h1 {
    margin-bottom: 80px;
}
#roadmap-container {
    position: relative;
    width: 100%;
    aspect-ratio: 1/1;
    box-sizing: border-box;
    background-repeat: no-repeat;
    background-size: 100% auto;
    background-position: top center;
}

#roadmap-container h1 {
    text-align: center;
    font-family: var(--font-titles);
    color: var(--text-dark);
    margin-bottom: 80px;
    font-size: 5.5rem;
}

#roadmap-container .semester {
    position: absolute;
    display: flex;
    align-items: flex-start;
    gap: 15px;
}


/* semester border animation hover effect */
@property --angle {
    syntax: '<angle>';
    initial-value: 0deg;
    inherits: false;
}
#roadmap-container .semester::after, #roadmap-container .semester::before {
    display: none;
    content: '';
    position: absolute;
    height: 100%;
    width: 100%;
    background-image: conic-gradient(from var(--angle), transparent 70%, var(--primary-saturated));
    top: 50%;
    left: 50%;
    translate: -50% -50%;
    z-index: 0;
    padding: 3px;
    border-radius: 10px;
}
#roadmap-container .semester::before {
    filter: blur(1rem);
    opacity: 0.5;
}
#roadmap-container .semester:hover::after, #roadmap-container .semester:hover::before {
    display: block;
    animation: 3s spin linear infinite;
}
@keyframes spin {
    from {
        --angle: 0deg;
    }
    to {
        --angle: 360deg;
    }
}


#roadmap-container .semester-info {
    background-color: var(--text-light);
    padding: 10px 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    color: var(--text-dark);
    font-family: var(--font-text-secondary);
    font-weight: bold;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 5px;
    cursor: pointer;
    width: fit-content;
    box-sizing: border-box;
    transition: 0.4s;
    z-index: 10;
}
#roadmap-container .semester-info:hover {
    /* translate: 0 -5px; */
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}
#roadmap-container .pin {
    position: absolute;
    width: 40px;
    aspect-ratio: 1/1;
    /* A simple pin SVG similar to the one in the image */
    background-size: contain;
    background-repeat: no-repeat;
    transform: translate(-50%, -50%);
    transition: 0.5s;
    cursor: pointer;
    z-index: 5;
}
#roadmap-container .pin:hover {
    opacity: 0.9;
}

#roadmap-container .semester-header {
    display: flex;
    justify-content: left;
    align-items: center;
    gap: 30px;
    padding: 10px;
}
#roadmap-container .semester-header h3 {
    margin: 0;
    font-size: 2.2rem;
    color: var(--text-dark);
    font-family: var(--font-titles);
}
#roadmap-container .semester-number {
    flex-shrink: 0;
    width: 30px;
    aspect-ratio: 1/1;
    border-radius: 50%;
    background-color: var(--primary-saturated);
    color: var(--text-light);
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: var(--font-titles);
    font-size: 1.9rem;
    font-weight: normal;
    z-index: 10;
}
#roadmap-container #semester2, #roadmap-container #semester4, #roadmap-container #semester6 { --primary-saturated: var(--accent); }
#roadmap-container #semester2 .pin, #roadmap-container #semester4 .pin, #roadmap-container #semester6 .pin { filter: invert(1); }
/* Semester Specific Positioning and Rotation */
/* These values are estimated and will need fine-tuning to match the image exactly. */
/* They are set for a desktop-first design, assuming a wide viewport. */

#roadmap-container #semester1 { top: 4.5%; left: 28%; z-index: 5; }
#roadmap-container #semester1 .pin { top: -5rem; left: -5rem; transform: rotate(-5deg); }

#roadmap-container #semester2 { top: 26%; left: 55%; z-index: 4; }
#roadmap-container #semester2 .pin { top: -5rem; left: -5rem; transform: rotate(5deg); }

#roadmap-container #semester3 { top: 40%; left: 18%; z-index: 3; }
#roadmap-container #semester3 .pin { top: -5rem; left: -5rem; transform: rotate(-5deg); }

#roadmap-container #semester4 { top: 53%; right: 19%; z-index: 2; }
#roadmap-container #semester4 .pin { top: -60px; right: -65px; transform: rotate(-5deg); }

#roadmap-container #semester5 { top: 72%; left: 50%; z-index: 1; }
#roadmap-container #semester5 .pin { top: -5rem; left: -5rem; transform: rotate(5deg); }

#roadmap-container #semester6 { top: 82%; left: 12%; z-index: 0; }
#roadmap-container #semester6 .pin { top: -5rem; left: -5rem; transform: rotate(0deg); }

/* General styles for courses toggle (renamed from .semester-5-courses) */
#roadmap-container .semester-courses {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transform-origin: top;
    transform: scaleY(0);
    transition: 0.8s;
    width: 100%;
    box-sizing: border-box;
}
#roadmap-container .semester-courses.show {
    max-height: 300px;
    opacity: 1;
    padding: 15px 0;
    transform: scaleY(1);
}

#roadmap-container .course-button {
    background-color: var(--primary-saturated);
    opacity: 0.6;
    color: var(--text-light);
    padding: 8px 15px;
    border-radius: 15px;
    text-align: center;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.6rem;
    font-weight: bold;
    cursor: pointer;
    transition: 0.3s ease, transform 0.2s ease;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
#roadmap-container .course-button:hover {
    opacity: 1;
    transform: translateY(-2px);
}
#roadmap-container .course-button.inactive {
    filter: saturate(0.2);
    cursor: auto;
}
#roadmap-container .course-button.inactive:hover {
    filter: saturate(0.2);
    opacity: 0.6;
    transform: none;
}


/* mobile styling */
@media (max-width: 1000px) {
    h1 {
        margin-top: 20px;
    }
    #roadmap-container .semester-header {
        justify-content: center;
        margin: auto;
    }
    #roadmap-container .semester-header h3 {
        font-size: 2.7rem;
    }
    #roadmap-container .pin {
        width: 30px;
    }


    /* fixing roadmap container aspect ratio */
    #roadmap-container {
        /* 1/3 is the aspect ratio of the mobile road bg image */
        /* aspect ratio is used here so that roadmap container is exactly the same size as the image */
        /* which is necessary for the positioning of the semesters and pins */
        aspect-ratio: 1/3;
        margin: 30px auto;
        margin-bottom: 0;
    }
    /* positioning semesters with their pins */
    #roadmap-container #semester1 { top: 12%; right: 20%; left: auto; }
    #roadmap-container #semester1 .pin { top: -4rem; right: -50px; left: auto; transform: rotate(10deg); }

    #roadmap-container #semester2 { top: 26%; left: 18%; right: auto; }
    #roadmap-container #semester2 .pin { top: -4rem; left: -4rem; right: auto; transform: rotate(-10deg); }

    #roadmap-container #semester3 { top: 40%; right: 20%; left: auto; }
    #roadmap-container #semester3 .pin { top: -4rem; right: -50px; left: auto; transform: rotate(10deg); }

    #roadmap-container #semester4 { top: 58%; left: 18%; right: auto; }
    #roadmap-container #semester4 .pin { top: -4rem; left: -4rem; right: auto; transform: rotate(-10deg); }

    #roadmap-container #semester5 { top: 72%; right: 20%; left: auto; }
    #roadmap-container #semester5 .pin { top: -4rem; right: -50px; left: auto; transform: rotate(10deg); }

    #roadmap-container #semester6 { top: 82%; right: 20%; left: auto; }
    #roadmap-container #semester6 .pin { top: -4rem; right: -50px; left: auto; transform: rotate(0deg); }

    /* fixing gaps & padding */
    #roadmap-container .semester-header {
        gap: 15px;
        padding: 5px;
    }
    #roadmap-container .semester-info {
        padding: 8px 16px;
    }
    #roadmap-container .semester-courses {
        gap: 6px;
    }
    #roadmap-container .course-button {
        padding: 6px 12px;
    }
}