/* styles.css — SkillProof Lite design system
   Palette: bg #0A0A10, panel #14141F, violet #7C6AEF, blue #4A9EFF, green #34D399,
            text #ECECF3, muted #8B8B9E, border rgba(255,255,255,.08)
   Type: Space Grotesk (display) + Inter (body/UI) */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;600;700&family=Inter:wght@400;500;600&display=swap');

:root {
  --bg: #0A0A10;
  --panel: #14141F;
  --panel-2: #191926;
  --border: rgba(255,255,255,.08);
  --text: #ECECF3;
  --muted: #8B8B9E;
  --violet: #7C6AEF;
  --blue: #4A9EFF;
  --green: #34D399;
  --amber: #F5A623;
  --red: #F26D6D;
  --radius: 14px;
  --font-display: "Space Grotesk", "Inter", sans-serif;
  --font-body: "Inter", sans-serif;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { font-family: var(--font-display); font-weight: 600; margin: 0 0 8px; letter-spacing: -0.01em; }
h1 { font-size: 2rem; }
h3 { font-size: 1.05rem; color: var(--text); margin-top: 28px; }
p { margin: 0 0 12px; }
.muted { color: var(--muted); }
a { color: var(--blue); }

/* animated grid backdrop, confined to hero */
.grid-bg {
  position: absolute; inset: 0; z-index: 0;
  background-image:
    linear-gradient(to right, rgba(124,106,239,.08) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(124,106,239,.08) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 20%, black 40%, transparent 100%);
  animation: gridDrift 28s linear infinite;
}
@keyframes gridDrift { from { background-position: 0 0; } to { background-position: 84px 84px; } }

.orb {
  position: absolute; border-radius: 50%; filter: blur(60px); opacity: .35; z-index: 0;
}
.orb-1 { width: 380px; height: 380px; background: var(--violet); top: -120px; left: -80px; }
.orb-2 { width: 320px; height: 320px; background: var(--blue); top: 60px; right: -100px; }

/* nav */
.topnav {
  position: sticky; top: 0; z-index: 30;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 32px;
  background: rgba(10,10,16,.75);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.brand { font-family: var(--font-display); font-weight: 700; font-size: 1.05rem; }
.brand span { color: var(--violet); }
.nav-links { display: flex; gap: 4px; align-items: center; }
.navlink {
  background: none; border: none; color: var(--muted); font: inherit; font-size: .92rem;
  padding: 8px 14px; border-radius: 8px; cursor: pointer; transition: color .15s, background .15s;
}
.navlink:hover { color: var(--text); background: rgba(255,255,255,.04); }
.navlink.active { color: var(--text); background: var(--panel-2); }
.search-wrap { display: flex; align-items: center; gap: 8px; }
#search-input {
  background: var(--panel); border: 1px solid var(--border); color: var(--text);
  padding: 7px 12px; border-radius: 8px; font: inherit; font-size: .88rem; width: 200px;
}
.kbd-hint {
  font-size: .72rem; color: var(--muted); border: 1px solid var(--border);
  padding: 2px 6px; border-radius: 5px; font-family: var(--font-body);
}

/* hero */
.hero {
  position: relative; overflow: hidden;
  padding: 96px 32px 80px; text-align: center;
}
.hero-content { position: relative; z-index: 1; max-width: 640px; margin: 0 auto; }
.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.4rem); line-height: 1.08; margin-bottom: 18px;
}
.hero p.lead { font-size: 1.08rem; color: var(--muted); max-width: 480px; margin: 0 auto 30px; }
.hero-ctas { display: flex; gap: 12px; justify-content: center; }

.btn-primary {
  background: linear-gradient(135deg, var(--violet), var(--blue));
  color: #fff; border: none; padding: 11px 22px; border-radius: 9px;
  font: inherit; font-weight: 600; font-size: .93rem; cursor: pointer;
  box-shadow: 0 0 0 0 rgba(124,106,239,0); transition: box-shadow .2s, transform .15s;
}
.btn-primary:hover { box-shadow: 0 6px 24px rgba(124,106,239,.45); transform: translateY(-1px); }
.btn-ghost {
  background: var(--panel); color: var(--text); border: 1px solid var(--border);
  padding: 10px 20px; border-radius: 9px; font: inherit; font-size: .9rem; cursor: pointer;
  transition: border-color .15s, background .15s;
}
.btn-ghost:hover { border-color: rgba(255,255,255,.2); background: var(--panel-2); }

.hero-stats { display: flex; gap: 36px; justify-content: center; margin-top: 52px; position: relative; z-index: 1; }
.hero-stat { text-align: center; }
.hero-stat .num { display: block; font-family: var(--font-display); font-size: 1.6rem; font-weight: 700; color: var(--text); }
.hero-stat .lbl { font-size: .8rem; color: var(--muted); }

/* main container */
#app-main { max-width: 980px; margin: 0 auto; padding: 48px 32px 96px; min-height: 50vh; }

/* glass panel base */
.glass-panel {
  background: rgba(20,20,31,.6);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 24px;
  backdrop-filter: blur(10px);
}

/* challenge grid + cards */
.challenge-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; margin-top: 20px; }
.challenge-card {
  background: rgba(20,20,31,.55); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; cursor: pointer; transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
  backdrop-filter: blur(10px);
}
.challenge-card:hover, .challenge-card:focus-visible {
  transform: translateY(-4px);
  border-color: rgba(124,106,239,.4);
  box-shadow: 0 14px 36px rgba(0,0,0,.35), 0 0 0 1px rgba(124,106,239,.15);
  outline: none;
}
.challenge-card h3 { font-size: 1.02rem; margin: 10px 0 6px; }
.card-top { display: flex; justify-content: space-between; align-items: center; }
.card-desc { color: var(--muted); font-size: .87rem; margin-bottom: 14px; }
.card-foot { display: flex; justify-content: space-between; align-items: center; margin-top: 16px; }
.sub-count { font-size: .78rem; color: var(--muted); }
.btn-open { padding: 6px 14px; font-size: .82rem; }

.badge {
  font-size: .72rem; font-weight: 600; padding: 4px 10px; border-radius: 20px;
  border: 1px solid transparent;
}
.diff-beginner { background: rgba(52,211,153,.12); color: var(--green); border-color: rgba(52,211,153,.3); }
.diff-intermediate { background: rgba(245,166,35,.12); color: var(--amber); border-color: rgba(245,166,35,.3); }
.diff-advanced { background: rgba(242,109,109,.12); color: var(--red); border-color: rgba(242,109,109,.3); }

.xp-pill {
  font-size: .74rem; font-weight: 600; color: var(--violet);
  background: rgba(124,106,239,.12); padding: 4px 10px; border-radius: 20px;
}
.tag-row { display: flex; gap: 6px; flex-wrap: wrap; align-items: center; margin: 8px 0; }
.stack-tag {
  font-size: .76rem; font-weight: 600; color: var(--blue); background: rgba(74,158,255,.12);
  padding: 3px 9px; border-radius: 6px;
}
.tag { font-size: .76rem; color: var(--muted); background: rgba(255,255,255,.04); padding: 3px 9px; border-radius: 6px; }

.empty-state { text-align: center; padding: 60px 20px; color: var(--muted); }

/* detail / proof */
.detail-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 18px; }
.detail-desc { color: var(--muted); max-width: 640px; }
.verify-status { font-size: .78rem; color: var(--green); font-weight: 600; }

.submit-form { margin-top: 26px; display: flex; flex-direction: column; gap: 14px; }
.submit-form label { display: flex; flex-direction: column; gap: 6px; font-size: .85rem; color: var(--muted); }
.submit-form input, .submit-form textarea, .submit-form select {
  background: var(--panel-2); border: 1px solid var(--border); color: var(--text);
  padding: 10px 12px; border-radius: 8px; font: inherit; font-size: .92rem; resize: vertical;
}
.submit-form input:focus, .submit-form textarea:focus, .submit-form select:focus {
  outline: none; border-color: var(--violet);
}
.submit-form .btn-primary { align-self: flex-start; margin-top: 4px; }

.timeline-heading { margin-top: 34px; }
.timeline { display: flex; flex-direction: column; gap: 4px; margin-top: 12px; }
.timeline-item { display: flex; gap: 14px; padding: 14px 4px; border-bottom: 1px solid var(--border); cursor: pointer; }
.timeline-item:hover .timeline-body strong { color: var(--violet); }
.timeline-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--violet); margin-top: 6px; flex-shrink: 0; }
.timeline-row { display: flex; justify-content: space-between; gap: 12px; }
.timeline-body { flex: 1; }

.proof-hero { text-align: center; margin: 18px 0 22px; }
.proof-links { display: grid; gap: 10px; margin-bottom: 22px; }
.proof-link {
  display: flex; justify-content: space-between; gap: 12px; text-decoration: none;
  background: var(--panel); border: 1px solid var(--border); border-radius: 10px;
  padding: 14px 16px; color: var(--text); font-weight: 600; font-size: .9rem;
  transition: border-color .15s;
}
.proof-link:hover { border-color: rgba(124,106,239,.4); }
.proof-link .muted { font-weight: 400; }
.badge-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 20px; }
.achievement-badge {
  background: var(--panel-2); border: 1px solid var(--border); border-radius: 20px;
  padding: 7px 14px; font-size: .82rem;
}

/* dashboard */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 14px; margin: 22px 0 10px; }
.stat-card { text-align: left; }
.stat-label { display: block; font-size: .8rem; color: var(--muted); margin-bottom: 8px; }
.stat-value {
  font-family: var(--font-display); font-size: 2rem; font-weight: 700;
  background: linear-gradient(135deg, var(--violet), var(--blue));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}

/* leaderboard */
.leaderboard-table { margin-top: 18px; padding: 8px 20px; }
.lb-row {
  display: grid; grid-template-columns: 64px 1fr 110px 90px; align-items: center;
  padding: 12px 4px; border-bottom: 1px solid var(--border); font-size: .92rem;
}
.lb-row:last-child { border-bottom: none; }
.lb-head { color: var(--muted); font-size: .78rem; text-transform: none; }
.lb-rank { font-weight: 600; }
.lb-you { background: rgba(124,106,239,.08); border-radius: 8px; }

/* command palette */
#cmdk { position: fixed; inset: 0; z-index: 100; display: none; align-items: flex-start; justify-content: center; padding-top: 14vh; }
#cmdk.open { display: flex; }
#cmdk-backdrop { position: absolute; inset: 0; background: rgba(5,5,10,.65); backdrop-filter: blur(3px); }
.cmdk-box {
  position: relative; width: min(520px, 90vw); background: var(--panel);
  border: 1px solid var(--border); border-radius: 12px; overflow: hidden;
  box-shadow: 0 24px 60px rgba(0,0,0,.5);
}
#cmdk-input {
  width: 100%; background: transparent; border: none; border-bottom: 1px solid var(--border);
  color: var(--text); padding: 16px 18px; font: inherit; font-size: 1rem;
}
#cmdk-input:focus { outline: none; }
#cmdk-list { max-height: 320px; overflow-y: auto; padding: 6px; }
.cmdk-item { padding: 11px 14px; border-radius: 8px; cursor: pointer; font-size: .92rem; }
.cmdk-item:hover { background: var(--panel-2); color: var(--violet); }
.cmdk-empty { padding: 16px; color: var(--muted); font-size: .88rem; }

footer { text-align: center; padding: 28px; color: var(--muted); font-size: .82rem; border-top: 1px solid var(--border); }

@media (max-width: 720px) {
  .topnav { padding: 12px 16px; flex-wrap: wrap; gap: 10px; }
  #search-input { width: 140px; }
  .hero { padding: 64px 20px 56px; }
  #app-main { padding: 34px 18px 70px; }
  .hero-stats { gap: 22px; flex-wrap: wrap; }
  .lb-row { grid-template-columns: 44px 1fr 70px 70px; font-size: .84rem; }
}

@media (prefers-reduced-motion: reduce) {
  .grid-bg { animation: none; }
  .challenge-card, .btn-primary { transition: none; }
}