/* ============================================= */
/* Course Grid 2x2 - Professional & Beginner-friendly */
/* ============================================= */
.course-grid-section {
    position: relative;
    padding: 5rem 0 4rem;
    overflow: hidden;
}

/* Stats bar */
.course-stats {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 2.5rem;
    flex-wrap: wrap;
}

.course-stat-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--muted);
    font-size: 0.9rem;
}

.course-stat-item .stat-value {
    font-size: 1.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--emerald), #34d399);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    font-family: var(--font-mono, 'JetBrains Mono', monospace);
}

.stat-divider {
    width: 1px;
    height: 2rem;
    background: rgba(255, 255, 255, 0.1);
}

/* 2x2 Grid */
.course-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
    max-width: 1100px;
    margin: 3rem auto 0;
    position: relative;
}

/* Center cross connector */
.course-grid::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 10%;
    right: 10%;
    height: 1px;
    background: linear-gradient(to right, rgba(16, 185, 129, 0) 0%, rgba(16, 185, 129, 0.25) 30%, rgba(16, 185, 129, 0.25) 70%, rgba(16, 185, 129, 0) 100%);
    z-index: 0;
}

.course-grid::after {
    content: '';
    position: absolute;
    left: 50%;
    top: 10%;
    bottom: 10%;
    width: 1px;
    background: linear-gradient(to bottom, rgba(16, 185, 129, 0) 0%, rgba(16, 185, 129, 0.25) 30%, rgba(16, 185, 129, 0.25) 70%, rgba(16, 185, 129, 0) 100%);
    z-index: 0;
}

/* Center node */
.course-grid-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--card);
    border: 2px solid var(--emerald);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 3;
    box-shadow: 0 0 24px rgba(16, 185, 129, 0.3), 0 0 60px rgba(16, 185, 129, 0.1);
}

.course-grid-center i {
    color: var(--emerald);
    width: 20px;
    height: 20px;
}

/* Phase card */
.phase-card {
    position: relative;
    z-index: 1;
    background: linear-gradient(145deg, rgba(30, 41, 59, 0.5) 0%, rgba(15, 23, 42, 0.5) 100%);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 1.25rem;
    padding: 2rem;
    backdrop-filter: blur(12px);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 8px 32px -8px rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.phase-card::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 1.25rem;
    padding: 1px;
    background: linear-gradient(135deg, transparent, rgba(255, 255, 255, 0.05), transparent);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    pointer-events: none;
}

.phase-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 20px 50px -12px rgba(0, 0, 0, 0.6);
}

/* Per-card accent color on hover */
.phase-card[data-accent="emerald"]:hover {
    border-color: rgba(16, 185, 129, 0.35);
    box-shadow: 0 20px 50px -12px rgba(16, 185, 129, 0.15);
}
.phase-card[data-accent="gold"]:hover {
    border-color: rgba(250, 204, 21, 0.35);
    box-shadow: 0 20px 50px -12px rgba(250, 204, 21, 0.12);
}
.phase-card[data-accent="cyan"]:hover {
    border-color: rgba(56, 189, 248, 0.35);
    box-shadow: 0 20px 50px -12px rgba(56, 189, 248, 0.12);
}
.phase-card[data-accent="red"]:hover {
    border-color: rgba(239, 68, 68, 0.3);
    box-shadow: 0 20px 50px -12px rgba(239, 68, 68, 0.12);
}

/* Phase header */
.phase-header {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 1.25rem;
}

.phase-icon-box {
    flex-shrink: 0;
    width: 52px;
    height: 52px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.3s ease;
}

.phase-card:hover .phase-icon-box {
    transform: scale(1.08);
}

.phase-icon-box i {
    width: 24px;
    height: 24px;
}

.phase-icon-box.emerald {
    background: rgba(16, 185, 129, 0.12);
    border: 1px solid rgba(16, 185, 129, 0.25);
}
.phase-icon-box.emerald i { color: var(--emerald); }

.phase-icon-box.gold {
    background: rgba(250, 204, 21, 0.1);
    border: 1px solid rgba(250, 204, 21, 0.25);
}
.phase-icon-box.gold i { color: var(--gold); }

.phase-icon-box.cyan {
    background: rgba(56, 189, 248, 0.1);
    border: 1px solid rgba(56, 189, 248, 0.25);
}
.phase-icon-box.cyan i { color: #38bdf8; }

.phase-icon-box.red {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.25);
}
.phase-icon-box.red i { color: #ef4444; }

.phase-meta {
    flex: 1;
}

.phase-number {
    font-size: 0.7rem;
    letter-spacing: 0.12em;
    font-weight: 700;
    text-transform: uppercase;
    margin-bottom: 0.25rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.phase-duration {
    font-size: 0.65rem;
    padding: 0.15rem 0.6rem;
    border-radius: 9999px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--muted);
    font-weight: 600;
    letter-spacing: 0.02em;
    white-space: nowrap;
}

.phase-title {
    font-size: 1.15rem;
    font-weight: 700;
    color: white;
    line-height: 1.35;
}

/* Friendly subtitle */
.phase-outcome {
    font-size: 0.85rem;
    color: var(--muted);
    line-height: 1.6;
    margin-bottom: 1.25rem;
    padding-bottom: 1.25rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.phase-outcome strong {
    color: rgba(255, 255, 255, 0.85);
    font-weight: 600;
}

/* Skill tags */
.phase-skills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-top: auto;
}

.skill-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 0.3rem 0.7rem;
    border-radius: 0.5rem;
    font-size: 0.75rem;
    font-weight: 500;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: var(--muted);
    transition: all 0.2s ease;
}

.skill-tag:hover {
    background: rgba(255, 255, 255, 0.08);
    color: white;
}

.skill-tag i {
    width: 12px;
    height: 12px;
    opacity: 0.7;
}

/* Course CTA area */
.course-cta-area {
    text-align: center;
    margin-top: 3rem;
}

.course-cta-area .cta-hint {
    display: block;
    font-size: 0.8rem;
    color: var(--muted);
    margin-top: 0.75rem;
}

/* Responsive */
@media (max-width: 768px) {
    .course-grid {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

    .course-grid::before,
    .course-grid::after,
    .course-grid-center {
        display: none;
    }

    .phase-card {
        padding: 1.5rem;
    }

    .phase-title {
        font-size: 1.05rem;
    }

    .course-stats {
        gap: 1rem;
    }

    .course-stat-item .stat-value {
        font-size: 1.25rem;
    }

    .course-stat-item {
        font-size: 0.8rem;
    }
}

@media (min-width: 769px) and (max-width: 992px) {
    .course-grid {
        gap: 1.25rem;
    }

    .phase-card {
        padding: 1.75rem;
    }
}