/* ── Fonts (self-hosted) ────────────────────────── */
/* latin-ext */
@font-face {
  font-family: 'Bebas Neue';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('fonts/BebasNeue-400-latin-ext.woff2') format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Bebas Neue';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('fonts/BebasNeue-400-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
/* latin-ext */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 700;
  font-display: swap;
  src: url('fonts/Inter-400-latin-ext.woff2') format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400 700;
  font-display: swap;
  src: url('fonts/Inter-400-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* ── Variables ───────────────────────────────────── */
:root {
    --btc-orange:  #F7931A;
    --btc-amber:   #FFB700;
    --btc-red:     #FF5A1A;
    --fiat-green:  #3EA86A;
    --dark-bg:     #080401;
    --darker-bg:   #040200;
    --card-bg:     #0f0700;
    --card-border: #2a1200;
    --light-text:  #fff8f0;
    --gray-text:   #9a7d60;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ── Animations ──────────────────────────────────── */
@keyframes orange-flicker {
    0%, 18%, 22%, 25%, 53%, 57%, 100% {
        text-shadow: 0 0 8px var(--btc-orange), 0 0 22px var(--btc-orange), 0 0 50px var(--btc-orange);
        opacity: 1;
    }
    19%, 24%, 54%, 56% {
        text-shadow: none;
        opacity: 0.85;
    }
}

@keyframes orange-pulse {
    0%, 100% { box-shadow: 0 0 20px rgba(247,147,26,0.10), 0 0 40px rgba(247,147,26,0.05); }
    50%       { box-shadow: 0 0 38px rgba(247,147,26,0.20), 0 0 75px rgba(247,147,26,0.09); }
}

/* ── Base ────────────────────────────────────────── */
body {
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--light-text);
    background: var(--dark-bg);
    background-image:
        radial-gradient(ellipse at 15% 50%, rgba(247,147,26,0.06) 0%, transparent 55%),
        radial-gradient(ellipse at 85% 15%, rgba(255,90,26,0.04)  0%, transparent 50%),
        radial-gradient(ellipse at 50% 90%, rgba(255,183,0,0.03)  0%, transparent 50%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a { color: var(--btc-amber); text-decoration: none; transition: color 0.2s, text-shadow 0.2s; }
a:hover { color: var(--btc-orange); text-shadow: 0 0 8px var(--btc-orange); }

.container {
    width: 90%;
    max-width: 700px;
    margin: 0 auto;
    padding: 0 15px;
}

/* ── Header ─────────────────────────────────────── */
header {
    background: var(--darker-bg);
    padding: 18px 0;
    border-bottom: 1px solid rgba(247,147,26,0.25);
    box-shadow: 0 2px 20px rgba(247,147,26,0.10);
}
header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
}
.site-title {
    font-family: 'Bebas Neue', 'Impact', sans-serif;
    font-size: 1.9rem;
    font-weight: 400;
    letter-spacing: 0.08em;
    color: var(--light-text);
}
.site-title .btc-word {
    color: var(--btc-orange);
    text-shadow: 0 0 8px var(--btc-orange), 0 0 25px var(--btc-orange);
    animation: orange-flicker 9s infinite;
}
.header-tagline {
    font-size: 0.72rem;
    color: var(--gray-text);
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

/* ── Language switcher ──────────────────────────── */
.lang-switcher {
    display: flex;
    gap: 6px;
}
.lang-btn {
    background: transparent;
    border: 1px solid rgba(247,147,26,0.3);
    color: var(--gray-text);
    border-radius: 6px;
    padding: 5px 11px;
    font-size: 0.78rem;
    font-family: 'Inter', sans-serif;
    font-weight: 700;
    letter-spacing: 0.06em;
    cursor: pointer;
    transition: all 0.2s;
}
.lang-btn:hover,
.lang-btn.active {
    background: rgba(247,147,26,0.12);
    border-color: var(--btc-orange);
    color: var(--btc-orange);
    text-shadow: 0 0 8px var(--btc-orange);
}

/* ── Main ───────────────────────────────────────── */
main { flex: 1; }

/* ── Intro ───────────────────────────────────────── */
.intro {
    padding: 52px 0 32px;
    text-align: center;
}
.intro h1 {
    font-family: 'Bebas Neue', 'Impact', sans-serif;
    font-size: 3.6rem;
    font-weight: 400;
    letter-spacing: 0.06em;
    margin-bottom: 16px;
    line-height: 1.05;
}
.intro h1 .btc-word {
    color: var(--btc-orange);
    text-shadow: 0 0 14px var(--btc-orange), 0 0 45px rgba(247,147,26,0.5);
}
.intro h1 .fiat-word {
    color: var(--gray-text);
}
.intro p {
    color: var(--gray-text);
    font-size: 1rem;
    max-width: 500px;
    margin: 0 auto;
}

/* ── Quiz section ────────────────────────────────── */
.quiz-section { padding: 8px 0 48px; }

.quiz-progress-label {
    font-size: 0.75rem;
    color: var(--gray-text);
    margin-bottom: 8px;
    text-align: center;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}
.quiz-bar-track {
    height: 3px;
    background: rgba(255,255,255,0.06);
    border-radius: 2px;
    margin-bottom: 28px;
    overflow: hidden;
}
.quiz-bar-fill {
    height: 100%;
    background: var(--btc-orange);
    box-shadow: 0 0 8px var(--btc-orange), 0 0 18px rgba(247,147,26,0.6);
    transition: width 0.4s ease;
    width: 0%;
}

.quiz-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 44px 32px 38px;
    text-align: center;
    margin-bottom: 24px;
    box-shadow: 0 0 40px rgba(247,147,26,0.07), inset 0 0 40px rgba(0,0,0,0.4);
    animation: orange-pulse 4s ease-in-out infinite;
    min-height: 160px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 12px;
}
.quiz-name {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--light-text);
    line-height: 1.45;
    max-width: 540px;
}
.quiz-feedback {
    min-height: 26px;
    font-size: 0.92rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}
.quiz-feedback--correct {
    color: var(--btc-amber);
    text-shadow: 0 0 10px var(--btc-amber);
}
.quiz-feedback--wrong {
    color: var(--btc-red);
    text-shadow: 0 0 10px var(--btc-red);
}

.quiz-answers {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 20px;
}
.btn-answer {
    padding: 20px 12px;
    border: 2px solid transparent;
    border-radius: 10px;
    font-family: 'Bebas Neue', 'Impact', sans-serif;
    font-size: 1.4rem;
    letter-spacing: 0.12em;
    font-weight: 400;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    transition: background 0.2s, box-shadow 0.2s, transform 0.1s;
}
.btn-answer:active { transform: scale(0.96); }

.btn-answer--bitcoin {
    background: rgba(247,147,26,0.07);
    border-color: var(--btc-orange);
    color: var(--btc-orange);
    text-shadow: 0 0 10px var(--btc-orange);
    box-shadow: 0 0 12px rgba(247,147,26,0.2), inset 0 0 12px rgba(247,147,26,0.04);
}
.btn-answer--bitcoin:hover {
    background: rgba(247,147,26,0.16);
    box-shadow: 0 0 28px rgba(247,147,26,0.55), inset 0 0 18px rgba(247,147,26,0.08);
}
.btn-answer--fiat {
    background: rgba(62,168,106,0.06);
    border-color: var(--fiat-green);
    color: var(--fiat-green);
    text-shadow: 0 0 10px var(--fiat-green);
    box-shadow: 0 0 12px rgba(62,168,106,0.18), inset 0 0 12px rgba(62,168,106,0.04);
}
.btn-answer--fiat:hover {
    background: rgba(62,168,106,0.14);
    box-shadow: 0 0 28px rgba(62,168,106,0.45), inset 0 0 18px rgba(62,168,106,0.08);
}
.btn-answer:disabled {
    opacity: 0.35;
    cursor: default;
    box-shadow: none;
    text-shadow: none;
}

/* ── Results ────────────────────────────────────── */
#quiz-results { text-align: center; }
.result-score {
    font-family: 'Bebas Neue', 'Impact', sans-serif;
    font-size: 5.5rem;
    font-weight: 400;
    letter-spacing: 0.05em;
    color: var(--btc-orange);
    text-shadow: 0 0 20px var(--btc-orange), 0 0 55px rgba(247,147,26,0.4);
    line-height: 1;
    margin-bottom: 6px;
}
.result-label {
    font-size: 0.8rem;
    color: var(--gray-text);
    margin-bottom: 12px;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}
.result-verdict {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 32px;
    color: var(--btc-amber);
    text-shadow: 0 0 10px var(--btc-amber);
}

.review-list {
    list-style: none;
    padding: 0;
    text-align: left;
    margin-bottom: 28px;
}
.review-list li {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 10px 14px;
    margin-bottom: 6px;
    border-radius: 8px;
    font-size: 0.88rem;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
}
.review-list li.r-correct { border-left: 3px solid var(--btc-amber); }
.review-list li.r-wrong   { border-left: 3px solid var(--btc-red); }
.review-name { flex: 1; font-weight: 500; color: var(--light-text); line-height: 1.4; }
.review-badge {
    font-size: 0.67rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: 2px 8px;
    border-radius: 99px;
    letter-spacing: 0.05em;
    white-space: nowrap;
    align-self: center;
}
.review-badge--bitcoin {
    background: rgba(247,147,26,0.12);
    color: var(--btc-orange);
    border: 1px solid var(--btc-orange);
}
.review-badge--fiat {
    background: rgba(62,168,106,0.10);
    color: var(--fiat-green);
    border: 1px solid var(--fiat-green);
}
.review-icon { font-size: 1rem; align-self: center; }
.review-icon--correct { color: var(--btc-amber); text-shadow: 0 0 8px var(--btc-amber); }
.review-icon--wrong   { color: var(--btc-red);   text-shadow: 0 0 8px var(--btc-red); }

.btn-restart {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    background: transparent;
    color: var(--btc-orange);
    border: 2px solid var(--btc-orange);
    border-radius: 8px;
    font-family: 'Bebas Neue', 'Impact', sans-serif;
    font-size: 1.25rem;
    letter-spacing: 0.1em;
    cursor: pointer;
    text-shadow: 0 0 10px var(--btc-orange);
    box-shadow: 0 0 14px rgba(247,147,26,0.25);
    transition: background 0.2s, box-shadow 0.2s;
}
.btn-restart:hover {
    background: rgba(247,147,26,0.12);
    box-shadow: 0 0 28px rgba(247,147,26,0.5);
}

/* ── About / FAQ ─────────────────────────────────── */
.about-section {
    padding: 40px 0;
    border-top: 1px solid rgba(247,147,26,0.15);
}
.about-section h2 {
    font-family: 'Bebas Neue', 'Impact', sans-serif;
    font-size: 1.9rem;
    font-weight: 400;
    letter-spacing: 0.08em;
    margin-bottom: 20px;
    color: var(--btc-orange);
    text-shadow: 0 0 12px var(--btc-orange);
}
details {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 14px 18px;
    margin-bottom: 10px;
}
summary {
    font-weight: 600;
    cursor: pointer;
    list-style: none;
    user-select: none;
    color: var(--light-text);
}
summary::after { content: ' ▾'; color: var(--btc-orange); font-size: 0.85rem; }
details[open] summary::after { content: ' ▴'; }
.faq-body {
    margin-top: 10px;
    font-size: 0.92rem;
    color: var(--gray-text);
    line-height: 1.65;
}

/* ── Footer ─────────────────────────────────────── */
footer {
    background: var(--darker-bg);
    padding: 24px 0;
    text-align: center;
    font-size: 0.82rem;
    color: var(--gray-text);
    border-top: 1px solid rgba(247,147,26,0.15);
}
footer a { color: var(--gray-text); }
footer a:hover { color: var(--btc-orange); text-shadow: 0 0 8px var(--btc-orange); }

/* ── Responsive ─────────────────────────────────── */
@media (max-width: 480px) {
    .intro h1 { font-size: 2.5rem; }
    .quiz-name { font-size: 1.05rem; }
    .quiz-card { padding: 32px 18px 28px; }
    .quiz-answers { grid-template-columns: 1fr; }
    .result-score { font-size: 4.5rem; }
}