/* ==========================================================================
   LearnLens custom theme — layered on top of Bootstrap 5.
   Palette ported from the original Streamlit app's global CSS block.
   ========================================================================== */

:root {
    --ll-navy:        #0D2141;
    --ll-navy-light:  #17335c;
    --ll-slate:       #64748b;
    --ll-fog:         #A9BBCC;
    --ll-mist:        #C3CFDA;
    --ll-line:        #86A0B8;
    --ll-bg:          #F7F8FA;
    --ll-card-border: #e8e4de;

    --ll-novice:      #DC6B2F;
    --ll-developing:  #2F7DDC;
    --ll-proficient:  #2FA35C;

    --ll-radius:      14px;
    --ll-font-serif:  'DM Serif Display', Georgia, serif;
    --ll-font-sans:   'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

body {
    font-family: var(--ll-font-sans);
    background-color: var(--ll-bg);
    color: #1a2433;
}

h1, h2, h3, .ll-serif {
    font-family: var(--ll-font-serif);
    font-weight: 400;
    color: var(--ll-navy);
}

/* ── Navbar ────────────────────────────────────────────────────────────── */
.ll-navbar {
    background: linear-gradient(100deg, var(--ll-navy) 0%, var(--ll-navy-light) 100%);
    padding: 0.7rem 1.5rem;
    box-shadow: 0 4px 18px rgba(0, 0, 0, 0.16);
    position: relative;
    z-index: 10;
}
.ll-navbar .navbar-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    font-family: var(--ll-font-serif);
    color: #fff !important;
    font-size: 1.3rem;
    letter-spacing: 0.02em;
}
.ll-navbar-mark {
    display: inline-grid;
    place-items: center;
    width: 34px;
    height: 34px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.14);
    color: #fff;
    font-size: 1rem;
    flex: 0 0 auto;
}
.ll-navbar .nav-link {
    color: var(--ll-mist) !important;
    font-weight: 500;
    font-size: 0.88rem;
}
.ll-navbar .nav-link:hover,
.ll-navbar .nav-link.active {
    color: #fff !important;
}
.ll-navbar-user {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.35rem 0.85rem 0.35rem 0.4rem;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.08);
}
.ll-navbar-avatar {
    display: inline-grid;
    place-items: center;
    width: 26px;
    height: 26px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.18);
    color: #fff;
    font-size: 0.72rem;
    font-weight: 700;
    flex: 0 0 auto;
}
.ll-navbar-email {
    color: var(--ll-mist);
    font-size: 0.82rem;
    max-width: 220px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.ll-navbar-pill {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.45rem 0.9rem;
    border-radius: 999px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--ll-mist) !important;
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.16);
    transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
    text-decoration: none !important;
}
.ll-navbar-pill:hover,
.ll-navbar-pill:focus-visible {
    color: #fff !important;
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.3);
}
.ll-navbar-pill-signout {
    color: #fff !important;
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.22);
}
.ll-navbar-pill-signout:hover,
.ll-navbar-pill-signout:focus-visible {
    background: #fff;
    color: var(--ll-navy) !important;
    border-color: #fff;
}
@media (max-width: 991.98px) {
    .ll-navbar-user,
    .ll-navbar-pill {
        width: 100%;
        justify-content: flex-start;
    }
    .ll-navbar .navbar-nav {
        gap: 0.5rem;
        padding-top: 0.5rem;
    }
    .ll-navbar-email {
        max-width: none;
    }
}

/* ── Login split panel ────────────────────────────────────────────────── */
.ll-login-panel {
    background: var(--ll-navy);
    min-height: calc(100vh - 62px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: clamp(2rem, 5vw, 4rem);
    color: #fff;
}
.ll-login-panel .ll-eyebrow {
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--ll-fog);
}
.ll-login-panel .ll-headline {
    font-family: var(--ll-font-serif);
    font-size: clamp(1.9rem, 3vw + 1.2rem, 3.1rem);
    line-height: 1.15;
    color: #fff;
    margin: 0.75rem 0 1.1rem;
}
.ll-login-panel .ll-desc {
    font-size: clamp(1rem, 0.8vw + 0.85rem, 1.15rem);
    color: var(--ll-mist);
    line-height: 1.8;
    max-width: 34rem;
}
.ll-login-panel .ll-foot {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--ll-line);
    line-height: 1.7;
    margin-top: 3rem;
}
.ll-login-form-wrap {
    max-width: 440px;
    margin: 0 auto;
    padding: clamp(3rem, 9vh, 6rem) 1.5rem 2rem;
}
.ll-signin-title {
    font-family: var(--ll-font-serif);
    font-size: clamp(1.9rem, 2vw + 1.2rem, 2.4rem);
    color: var(--ll-navy);
}
.ll-signin-sub {
    font-size: 0.9rem;
    color: var(--ll-slate);
    margin-bottom: 1.75rem;
}

/* ── Cards / panels ────────────────────────────────────────────────────── */
.ll-card {
    background: #fff;
    border: 1px solid var(--ll-card-border);
    border-radius: var(--ll-radius);
    box-shadow: 0 1px 3px rgba(13, 33, 65, 0.06);
}

/* ── Tier badges ───────────────────────────────────────────────────────── */
.ll-badge {
    display: inline-block;
    padding: 0.3rem 0.85rem;
    border-radius: 999px;
    font-size: 0.8rem;
    font-weight: 600;
    color: #fff;
}
.ll-badge-novice     { background: var(--ll-novice); }
.ll-badge-developing { background: var(--ll-developing); }
.ll-badge-proficient { background: var(--ll-proficient); }

/* ── Buttons ───────────────────────────────────────────────────────────── */
.btn-ll-primary {
    background: var(--ll-navy);
    border-color: var(--ll-navy);
    color: #fff;
    font-weight: 600;
    min-height: 46px;
}
.btn-ll-primary:hover {
    background: var(--ll-navy-light);
    border-color: var(--ll-navy-light);
    color: #fff;
}

/* Small pill buttons for the Dashboard / Replay briefing nav row above
   each module's stage strip (module1_nav.php, module2_nav.php, module3_nav.php). */
.nav-pill-btn {
    display: inline-flex; align-items: center; gap: .4rem;
    padding: .35rem .9rem; border-radius: 999px;
    border: 1px solid #E2E8F0; background: #fff; color: #334155;
    font-size: .8rem; font-weight: 600; text-decoration: none;
    transition: background .15s ease, border-color .15s ease, color .15s ease;
}
.nav-pill-btn:hover, .nav-pill-btn:focus-visible {
    background: #F1F5F9; border-color: #94A3B8; color: var(--ll-navy);
}
.nav-pill-btn-ghost { background: transparent; color: #64748B; border-color: transparent; }
.nav-pill-btn-ghost:hover, .nav-pill-btn-ghost:focus-visible {
    background: #F8FAFC; border-color: #E2E8F0; color: #334155;
}

@media (max-width: 767.98px) {
    .ll-login-panel { min-height: auto; padding: 2rem 1.5rem; }
}

/* ── Concept-page callouts + step badges (shared across modules) ─────────── */
.concept-callout { border-radius: 12px; padding: 1rem 1.25rem; margin: 1.1rem 0; }
.concept-callout strong { display: block; margin-bottom: .4rem; color: var(--ll-navy); }
.concept-callout-blue   { background: #EBF6FC; border-left: 4px solid #1469A8; }
.concept-callout-amber  { background: #FFF4E8; border-left: 4px solid #C96800; }
.concept-callout-teal   { background: #ECF9F3; border-left: 4px solid #138A63; }
.concept-callout-purple { background: #F5F1FC; border-left: 4px solid #534AB7; }
.concept-step { display: flex; gap: .75rem; align-items: flex-start; margin-bottom: .9rem; }
.concept-step-num {
    flex: 0 0 auto; width: 1.9rem; height: 1.9rem; border-radius: 50%;
    display: grid; place-items: center; font-weight: 700; color: #fff; font-size: .9rem;
}
.concept-step-num.n1 { background: #1469A8; }
.concept-step-num.n2 { background: #C96800; }
.concept-step-num.n3 { background: #138A63; }
.concept-step-num.n4 { background: #534AB7; }
/* Shared numbered step-card component (originally Module 3's cf-step-card,
   promoted here so every module's step lists render identically). */
.cf-step-card{border:1px solid #E2E8F0;border-radius:16px;padding:1.25rem 1.4rem;margin-bottom:1.25rem;background:#fff}
.cf-step-head{display:flex;align-items:center;gap:.75rem;margin-bottom:.65rem}
.cf-step-head h2{margin:0}
.cf-step-num{flex:0 0 auto;width:2.15rem;height:2.15rem;border-radius:50%;display:grid;place-items:center;font-family:'DM Serif Display',serif;font-size:1.05rem;color:#fff}
.cf-step-num.n1{background:#1469A8}.cf-step-num.n2{background:#C96800}.cf-step-num.n3{background:#138A63}.cf-step-num.n4{background:#534AB7}
.cf-step-card.s1{background:#F8FCFE}.cf-step-card.s2{background:#FFFBF6}.cf-step-card.s3{background:#F7FDFB}.cf-step-card.s4{background:#FAF8FD}
.concept-mistake { display: flex; gap: .6rem; flex-wrap: wrap; margin-bottom: .6rem; }
.concept-mistake .wrong, .concept-mistake .right {
    flex: 1; min-width: 220px; padding: .6rem .75rem; border-radius: 8px; font-size: .85rem;
}
.concept-mistake .wrong { background: #FEF2F2; color: #991B1B; }
.concept-mistake .right { background: #F0FDF4; color: #166534; }
.concept-formula-box { background: #ECF9F3; border: 1px solid #C8EFDF; border-radius: 12px; padding: 1.1rem 1.25rem; margin: 1.1rem 0; }
.concept-formula-box .fw-semibold { color: #0F5C46; }

/* ── Equation chips + click-to-continue step reveal (Back-Door / Front-Door) ── */
.eq-step-title { font-weight: 700; font-size: .95rem; margin-bottom: .4rem; }
.eq-row { display: flex; align-items: center; gap: .55rem; flex-wrap: wrap; margin-bottom: .5rem; }
.eq-chip {
    display: inline-block; padding: .4rem .75rem; border-radius: 8px;
    font-family: 'Courier New', monospace; font-size: .8rem; font-weight: 700;
    border: 1.5px solid; line-height: 1.3;
}
.eq-chip.a { background: #F0FDF4; border-color: #16A34A; color: #15803D; }
.eq-chip.b { background: #FEF2F2; border-color: #DC2626; color: #B91C1C; }
.eq-op { font-weight: 700; color: #475569; font-size: 1.05rem; }
.eq-steps .eq-step { border-bottom: 1px dashed #E2E8F0; padding-bottom: 1rem; }
.eq-steps .eq-step:last-of-type { border-bottom: 0; padding-bottom: 0; }
/* Bootstrap's .d-flex carries display:flex !important, which otherwise beats
   the plain [hidden] user-agent rule and keeps "hidden" steps visible. */
.eq-steps .eq-step[hidden] { display: none !important; }
.eq-next-btn {
    border: 0; border-radius: 999px; padding: .5rem 1.15rem; color: #fff;
    font-weight: 700; font-size: .82rem; cursor: pointer; margin-top: .75rem;
}
.eq-next-btn.back:hover, .eq-next-btn.back { background: #1D9E75; }
.eq-next-btn.front:hover, .eq-next-btn.front { background: #534AB7; }
.eq-next-btn:hover { opacity: .88; }

/* Highlighted "step by step guidance" toggle - was plain muted text, easy to miss. */
.eq-guidance-toggle {
    display: inline-flex; align-items: center; gap: .5rem;
    padding: .55rem 1rem; border-radius: 10px; cursor: pointer;
    background: #EBF6FC; border: 1.5px solid #1469A8; color: #0D2141 !important;
    font-weight: 700; font-size: .88rem; list-style: none; margin-bottom: .75rem;
}
.eq-guidance-toggle::-webkit-details-marker { display: none; }
.eq-guidance-toggle:hover { background: #DCEFFA; }
.eq-guidance-toggle .eq-guidance-caret { transition: transform .15s ease; display: inline-block; }
details[open] > .eq-guidance-toggle .eq-guidance-caret { transform: rotate(90deg); }

/* ── Feasibility checks (Check 1 / Check 2): equation, given-vs-calculated, pass/fail ── */
.feas-check { background: #F7F8FA; border-radius: 12px; padding: 1rem 1.1rem; }
.feas-check-values { display: flex; gap: 1rem; flex-wrap: wrap; margin: .8rem 0; }
.feas-check-value {
    flex: 1; min-width: 180px; padding: .75rem 1rem; border-radius: 10px;
}
.feas-check-value.calc { background: #F0FDF4; border: 1.5px solid #16A34A; }
.feas-check-value.given { background: #FEF2F2; border: 1.5px solid #DC2626; }
.feas-check-value-label {
    font-size: .7rem; font-weight: 700; text-transform: uppercase;
    letter-spacing: .04em; margin-bottom: .3rem;
}
.feas-check-value.calc .feas-check-value-label { color: #15803D; }
.feas-check-value.given .feas-check-value-label { color: #B91C1C; }
.feas-check-editable {
    display: block; font-weight: 400; text-transform: none;
    font-size: .72rem; color: #475569; margin-top: .15rem;
}
.feas-check-value-num { font-size: 1.3rem; font-weight: 700; font-family: 'Courier New', monospace; }
.feas-check-value-sub { font-size: .72rem; color: #64748b; margin-top: .2rem; }
.feas-check-result {
    display: flex; align-items: center; gap: .4rem; flex-wrap: wrap;
    padding: .6rem .9rem; border-radius: 8px; font-weight: 700; font-size: .88rem;
    margin-bottom: .5rem;
}
.feas-check-result.pass { background: #ECFDF5; color: #15803D; }
.feas-check-result.fail { background: #FEF2F2; color: #B91C1C; }
.feas-check-hint summary { color: #1469A8; font-size: .85rem; cursor: pointer; font-weight: 600; }
.feas-check-hint-body { margin-top: .5rem; }

/* Per-step "click to continue" prompt in the Worked Example ledger. */
.ledger-reveal-row {
    cursor: pointer; display: inline-block; margin: .3rem 0 .6rem;
    padding: .4rem .7rem; border-radius: 8px;
    background: #EEF0FC; color: #3730A3; font-size: .8rem; font-weight: 700;
}
.ledger-reveal-row:hover { background: #E0E4FA; }