:root{
    --primary-color: #0a486ff7;
    --secondary-color: #6c757d;
    --background-color: #f8f9fa;
    --text-color: #343a40;
    --border-color: #dee2e6;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --header-bg: #ffffff;
    --hero-gradient-start: #0a486f;
    --hero-gradient-end: #021521;
    --hero-accent: rgba(255, 255, 255, 0.08);
    --signup-btn-color: #28a745;
    --create-course-btn-color: #ff6b35;
    --font-display: 'Plus Jakarta Sans', 'Roboto', sans-serif;
    --font-body: 'Plus Jakarta Sans', 'Roboto', sans-serif;
    --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-out-quart: cubic-bezier(0.25, 1, 0.5, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Hide scrollbar for all browsers */
html {
    scrollbar-width: none; /* Firefox */
    -ms-overflow-style: none; /* IE and Edge */
    scroll-behavior: smooth;
}

html::-webkit-scrollbar {
    display: none; /* Chrome, Safari, Opera */
}

body{
    background-color: var(--header-bg);
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.5;
    color: var(--text-color);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    width: 100%;
    overflow-x: hidden;
    scrollbar-width: none; /* Firefox */
    -ms-overflow-style: none; /* IE and Edge */
}

body::-webkit-scrollbar {
    display: none; /* Chrome, Safari, Opera */
}

/* Header Styles */
.header{
    background-color: var(--header-bg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 3rem;
    width: 100%;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    position: relative;
    z-index: 100;
    flex-wrap: wrap;
}

.logo-class{
    display: flex;
    align-items: center;
    gap: 0.75rem;
    flex-shrink: 0;
}

.logo-class img{
    width: 120px;
    height: auto;
    max-width: 100%;
    object-fit: contain;
}

/* Mobile Menu Toggle Button */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 44px;
    height: 44px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    gap: 5px;
    z-index: 101;
    order: 3;
}

.hamburger-line {
    width: 24px;
    height: 3px;
    background-color: var(--primary-color);
    border-radius: 2px;
    transition: all 0.3s ease;
}

.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--text-color);
    letter-spacing: -0.5px;
}

.Options-Class{
    display: flex;
    flex-direction: row;
    gap: 2.5rem;
    align-items: center;
    flex: 1;
    justify-content: center;
}

.Options-Class .nav-link {
    text-decoration: none;
    color: var(--primary-color);
    font-size: 0.95rem;
    font-weight: semibold;
    transition: color 0.3s ease-in-out;
    position: relative;
    padding-bottom: 4px;
}

.Options-Class .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease-in-out;
}

.Options-Class .nav-link:hover {
    font-weight: bold;
}

.Options-Class .nav-link:hover::after {
    width: 100%;
}

.Options-Class .nav-link.active {
    font-weight: bold;
}

.Options-Class .nav-link.active::after {
    width: 100%;
}

.Action-class{
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.sign-in-link {
    text-decoration: none;
    color: var(--primary-color);
    font-size: 0.95rem;
    font-weight: bold;
    transition: opacity 0.3s ease-in-out;
    padding: 0.6rem 1.5rem;
}

.sign-in-link:hover {
    background-color: var(--primary-color);
    color: white;
    transition: background-color 0.3s ease, transform 0.2s ease;
    border-radius: 25px;
}

.sign-up-btn {
    background-color: white;
    color: var(--success-color);
    padding: 0.6rem 1.5rem;
    border-radius: 25px;
    text-decoration: none;
    border: 1px solid var(--success-color);
    font-size: 0.95rem;
    font-weight: bold;
    transition: background-color 0.3s ease, transform 0.2s ease;
    display: inline-block;
}

.sign-up-btn:hover {
    background-color: #218838;
    transform: translateY(-1px);
    color: white;
    text-decoration: none;
}

/* User Profile Dropdown */
.user-profile-dropdown {
    position: relative;
}

.user-profile-trigger {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: none;
    border: 1px solid #e9ecef;
    border-radius: 25px;
    padding: 0.5rem 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: 'Roboto', sans-serif;
}

.user-profile-trigger:hover {
    background-color: #f8f9fa;
    border-color: var(--primary-color);
}

.user-profile-trigger.active {
    background-color: #f8f9fa;
    border-color: var(--primary-color);
}

.user-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color) 0%, #083d5f 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 0.9rem;
    flex-shrink: 0;
}

.avatar-initials {
    display: block;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.user-name {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-color);
    white-space: nowrap;
    max-width: 150px;
    overflow: hidden;
    text-overflow: ellipsis;
}

.user-profile-trigger .bi-chevron-down {
    font-size: 0.75rem;
    color: var(--text-color);
    transition: transform 0.3s ease;
}

.user-profile-trigger.active .bi-chevron-down {
    transform: rotate(180deg);
}

.user-profile-menu {
    position: absolute;
    top: calc(100% + 0.5rem);
    right: 0;
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    min-width: 220px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    z-index: 1000;
    overflow: hidden;
}

.user-profile-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.profile-menu-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1.25rem;
    color: var(--text-color);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 400;
    transition: all 0.2s ease;
    border-bottom: 1px solid #f1f3f5;
}

.profile-menu-item:last-child {
    border-bottom: none;
}

.profile-menu-item:hover {
    background-color: #f8f9fa;
    color: var(--primary-color);
    text-decoration: none;
}

.profile-menu-item.logout-item {
    color: var(--danger-color);
    border-top: 1px solid #f1f3f5;
    margin-top: 0.25rem;
}

.profile-menu-item.logout-item:hover {
    background-color: #fff5f5;
    color: var(--danger-color);
}

.profile-menu-item i {
    font-size: 1.1rem;
    width: 20px;
    text-align: center;
}

.profile-menu-divider {
    height: 1px;
    background-color: #e9ecef;
    margin: 0.5rem 0;
}

/* Responsive User Profile */
@media (max-width: 768px) {
    .user-name {
        display: none;
    }
    
    .user-profile-trigger {
        padding: 0.5rem;
    }
    
    .user-profile-menu {
        right: 0;
        left: auto;
        min-width: 200px;
    }
}

/* Hero Section - Tall hero; courses still visible below */
.hero-section {
    position: relative;
    min-height: 520px;
    max-height: 75vh;
    max-height: 75dvh;
    width: 100%;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0;
    isolation: isolate;
}

.hero-section::before{
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url("/static/authentication/images/study_group.72c208c32fff.jpg") no-repeat center center;
    background-size: cover;
    z-index: -2;
    will-change: transform;
    transform: translateZ(0);
    animation: hero-bg-zoom 20s ease-out forwards;
}
@keyframes hero-bg-zoom {
    0% { transform: translateZ(0) scale(1.05); }
    100% { transform: translateZ(0) scale(1); }
}

.hero-section::after{
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--hero-gradient-start) 0%, var(--hero-gradient-end) 50%, #021521 100%);
    opacity: 0.92;
    z-index: -1;
}

/* Subtle grid overlay for depth */
.hero-section .hero-background {
    position: absolute;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    background-image: linear-gradient(var(--hero-accent) 1px, transparent 1px), linear-gradient(90deg, var(--hero-accent) 1px, transparent 1px);
    background-size: 60px 60px;
    opacity: 0.4;
}

.hero-content {
    position: relative;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    margin: 0 auto;
    padding: clamp(1.5rem, 4vw, 3rem) clamp(1.5rem, 6vw, 5rem);
    gap: clamp(2rem, 4vw, 3rem);
    min-height: 0;
}

.hero-text {
    flex: 2;
    color: white;
    text-align: left;
    max-width: 100%;
}

.hero-title {
    font-family: var(--font-display);
    font-size: clamp(1.9rem, 4.2vw, 3rem);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
    color: white;
    word-wrap: break-word;
    opacity: 0;
    transform: translateY(24px);
    animation: hero-fade-up 0.8s var(--ease-out-expo) 0.15s forwards;
}
.hero-title-line {
    display: block;
}
.title-line-2 {
    display: block;
}

.hero-description {
    font-family: var(--font-body);
    font-size: clamp(0.9rem, 1.9vw, 1.1rem);
    line-height: 1.65;
    margin-bottom: 1.5rem;
    color: rgba(255, 255, 255, 0.9);
    font-weight: 400;
    opacity: 0;
    transform: translateY(20px);
    animation: hero-fade-up 0.7s var(--ease-out-expo) 0.35s forwards;
}
.hero-description strong {
    font-weight: 600;
    color: white;
}

@keyframes hero-fade-up {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    opacity: 0;
    transform: translateY(16px);
    animation: hero-fade-up 0.6s var(--ease-out-expo) 0.5s forwards;
}

.btn-signup,
.btn-create-course {
    padding: 0.95rem 2rem;
    border-radius: 12px;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 600;
    font-family: var(--font-body);
    transition: transform 0.35s var(--ease-out-quart), box-shadow 0.35s ease, background 0.25s ease;
    display: inline-block;
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}
.btn-signup::after,
.btn-create-course::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(120deg, transparent, rgba(255,255,255,0.2), transparent);
    transform: translateX(-100%);
    transition: transform 0.5s ease;
}
.btn-signup:hover::after,
.btn-create-course:hover::after {
    transform: translateX(100%);
}

.btn-signup {
    background: linear-gradient(135deg, #2ecc71 0%, #27ae60 100%);
    color: white;
    box-shadow: 0 4px 14px rgba(39, 174, 96, 0.35);
}
.btn-signup:hover {
    background: linear-gradient(135deg, #27ae60 0%, #219a52 100%);
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(39, 174, 96, 0.45);
    color: white;
    text-decoration: none;
}
.btn-signup:active {
    transform: translateY(-1px);
}

.btn-create-course {
    background: linear-gradient(135deg, #ff7b54 0%, #f25c3d 100%);
    color: white;
    box-shadow: 0 4px 14px rgba(242, 92, 61, 0.35);
}
.btn-create-course:hover {
    background: linear-gradient(135deg, #f25c3d 0%, #e04a2a 100%);
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(242, 92, 61, 0.45);
    color: white;
    text-decoration: none;
}
.btn-create-course:active {
    transform: translateY(-1px);
}

.btn-signup:focus-visible,
.btn-create-course:focus-visible {
    outline: 2px solid white;
    outline-offset: 3px;
}
.hero-scroll-hint:focus-visible {
    outline: 2px solid rgba(255,255,255,0.8);
    outline-offset: 2px;
}

/* Scroll-to-courses hint - pill with glass effect */
.hero-scroll-hint {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    margin-top: 1rem;
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    padding: 0.5rem 0.9rem;
    border-radius: 999px;
    border: 1px solid rgba(255,255,255,0.25);
    background: rgba(255,255,255,0.06);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: color 0.25s ease, transform 0.25s ease, background 0.25s ease, border-color 0.25s ease;
    opacity: 0;
    animation: hero-fade-up 0.6s var(--ease-out-expo) 0.65s forwards;
}
.hero-scroll-hint:hover {
    color: white;
    text-decoration: none;
    background: rgba(255,255,255,0.12);
    border-color: rgba(255,255,255,0.4);
    transform: translateY(3px);
}
.hero-scroll-hint .bi-chevron-down {
    font-size: 1.1rem;
    transition: transform 0.3s var(--ease-out-quart);
}
.hero-scroll-hint:hover .bi-chevron-down {
    transform: translateY(3px);
}
@keyframes bounce-down {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(4px); }
}
.hero-scroll-hint .bi-chevron-down {
    animation: bounce-down 2.2s ease-in-out infinite;
}

/* Robot Section - with glow and entrance */
.hero-robot {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    min-height: 260px;
    max-height: 58vh;
    opacity: 0;
    transform: translateX(24px);
    animation: hero-fade-up 0.9s var(--ease-out-expo) 0.25s forwards;
}
.hero-robot .robot-glow {
    position: absolute;
    width: 70%;
    height: 70%;
    max-width: 260px;
    max-height: 260px;
    background: radial-gradient(circle, rgba(10, 72, 111, 0.45) 0%, transparent 70%);
    border-radius: 50%;
    filter: blur(36px);
    pointer-events: none;
    animation: glow-pulse 4s ease-in-out infinite;
}
@keyframes glow-pulse {
    0%, 100% { opacity: 0.55; transform: scale(1); }
    50% { opacity: 0.85; transform: scale(1.06); }
}

.robot-image {
    width: 100%;
    max-width: 380px;
    height: auto;
    object-fit: contain;
    filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.25));
    animation: float 4s ease-in-out infinite;
    position: relative;
    z-index: 2;
    will-change: transform;
}

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

/* Respect reduced motion preference */
@media (prefers-reduced-motion: reduce) {
    .hero-section::before {
        animation: none;
    }
    .hero-title,
    .hero-description,
    .hero-buttons,
    .hero-scroll-hint,
    .hero-robot {
        animation: none;
        opacity: 1;
        transform: none;
    }
    .robot-image {
        animation: none;
    }
    .hero-robot .robot-glow {
        animation: none;
    }
    .btn-signup::after,
    .btn-create-course::after {
        display: none;
    }
}


/* Responsive Design */

/* Large Desktop (1400px+) - Default styles above */

/* Desktop (1200px - 1399px) */
@media (max-width: 1399px) {
    .header {
        padding: 1rem 2rem;
    }
    
    .hero-content {
        padding: 3rem 4rem;
    }
}

/* Tablet Landscape / Small Desktop (992px - 1199px) */
@media (max-width: 1199px) {
    .header {
        padding: 1rem 1.5rem;
    }
    
    .Options-Class {
        gap: 1.5rem;
    }
    
    .hero-content {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
        padding: 1.5rem 2rem;
    }
    
    .hero-text {
        max-width: 100%;
        text-align: center;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-scroll-hint {
        justify-content: center;
    }
    
    .hero-robot {
        min-height: 180px;
        max-height: 42vh;
    }
    
    .robot-image {
        max-width: 300px;
    }
}

/* External Courses Section - compact so courses appear in first viewport */
#courses-section {
    scroll-margin-top: 80px;
}
.externals-section {
    background-color: white;
    padding: clamp(1rem, 2.5vw, 1.75rem) 0 clamp(2rem, 4vw, 4rem);
    width: 100%;
    min-height: auto;
    height: auto;
}

.search-bar-container {
    padding: 0 clamp(1.5rem, 5vw, 5rem);
    margin-bottom: clamp(0.75rem, 2vw, 1.5rem);
}

.search-form {
    display: flex;
    align-items: center;
    gap: 1rem;
    max-width: 800px;
    margin: 0 auto;
}

.search-input {
    flex: 1;
    padding: 1rem 1.5rem;
    border: 2px solid #e9ecef;
    border-radius: 12px;
    font-size: 1rem;
    font-family: 'Roboto', sans-serif;
    color: var(--text-color);
    background-color: white;
    transition: all 0.3s ease;
    outline: none;
}

.search-input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(10, 72, 111, 0.1);
}

.search-input::placeholder {
    color: #adb5bd;
}

.search-btn {
    padding: 1rem 2.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 500;
    font-family: 'Roboto', sans-serif;
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.search-btn:hover {
    background-color: #083d5f;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(10, 72, 111, 0.3);
}

.search-btn:active {
    transform: translateY(0);
}

.externals-title {
    font-size: clamp(1.35rem, 3.5vw, 2rem);
    font-weight: 700;
    color: var(--text-color);
    margin-bottom: clamp(0.75rem, 2vw, 1.25rem);
    padding: 0 clamp(1.5rem, 5vw, 5rem);
}

.courses-scroll-container {
    overflow-x: hidden;
    overflow-y: auto;
    max-height: 70vh;
    padding: 0 clamp(1.5rem, 5vw, 5rem) 1.5rem;
    scrollbar-width: thin;
    scrollbar-color: rgba(0, 0, 0, 0.2) transparent;
    -webkit-overflow-scrolling: touch;
    scroll-behavior: smooth;
}

.courses-scroll-container::-webkit-scrollbar {
    width: 8px;
}

.courses-scroll-container::-webkit-scrollbar-track {
    background: transparent;
}

.courses-scroll-container::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 4px;
}

.courses-scroll-container::-webkit-scrollbar-thumb:hover {
    background: rgba(0, 0, 0, 0.3);
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(min(320px, 100%), 1fr));
    gap: 2rem;
    padding-bottom: 1rem;
}

.course-card-external {
    width: 100%;
    min-width: 0;
    max-width: 380px;
    margin: 0 auto;
    background: white;
    border-radius: 16px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    /* Optimize hover animation */
    will-change: transform, box-shadow;
}

.course-card-external:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

/* Disable hover effects on touch devices */
@media (hover: none) {
    .course-card-external:hover {
        transform: none;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    }
}

.course-card-image-container {
    width: 100%;
    aspect-ratio: 16 / 10;
    overflow: hidden;
    background: linear-gradient(135deg, #f5f7fa 0%, #e8ecf1 100%);
    position: relative;
}

.course-card-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
    /* Optimize image loading */
    content-visibility: auto;
}

.course-card-external:hover .course-card-img {
    transform: scale(1.05);
}

.course-card-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(10, 72, 111, 0.1) 0%, rgba(10, 72, 111, 0.05) 100%);
    color: var(--primary-color);
    font-size: 4rem;
}

.course-card-content {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.course-card-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.75rem;
    line-height: 1.4;
}

.course-card-description {
    font-size: 0.9rem;
    color: #6c757d;
    line-height: 1.6;
    margin-bottom: 0.75rem;
    flex-grow: 1;
}

.course-card-link {
    font-size: 0.85rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-weight: 500;
}

.course-card-provider {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.25rem;
    padding-top: 1rem;
    border-top: 1px solid #e9ecef;
}

.provider-logo {
    width: 40px;
    height: 40px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.provider-logo img {
    width: 100%;
    height: 100%;
    object-fit: fill;
    padding: 4px;
}
    
.provider-name {
    font-size: 0.9rem;
    color: var(--text-color);
    font-weight: 500;
}

.btn-get-started {
    background-color: var(--primary-color);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    text-align: center;
    transition: all 0.3s ease;
    align-self: flex-end;
    margin-top: auto;
}

.btn-get-started:hover {
    background-color: #083d5f;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(10, 72, 111, 0.3);
    color: white;
    text-decoration: none;
}

.no-courses {
    padding: 3rem;
    text-align: center;
    color: var(--text-color);
    font-size: 1.1rem;
}

/* Tablet Portrait (768px - 991px) */
@media (max-width: 991px) {
    .header {
        padding: 0.75rem 1.5rem;
    }
    
    /* Show mobile menu toggle */
    .mobile-menu-toggle {
        display: flex;
    }
    
    /* Hide desktop navigation */
    .Options-Class {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem 1.5rem;
        gap: 0;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        border-top: 1px solid #e9ecef;
    }
    
    .Options-Class.mobile-open {
        display: flex;
    }
    
    .Options-Class .nav-link {
        padding: 1rem 0;
        border-bottom: 1px solid #f1f3f5;
        width: 100%;
    }
    
    .Options-Class .nav-link:last-child {
        border-bottom: none;
    }
    
    .Action-class {
        display: none;
        position: absolute;
        top: calc(100% + 140px);
        left: 0;
        right: 0;
        background: white;
        padding: 1rem 1.5rem;
        flex-direction: column;
        gap: 1rem;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        border-top: 1px solid #e9ecef;
    }
    
    .Action-class.mobile-open {
        display: flex;
    }
    
    .Action-class .sign-in-link,
    .Action-class .sign-up-btn {
        width: 100%;
        text-align: center;
    }
    
    .logo-class img {
        width: 100px;
    }
    
    .hero-content {
        padding: 2rem 1.5rem;
        min-height: auto;
    }
    
    .hero-robot {
        min-height: 250px;
        max-height: 350px;
    }
    
    .robot-image {
        max-width: 300px;
    }
    
    .search-form {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .search-input,
    .search-btn {
        width: 100%;
    }
    
    .course-card-external {
        max-width: min(340px, 80vw);
    }
}

/* Mobile Landscape / Large Mobile (576px - 767px) */
@media (max-width: 767px) {
    .header {
        padding: 0.75rem 1rem;
    }
    
    .logo-class img {
        width: 90px;
    }
    
    .hero-content {
        padding: 1.5rem 1rem;
        gap: 1.5rem;
    }
    
    .hero-text {
        text-align: center;
    }
    
    .hero-buttons {
        flex-direction: column;
        width: 100%;
        gap: 0.75rem;
    }
    
    .btn-signup,
    .btn-create-course {
        width: 100%;
        text-align: center;
        padding: 0.875rem 1.5rem;
    }
    
    .hero-robot {
        min-height: 200px;
        max-height: 280px;
    }
    
    .robot-image {
        max-width: 250px;
    }
    
    .course-card-external {
        max-width: min(300px, 85vw);
    }
    
    .course-card-content {
        padding: 1.25rem;
    }
    
    .course-card-title {
        font-size: 1.1rem;
    }
}

/* Footer Styles */
.footer {
    background-color: var(--primary-color);
    color: white;
    width: 100%;
    padding: clamp(2rem, 4vw, 4rem) 0 2rem;
}

.footer-container {
    max-width: 100%;
    margin: 0 auto;
    padding: 0 clamp(1.5rem, 5vw, 5rem);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-column {
    display: flex;
    flex-direction: column;
}

.footer-heading {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: white;
}

.footer-links {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-links li {
    margin: 0;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
    display: inline-block;
}

.footer-links a:hover {
    color: white;
    text-decoration: underline;
}

.app-downloads {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.app-btn {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background-color: #000;
    color: white;
    padding: 0.75rem 1.25rem;
    border-radius: 8px;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.3s ease;
    width: fit-content;
}

.app-btn:hover {
    background-color: #333;
    color: white;
    text-decoration: none;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.app-btn i {
    font-size: 1.25rem;
}

.footer-divider {
    height: 1px;
    background-color: rgba(255, 255, 255, 0.2);
    margin: 2rem 0;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
}

.copyright {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.9);
    margin: 0;
}

.social-media {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.social-icon {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    text-decoration: none;
    font-size: 1.1rem;
    transition: all 0.3s ease;
}

.social-icon:hover {
    background-color: rgba(255, 255, 255, 0.2);
    color: white;
    text-decoration: none;
    transform: translateY(-2px);
}

/* Responsive Footer */
@media (max-width: 1199px) {
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
        gap: 2.5rem;
    }
}

@media (max-width: 767px) {
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 1.5rem;
        text-align: center;
    }
    
    .app-downloads {
        width: 100%;
    }
    
    .app-btn {
        width: 100%;
        justify-content: center;
    }
}

/* Small Mobile (480px and below) */
@media (max-width: 480px) {
    .header {
        padding: 0.5rem 0.75rem;
    }
    
    .logo-class img {
        width: 80px;
    }
    
    .mobile-menu-toggle {
        width: 40px;
        height: 40px;
    }
    
    .hamburger-line {
        width: 20px;
        height: 2px;
    }
    
    .hero-section {
        max-height: 65dvh;
        min-height: 320px;
    }
    
    .hero-content {
        padding: 1rem 0.75rem;
        gap: 1rem;
    }
    
    .hero-robot {
        min-height: 180px;
        max-height: 220px;
    }
    
    .robot-image {
        max-width: 200px;
    }
    
    .btn-signup,
    .btn-create-course {
        padding: 0.75rem 1.25rem;
        font-size: 0.9rem;
    }
    
    .search-input {
        padding: 0.875rem 1rem;
        font-size: 0.9rem;
    }
    
    .search-btn {
        padding: 0.875rem 1.5rem;
        font-size: 0.9rem;
    }
    
    .course-card-external {
        max-width: min(280px, 90vw);
    }
    
    .course-card-content {
        padding: 1rem;
    }
    
    .course-card-title {
        font-size: 1rem;
    }
    
    .btn-get-started {
        padding: 0.625rem 1rem;
        font-size: 0.875rem;
    }
    
    .footer-heading {
        font-size: 1rem;
    }
    
    .footer-links a {
        font-size: 0.85rem;
    }
    
    .copyright {
        font-size: 0.8rem;
    }
    
    .social-icon {
        width: 36px;
        height: 36px;
        font-size: 1rem;
    }
}

/* Extra Small Mobile (360px and below) */
@media (max-width: 360px) {
    .header {
        padding: 0.5rem;
    }
    
    .logo-class img {
        width: 70px;
    }
    
    .hero-content {
        padding: 0.75rem 0.5rem;
    }
    
    .course-card-external {
        max-width: min(260px, 95vw);
    }
    
    .course-card-content {
        padding: 0.875rem;
    }
}

/* Landscape orientation for mobile */
@media (max-height: 500px) and (orientation: landscape) {
    .hero-section {
        min-height: auto;
        padding: 1rem 0;
    }
    
    .hero-content {
        flex-direction: row;
        min-height: auto;
        padding: 1rem 2rem;
    }
    
    .hero-text {
        text-align: left;
    }
    
    .hero-buttons {
        flex-direction: row;
        justify-content: flex-start;
    }
    
    .btn-signup,
    .btn-create-course {
        width: auto;
    }
    
    .hero-robot {
        min-height: 150px;
        max-height: 200px;
    }
    
    .robot-image {
        max-width: 180px;
    }
}

/* Print styles */
@media print {
    .header,
    .footer,
    .mobile-menu-toggle,
    .hero-robot {
        display: none;
    }
    
    .hero-section {
        min-height: auto;
        background: none;
    }
    
    .hero-section::before,
    .hero-section::after {
        display: none;
    }
    
    .hero-text {
        color: black;
    }
    
    .hero-title,
    .hero-description {
        color: black;
    }
}