@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

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

:root {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --card-bg: rgba(255, 255, 255, 0.05);
    --card-border: rgba(255, 255, 255, 0.1);
    --smoke-effect: rgba(0, 0, 0, 0.3);
}

.light-mode {
    --bg-primary: #f8fafc;
    --bg-secondary: #e2e8f0;
    --bg-tertiary: #cbd5e1;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --card-bg: rgba(255, 255, 255, 0.8);
    --card-border: rgba(0, 0, 0, 0.1);
    --smoke-effect: rgba(255, 255, 255, 0.3);
}

body {
    font-family: 'Inter', sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 50%, var(--bg-tertiary) 100%);
    min-height: 100vh;
    color: var(--text-primary);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    transition: all 0.5s ease;
    position: relative;
    overflow-x: hidden;
    font-size: clamp(16px, 2.5vw, 18px); /* Responsive font size */
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 80%, var(--smoke-effect) 0%, transparent 50%),
                radial-gradient(circle at 80% 20%, var(--smoke-effect) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: clamp(12px, 2vw, 20px); /* Responsive border-radius */
    transition: all 0.4s ease;
    transform-style: preserve-3d;
    perspective: 1000px;
}

.glass-card:hover {
    transform: translateY(-8px) rotateX(5deg) rotateY(-2deg);
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    border-color: rgba(255, 255, 255, 0.2);
}

.course-card {
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    transform-style: preserve-3d;
}

.course-card:hover {
    transform: translateY(-10px) rotateX(8deg) scale(1.02);
}

.btn-primary {
    background: linear-gradient(45deg, var(--accent-primary), var(--accent-secondary));
    border: none;
    border-radius: clamp(10px, 1.5vw, 15px);
    padding: clamp(10px, 1.5vw, 12px) clamp(20px, 2.5vw, 24px);
    color: white;
    font-weight: 600;
    font-size: clamp(14px, 2vw, 16px);
    transition: all 0.3s ease;
    transform: translateZ(20px);
    width: fit-content;
    min-width: clamp(120px, 20vw, 150px); /* Prevent buttons from being too small */
}

.btn-primary:hover {
    transform: translateY(-3px) translateZ(30px);
    box-shadow: 0 15px 35px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid var(--card-border);
    border-radius: clamp(10px, 1.5vw, 15px);
    padding: clamp(10px, 1.5vw, 12px) clamp(20px, 2.5vw, 24px);
    color: var(--text-primary);
    font-weight: 600;
    font-size: clamp(14px, 2vw, 16px);
    transition: all 0.3s ease;
    width: fit-content;
    min-width: clamp(120px, 20vw, 150px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.nav-link {
    position: relative;
    padding: clamp(8px, 1.5vw, 10px) clamp(15px, 2vw, 20px);
    font-size: clamp(14px, 2vw, 16px);
    transition: all 0.3s ease;
    transform-style: preserve-3d;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    width: 0;
    height: 3px;
    background: linear-gradient(45deg, var(--accent-primary), var(--accent-secondary));
    transition: all 0.3s ease;
    transform: translateX(-50%) translateZ(0);
    border-radius: 2px;
}

.nav-link:hover::after {
    width: 80%;
}

.progress-ring {
    transform: rotate(-90deg);
    transition: stroke-dashoffset 0.5s ease;
}

.modal {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-content {
    background: var(--card-bg);
    backdrop-filter: blur(30px);
    border: 1px solid var(--card-border);
    border-radius: clamp(15px, 2vw, 25px);
    padding: clamp(20px, 3vw, 30px);
    width: clamp(280px, 90%, 600px);
    max-height: 90vh;
    overflow-y: auto;
    transform-style: preserve-3d;
    perspective: 1000px;
}

.form-input {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--card-border);
    border-radius: clamp(10px, 1.5vw, 15px);
    padding: clamp(12px, 1.5vw, 15px);
    color: var(--text-primary);
    width: 100%;
    font-size: clamp(14px, 2vw, 16px);
    transition: all 0.3s ease;
}

.form-input:focus {
    border-color: var(--accent-primary);
    background: rgba(255, 255, 255, 0.12);
    outline: none;
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
    transform: translateZ(10px);
}

.footer {
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(20px);
    border-top: 1px solid var(--card-border);
    padding: clamp(20px, 4vw, 40px) clamp(10px, 2vw, 20px);
}

.fade-in {
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from { 
        opacity: 0; 
        transform: translateY(30px) rotateX(15deg);
    }
    to { 
        opacity: 1; 
        transform: translateY(0) rotateX(0);
    }
}

.slide-in {
    animation: slideIn 0.6s ease-out;
}

@keyframes slideIn {
    from { transform: translateX(100%) rotateY(15deg); }
    to { transform: translateX(0) rotateY(0); }
}

.floating {
    animation: floating 3s ease-in-out infinite;
}

@keyframes floating {
    0%, 100% { transform: translateY(0) rotateX(5deg); }
    50% { transform: translateY(-10px) rotateX(-5deg); }
}

.pulse {
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1) rotate(0deg); }
    50% { transform: scale(1.05) rotate(5deg); }
}

.quiz-option {
    background: rgba(255, 255, 255, 0.08);
    border: 2px solid transparent;
    border-radius: clamp(10px, 1.5vw, 15px);
    padding: clamp(15px, 2vw, 20px);
    cursor: pointer;
    transition: all 0.3s ease;
    transform-style: preserve-3d;
    font-size: clamp(14px, 2vw, 16px);
}

.quiz-option:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-3px) rotateX(5deg);
    border-color: var(--accent-primary);
}

.quiz-option.correct {
    border-color: #10b981;
    background: rgba(16, 185, 129, 0.1);
    transform: translateY(-5px) scale(1.02);
}

.quiz-option.incorrect {
    border-color: #ef4444;
    background: rgba(239, 68, 68, 0.1);
}

.course-badge {
    background: linear-gradient(45deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    padding: clamp(5px, 1vw, 6px) clamp(10px, 1.5vw, 12px);
    border-radius: clamp(15px, 2vw, 20px);
    font-size: clamp(10px, 1.5vw, 12px);
    font-weight: 600;
    transform: translateZ(10px);
}

.stats-card {
    transform-style: preserve-3d;
    perspective: 1000px;
}

.stats-card:hover {
    transform: rotateY(5deg) rotateX(5deg);
}

.three-d-text {
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3),
                 4px 4px 8px rgba(0, 0, 0, 0.2),
                 6px 6px 12px rgba(0, 0, 0, 0.1);
}

.theme-toggle {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 25px;
    padding: clamp(8px, 1.5vw, 10px);
    cursor: pointer;
    transition: all 0.5s ease;
    transform-style: preserve-3d;
}

.theme-toggle:hover {
    transform: rotate(180deg) scale(1.1);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.progress-bar-3d {
    background: rgba(255, 255, 255, 0.1);
    border-radius: clamp(8px, 1vw, 10px);
    overflow: hidden;
    height: clamp(10px, 1.5vw, 12px);
    transform: translateZ(5px);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    border-radius: clamp(8px, 1vw, 10px);
    transition: width 0.8s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 0 20px rgba(99, 102, 241, 0.3);
}

.module-card {
    transform: translateZ(0);
    transition: all 0.4s ease;
}

.module-card:hover {
    transform: translateZ(20px) rotateY(5deg);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.certificate {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    border: 3px solid #cbd5e1;
    border-radius: clamp(15px, 2vw, 20px);
    padding: clamp(20px, 3vw, 40px);
    text-align: center;
    transform: perspective(1000px) rotateY(5deg) rotateX(5deg);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.3);
    transition: all 0.5s ease;
}

.certificate:hover {
    transform: perspective(1000px) rotateY(0) rotateX(0) scale(1.02);
}

/* Mobile Menu Styles */
#mobile-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: clamp(250px, 80%, 350px); /* Responsive width */
    height: 100vh;
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    border-left: 1px solid var(--card-border);
    transition: right 0.4s ease-in-out;
    z-index: 999;
    padding: clamp(15px, 3vw, 20px);
    display: flex;
    flex-direction: column;
}

#mobile-menu.open {
    right: 0;
}

.mobile-nav-link {
    display: block;
    padding: clamp(12px, 2vw, 15px);
    text-align: center;
    font-size: clamp(16px, 3vw, 18px);
    color: var(--text-primary);
    transition: all 0.3s ease;
    border-radius: clamp(10px, 1.5vw, 15px);
    margin-bottom: 10px;
    background: rgba(255, 255, 255, 0.05);
}

.mobile-nav-link:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateX(10px);
}

.hamburger {
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    width: clamp(24px, 5vw, 32px);
    height: clamp(24px, 5vw, 32px);
    cursor: pointer;
}

.hamburger span {
    width: 100%;
    height: clamp(3px, 0.5vw, 4px);
    background: var(--text-primary);
    transition: all 0.3s ease;
    border-radius: 2px;
}

.hamburger.open span:nth-child(1) {
    transform: rotate(45deg) translate(clamp(8px, 1.5vw, 10px), clamp(8px, 1.5vw, 10px));
}

.hamburger.open span:nth-child(2) {
    opacity: 0;
}

.hamburger.open span:nth-child(3) {
    transform: rotate(-45deg) translate(clamp(6px, 1vw, 7px), clamp(-7px, -1vw, -8px));
}

.close-mobile-menu {
    position: absolute;
    top: clamp(15px, 2vw, 20px);
    right: clamp(15px, 2vw, 20px);
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 50%;
    width: clamp(32px, 6vw, 40px);
    height: clamp(32px, 6vw, 40px);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.close-mobile-menu:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: rotate(90deg);
}

/* Responsive adjustments */
@media (max-width: 1024px) {
    .container {
        max-width: 100%;
        padding-left: clamp(10px, 2vw, 15px);
        padding-right: clamp(10px, 2vw, 15px);
    }

    .glass-card {
        padding: clamp(12px, 2vw, 16px);
    }

    .course-card img {
        height: clamp(150px, 25vw, 180px);
    }

    .stats-card {
        padding: clamp(12px, 2vw, 16px);
    }

    .modal-content {
        width: clamp(260px, 85%, 500px);
        padding: clamp(15px, 2.5vw, 20px);
    }

    .certificate {
        padding: clamp(15px, 2.5vw, 20px);
    }
}

@media (max-width: 768px) {
    .hidden.md\\:flex {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    #mobile-menu {
        display: flex;
    }

    .course-card img {
        height: clamp(120px, 30vw, 160px);
    }

    .btn-primary, .btn-secondary {
        width: 100%;
        text-align: center;
    }

    .progress-bar-3d {
        width: 100%;
    }

    .stats-card h3 {
        font-size: clamp(16px, 2.5vw, 18px);
    }

    .stats-card p {
        font-size: clamp(20px, 4vw, 24px);
    }

    h1 {
        font-size: clamp(32px, 8vw, 40px);
    }

    h2 {
        font-size: clamp(24px, 6vw, 28px);
    }

    h3 {
        font-size: clamp(18px, 4vw, 20px);
    }

    .footer .grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer .flex {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    body {
        font-size: clamp(14px, 3vw, 16px);
    }

    .glass-card {
        border-radius: 12px;
    }

    .course-card img {
        height: clamp(100px, 35vw, 140px);
    }

    .btn-primary, .btn-secondary {
        padding: clamp(8px, 2vw, 10px) clamp(15px, 3vw, 20px);
        font-size: clamp(12px, 2.5vw, 14px);
    }

    .modal-content {
        width: clamp(240px, 90%, 400px);
        padding: clamp(12px, 2vw, 15px);
    }

    .hamburger {
        width: clamp(20px, 6vw, 28px);
        height: clamp(20px, 6vw, 28px);
    }

    .close-mobile-menu {
        width: clamp(28px, 6vw, 36px);
        height: clamp(28px, 6vw, 36px);
    }

    .mobile-nav-link {
        font-size: clamp(14px, 3.5vw, 16px);
        padding: clamp(10px, 2vw, 12px);
    }

    .certificate {
        padding: clamp(12px, 2vw, 15px);
    }

    .certificate h3 {
        font-size: clamp(18px, 4vw, 20px);
    }

    .certificate h4 {
        font-size: clamp(16px, 3.5vw, 18px);
    }
}