/*
-----------------------------------------------------------
Copyright (c) 2026 Ahngunism. All rights reserved.
-----------------------------------------------------------
File           : style.css
Project        : 2304_MOON_KOREAN
Theme          : 2310_MOON_VIET 기반 · 다크/별/글라스 + 보라 액센트
-----------------------------------------------------------
*/

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Noto+Sans+KR:wght@400;500;700;800&display=swap');

/* ========== DESIGN TOKENS ========== */
:root {
    --bg-primary: #0f0a1a;
    --bg-secondary: #1a1127;
    --bg-card: rgba(26, 17, 39, 0.7);
    --bg-card-hover: rgba(36, 24, 54, 0.8);
    --glass-border: rgba(167, 139, 250, 0.2);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);

    --accent-primary: #a78bfa;
    --accent-secondary: #c4b5fd;
    --accent-glow: rgba(167, 139, 250, 0.3);
    --accent-gradient: linear-gradient(135deg, #a78bfa 0%, #7c3aed 100%);
    --accent-gradient-hover: linear-gradient(135deg, #7c3aed 0%, #a78bfa 100%);

    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;

    --correct-bg: rgba(52, 211, 153, 0.15);
    --correct-border: #34d399;
    --incorrect-bg: rgba(251, 113, 133, 0.15);
    --incorrect-border: #fb7185;
    --neutral-bg: rgba(148, 163, 184, 0.1);
    --neutral-border: rgba(148, 163, 184, 0.3);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========== RESET & BASE ========== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 24px 16px;
    overflow-x: hidden;
    position: relative;
}

/* ========== ANIMATED BACKGROUND ========== */
body::before {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background:
        radial-gradient(ellipse at 20% 50%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(167, 139, 250, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 80%, rgba(236, 72, 153, 0.05) 0%, transparent 50%);
    animation: bgShift 20s ease-in-out infinite alternate;
    z-index: -1;
}

@keyframes bgShift {
    0% { transform: translate(0, 0) rotate(0deg); }
    100% { transform: translate(-5%, -5%) rotate(3deg); }
}

/* ========== STARS ========== */
.stars {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
}

.star {
    position: absolute;
    width: 2px;
    height: 2px;
    background: white;
    border-radius: 50%;
    animation: twinkle var(--duration) ease-in-out infinite alternate;
    opacity: 0;
}

@keyframes twinkle {
    0% { opacity: 0; transform: scale(0.5); }
    100% { opacity: var(--max-opacity); transform: scale(1); }
}

/* ========== HERO ========== */
.hero {
    text-align: center;
    margin-bottom: 8px;
}

.hero-moon {
    font-size: 4rem;
    margin-bottom: 8px;
    animation: moonFloat 4s ease-in-out infinite;
    filter: drop-shadow(0 0 20px rgba(251, 191, 36, 0.3));
}

@keyframes moonFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.hero h1 {
    font-family: 'Noto Sans KR', 'Outfit', sans-serif;
    font-size: 2.2rem;
    font-weight: 800;
    background: linear-gradient(135deg, #f1f5f9, #a78bfa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.2;
    margin-bottom: 8px;
}

.hero p {
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 400;
}

/* ========== FEATURE CARDS (HOME) ========== */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    width: 100%;
    max-width: 640px;
    margin-top: 16px;
}

.feature-card {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: 24px 20px;
    transition: border-color var(--transition-smooth);
    display: flex;
    flex-direction: column;
}

.feature-card:hover {
    border-color: rgba(167, 139, 250, 0.4);
}

.feature-icon {
    font-size: 2.2rem;
    margin-bottom: 10px;
}

.feature-title {
    font-family: 'Noto Sans KR', 'Outfit', sans-serif;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.feature-desc {
    font-size: 0.82rem;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 16px;
    flex: 1;
}

.card-actions {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.btn-link {
    display: block;
    padding: 9px 14px;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 0.88rem;
    font-weight: 600;
    text-align: center;
    transition: all var(--transition-fast);
    background: var(--neutral-bg);
    border: 1.5px solid var(--neutral-border);
    color: var(--text-secondary);
}

.btn-link:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    background: rgba(167, 139, 250, 0.08);
    transform: translateY(-1px);
}

.btn-link.primary {
    background: var(--accent-gradient);
    border-color: transparent;
    color: white;
    box-shadow: 0 4px 15px var(--accent-glow);
}

.btn-link.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--accent-glow);
    color: white;
}

/* ========== TITLE BAR (INNER PAGES) ========== */
.title-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: 680px;
    padding: 4px 0 12px;
}

.title-bar__home {
    display: flex;
    align-items: center;
    gap: 6px;
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 0.88rem;
    font-weight: 600;
    transition: color var(--transition-fast);
}

.title-bar__home:hover {
    color: var(--accent-primary);
}

.title-bar__cat {
    font-size: 0.82rem;
    font-weight: 700;
    color: var(--accent-primary);
    background: rgba(167, 139, 250, 0.12);
    border: 1px solid rgba(167, 139, 250, 0.3);
    padding: 4px 14px;
    border-radius: 20px;
    white-space: nowrap;
}

/* ========== PAGE CONTAINER ========== */
.page-container {
    width: 100%;
    max-width: 680px;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
}

.page-header {
    text-align: center;
    margin-bottom: 20px;
}

.page-title {
    font-family: 'Noto Sans KR', 'Outfit', sans-serif;
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.page-sub {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ========== SUBNAV ========== */
.subnav {
    display: flex;
    gap: 8px;
    width: 100%;
    margin-bottom: 20px;
}

.subnav-btn {
    flex: 1;
    padding: 10px 12px;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 0.88rem;
    font-weight: 600;
    text-align: center;
    background: var(--neutral-bg);
    border: 1.5px solid var(--neutral-border);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.subnav-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.subnav-btn.active {
    background: var(--accent-gradient);
    border-color: transparent;
    color: white;
    pointer-events: none;
}

/* ========== SETTINGS FORM ========== */
.settings-form {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: 24px;
    box-shadow: var(--glass-shadow);
    margin-bottom: 16px;
}

.settings-form fieldset {
    border: none;
    padding: 0;
    margin-bottom: 20px;
}

.settings-form fieldset:last-of-type {
    margin-bottom: 0;
}

.settings-form legend {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 10px;
}

.scroll-group {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
}

.scroll-group input[type="radio"] {
    display: none;
}

.scroll-group label {
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    background: var(--neutral-bg);
    border: 1.5px solid var(--neutral-border);
    color: var(--text-secondary);
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 0.88rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.scroll-group label:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.scroll-group input[type="radio"]:checked + label {
    background: var(--accent-gradient);
    border-color: transparent;
    color: white;
    font-weight: 600;
    box-shadow: 0 3px 10px var(--accent-glow);
}

.start-button {
    width: 100%;
    padding: 14px;
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 1.05rem;
    font-weight: 700;
    color: white;
    background: var(--accent-gradient);
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: 0 4px 20px var(--accent-glow);
    margin-top: 20px;
}

.start-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 28px var(--accent-glow);
}

/* ========== WORDBOOK ========== */
.layout-controls {
    display: flex;
    gap: 8px;
    margin-bottom: 12px;
}

.layout-btn {
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    background: var(--neutral-bg);
    border: 1.5px solid var(--neutral-border);
    color: var(--text-secondary);
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.layout-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.layout-btn.active {
    background: var(--accent-gradient);
    border-color: transparent;
    color: white;
}

.wordbook-list {
    display: grid;
    gap: 6px;
    width: 100%;
}

.wordbook-list.cols-1 { grid-template-columns: 1fr; }
.wordbook-list.cols-3 { grid-template-columns: repeat(3, 1fr); }
.wordbook-list.cols-5 { grid-template-columns: repeat(5, 1fr); }

.wb-row {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    background: var(--bg-card);
    border: 1.5px solid var(--glass-border);
    cursor: pointer;
    transition: all var(--transition-fast);
    min-height: 44px;
}

.wb-row:hover {
    border-color: var(--accent-primary);
    background: var(--bg-card-hover);
}

.cols-3 .wb-row,
.cols-5 .wb-row {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 4px;
    padding: 10px 8px;
}

.wb-idx {
    font-size: 0.75rem;
    color: var(--text-muted);
    min-width: 24px;
}

.cols-3 .wb-idx,
.cols-5 .wb-idx {
    font-size: 0.7rem;
    min-width: auto;
}

.wb-en {
    font-family: 'Noto Sans KR', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-primary);
    flex: 1;
    word-break: keep-all;
}

.cols-3 .wb-en,
.cols-5 .wb-en {
    font-size: 0.92rem;
    flex: none;
}

.wb-kr {
    font-family: 'Outfit', sans-serif;
    font-size: 0.9rem;
    color: var(--accent-primary);
    font-weight: 500;
}

.cols-3 .wb-kr,
.cols-5 .wb-kr {
    font-size: 0.8rem;
}

.wb-hidden {
    visibility: hidden;
    height: 0;
    overflow: hidden;
    padding: 0;
    margin: 0;
}

.cols-3 .wb-hidden,
.cols-5 .wb-hidden {
    display: none;
}

/* ========== FLASHCARD ========== */
.fc-wrapper {
    perspective: 1000px;
    width: 100%;
    max-width: 480px;
    margin: 0 auto 16px;
}

.fc-card {
    position: relative;
    width: 100%;
    padding-top: 60%;
    transform-style: preserve-3d;
    transition: transform 0.45s ease;
    cursor: pointer;
}

.fc-card.flipped {
    transform: rotateY(180deg);
}

.fc-front,
.fc-back {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 8px;
    border-radius: var(--radius-xl);
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1.5px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    padding: 20px;
    text-align: center;
}

.fc-back {
    transform: rotateY(180deg);
    border-color: rgba(167, 139, 250, 0.3);
}

.fc-counter {
    position: absolute;
    top: 14px;
    right: 18px;
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-muted);
}

.fc-word {
    font-family: 'Noto Sans KR', sans-serif;
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
    text-shadow: 0 0 40px var(--accent-glow);
    word-break: keep-all;
    line-height: 1.3;
}

.fc-meaning {
    font-family: 'Outfit', sans-serif;
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--accent-primary);
    word-break: break-word;
    line-height: 1.3;
}

.fc-tap-hint {
    font-size: 0.78rem;
    color: var(--text-muted);
    margin-top: 4px;
}

.fc-progress-wrap {
    width: 100%;
    max-width: 480px;
    margin: 0 auto 12px;
}

.fc-progress-bar {
    width: 100%;
    height: 5px;
    background: rgba(148, 163, 184, 0.15);
    border-radius: 3px;
    overflow: hidden;
}

.fc-progress-inner {
    height: 100%;
    background: var(--accent-gradient);
    border-radius: 3px;
    transition: width 0.35s ease;
}

.fc-nav {
    display: flex;
    gap: 8px;
    width: 100%;
    max-width: 480px;
    margin: 0 auto 16px;
}

.fc-nav-btn {
    flex: 1;
    padding: 10px 12px;
    border-radius: var(--radius-md);
    background: var(--neutral-bg);
    border: 1.5px solid var(--neutral-border);
    color: var(--text-secondary);
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 0.88rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.fc-nav-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-1px);
}

.fc-control-bar {
    display: flex;
    align-items: stretch;
    justify-content: space-between;
    gap: 8px;
    width: 100%;
    max-width: 480px;
    margin: 0 auto;
    padding: 6px 10px;
    background: rgba(255, 255, 255, 0.03);
    border-radius: var(--radius-sm);
    border: 1px solid var(--glass-border);
}

.fc-play-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 8px;
    background: transparent;
    border: none;
    cursor: pointer;
    color: var(--text-primary);
    transition: all var(--transition-fast);
    border-radius: var(--radius-sm);
}

.fc-play-btn:hover {
    background: rgba(167, 139, 250, 0.12);
}

.fc-divider {
    width: 1px;
    background: var(--glass-border);
    margin: 4px 0;
}

.fc-speed-group {
    display: flex;
    gap: 4px;
    align-items: center;
}

.speed-btn {
    padding: 5px 10px;
    border-radius: var(--radius-sm);
    background: transparent;
    border: 1.5px solid var(--neutral-border);
    color: var(--text-muted);
    font-family: 'Outfit', sans-serif;
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.speed-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.speed-btn.active {
    background: var(--accent-gradient);
    border-color: transparent;
    color: white;
}

/* ========== QUIZ ========== */
.quiz-container {
    width: 100%;
    max-width: 640px;
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: 32px;
    box-shadow: var(--glass-shadow);
    text-align: center;
    transition: border-color var(--transition-smooth);
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: rgba(148, 163, 184, 0.15);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-bar-inner {
    height: 100%;
    width: 0%;
    background: var(--accent-gradient);
    border-radius: 3px;
    transition: width 0.4s ease;
}

.progress-text {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: 24px;
}

.question-display {
    font-family: 'Noto Sans KR', sans-serif;
    font-size: clamp(2.4rem, 8vw, 3.6rem);
    font-weight: 800;
    color: var(--text-primary);
    min-height: 170px;
    display: flex;
    justify-content: center;
    align-items: center;
    text-shadow: 0 0 60px var(--accent-glow);
    opacity: 1;
    transition: opacity 0.3s ease-in-out;
    cursor: pointer;
    text-align: center;
    word-break: keep-all;
    line-height: 1.2;
    padding: 8px;
}

.question-display.fade-out {
    opacity: 0;
}

.question-display.show-answer {
    font-family: 'Outfit', sans-serif;
    font-size: clamp(1.8rem, 6vw, 2.8rem);
    color: var(--accent-primary);
}

.quiz-hint {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 16px;
    letter-spacing: 0.02em;
}

.answer-input {
    width: 100%;
    max-width: 360px;
    padding: 14px 20px;
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 1.2rem;
    font-weight: 500;
    text-align: center;
    background: rgba(30, 41, 59, 0.6);
    border: 2px solid var(--neutral-border);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    outline: none;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.answer-input:focus {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.answer-input::placeholder {
    color: var(--text-muted);
}

.button-container {
    display: flex;
    gap: 12px;
    margin-top: 24px;
}

.quiz-nav-button {
    flex: 1;
    padding: 12px 20px;
    border-radius: var(--radius-md);
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 1.5px solid transparent;
    text-align: center;
    text-decoration: none;
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 15px var(--accent-glow);
}

.quiz-nav-button:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px var(--accent-glow);
}

.quiz-nav-button.secondary {
    background: transparent;
    border-color: var(--neutral-border);
    color: var(--text-secondary);
    box-shadow: none;
}

.quiz-nav-button.secondary:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    background: rgba(167, 139, 250, 0.08);
}

.feedback-correct {
    animation: flash-correct 0.5s;
}
.feedback-incorrect {
    animation: flash-incorrect 0.5s;
}
@keyframes flash-correct {
    50% { background-color: var(--correct-bg); border-color: var(--correct-border); }
}
@keyframes flash-incorrect {
    50% { background-color: var(--incorrect-bg); border-color: var(--incorrect-border); }
}

/* ========== RESULT ========== */
.result-container {
    width: 100%;
    max-width: 800px;
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: 32px;
    box-shadow: var(--glass-shadow);
    text-align: center;
}

.result-container h1 {
    font-family: 'Noto Sans KR', 'Outfit', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 4px;
    background: none;
    -webkit-text-fill-color: var(--text-primary);
}

.score {
    font-family: 'Outfit', sans-serif;
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, #34d399, #a78bfa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin: 16px 0;
}

.legend {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 28px;
    flex-wrap: wrap;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.legend-color {
    width: 12px;
    height: 12px;
    border-radius: 3px;
}

.chart-container {
    margin-top: 20px;
}

.chart-container h3 {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent-primary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    text-align: center;
    padding-bottom: 8px;
    margin-bottom: 12px;
    border-bottom: 1px solid var(--glass-border);
}

/* ========== WORD RESULT GRID ========== */
.word-result-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: 8px;
    margin-bottom: 24px;
}

.word-cell {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 52px;
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    font-family: 'Noto Sans KR', sans-serif;
    font-size: 0.95rem;
    font-weight: 700;
    background: var(--neutral-bg);
    border: 1.5px solid var(--neutral-border);
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-fast);
    user-select: none;
    text-align: center;
    word-break: keep-all;
    line-height: 1.3;
}

.word-cell:hover {
    background: rgba(167, 139, 250, 0.15);
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--accent-glow);
}

.word-cell.correct {
    background: var(--correct-bg);
    border-color: var(--correct-border);
}

.word-cell.incorrect {
    background: var(--incorrect-bg);
    border-color: var(--incorrect-border);
}

.word-cell.show-kr {
    font-family: 'Outfit', sans-serif;
    font-size: 0.85rem;
    color: var(--accent-primary);
}

.word-cell.fade-out {
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
}

.retry-button {
    display: inline-block;
    width: 100%;
    padding: 16px;
    font-family: 'Outfit', 'Noto Sans KR', sans-serif;
    font-size: 1.15rem;
    font-weight: 700;
    color: white;
    background: var(--accent-gradient);
    border: none;
    border-radius: var(--radius-lg);
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: 0 4px 20px var(--accent-glow);
    margin-top: 32px;
    position: relative;
    overflow: hidden;
}

.retry-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(167, 139, 250, 0.4);
}

/* ========== AD CONTAINERS ========== */
.ad-grid {
    display: grid;
    grid-template-columns: repeat(2, 320px);
    gap: 12px;
    justify-content: center;
    margin-top: 20px;
}

.ad-mobile-container-320-50-center {
    display: block;
    width: 320px;
    min-height: 50px;
}

.ad-mobile-container-320-100-center {
    display: block;
    width: 320px;
    min-height: 100px;
}

@media (max-width: 680px) {
    .ad-grid {
        grid-template-columns: 320px;
    }
}

/* ========== RESPONSIVE ========== */
@media (max-width: 480px) {
    .hero h1 { font-size: 1.7rem; }
    .hero-moon { font-size: 3rem; }
    .quiz-container { padding: 24px 20px; }
    .result-container { padding: 24px 20px; }
    .question-display { min-height: 140px; }
    .score { font-size: 2.2rem; }
    .feature-grid { grid-template-columns: 1fr; }
    .fc-word { font-size: 1.6rem; }
    .fc-meaning { font-size: 1.3rem; }
    .wordbook-list.cols-5 { grid-template-columns: repeat(3, 1fr); }
}