px solid var(--red)}
.callout-warning h4{color:var(--red)}

.callout-info{background:rgba(96,165,250,.06);border:1px solid rgba(96,165,250,.18);border-left:3px solid var(--blue)}
.callout-info h4{color:var(--blue)}

.callout-exercise{background:rgba(42,111,106,.06);border:1px solid rgba(42,111,106,.18);border-left:3px solid var(--accent)}
.callout-exercise h4{color:var(--accent)}

/* ═══ STEP INDICATORS ═══ */
.step-row{display:flex;gap:1rem;margin:2rem 0 1rem;align-items:flex-start}
.step-num-big{width:40px;height:40px;border-radius:50%;background:var(--accent);display:flex;align-items:center;justify-content:center;font-weight:800;font-size:.9rem;color:#fff;flex-shrink:0}
.step-content{flex:1}
.step-content h3{margin:0 0 .5rem;font-size:1.05rem;font-weight:700;color:var(--text)}

/* ═══ NAVIGATION ═══ */
.nav-footer{display:flex;justify-content:space-between;align-items:center;margin-top:4rem;padding-top:2rem;border-top:1px solid #e0e0d8}
.nav-btn{display:inline-flex;align-items:center;gap:.5rem;padding:.7rem 1.5rem;border-radius:var(--radius-sm);font-weight:600;font-size:.88rem;border:none;cursor:pointer;transition:all .2s;font-family:inherit}
.nav-btn-prev{background:var(--bg3);color:var(--text2);border:1px solid #e0e0d8}
.nav-btn-prev:hover{background:var(--bg4);color:var(--text)}
.nav-btn-next{background:var(--accent);color:#fff}
.nav-btn-next:hover{background:var(--accent2)}
.nav-btn.disabled{opacity:.3;cursor:not-allowed}
.nav-btn-mark{background:var(--bg3);color:var(--green);border:1px solid rgba(16,185,129,.3)}
.nav-btn-mark:hover{background:rgba(16,185,129,.08)}
.nav-btn-mark.completed{background:var(--green);color:#fff;border-color:var(--green)}
.nav-btn-group{display:flex;gap:.75rem;align-items:center}

/* ═══ COMPLETION CHECK ═══ */
.completion-box{background:var(--bg2);border:1px solid #e0e0d8;border-radius:var(--radius);padding:1.5rem;margin-top:2rem}
.completion-box h3{font-size:.95rem;font-weight:700;margin-bottom:.8rem}
.completion-check{display:flex;align-items:center;gap:.75rem;padding:.5rem 0;cursor:pointer;font-size:.88rem;color:var(--text2);transition:color .2s}
.completion-check:hover{color:var(--text)}
.completion-check input{width:18px;height:18px;accent-color:var(--accent);cursor:pointer}
.completion-check.checked{color:var(--green)}

/* ═══ RESPONSIVE ═══ */
@media(max-width:900px){
  .sidebar{transform:translateX(-100%)}
  .sidebar.open{transform:translateX(0)}
  .main{margin-left:0;padding:2rem 1.5rem 3rem}
  .menu-toggle{display:flex!important}
}
@media(max-width:600px){
  .main{padding:1.5rem 1rem 3rem}
  .main h1{font-size:1.5rem}
  .objectives{padding:1rem}
  .objectives li{padding-left:1.6rem}
  .step-row{flex-direction:column;gap:.5rem}
  .step-num-big{width:32px;height:32px;font-size:.8rem}
  .callout{flex-direction:column;gap:.5rem}
  .callout-icon{font-size:1rem}
  .nav-footer{flex-direction:column;gap:1rem}
  .nav-btn-group{flex-direction:column;width:100%}
  .nav-btn{width:100%;justify-content:center}
}
.menu-toggle{display:none;align-items:center;justify-content:center;width:36px;height:36px;border-radius:var(--radius-sm);background:var(--bg3);border:none;color:var(--text2);cursor:pointer;font-size:1.2rem}