/* =============================================================================
   Architect.NET — Dark Tech Design System
   Cyber / Terminal aesthetic: deep space + neon cyan + monospace
   ============================================================================= */

/* ── Design Tokens ─────────────────────────────────────────────────────────── */
:root {
    --bg-void:      #060b14;
    --bg-deep:      #080e1b;
    --bg-surface:   #0d1628;
    --bg-elevated:  #111e36;

    --border:       rgba(0, 212, 200, 0.12);
    --border-hover: rgba(0, 212, 200, 0.4);
    --border-dim:   rgba(255, 255, 255, 0.06);

    --cyan:         #00d4c8;
    --cyan-dim:     rgba(0, 212, 200, 0.12);
    --cyan-glow:    0 0 20px rgba(0, 212, 200, 0.35), 0 0 40px rgba(0, 212, 200, 0.15);
    --green:        #39ff84;
    --green-glow:   0 0 16px rgba(57, 255, 132, 0.3);
    --yellow:       #fbbf24;
    --red:          #ff4d4f;

    --text-bright:  #e8f0fe;
    --text-primary: #c9d8f0;
    --text-muted:   #5e7a9e;
    --text-dim:     #3a5070;

    --font-sans:    'Inter', system-ui, -apple-system, sans-serif;
    --font-mono:    'JetBrains Mono', 'Fira Code', 'Cascadia Code', Consolas, monospace;

    --radius-sm:    6px;
    --radius:       10px;
    --radius-lg:    16px;
    --radius-xl:    22px;

    --shadow-glow:  0 0 0 1px rgba(0,212,200,0.2), 0 8px 32px rgba(0,0,0,0.6);
    --shadow-deep:  0 20px 60px rgba(0,0,0,0.7);
    --ease-out:     cubic-bezier(0.16, 1, 0.3, 1);
}

/* ── Reset ─────────────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

/* ── Custom scrollbar ──────────────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg-deep); }
::-webkit-scrollbar-thumb { background: rgba(0,212,200,0.2); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: rgba(0,212,200,0.4); }

/* ── Base ──────────────────────────────────────────────────────────────────── */
html, body {
    height: 100%;
    font-family: var(--font-sans);
    background-color: var(--bg-void);
    color: var(--text-primary);
    font-size: 15px;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
}

/* Animated grid background */
body::before {
    content: '';
    position: fixed; inset: 0;
    background-image:
        linear-gradient(rgba(0,212,200,0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0,212,200,0.03) 1px, transparent 1px);
    background-size: 40px 40px;
    pointer-events: none; z-index: 0;
}

/* Ambient top glow */
body::after {
    content: '';
    position: fixed; top: -20%; left: 50%; transform: translateX(-50%);
    width: 80vw; height: 60vh;
    background: radial-gradient(ellipse at center, rgba(0,212,200,0.05) 0%, rgba(167,139,250,0.03) 40%, transparent 70%);
    pointer-events: none; z-index: 0;
}

a { color: var(--cyan); text-decoration: none; transition: color .2s; }
a:hover { color: #fff; text-decoration: none; }

code {
    font-family: var(--font-mono); font-size: 0.88em;
    background: var(--bg-elevated); padding: 2px 7px;
    border-radius: 4px; color: var(--cyan); border: 1px solid var(--border);
}
pre {
    background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius); padding: 1.1rem; overflow-x: auto;
    margin: 0.75rem 0; font-family: var(--font-mono); font-size: 0.88em;
}
pre code { background: none; padding: 0; color: var(--text-primary); border: none; }
strong { color: var(--text-bright); }
h1, h2, h3, h4 { color: var(--text-bright); font-weight: 700; }

/* ── App layout ────────────────────────────────────────────────────────────── */
.app-layout { display: flex; flex-direction: column; min-height: 100vh; position: relative; z-index: 1; }

/* ── Header ────────────────────────────────────────────────────────────────── */
.app-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 0 2rem; height: 56px;
    background: rgba(8,14,27,0.92);
    border-bottom: 1px solid var(--border);
    backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
    position: sticky; top: 0; z-index: 100; flex-shrink: 0;
}
.app-header::after {
    content: ''; position: absolute; bottom: -1px; left: 50%; transform: translateX(-50%);
    width: 40%; height: 1px;
    background: linear-gradient(90deg, transparent, var(--cyan), transparent);
    opacity: 0.4;
}

.app-brand {
    font-family: var(--font-mono); font-size: 1.15rem; font-weight: 700;
    color: var(--text-bright); letter-spacing: -0.5px;
    display: flex; align-items: center; gap: 2px;
}
.app-brand::before { content: '> '; color: var(--cyan); opacity: 0.8; white-space: pre; }
.brand-dot { color: var(--cyan); }

.app-nav { display: flex; align-items: center; gap: 0.25rem; }

.nav-link {
    color: var(--text-muted); font-size: 0.88rem; font-weight: 500;
    padding: 5px 12px; border-radius: var(--radius-sm);
    transition: color .2s, background .2s;
}
.nav-link:hover { color: var(--text-bright); background: rgba(255,255,255,0.04); text-decoration: none; }

.nav-user {
    color: var(--cyan); font-family: var(--font-mono); font-size: 0.82rem;
    padding: 4px 12px; border-radius: var(--radius-sm);
    background: var(--cyan-dim); border: 1px solid var(--border);
}
.nav-logout-form { display: inline; }
.nav-logout { background: none; border: none; cursor: pointer; font-family: var(--font-sans); }

.nav-register {
    color: var(--bg-void) !important; background: var(--cyan);
    border-radius: var(--radius-sm); font-weight: 600; padding: 5px 14px;
    transition: background .2s, box-shadow .2s !important;
}
.nav-register:hover { background: #00f5e8; box-shadow: var(--cyan-glow); color: var(--bg-void) !important; }

/* ── Main ──────────────────────────────────────────────────────────────────── */
.app-main { flex: 1; padding: 2rem; overflow: auto; position: relative; z-index: 1; }

/* ── Home hero ─────────────────────────────────────────────────────────────── */
.home-hero { text-align: center; padding: 4rem 1rem 3rem; position: relative; }

.hero-title {
    font-family: var(--font-mono);
    font-size: clamp(2.8rem, 7vw, 5rem);
    font-weight: 700; color: var(--text-bright);
    letter-spacing: -0.04em; line-height: 1; margin-bottom: 1rem;
}
.hero-dot { color: var(--cyan); text-shadow: var(--cyan-glow); }

.hero-subtitle {
    color: var(--text-muted); font-size: 1rem;
    max-width: 500px; margin: 0 auto; line-height: 1.7;
}

/* ── Category sections ─────────────────────────────────────────────────────── */
.category-section { max-width: 1080px; margin: 0 auto 2.5rem; padding: 0 0.5rem; }

.category-heading {
    font-family: var(--font-mono); font-size: 0.75rem; font-weight: 600;
    text-transform: uppercase; letter-spacing: 0.15em;
    color: var(--text-dim); margin-bottom: 1rem;
    display: flex; align-items: center; gap: 0.75rem;
}
.category-heading::before { content: '//'; color: var(--cyan); opacity: 0.5; }
.category-heading::after { content: ''; flex: 1; height: 1px; background: var(--border); }

/* ── Challenge cards ───────────────────────────────────────────────────────── */
.challenges-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 1rem; }
.challenge-card-wrapper { position: relative; }

.challenge-card {
    display: block; background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius-lg); padding: 1.4rem 1.5rem;
    color: var(--text-primary);
    transition: border-color .25s var(--ease-out), transform .25s var(--ease-out), box-shadow .25s var(--ease-out);
    position: relative; overflow: hidden; cursor: pointer;
    height: 100%;
}
.challenge-card::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0; height: 1px;
    background: linear-gradient(90deg, transparent 0%, var(--cyan) 50%, transparent 100%);
    opacity: 0; transition: opacity .3s;
}
.challenge-card:hover {
    border-color: var(--border-hover); transform: translateY(-3px);
    box-shadow: var(--shadow-glow); text-decoration: none; color: var(--text-primary);
}
.challenge-card:hover::before { opacity: 0.6; }

.locked-card {
    background: var(--bg-deep); border: 1px solid var(--border-dim);
    border-radius: var(--radius-lg); padding: 1.4rem 1.5rem;
    opacity: 0.45; cursor: not-allowed; position: relative;
}
.lock-icon { font-size: 1.2rem; margin-bottom: 0.5rem; opacity: 0.4; }
.card-unlock-hint { font-size: 0.78rem; color: var(--text-dim); font-style: italic; }

.card-badge {
    display: inline-block; font-family: var(--font-mono);
    font-size: 0.68rem; font-weight: 600; padding: 2px 9px;
    border-radius: 20px; text-transform: uppercase;
    letter-spacing: .08em; margin-bottom: 0.6rem;
}
.card-badge.beginner  { background: rgba(57,255,132,0.08); color: var(--green); border: 1px solid rgba(57,255,132,0.22); }
.card-badge.intermediate { background: rgba(251,191,36,0.08); color: var(--yellow); border: 1px solid rgba(251,191,36,0.22); }
.card-badge.advanced  { background: rgba(255,77,79,0.08); color: var(--red); border: 1px solid rgba(255,77,79,0.22); }

.card-category {
    font-size: 0.72rem; color: var(--text-dim); font-family: var(--font-mono);
    letter-spacing: 0.06em; margin-bottom: 0.4rem; text-transform: uppercase;
}
.card-title { font-size: 1.05rem; font-weight: 600; color: var(--text-bright); margin-bottom: 0.5rem; line-height: 1.35; }
.card-rules { font-size: 0.78rem; color: var(--text-muted); font-family: var(--font-mono); margin-bottom: 0.75rem; }

.card-footer { display: flex; align-items: center; justify-content: space-between; }

.card-completed {
    font-size: 0.75rem; font-weight: 600; color: var(--green);
    font-family: var(--font-mono); display: flex; align-items: center; gap: 5px;
}
.card-completed::before { content: '●'; font-size: 0.5rem; animation: pulse-green 2s infinite; }
@keyframes pulse-green { 0%, 100% { opacity: 1; } 50% { opacity: 0.3; } }

.card-links { display: flex; align-items: center; gap: 0.5rem; margin-left: auto; }
.card-arrow { color: var(--text-dim); font-size: 1rem; transition: color .2s, transform .2s; }
.challenge-card:hover .card-arrow { color: var(--cyan); transform: translateX(3px); }
.card-leaderboard { font-size: 0.9rem; opacity: 0.35; transition: opacity .2s; }
.card-leaderboard:hover { opacity: 1; }

/* ── Challenge page layout ─────────────────────────────────────────────────── */
.challenge-layout {
    display: grid;
    grid-template-columns: 360px 1fr;
    gap: 1.25rem;
    height: calc(100vh - 56px - 4rem);
    overflow: hidden;
    transition: grid-template-columns .3s var(--ease-out);
}

/* 3-column variant: briefing | editor | score */
.challenge-layout.has-score {
    grid-template-columns: 300px 1fr 320px;
}

.panel-left { overflow-y: auto; display: flex; flex-direction: column; gap: 1rem; padding-right: 0.25rem; }
.panel-right {
    display: flex; flex-direction: column; overflow: hidden;
    background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
}

/* Score / curveball panel (3rd column) */
.panel-score {
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    padding-left: 0.25rem;
    animation: slide-in-right .35s var(--ease-out);
}

@keyframes slide-in-right {
    from { opacity: 0; transform: translateX(18px); }
    to   { opacity: 1; transform: translateX(0); }
}

.back-link {
    display: inline-flex; align-items: center; gap: 6px;
    color: var(--text-muted); font-size: 0.82rem; font-family: var(--font-mono);
    padding: 5px 10px; border-radius: var(--radius-sm);
    border: 1px solid transparent; transition: color .2s, border-color .2s;
}
.back-link:hover { color: var(--cyan); border-color: var(--border); background: var(--cyan-dim); text-decoration: none; }

.challenge-meta { display: flex; gap: 0.5rem; align-items: center; flex-wrap: wrap; }

.badge-diff { font-family: var(--font-mono); font-size: 0.68rem; font-weight: 600; padding: 2px 9px; border-radius: 20px; text-transform: uppercase; letter-spacing: .08em; }
.badge-diff.beginner    { background: rgba(57,255,132,0.08); color: var(--green); border: 1px solid rgba(57,255,132,0.22); }
.badge-diff.intermediate{ background: rgba(251,191,36,0.08); color: var(--yellow); border: 1px solid rgba(251,191,36,0.22); }
.badge-diff.advanced    { background: rgba(255,77,79,0.08); color: var(--red); border: 1px solid rgba(255,77,79,0.22); }

.badge-cat {
    font-family: var(--font-mono); font-size: 0.72rem; color: var(--text-muted);
    background: var(--bg-elevated); border: 1px solid var(--border); padding: 2px 9px; border-radius: 20px;
}

.challenge-title { font-size: 1.4rem; font-weight: 700; color: var(--text-bright); line-height: 1.3; margin: 0.6rem 0 0.25rem; }

/* ── Briefing ──────────────────────────────────────────────────────────────── */
.briefing-panel { background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; }
.briefing-header {
    display: flex; align-items: center; gap: 0.5rem;
    padding: 0.65rem 1rem; background: var(--bg-elevated); border-bottom: 1px solid var(--border);
    font-size: 0.75rem; font-weight: 600; font-family: var(--font-mono);
    color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.1em;
}
.briefing-header::before { content: '//'; color: var(--cyan); opacity: 0.5; }
.briefing-body { padding: 1rem; color: var(--text-muted); font-size: 0.88rem; line-height: 1.7; }
.briefing-body p { margin-bottom: 0.6rem; }
.briefing-body ul { padding-left: 1.2rem; margin-bottom: 0.6rem; }
.briefing-body li { margin-bottom: 0.25rem; }

/* ── Editor toolbar ────────────────────────────────────────────────────────── */
.editor-toolbar {
    display: flex; align-items: center; justify-content: space-between;
    padding: 0.55rem 1rem; background: var(--bg-elevated);
    border-bottom: 1px solid var(--border); border-radius: var(--radius-lg) var(--radius-lg) 0 0; flex-shrink: 0;
}
.editor-label {
    font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-dim);
    font-weight: 600; letter-spacing: 0.1em; text-transform: uppercase;
    display: flex; align-items: center; gap: 8px;
}
.editor-label::before { content: '● ● ●'; font-size: 0.45rem; letter-spacing: 4px; color: rgba(255,255,255,0.12); }
.editor-actions { display: flex; gap: 0.5rem; align-items: center; }

.btn-reset {
    background: transparent; border: 1px solid var(--border); color: var(--text-muted);
    padding: 5px 13px; border-radius: var(--radius-sm); font-size: 0.8rem;
    font-family: var(--font-mono); cursor: pointer; transition: border-color .15s, color .15s, background .15s;
}
.btn-reset:hover:not(:disabled) { border-color: var(--border-hover); color: var(--text-bright); background: rgba(255,255,255,0.04); }
.btn-reset:disabled { opacity: 0.35; cursor: not-allowed; }

.btn-submit {
    background: var(--cyan); border: 1px solid var(--cyan); color: var(--bg-void);
    padding: 5px 18px; border-radius: var(--radius-sm); font-size: 0.84rem; font-weight: 700;
    font-family: var(--font-mono); cursor: pointer; transition: background .2s, box-shadow .2s;
    letter-spacing: 0.03em;
}
.btn-submit:hover:not(:disabled) { background: #00f5e8; box-shadow: var(--cyan-glow); }
.btn-submit:disabled { opacity: 0.4; cursor: not-allowed; }

.editor-container { flex: 1; min-height: 0; }
.editor-container .monaco-editor-container,
.editor-container .monaco-editor-container > section { height: 100% !important; }
.editor-error { padding: 0.5rem 1rem; font-size: 0.8rem; font-family: var(--font-mono); color: var(--red); background: rgba(255,77,79,0.06); border-top: 1px solid rgba(255,77,79,0.2); }

/* ── Score panel ───────────────────────────────────────────────────────────── */
.score-panel {
    background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius-lg); padding: 1.1rem;
    animation: slide-up .3s var(--ease-out);
}
@keyframes slide-up { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }

.score-header { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 0.75rem; }
.score-total { display: flex; align-items: baseline; gap: 3px; }
.score-number { font-size: 2.2rem; font-weight: 800; font-family: var(--font-mono); line-height: 1; }
.score-max { font-size: 1rem; color: var(--text-dim); font-family: var(--font-mono); }
.score-pct { font-size: 1.2rem; font-weight: 700; font-family: var(--font-mono); }

.score-excellent .score-number, .score-excellent .score-pct { color: var(--green); text-shadow: var(--green-glow); }
.score-good      .score-number, .score-good      .score-pct { color: var(--cyan); }
.score-average   .score-number, .score-average   .score-pct { color: var(--yellow); }
.score-poor      .score-number, .score-poor      .score-pct { color: var(--red); }

.score-bar-wrap { height: 4px; background: var(--bg-elevated); border-radius: 2px; overflow: hidden; margin-bottom: 0.9rem; }
.score-bar {
    height: 100%; border-radius: 2px;
    background: linear-gradient(90deg, var(--cyan), var(--green));
    box-shadow: 0 0 8px rgba(0,212,200,0.5); transition: width .6s var(--ease-out);
}

.rules-list { display: flex; flex-direction: column; gap: 3px; }
.rule-row {
    display: flex; align-items: flex-start; gap: 0.5rem;
    font-size: 0.8rem; padding: 5px 8px; border-radius: var(--radius-sm); font-family: var(--font-mono);
}
.rule-pass { background: rgba(57,255,132,0.05); border-left: 2px solid rgba(57,255,132,0.3); }
.rule-fail  { background: rgba(255,77,79,0.05);  border-left: 2px solid rgba(255,77,79,0.3); }
.rule-icon { flex-shrink: 0; font-weight: 700; }
.rule-pass .rule-icon { color: var(--green); }
.rule-fail .rule-icon { color: var(--red); }
.rule-id { flex-shrink: 0; color: var(--text-dim); font-size: 0.72rem; min-width: 64px; }
.rule-desc { flex: 1; color: var(--text-muted); font-family: var(--font-sans); font-size: 0.8rem; }
.rule-pts { flex-shrink: 0; font-weight: 700; }
.pts-pos { color: var(--green); }
.pts-neg { color: var(--red); }

/* ── Curveball ─────────────────────────────────────────────────────────────── */
.curveball-panel {
    background: var(--bg-surface); border: 1px solid rgba(251,191,36,0.3);
    border-radius: var(--radius-lg); 
    /* overflow: hidden; */
    animation: slide-up .35s var(--ease-out);
    box-shadow: 0 0 24px rgba(251,191,36,0.06);
}
.curveball-header {
    display: flex; align-items: center; gap: 0.5rem;
    padding: 0.7rem 1rem; cursor: pointer; font-weight: 700;
    color: var(--yellow); font-size: 0.85rem; font-family: var(--font-mono);
    background: rgba(251,191,36,0.06); user-select: none;
    transition: background .15s; border-bottom: 1px solid rgba(251,191,36,0.15);
}
.curveball-header:hover { background: rgba(251,191,36,0.1); }
.curveball-icon { font-size: 1rem; }
.curveball-hint { font-size: 0.75rem; color: rgba(251,191,36,0.4); font-weight: 400; margin-left: auto; }
.curveball-body { padding: 1rem; font-size: 0.87rem; color: var(--text-muted); line-height: 1.65; }
.curveball-body p { margin-bottom: 0.6rem; }

/* ── Auth pages ────────────────────────────────────────────────────────────── */
.auth-page { display: flex; align-items: center; justify-content: center; min-height: calc(100vh - 56px); padding: 2rem; }

.auth-card {
    background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius-xl); padding: 2.5rem 2.25rem;
    width: 100%; max-width: 400px;
    box-shadow: var(--shadow-deep);
    position: relative; overflow: hidden; animation: slide-up .4s var(--ease-out);
}
.auth-card::before {
    content: ''; position: absolute; top: -1px; left: -1px; right: -1px; height: 1px;
    background: linear-gradient(90deg, transparent 10%, var(--cyan) 50%, transparent 90%);
    opacity: 0.6;
}

.auth-back { display: inline-flex; align-items: center; gap: 5px; color: var(--text-muted); font-size: 0.82rem; font-family: var(--font-mono); margin-bottom: 1.5rem; transition: color .2s; }
.auth-back:hover { color: var(--cyan); text-decoration: none; }

.auth-title { font-family: var(--font-mono); font-size: 1.6rem; font-weight: 700; color: var(--text-bright); margin-bottom: 0.25rem; letter-spacing: -0.03em; }
.auth-title::after { content: '_'; color: var(--cyan); animation: blink 1.1s step-end infinite; }
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }

.auth-error { background: rgba(255,77,79,0.08); border: 1px solid rgba(255,77,79,0.3); border-radius: var(--radius-sm); color: var(--red); font-size: 0.84rem; padding: 0.65rem 0.9rem; margin-bottom: 1rem; font-family: var(--font-mono); }

.auth-form { display: flex; flex-direction: column; gap: 1rem; margin-top: 1.5rem; }

.form-field { display: flex; flex-direction: column; gap: 0.4rem; }
.form-field label { font-size: 0.78rem; font-weight: 600; font-family: var(--font-mono); color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.08em; }
.form-field input {
    background: var(--bg-elevated); border: 1px solid var(--border);
    border-radius: var(--radius-sm); color: var(--text-bright);
    font-family: var(--font-mono); font-size: 0.9rem; padding: 10px 13px;
    outline: none; transition: border-color .2s, box-shadow .2s; width: 100%;
}
.form-field input::placeholder { color: var(--text-dim); }
.form-field input:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(0,212,200,0.1); }

.btn-auth {
    width: 100%; background: var(--cyan); border: none; border-radius: var(--radius-sm);
    color: var(--bg-void); font-size: 0.9rem; font-weight: 700; font-family: var(--font-mono);
    padding: 11px; cursor: pointer; transition: background .2s, box-shadow .2s;
    letter-spacing: 0.05em; margin-top: 0.5rem;
}
.btn-auth:hover { background: #00f5e8; box-shadow: var(--cyan-glow); }

.auth-switch { text-align: center; font-size: 0.84rem; color: var(--text-dim); margin-top: 1.25rem; }
.auth-switch a { color: var(--cyan); font-weight: 600; }

/* ── Leaderboard ───────────────────────────────────────────────────────────── */
.leaderboard-page { max-width: 680px; margin: 0 auto; padding: 0 0.5rem; }
.leaderboard-header { margin-bottom: 1.5rem; }
.leaderboard-title { font-family: var(--font-mono); font-size: 1.6rem; font-weight: 700; color: var(--text-bright); margin-bottom: 0.3rem; }
.leaderboard-subtitle { font-size: 0.85rem; color: var(--text-dim); font-family: var(--font-mono); }

.leaderboard-table { width: 100%; border-collapse: separate; border-spacing: 0 4px; }
.leaderboard-table th { font-family: var(--font-mono); font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text-dim); padding: 0 1rem 0.75rem; text-align: left; }
.leaderboard-table th:last-child { text-align: right; }

.leaderboard-row { background: var(--bg-surface); border: 1px solid var(--border); transition: border-color .2s, background .2s; }
.leaderboard-row:hover { background: var(--bg-elevated); border-color: var(--border-hover); }
.leaderboard-row td { padding: 0.85rem 1rem; font-size: 0.88rem; }
.leaderboard-row td:first-child { border-radius: var(--radius-sm) 0 0 var(--radius-sm); }
.leaderboard-row td:last-child  { border-radius: 0 var(--radius-sm) var(--radius-sm) 0; }

.rank-gold   { background: rgba(251,191,36,0.06) !important; border-color: rgba(251,191,36,0.25) !important; }
.rank-silver { background: rgba(200,215,230,0.05) !important; border-color: rgba(200,215,230,0.15) !important; }
.rank-bronze { background: rgba(180,120,70,0.05) !important; border-color: rgba(180,120,70,0.2) !important; }

.rank-num { font-family: var(--font-mono); font-size: 0.82rem; color: var(--text-dim); min-width: 32px; display: inline-block; }
.rank-gold   .rank-num { color: var(--yellow); }
.rank-silver .rank-num { color: #c8d7e6; }
.rank-bronze .rank-num { color: #b47846; }

.lb-username { font-family: var(--font-mono); font-size: 0.88rem; color: var(--text-primary); font-weight: 600; }
.lb-score    { font-family: var(--font-mono); font-weight: 700; font-size: 0.95rem; text-align: right; color: var(--cyan); }
.lb-pct      { font-family: var(--font-mono); font-size: 0.8rem; color: var(--text-muted); text-align: right; padding-right: 0.5rem; }
.lb-date     { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-dim); text-align: right; }

.leaderboard-empty { text-align: center; padding: 3rem 1rem; color: var(--text-dim); font-family: var(--font-mono); font-size: 0.9rem; }
.leaderboard-empty a { color: var(--cyan); }

/* ── Loading ───────────────────────────────────────────────────────────────── */
.loading-state { display: flex; align-items: center; justify-content: center; padding: 3rem; color: var(--text-dim); font-family: var(--font-mono); font-size: 0.85rem; gap: 0.75rem; }
.loading-state::before { content: ''; width: 16px; height: 16px; border: 2px solid var(--border); border-top-color: var(--cyan); border-radius: 50%; animation: spin .7s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Not found ─────────────────────────────────────────────────────────────── */
.not-found { text-align: center; padding: 5rem 1rem; color: var(--text-dim); font-family: var(--font-mono); }
.not-found h2 { color: var(--text-bright); font-size: 1.4rem; margin-bottom: 0.75rem; }

/* ── Submit login gate ──────────────────────────────────────────────────────── */
.btn-submit-login {
    display: inline-flex; align-items: center; gap: 0.4rem;
    text-decoration: none; opacity: 0.75;
    border: 1px dashed var(--border-hover);
    background: transparent !important;
    color: var(--text-muted) !important;
}
.btn-submit-login:hover { opacity: 1; color: var(--cyan) !important; border-color: var(--cyan); background: var(--cyan-dim) !important; }

/* ── Profile page ────────────────────────────────────────────────────────────── */
.profile-page { max-width: 760px; margin: 0 auto; padding: 0 0.5rem; }

.profile-header { display: flex; align-items: center; gap: 1.25rem; margin-bottom: 2.5rem; }
.profile-avatar {
    width: 64px; height: 64px; border-radius: 50%;
    background: var(--cyan-dim); border: 2px solid rgba(0,212,200,0.4);
    display: flex; align-items: center; justify-content: center;
    font-family: var(--font-mono); font-size: 1.6rem; font-weight: 700;
    color: var(--cyan); flex-shrink: 0;
}
.profile-name { font-family: var(--font-mono); font-size: 1.5rem; font-weight: 700; color: var(--text-bright); margin: 0 0 0.25rem; }
.profile-meta { display: flex; gap: 0.5rem; align-items: center; margin: 0; }
.profile-stat { font-family: var(--font-mono); font-size: 0.8rem; color: var(--text-dim); }
.profile-stat-sep { color: var(--text-dim); }

.profile-empty { text-align: center; padding: 3rem 1rem; color: var(--text-dim); font-family: var(--font-mono); }

.profile-challenges { display: flex; flex-direction: column; gap: 1.25rem; }

.profile-challenge-card {
    background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius-lg); padding: 1.25rem 1.5rem;
    transition: border-color .2s;
}
.profile-challenge-card:hover { border-color: var(--border-hover); }

.profile-card-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 1rem; gap: 0.75rem; }
.profile-card-title { font-family: var(--font-mono); font-size: 0.95rem; font-weight: 600; color: var(--text-bright); }
.profile-badge-done { margin-left: 0.6rem; font-size: 0.72rem; font-family: var(--font-mono); color: var(--green); background: rgba(57,255,132,0.1); border: 1px solid rgba(57,255,132,0.3); border-radius: 4px; padding: 2px 7px; }
.profile-card-link { font-family: var(--font-mono); font-size: 0.78rem; color: var(--cyan); white-space: nowrap; text-decoration: none; flex-shrink: 0; }
.profile-card-link:hover { text-decoration: underline; }

.profile-best-score { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 0.85rem; }
.profile-score-label { font-family: var(--font-mono); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-dim); }
.profile-score-value { font-family: var(--font-mono); font-weight: 700; color: var(--cyan); }
.profile-score-pct { font-family: var(--font-mono); font-size: 0.8rem; padding: 2px 8px; border-radius: 4px; }
.pct-pass { color: var(--green); background: rgba(57,255,132,0.08); }
.pct-fail { color: var(--text-dim); background: var(--bg-deep); }

.profile-history { display: flex; flex-direction: column; gap: 4px; margin-bottom: 0.85rem; }
.profile-history-row { display: grid; grid-template-columns: 100px 1fr 60px; align-items: center; gap: 0.6rem; }
.history-date { font-family: var(--font-mono); font-size: 0.72rem; color: var(--text-dim); }
.history-bar-wrap { height: 4px; background: var(--bg-deep); border-radius: 2px; overflow: hidden; }
.history-bar { height: 100%; background: var(--cyan); border-radius: 2px; transition: width .4s var(--ease-out); }
.history-score { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-muted); text-align: right; }

.profile-card-footer { display: flex; justify-content: space-between; align-items: center; border-top: 1px solid var(--border); padding-top: 0.75rem; margin-top: 0.25rem; }
.profile-attempts { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-dim); }
.profile-lb-link { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-muted); text-decoration: none; }
.profile-lb-link:hover { color: var(--cyan); }

/* ── Global Leaderboard Index ────────────────────────────────────────────────── */
.leaderboard-index { max-width: 900px; margin: 0 auto; padding: 0 0.5rem; }
.leaderboard-index-hero { text-align: center; margin-bottom: 2.5rem; }
.leaderboard-index-title { font-family: var(--font-mono); font-size: 2rem; font-weight: 700; color: var(--text-bright); margin-bottom: 0.3rem; }

.lb-index-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1.25rem; }

.lb-index-card {
    background: var(--bg-surface); border: 1px solid var(--border);
    border-radius: var(--radius-lg); padding: 1.25rem;
    display: flex; flex-direction: column; gap: 0.75rem;
    transition: border-color .2s, box-shadow .2s;
}
.lb-index-card:hover { border-color: var(--border-hover); box-shadow: var(--cyan-glow); }

.lb-index-card-header { display: flex; justify-content: space-between; align-items: flex-start; gap: 0.5rem; }
.lb-index-card-title { font-family: var(--font-mono); font-size: 0.88rem; font-weight: 600; color: var(--text-bright); }

.lb-index-empty { font-family: var(--font-mono); font-size: 0.78rem; color: var(--text-dim); margin: 0; }

.lb-index-list { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 6px; }
.lb-index-entry { display: flex; align-items: center; gap: 0.6rem; }
.lb-index-medal {
    width: 22px; height: 22px; border-radius: 50%; flex-shrink: 0;
    display: flex; align-items: center; justify-content: center;
    font-family: var(--font-mono); font-size: 0.7rem; font-weight: 700;
}
.medal-gold   { background: rgba(251,191,36,0.15); color: var(--yellow); border: 1px solid rgba(251,191,36,0.4); }
.medal-silver { background: rgba(200,215,230,0.08); color: #c8d7e6; border: 1px solid rgba(200,215,230,0.2); }
.medal-bronze { background: rgba(180,120,70,0.08); color: #b47846; border: 1px solid rgba(180,120,70,0.25); }

.lb-index-player { font-family: var(--font-mono); font-size: 0.82rem; color: var(--text-primary); flex: 1; }
.lb-index-score  { font-family: var(--font-mono); font-size: 0.78rem; color: var(--cyan); }

.lb-index-view-all { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-muted); text-decoration: none; margin-top: auto; }
.lb-index-view-all:hover { color: var(--cyan); }

/* ── Responsive ────────────────────────────────────────────────────────────── */
@media (max-width: 1300px) {
    .challenge-layout.has-score { grid-template-columns: 260px 1fr 280px; }
}
@media (max-width: 1080px) {
    .challenge-layout,
    .challenge-layout.has-score { grid-template-columns: 1fr; height: auto; overflow: visible; }
    .panel-right { min-height: 500px; }
    .panel-score { padding-left: 0; }
}
@media (max-width: 800px) {
    .challenge-layout { grid-template-columns: 1fr; height: auto; }
    .panel-right { height: 480px; }
    .app-header { padding: 0 1rem; }
    .app-main { padding: 1rem; }
    .home-hero { padding: 2.5rem 0.5rem 1.5rem; }
    .hero-title { font-size: clamp(2rem, 10vw, 3.5rem); }
}

/* ── Accessibility ─────────────────────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

/* ── Blazor error UI ───────────────────────────────────────────────────────── */
#blazor-error-ui {
    background: rgba(255,77,79,0.1); border-top: 1px solid rgba(255,77,79,0.4);
    bottom: 0; display: none; left: 0; padding: 0.65rem 1.5rem;
    position: fixed; width: 100%; z-index: 1000;
    color: var(--red); font-size: 0.84rem; font-family: var(--font-mono);
    backdrop-filter: blur(8px);
}
#blazor-error-ui .reload { color: var(--cyan); font-weight: 600; margin-left: 0.5rem; }
#blazor-error-ui .dismiss { cursor: pointer; float: right; font-weight: 600; color: var(--text-muted); }