/* ================================
   LESSON PAGE - ULTRA MODERN
================================ */

.lesson-wrapper {
    min-height: 70vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ================================
   MAIN CARD
================================ */

.lesson-card {
    position: relative;
    width: 100%;
    max-width: 650px;
    padding: 2.2rem;
    border-radius: var(--radius-lg);

    background: var(--bg-glass);
    backdrop-filter: var(--glass-blur);

    border: var(--glass-border);

    box-shadow: var(--shadow-lg);

    overflow: hidden;

    transition: 0.4s ease;
}

/* animated gradient border */
.lesson-card::before {
    content: "";
    position: absolute;
    inset: -1px;
    border-radius: inherit;
    padding: 1px;

    background: linear-gradient(
        130deg,
        var(--primary-color),
        var(--secondary-color),
        var(--accent-color),
        var(--primary-color)
    );

    background-size: 300% 300%;

    animation: borderMove 6s linear infinite;

    -webkit-mask:
        linear-gradient(#000 0 0) content-box,
        linear-gradient(#000 0 0);

    -webkit-mask-composite: xor;
    mask-composite: exclude;

    pointer-events: none;
}

@keyframes borderMove {
    0% { background-position: 0% }
    100% { background-position: 300% }
}

.lesson-card:hover {
    transform: translateY(-6px);
}

/* ================================
   TITLE
================================ */

.lesson-title {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 8px;
}

.lesson-unit {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 25px;
}

/* ================================
   BUTTON GRID
================================ */

.lesson-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

/* ================================
   BUTTON BASE
================================ */

.lesson-btn {
    position: relative;

    padding: 1.2rem;
    border-radius: var(--radius-md);

    font-weight: 700;
    font-size: 1rem;

    border: none;

    cursor: pointer;

    overflow: hidden;

    transition: 0.3s;

    box-shadow: var(--shadow-md);

    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;

    text-decoration: none;
}

/* shine effect */
.lesson-btn::after {
    content: "";
    position: absolute;
    top: 0;
    left: -120%;
    width: 100%;
    height: 100%;

    background: linear-gradient(
        120deg,
        transparent,
        rgba(255,255,255,0.5),
        transparent
    );

    transition: 0.5s;
}

.lesson-btn:hover::after {
    left: 120%;
}

.lesson-btn:active {
    transform: scale(0.97);
}

/* ================================
   VIDEO BUTTON
================================ */

.btn-video {

    background: linear-gradient(
        135deg,
        var(--primary-color),
        var(--secondary-color)
    );

    color: white;
}

.btn-video:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 40px rgba(67,97,238,0.35);
}

/* ================================
   SOLUTION BUTTON
================================ */

.btn-solution {

    background: linear-gradient(
        135deg,
        var(--accent-color),
        var(--warning-color)
    );

    color: white;
}

.btn-solution:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 40px rgba(247,37,133,0.35);
}

/* ================================
   MOBILE OPTIMIZATION
================================ */

@media (max-width: 768px) {

    .lesson-wrapper {
        padding: 10px;
        align-items: flex-start;
    }

    .lesson-card {

        padding: 1.5rem;
        border-radius: var(--radius-md);

    }

    .lesson-title {

        font-size: 1.4rem;

    }

    .lesson-actions {

        grid-template-columns: 1fr;

    }

    .lesson-btn {

        padding: 1rem;
        font-size: 0.95rem;

    }

}

/* extra small phones */

@media (max-width: 400px) {

    .lesson-title {

        font-size: 1.2rem;

    }

}