/* =================================================
   Global Variables & Basic Setup
   ================================================= */
:root {
    --primary-yellow: #FFD60A;
    --dark-bg: #111111;
    --surface-bg: #1C1C1C;
    --border-color: #444444;
    --text-primary: #FFFFFF;
    --text-secondary: #A0A0A0;
    --font-primary: 'Poppins', 'Hind Siliguri', sans-serif;
}

/* --- Universal Box Sizing & Responsive Image Reset --- */
*, *::before, *::after {
    box-sizing: border-box;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

body {
    font-family: var(--font-primary);
    background-color: var(--dark-bg);
    color: var(--text-primary);
    margin: 0;
    font-size: 16px;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden; /* Prevents horizontal scroll */
}

.container {
    width: 100%;
    max-width: 1100px;
    margin-left: auto;
    margin-right: auto;
    padding-left: 20px;
    padding-right: 20px;
}

section {
    padding: 60px 0;
}

.highlight-yellow {
    color: var(--primary-yellow);
}

.section-title {
    text-align: center;
    font-size: 28px; /* Mobile first font size */
    margin-top: 0;
    margin-bottom: 40px;
    font-weight: 700;
}

/* =================================================
   Hero Section
   ================================================= */
#hero {
    padding-top: 60px;
    padding-bottom: 60px;
    text-align: center;
}

.chatbot-animation-img {
    width: 120px;
    margin: 0 auto 25px auto;
    animation: float 4s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

.hero-title {
    font-size: 32px;
    margin: 0 0 15px 0;
    font-weight: 700;
    line-height: 1.4;
}

.subtitle {
    font-size: 18px;
    font-weight: 500;
    color: var(--text-secondary);
    margin: 0 auto 30px auto;
    max-width: 600px;
    min-height: 27px;
}

.typewriter-cursor {
    display: inline-block;
    background-color: var(--primary-yellow);
    margin-left: 4px;
    width: 3px;
    animation: blink 1s infinite;
}

@keyframes blink {
    50% { background-color: transparent; }
}

.strong-btn {
    display: inline-block;
    background-color: var(--primary-yellow);
    color: #000000;
    font-weight: 700;
    text-decoration: none;
    padding: 15px 40px;
    border-radius: 8px;
    text-align: center;
    font-size: 18px;
    transition: all 0.2s ease-in-out;
    border: none;
    cursor: pointer;
}

.strong-btn:hover {
    transform: scale(1.05);
    filter: brightness(1.1);
}

/* =================================================
   Instructor Section
   ================================================= */
.instructor-flex {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 30px;
    background-color: var(--surface-bg);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 30px 20px;
    max-width: 800px;
    margin: 0 auto;
}

.instructor-img {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--primary-yellow);
}

.instructor-details h3 {
    margin-top: 0;
    font-size: 24px;
}

.instructor-title {
    font-weight: 600;
    color: var(--primary-yellow);
    margin: -5px 0 15px 0;
}

.instructor-bio {
    color: var(--text-secondary);
    font-size: 15px;
}

/* =================================================
   Features Section
   ================================================= */
#features {
    background-color: var(--surface-bg);
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}

.modern-card {
    background: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    transition: all 0.3s ease;
}

.modern-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary-yellow);
}

.modern-card h3 {
    font-size: 18px;
    margin: 0 0 8px 0;
}

.modern-card p {
    color: var(--text-secondary);
    font-size: 14px;
    margin: 0;
}

/* =================================================
   Enrollment Form Section
   ================================================= */
.enroll-container {
    max-width: 600px;
    text-align: center;
    margin: auto;
}

.price-box {
    margin-bottom: 30px;
    padding: 15px 25px;
    border: 1px solid var(--border-color);
    background-color: var(--surface-bg);
    border-radius: 10px;
    display: inline-block;
}

.old-price {
    font-size: 18px;
    text-decoration: line-through;
    color: var(--text-secondary);
    margin-right: 15px;
}

.new-price {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-yellow);
}

.form-group {
    margin-bottom: 20px;
}

.form-control {
    width: 100%;
    padding: 16px 20px;
    background-color: var(--surface-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 16px;
}

.form-control::placeholder {
    color: var(--text-secondary);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-yellow);
    box-shadow: 0 0 10px rgba(255, 214, 10, 0.2);
}

.form-submit-btn {
    width: 100%;
}


/* =================================================
   Payment Modal (Popup) Styles
   ================================================= */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.8);
    align-items: center;
    justify-content: center;
    padding: 20px;
    animation: fadeInBg 0.3s;
}

.modal-content {
    background-color: #1C1C1C;
    padding: 30px;
    border: 1px solid var(--border-color);
    width: 100%;
    max-width: 450px;
    border-radius: 12px;
    text-align: center;
    position: relative;
    animation: fadeInModal 0.4s ease-out;
}

@keyframes fadeInBg {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes fadeInModal {
    from { opacity: 0; transform: translateY(-30px) scale(0.95); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

.close-btn {
    color: var(--text-secondary);
    position: absolute;
    top: 10px;
    right: 20px;
    font-size: 32px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.2s;
}

.close-btn:hover,
.close-btn:focus {
    color: var(--text-primary);
}

.modal-content h3 {
    color: var(--text-primary);
    margin-top: 0;
    margin-bottom: 25px;
    font-size: 22px;
}

.payment-options {
    margin-top: 15px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.payment-btn {
    flex: 1;
    padding: 15px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background-color: #2a2a2a;
    color: var(--text-primary);
}

.payment-btn:hover {
    transform: translateY(-3px);
    border-color: var(--primary-yellow);
    color: var(--primary-yellow);
}

.payment-btn img {
    height: 24px;
}


/* =================================================
   Footer
   ================================================= */
footer {
    padding: 30px 0;
    background-color: #000000;
    font-size: 14px;
    color: var(--text-secondary);
    text-align: center;
}


/* =================================================
   MEDIA QUERIES FOR LARGER SCREENS (Desktop)
   ================================================= */
/* Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {
    section {
        padding: 80px 0;
    }
    
    .section-title {
        font-size: 32px;
    }

    .hero-title {
        font-size: 38px;
    }

    .instructor-flex {
        flex-direction: row;
        text-align: left;
        gap: 40px;
        padding: 40px;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 25px;
    }

    .payment-options {
        flex-direction: row;
    }
}

/* Large devices (desktops, 992px and up) */
@media (min-width: 992px) {
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}