/**
 * LearningHub Practice System Styles
 * ==================================
 * Tab-based practice system for extended exercises
 *
 * Components:
 * - Tab navigation (Learn | Practice)
 * - Problem cards with difficulty badges
 * - Test cases display
 * - Hint reveal system
 * - Mini-project checkpoints
 * - Progress indicators
 */

/* ========================================
   TAB NAVIGATION
   ======================================== */

.learn-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    background: var(--bg-card);
    padding: 0.5rem;
    border-radius: 16px;
    width: fit-content;
}

.learn-tab {
    padding: 0.75rem 1.5rem;
    border-radius: 12px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.learn-tab:hover {
    color: var(--text-primary);
    background: var(--bg-secondary);
}

.learn-tab.active {
    background: var(--accent-green);
    color: #000;
}

.learn-tab.active:hover {
    background: var(--accent-green);
    color: #000;
}

/* Practice tab special styling when active */
.learn-tab[data-tab="practice"].active {
    background: linear-gradient(135deg, var(--accent-orange), var(--accent-red));
}

/* Tab content visibility */
.tab-content {
    display: none;
    animation: tabFadeIn 0.4s ease;
}

.tab-content.active {
    display: block;
}

@keyframes tabFadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ========================================
   PRACTICE HEADER
   ======================================== */

.practice-header {
    text-align: center;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(245, 158, 11, 0.15), rgba(239, 68, 68, 0.1));
    border-radius: 16px;
    border: 1px solid rgba(245, 158, 11, 0.3);
}

.practice-badge {
    display: inline-block;
    background: linear-gradient(135deg, var(--accent-orange), var(--accent-red));
    color: white;
    padding: 0.5rem 1.25rem;
    border-radius: 20px;
    font-weight: 700;
    font-size: 0.85rem;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.practice-header h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.practice-tagline {
    color: var(--text-secondary);
    font-style: italic;
    font-size: 0.95rem;
}

/* ========================================
   PROBLEM CARDS
   ======================================== */

.practice-problem {
    background: var(--bg-card);
    border-radius: 16px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border: 2px solid transparent;
    transition: all 0.3s ease;
}

.practice-problem:hover {
    border-color: var(--accent-orange);
    transform: translateY(-2px);
}

.practice-problem.completed {
    border-color: var(--accent-green);
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.1), var(--bg-card));
}

.practice-problem.completed::after {
    content: '✓ Rezolvat';
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--accent-green);
    color: #000;
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 700;
}

.practice-problem {
    position: relative;
}

/* Problem header */
.problem-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.problem-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.problem-number {
    color: var(--accent-orange);
    font-weight: 800;
    margin-right: 0.5rem;
}

/* Difficulty badges */
.difficulty-badge {
    padding: 0.35rem 0.85rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.difficulty-easy {
    background: rgba(16, 185, 129, 0.2);
    color: var(--accent-green);
    border: 1px solid var(--accent-green);
}

.difficulty-medium {
    background: rgba(245, 158, 11, 0.2);
    color: var(--accent-orange);
    border: 1px solid var(--accent-orange);
}

.difficulty-hard {
    background: rgba(239, 68, 68, 0.2);
    color: var(--accent-red);
    border: 1px solid var(--accent-red);
}

.difficulty-project {
    background: rgba(139, 92, 246, 0.2);
    color: var(--accent-purple);
    border: 1px solid var(--accent-purple);
}

/* Problem description */
.problem-desc {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

/* ========================================
   TEST CASES
   ======================================== */

.test-cases {
    margin: 1rem 0;
}

.test-cases-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 0.75rem;
}

.test-case {
    background: var(--bg-secondary);
    border-radius: 10px;
    padding: 1rem;
    margin-bottom: 0.75rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    border: 1px solid var(--border);
}

.test-case:last-child {
    margin-bottom: 0;
}

.test-io {
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 0.9rem;
}

.test-io-label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 0.25rem;
    display: block;
}

.test-io-value {
    color: var(--accent-cyan);
    background: var(--bg-primary);
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    display: block;
}

/* ========================================
   HINTS
   ======================================== */

.hint-wrapper {
    margin: 1rem 0;
}

.btn-hint {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1rem;
    background: transparent;
    border: 2px solid var(--accent-purple);
    border-radius: 10px;
    color: var(--accent-purple);
    font-family: 'Inter', sans-serif;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-hint:hover {
    background: rgba(139, 92, 246, 0.1);
}

.btn-hint.revealed {
    background: var(--accent-purple);
    color: white;
}

.hint-content {
    display: none;
    margin-top: 0.75rem;
    padding: 1rem;
    background: rgba(139, 92, 246, 0.1);
    border-left: 4px solid var(--accent-purple);
    border-radius: 0 10px 10px 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
    animation: hintReveal 0.3s ease;
}

.hint-content.revealed {
    display: block;
}

@keyframes hintReveal {
    from {
        opacity: 0;
        transform: translateX(-10px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* ========================================
   SOLVE BUTTON
   ======================================== */

.problem-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.25rem;
    flex-wrap: wrap;
}

.btn-solve {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan));
    border: none;
    border-radius: 12px;
    color: white;
    font-family: 'Inter', sans-serif;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-solve:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 25px rgba(16, 185, 129, 0.35);
}

.btn-solve.completed {
    background: var(--accent-green);
    pointer-events: none;
}

.btn-solve.completed::before {
    content: '✓ ';
}

/* ========================================
   MINI-PROJECTS
   ======================================== */

.practice-project {
    border-left: 4px solid var(--accent-purple);
}

.project-intro {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px dashed var(--border);
}

.checkpoints {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.checkpoint {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 10px;
    transition: all 0.2s ease;
}

.checkpoint:hover {
    background: var(--bg-primary);
}

.checkpoint.done {
    background: rgba(16, 185, 129, 0.1);
}

.checkpoint.done .checkpoint-text {
    text-decoration: line-through;
    color: var(--text-muted);
}

.checkpoint input[type="checkbox"] {
    width: 22px;
    height: 22px;
    margin-top: 2px;
    accent-color: var(--accent-green);
    cursor: pointer;
    flex-shrink: 0;
}

.checkpoint-text {
    color: var(--text-primary);
    font-size: 0.95rem;
    line-height: 1.5;
}

.checkpoint-step {
    display: inline-block;
    background: var(--accent-purple);
    color: white;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    text-align: center;
    line-height: 24px;
    font-size: 0.75rem;
    font-weight: 700;
    margin-right: 0.5rem;
    flex-shrink: 0;
}

/* ========================================
   PROGRESS INDICATOR
   ======================================== */

.practice-progress {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    background: var(--bg-card);
    border-radius: 12px;
    margin-bottom: 1.5rem;
}

.progress-bar {
    flex: 1;
    height: 10px;
    background: var(--bg-secondary);
    border-radius: 5px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
    border-radius: 5px;
    transition: width 0.5s ease;
}

.progress-text {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    min-width: 80px;
    text-align: right;
}

/* ========================================
   XP NOTIFICATION
   ======================================== */

.xp-notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 1rem 1.5rem;
    background: linear-gradient(135deg, var(--accent-orange), var(--accent-red));
    color: white;
    border-radius: 12px;
    font-weight: 700;
    font-size: 1.1rem;
    box-shadow: 0 10px 40px rgba(245, 158, 11, 0.4);
    z-index: 10000;
    animation: xpPopIn 0.5s ease, xpPopOut 0.5s ease 2.5s forwards;
}

@keyframes xpPopIn {
    from {
        opacity: 0;
        transform: translateY(-30px) scale(0.8);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

@keyframes xpPopOut {
    from {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
    to {
        opacity: 0;
        transform: translateY(-20px) scale(0.9);
    }
}

/* ========================================
   ALL COMPLETE CELEBRATION
   ======================================== */

.practice-complete {
    text-align: center;
    padding: 2rem;
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(6, 182, 212, 0.1));
    border: 2px solid var(--accent-green);
    border-radius: 16px;
    margin-top: 2rem;
    animation: celebratePulse 2s ease infinite;
}

@keyframes celebratePulse {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4);
    }
    50% {
        box-shadow: 0 0 0 15px rgba(16, 185, 129, 0);
    }
}

.practice-complete-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.practice-complete h3 {
    font-size: 1.5rem;
    color: var(--accent-green);
    margin-bottom: 0.5rem;
}

.practice-complete p {
    color: var(--text-secondary);
}

.practice-complete .xp-bonus {
    font-size: 1.3rem;
    color: var(--accent-orange);
    font-weight: 700;
    margin-top: 1rem;
}

/* ========================================
   MOBILE RESPONSIVENESS
   ======================================== */

@media (max-width: 768px) {
    .learn-tabs {
        width: 100%;
        justify-content: center;
    }

    .learn-tab {
        flex: 1;
        justify-content: center;
        padding: 0.65rem 1rem;
        font-size: 0.85rem;
    }

    .problem-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .test-case {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }

    .problem-actions {
        flex-direction: column;
    }

    .btn-solve,
    .btn-hint {
        width: 100%;
        justify-content: center;
    }

    .practice-progress {
        flex-direction: column;
        text-align: center;
    }

    .progress-text {
        min-width: auto;
        text-align: center;
    }

    .xp-notification {
        top: auto;
        bottom: 20px;
        left: 20px;
        right: 20px;
    }
}