/* ========================================
   STUDY GUIDE PANEL
======================================== */

.study-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 100%);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-family: var(--font-main);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px var(--accent-glow);
}

.study-btn svg {
    width: 18px;
    height: 18px;
}

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

.study-panel {
    display: none;
    animation: fadeIn 0.4s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.study-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 2rem;
    background: linear-gradient(135deg, rgba(167, 139, 250, 0.15) 0%, rgba(244, 114, 182, 0.15) 100%);
    border: 1px solid rgba(167, 139, 250, 0.3);
    border-radius: var(--radius-lg);
    margin-bottom: 2rem;
}

.study-header-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.study-header-left .header-icon {
    width: 40px;
    height: 40px;
    color: var(--accent);
}

.study-header-left h2 {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.25rem;
}

.study-header-left p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.study-exit-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-main);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.study-exit-btn svg {
    width: 18px;
    height: 18px;
}

.study-exit-btn:hover {
    background: var(--accent-red);
    border-color: var(--accent-red);
    color: white;
}

.study-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.study-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: var(--text-primary);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.study-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.study-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px var(--accent-glow);
    border-color: var(--accent);
}

.study-card:hover::before {
    transform: scaleX(1);
}

.study-card-icon {
    width: 48px;
    height: 48px;
    flex-shrink: 0;
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
}

.study-card-icon svg {
    width: 32px;
    height: 32px;
}

.study-card.vocabulary .study-card-icon {
    color: var(--accent-green);
}

.study-card-content {
    flex: 1;
}

.study-card-content h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.study-card-content p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.study-card-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    padding: 0.25rem 0.75rem;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    font-size: 0.7rem;
    font-weight: 700;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.study-card.vocabulary {
    border-color: rgba(34, 197, 94, 0.3);
}

.study-card.vocabulary::before {
    background: linear-gradient(90deg, var(--accent-green), var(--accent-teal));
}

.study-card.vocabulary:hover {
    border-color: var(--accent-green);
    box-shadow: 0 8px 30px rgba(34, 197, 94, 0.2);
}

.study-card.vocabulary .study-card-badge {
    background: linear-gradient(135deg, var(--accent-green), var(--accent-teal));
}

.study-tips {
    padding: 1.5rem 2rem;
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.1) 0%, rgba(20, 184, 166, 0.1) 100%);
    border: 1px solid rgba(34, 197, 94, 0.3);
    border-radius: var(--radius-lg);
}

.study-tips h3 {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent-green);
    margin-bottom: 1rem;
}

.study-tips h3 svg {
    width: 22px;
    height: 22px;
}

.study-tips ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.study-tips li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.study-tips li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent-green);
    font-weight: bold;
}

.study-tips li:last-child {
    margin-bottom: 0;
}