/* ===== CSS VARIABLES ===== */
:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --accent-color: #06b6d4;
    --dark-color: #1e293b;
    --light-color: #f8fafc;
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-accent: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --section-padding: 6rem 0;
    --section-padding-mobile: 4rem 0;
    --container-padding: 0 1rem;
}

/* ===== RESET & BASE STYLES ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Poppins', sans-serif;
    line-height: 1.7;
    color: var(--dark-color);
    overflow-x: hidden;
    font-weight: 400;
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 1rem;
}

h1 { font-weight: 800; }
h2 { font-weight: 700; }
h3 { font-weight: 600; }
h4 { font-weight: 600; }
h5 { font-weight: 500; }
h6 { font-weight: 500; }

p {
    font-family: 'Poppins', sans-serif;
    font-weight: 400;
    line-height: 1.7;
    margin-bottom: 1rem;
}

/* ===== CONTAINER & SECTION SPACING ===== */
.container {
    padding: var(--container-padding);
}

section {
    padding: var(--section-padding);
}

@media (max-width: 768px) {
    section {
        padding: var(--section-padding-mobile);
    }
}

/* ===== LOADING SPLASH SCREEN ===== */
.loading-splash {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    opacity: 1;
    transition: opacity 0.3s ease;
}

.loading-splash.fade-out {
    opacity: 0;
}

.splash-content {
    text-align: center;
    color: white;
    max-width: 500px;
    padding: 2rem;
}

.logo-container {
    margin-bottom: 2rem;
}

.splash-logo {
    width: 80px;
    height: 80px;
    margin-bottom: 1rem;
}

.splash-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin: 0;
}

.progress-container {
    margin-bottom: 2rem;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 1rem;
}

.progress-fill {
    height: 100%;
    background: white;
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    font-size: 1.2rem;
    font-weight: 600;
}

.steps-container {
    display: flex;
    justify-content: space-between;
    margin-bottom: 2rem;
    gap: 1rem;
}

.step-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    opacity: 0.5;
    transition: all 0.3s ease;
}

.step-item.active {
    opacity: 1;
    transform: scale(1.1);
}

.step-item.completed {
    opacity: 1;
    color: #4ade80;
}

.step-item i {
    font-size: 1.5rem;
}

.step-item span {
    font-size: 0.8rem;
    text-align: center;
}

.fact-item {
    font-style: italic;
    opacity: 0.8;
}

.fact-item span {
    transition: opacity 0.3s ease;
}

/* ===== NAVBAR ===== */
.navbar {
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding: 1rem 0;
    transition: all 0.3s ease;
    z-index: 1030;
}

.navbar-brand {
    font-weight: 800;
    font-size: 1.75rem;
    color: var(--primary-color) !important;
    font-family: 'Poppins', sans-serif;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

.brand-logo {
    height: 40px;
}

.nav-link {
    font-weight: 500;
    color: var(--dark-color) !important;
    transition: all 0.3s ease;
    position: relative;
    font-family: 'Poppins', sans-serif;
    padding: 0.5rem 1rem !important;
    margin: 0 0.25rem;
}

.nav-link:hover {
    color: var(--primary-color) !important;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 0;
    left: 50%;
    background: var(--gradient-primary);
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

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

/* ===== BUTTONS ===== */
.btn {
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    border-radius: 50px;
    padding: 12px 30px;
    transition: all 0.3s ease;
    text-transform: none;
    letter-spacing: 0.5px;
}

.btn-primary {
    background: var(--gradient-primary);
    border: none;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
    background: var(--gradient-secondary);
    border: none;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(139, 92, 246, 0.4);
}

/* ===== FOOTER ===== */
.footer {
    background: var(--dark-color);
    color: white;
    padding: 4rem 0 2rem;
    margin-top: 4rem;
    position: relative;
    z-index: 10;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.footer-brand img {
    height: 40px;
    filter: brightness(0) invert(1);
}

.footer-brand span {
    font-weight: 800;
    font-size: 1.5rem;
    color: white;
}

.footer h5 {
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    font-weight: 600;
    font-family: 'Poppins', sans-serif;
}

.footer p {
    color: rgba(255, 255, 255, 0.8);
    font-family: 'Poppins', sans-serif;
    font-weight: 400;
    line-height: 1.7;
}

.footer ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer ul li {
    margin-bottom: 0.75rem;
}

.footer ul li:last-child {
    margin-bottom: 0;
}

.footer ul li a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: all 0.3s ease;
    font-family: 'Poppins', sans-serif;
    font-weight: 400;
    line-height: 1.5;
    display: inline-block;
    position: relative;
}

.footer ul li a:hover {
    color: white;
    transform: translateX(5px);
}

.footer ul li a::before {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -2px;
    left: 0;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.footer ul li a:hover::before {
    width: 100%;
}

.footer hr {
    border-color: rgba(255, 255, 255, 0.2);
    margin: 2rem 0;
    opacity: 0.3;
}

.footer .copyright {
    color: rgba(255, 255, 255, 0.8);
    margin: 0;
    font-family: 'Poppins', sans-serif;
    font-weight: 400;
}

.footer .social-links {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    align-items: center;
}

.footer .social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border-radius: 50%;
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 1.1rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.footer .social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(99, 102, 241, 0.3);
    border-color: var(--primary-color);
}

/* Footer responsive design */
@media (max-width: 768px) {
    .footer {
        padding: 3rem 0 1.5rem;
        margin-top: 2rem;
    }
    
    .footer h5 {
        margin-bottom: 1rem;
        font-size: 1.1rem;
    }
    
    .footer ul li {
        margin-bottom: 0.5rem;
    }
    
    .footer .social-links {
        justify-content: center;
        margin-top: 1rem;
    }
    
    .footer .copyright {
        text-align: center;
        margin-bottom: 1rem;
    }
}

@media (max-width: 576px) {
    .footer {
        padding: 2rem 0 1rem;
    }
    
    .footer-brand {
        margin-bottom: 1rem;
    }
    
    .footer-brand span {
        font-size: 1.25rem;
    }
    
    .footer h5 {
        font-size: 1rem;
        margin-bottom: 0.75rem;
    }
    
    .footer ul li a {
        font-size: 0.9rem;
    }
    
    .footer .social-links a {
        width: 35px;
        height: 35px;
        font-size: 1rem;
    }
}

/* ===== DOUBT RESULTS PAGE SPECIFIC STYLES ===== */
.question-card {
    background: var(--gradient-primary);
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    overflow: hidden;
    color: white;
    padding: 2rem;
    margin-bottom: 3rem;
}

.video-carousel {
    background: #f8f9fa;
    border-radius: 15px;
    padding: 2rem;
    margin: 2rem 0;
}

.video-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    height: 400px;
    cursor: pointer;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
}

.video-thumbnail {
    height: 200px;
    background-size: cover;
    background-position: center;
    position: relative;
}

.play-button {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(255,255,255,0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: #dc3545;
    transition: all 0.3s ease;
}

.video-card:hover .play-button {
    background: #dc3545;
    color: white;
    transform: translate(-50%, -50%) scale(1.1);
}

.ai-explanation {
    background: var(--gradient-primary);
    border-radius: 20px;
    color: white;
    padding: 2rem;
    margin: 2rem 0;
}

.comments-section {
    background: white;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    padding: 2rem;
    margin: 2rem 0;
}

.comment-card {
    border: 1px solid #e9ecef;
    border-radius: 15px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: box-shadow 0.3s ease;
}

.comment-card:hover {
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.like-dislike-buttons {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.btn-like, .btn-dislike {
    border: none;
    background: #f8f9fa;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    transition: all 0.3s ease;
}

.btn-like:hover, .btn-dislike:hover {
    background: #e9ecef;
}

.btn-like.active {
    background: #28a745;
    color: white;
}

.btn-dislike.active {
    background: #dc3545;
    color: white;
}

.modal-video {
    width: 100%;
    height: 400px;
    border-radius: 10px;
}

.image-gallery {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-top: 1rem;
}

.question-image {
    width: 120px;
    height: 120px;
    object-fit: cover;
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.question-image:hover {
    transform: scale(1.05);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: #2d3748;
}

.download-btn {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
    border: none;
    border-radius: 25px;
    padding: 0.75rem 1.5rem;
    color: white;
    font-weight: 600;
    transition: all 0.3s ease;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(40, 167, 69, 0.3);
}

/* ===== PROMOTIONAL COURSES SECTION ===== */
.courses-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 20px;
    padding: 2rem;
    margin: 2rem 0;
    color: white;
}

.course-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
    height: 100%;
}

.course-card:hover {
    transform: translateY(-5px);
}

.course-image {
    height: 200px;
    background-size: cover;
    background-position: center;
    position: relative;
}

.course-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: #dc3545;
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.course-content {
    padding: 1.5rem;
}

.course-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--dark-color);
}

.course-instructor {
    color: #6c757d;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.course-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* ===== REPLY SYSTEM ===== */
.reply-section {
    margin-left: 3rem;
    margin-top: 1rem;
    padding-left: 1rem;
    border-left: 3px solid #e9ecef;
}

.reply-form {
    margin-top: 1rem;
    display: none;
}

.reply-form.active {
    display: block;
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
    .navbar-brand {
        font-size: 1.5rem;
    }
    
    .brand-logo {
        height: 30px;
    }
    
    .splash-title {
        font-size: 2rem;
    }
    
    .steps-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .video-card {
        height: 350px;
    }
    
    .reply-section {
        margin-left: 1rem;
    }
    
    .social-links {
        justify-content: center;
    }
}

@media (max-width: 576px) {
    .question-card {
        padding: 1.5rem;
    }
    
    .video-carousel {
        padding: 1rem;
    }
    
    .comments-section {
        padding: 1.5rem;
    }
    
    .image-gallery {
        justify-content: center;
    }
}