/* ── RESET + VARIABLES ────────────────────────────────────────── */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --bg:     #1A1C20;
  --bg2:    #212328;
  --bg3:    #292B31;
  --bg4:    #313439;
  --border: rgba(255,255,255,0.07);
  --border2:rgba(255,255,255,0.13);
  --text:   #E5E5E5;
  --muted:  #6A6A75;
  --muted2: #9A9AA8;
  --green:  #2EC866;
  --gdim:   rgba(46,200,102,0.12);
  --gborder:rgba(46,200,102,0.28);
  --yellow: #F5A623;
  --red:    #EF5656;
  --blue:   #4A9EFF;
  --sans:   'Hanken Grotesk','Helvetica Neue',Helvetica,sans-serif;
  --mono:   'JetBrains Mono',monospace;
}
html{scroll-behavior:smooth}
body{background:var(--bg);color:var(--text);font-family:var(--sans);font-size:15px;line-height:1.6;font-weight:400;overflow-x:hidden}
a{color:inherit;text-decoration:none}
code{font-family:var(--mono);font-size:.85em;background:var(--bg3);border:1px solid var(--border2);padding:1px 5px;border-radius:3px;color:var(--green)}

/* ── AUTH GUARD ──────────────────────────────────────────────── */
body.auth-pending main,
body.auth-pending .main,
body.auth-pending .page-content{visibility:hidden}

/* ── NAV ─────────────────────────────────────────────────────── */
nav{position:sticky;top:0;z-index:100;height:58px;display:flex;align-items:center;justify-content:space-between;padding:0 2rem;background:var(--bg2);border-bottom:1px solid var(--border)}
.nav-left{display:flex;align-items:center;gap:2rem}
.logo{display:flex;align-items:center;gap:10px;text-decoration:none}
.logo-mark{width:28px;height:28px;background:var(--green);border-radius:6px;display:flex;align-items:center;justify-content:center;font-family:var(--mono);font-size:13px;font-weight:500;color:#0D1A12;flex-shrink:0}
.logo-text{font-family:var(--mono);font-size:14px;font-weight:500;color:var(--text);letter-spacing:.02em}
.nav-tabs{display:flex;gap:0;list-style:none}
.nav-tabs a{padding:8px 16px;font-size:13px;font-weight:400;color:var(--muted2);text-decoration:none;border-bottom:2px solid transparent;transition:all .2s;display:flex;align-items:center;gap:6px;height:58px;margin-top:-1px}
.nav-tabs a.active{color:var(--green);border-bottom-color:var(--green)}
.nav-tabs a:hover:not(.active):not(.locked){color:var(--text)}
.nav-tabs .locked{opacity:.35;cursor:default;pointer-events:none}
.lock{font-size:10px}
.nav-right{display:flex;align-items:center;gap:10px;font-family:var(--mono);font-size:12px;color:var(--muted2)}
.pts-val{color:var(--green);font-weight:500}
.btn-nav{padding:8px 18px;background:var(--green);color:#0D1A12;border:none;border-radius:4px;font-size:13px;font-weight:600;font-family:var(--sans);cursor:pointer;text-decoration:none;transition:background .2s}
.btn-nav:hover{background:#3dd974}
.nav-avatar{display:none;align-items:center;gap:8px;padding:4px 10px;background:var(--bg3);border:1px solid var(--border2);border-radius:6px}
.nav-avatar img{width:22px;height:22px;border-radius:50%;object-fit:cover}
.av-name{font-size:12px;color:var(--muted2)}
.nav-sign-in{padding:7px 16px;background:var(--green);color:#0D1A12;border:none;border-radius:4px;font-size:12px;font-weight:600;font-family:var(--sans);cursor:pointer;transition:background .2s}
.nav-sign-in:hover{background:#3dd974}
.nav-sign-out{display:none;padding:7px 14px;background:transparent;color:var(--muted2);border:1px solid var(--border2);border-radius:4px;font-size:12px;font-family:var(--sans);cursor:pointer;transition:all .2s}
.nav-sign-out:hover{color:var(--text)}
.nav-pts{font-family:var(--mono);font-size:12px;color:var(--muted2)}

/* ── SHARED LAYOUT ───────────────────────────────────────────── */
.container{max-width:1100px;margin:0 auto;padding:0 2rem}
.section{padding:5rem 0}
.section-tag{display:inline-flex;align-items:center;gap:8px;font-family:var(--mono);font-size:11px;font-weight:500;color:var(--green);letter-spacing:.1em;text-transform:uppercase;margin-bottom:1.25rem;padding:4px 10px;background:var(--gdim);border:1px solid var(--gborder);border-radius:4px}
h2{font-size:clamp(1.75rem,3.5vw,2.5rem);font-weight:600;line-height:1.2;margin-bottom:.75rem}
.sub{font-size:.95rem;color:var(--muted2);max-width:520px;line-height:1.7;margin-bottom:2.5rem}
.divider{border:none;border-top:1px solid var(--border);margin:0}

/* ── BUTTONS ─────────────────────────────────────────────────── */
.btn-primary{padding:11px 24px;background:var(--green);color:#0D1A12;border:none;border-radius:4px;font-size:14px;font-weight:600;font-family:var(--sans);cursor:pointer;text-decoration:none;transition:all .2s;display:inline-block}
.btn-primary:hover{background:#3dd974;transform:translateY(-1px)}
.btn-ghost{padding:10px 24px;background:transparent;color:var(--text);border:1px solid var(--border2);border-radius:4px;font-size:14px;font-weight:500;font-family:var(--sans);cursor:pointer;text-decoration:none;transition:all .2s;display:inline-block}
.btn-ghost:hover{border-color:var(--muted2);background:var(--bg3)}
.btn-danger{padding:7px 16px;background:transparent;color:var(--red);border:1px solid rgba(239,86,86,.3);border-radius:4px;font-size:12px;font-family:var(--sans);cursor:pointer;transition:all .2s}
.btn-danger:hover{background:rgba(239,86,86,.08)}

/* ── BADGES ──────────────────────────────────────────────────── */
.badge{font-family:var(--mono);font-size:10px;font-weight:500;letter-spacing:.08em;text-transform:uppercase;padding:3px 9px;border-radius:3px;display:inline-block}
.badge-num{background:var(--gdim);color:var(--green);border:1px solid var(--gborder)}
.badge-pts{background:var(--bg4);color:var(--muted2);border:1px solid var(--border2)}
.diff-badge{display:inline-block;font-family:var(--mono);font-size:10px;font-weight:500;padding:3px 9px;border-radius:3px;letter-spacing:.05em}
.diff-easy,.diff-beginner{background:rgba(46,200,102,.12);color:var(--green);border:1px solid rgba(46,200,102,.25)}
.diff-medium,.diff-intermediate{background:rgba(245,166,35,.12);color:var(--yellow);border:1px solid rgba(245,166,35,.25)}
.diff-hard,.diff-advanced{background:rgba(239,86,86,.12);color:var(--red);border:1px solid rgba(239,86,86,.25)}
.diff-expert{background:rgba(74,158,255,.12);color:var(--blue);border:1px solid rgba(74,158,255,.25)}

/* ── CHALLENGE BOARD ─────────────────────────────────────────── */
.ch-board{background:var(--bg2);border:1px solid var(--border);border-radius:8px;overflow:hidden}
.ch-board-hdr,.ch-board-header{display:grid;grid-template-columns:44px 1fr 110px 80px 90px;gap:0;padding:.65rem 1.5rem;border-bottom:1px solid var(--border);background:var(--bg3)}
.ch-col,.ch-col-label{font-family:var(--mono);font-size:10px;font-weight:500;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.ch-row{display:grid;grid-template-columns:44px 1fr 110px 80px 90px;gap:0;padding:1.1rem 1.5rem;border-bottom:1px solid var(--border);align-items:center;transition:background .15s;cursor:pointer}
.ch-row:last-child{border-bottom:none}
.ch-row.unlocked:hover{background:var(--bg3)}
.ch-row.locked-row{opacity:.5;cursor:default}
.ch-num{font-family:var(--mono);font-size:11px;color:var(--muted)}
.ch-info .ch-title{font-size:.95rem;font-weight:500;margin-bottom:.2rem}
.ch-info .ch-desc{font-size:.78rem;color:var(--muted)}
.ch-row.done-row .ch-title{color:var(--green)}
.ch-pts{font-family:var(--mono);font-size:12px;color:var(--muted2)}
.ch-action .action-btn,.ch-action .start-btn{padding:6px 14px;background:var(--green);color:#0D1A12;border:none;border-radius:3px;font-size:12px;font-weight:600;font-family:var(--sans);cursor:pointer;text-decoration:none;transition:background .2s;display:inline-block}
.ch-action .action-btn:hover,.ch-action .start-btn:hover{background:#3dd974}
.ch-action .action-done{padding:6px 14px;background:var(--gdim);color:var(--green);border:1px solid var(--gborder);border-radius:3px;font-size:12px;font-family:var(--mono);display:inline-block}
.ch-action .action-locked,.ch-action .locked-btn{padding:6px 14px;background:transparent;color:var(--muted);border:1px solid var(--border2);border-radius:3px;font-size:12px;font-family:var(--mono);display:inline-flex;align-items:center;gap:5px;cursor:not-allowed}

/* ── CARDS ────────────────────────────────────────────────────── */
.card{background:var(--bg2);border:1px solid var(--border);border-radius:8px;padding:1.5rem;transition:border-color .2s}
.card:hover{border-color:var(--border2)}
.card h3{font-size:1.05rem;font-weight:600;margin-bottom:.5rem}
.card p{font-size:.88rem;color:var(--muted2);line-height:1.7}

/* ── PAGE HEADER ─────────────────────────────────────────────── */
.page-header{padding:3rem 0 2rem;border-bottom:1px solid var(--border)}
.page-header-inner{display:flex;align-items:flex-start;justify-content:space-between;gap:2rem;flex-wrap:wrap}
.page-tag{display:inline-flex;align-items:center;gap:8px;font-family:var(--mono);font-size:11px;color:var(--green);background:var(--gdim);border:1px solid var(--gborder);padding:4px 10px;border-radius:4px;margin-bottom:1rem}
.page-tag::before{content:'';width:6px;height:6px;border-radius:50%;background:var(--green)}
.page-header h1{font-size:2rem;font-weight:600;line-height:1.2;margin-bottom:.5rem}
.page-header p{font-size:.95rem;color:var(--muted2);max-width:480px;line-height:1.7}

/* ── STATS ────────────────────────────────────────────────────── */
.stats{display:grid;grid-template-columns:repeat(3,1fr);border:1px solid var(--border);border-radius:8px;background:var(--bg2);overflow:hidden}
.stat{padding:1.5rem 2rem;border-right:1px solid var(--border)}
.stat:last-child{border-right:none}
.stat-num{font-size:2rem;font-weight:600;color:var(--green);line-height:1;margin-bottom:.35rem;font-family:var(--mono)}
.stat-label{font-size:.82rem;color:var(--muted2)}

/* ── CTA BAR ─────────────────────────────────────────────────── */
.cta-bar{background:var(--bg2);border:1px solid var(--border);border-radius:8px;padding:2.5rem;display:flex;align-items:center;justify-content:space-between;gap:2rem;margin-top:4rem;flex-wrap:wrap}
.cta-bar h3{font-size:1.3rem;font-weight:600;margin-bottom:.4rem}
.cta-bar p{font-size:.88rem;color:var(--muted2)}

/* ── INFO BOX ────────────────────────────────────────────────── */
.info-box{background:var(--bg2);border:1px solid var(--border);border-left:3px solid var(--green);border-radius:0 6px 6px 0;padding:.9rem 1.1rem;margin-bottom:1.5rem;font-size:.88rem;color:var(--muted2);line-height:1.7}

/* ── FOOTER ──────────────────────────────────────────────────── */
footer{border-top:1px solid var(--border);padding:1.5rem 2rem;display:flex;align-items:center;justify-content:space-between;font-size:12px;color:var(--muted);font-family:var(--mono)}

/* ── REVEAL ANIMATION ────────────────────────────────────────── */
.reveal{opacity:0;transform:translateY(16px);transition:opacity .6s ease,transform .6s ease}
.reveal.in{opacity:1;transform:none}

/* ── FORM ELEMENTS ───────────────────────────────────────────── */
.form-group{margin-bottom:1.25rem}
.form-label{display:block;font-family:var(--mono);font-size:10px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin-bottom:.5rem}
.form-input,.form-textarea,.form-select{width:100%;background:var(--bg3);border:1px solid var(--border2);border-radius:4px;padding:10px 14px;font-family:var(--sans);font-size:14px;color:var(--text);outline:none;transition:border-color .2s}
.form-input:focus,.form-textarea:focus,.form-select:focus{border-color:var(--green)}
.form-textarea{resize:vertical;min-height:100px;line-height:1.6}
.form-select{cursor:pointer;appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%239A9AA8' fill='none' stroke-width='1.5'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 12px center}
.form-tags{display:flex;flex-wrap:wrap;gap:6px;margin-top:.5rem}
.form-tag{padding:4px 10px;background:var(--gdim);color:var(--green);border:1px solid var(--gborder);border-radius:3px;font-family:var(--mono);font-size:11px;display:flex;align-items:center;gap:6px;cursor:pointer}
.form-tag .tag-remove{font-size:14px;line-height:1;opacity:.6;transition:opacity .2s}
.form-tag .tag-remove:hover{opacity:1}

/* ── LOADING SPINNER ─────────────────────────────────────────── */
.spinner{display:inline-block;width:16px;height:16px;border:2px solid var(--border2);border-top-color:var(--green);border-radius:50%;animation:spin .6s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.loading-overlay{display:flex;align-items:center;justify-content:center;padding:3rem;color:var(--muted);font-size:.9rem;gap:10px}

/* ── TABS (generic) ──────────────────────────────────────────── */
.tabs{display:flex;border-bottom:1px solid var(--border);margin-bottom:1.5rem}
.tab{padding:.7rem 1.1rem;font-size:13px;color:var(--muted2);cursor:pointer;border-bottom:2px solid transparent;margin-bottom:-1px;transition:all .2s}
.tab.active{color:var(--green);border-bottom-color:var(--green)}
.tab:hover:not(.active){color:var(--text)}

/* ── EMPTY STATE ─────────────────────────────────────────────── */
.empty-state{text-align:center;padding:3rem 2rem;color:var(--muted)}
.empty-state p{font-size:.9rem;margin-bottom:1rem}

/* ── RESPONSIVE ──────────────────────────────────────────────── */
@media(max-width:768px){
  .stats{grid-template-columns:1fr}
  .stat{border-right:none;border-bottom:1px solid var(--border)}
  .stat:last-child{border-bottom:none}
  .ch-board-hdr,.ch-board-header,.ch-row{grid-template-columns:36px 1fr 90px}
  .ch-col:nth-child(n+4),.ch-col-label:nth-child(n+4),
  .ch-row>*:nth-child(n+4){display:none}
  .container{padding:0 1.25rem}
  nav{padding:0 1.25rem}
  .page-header-inner{flex-direction:column}
  .nav-tabs a{padding:8px 10px;font-size:12px}
}