/* Glassmorphism Design System for IELTS Practice Portal */
:root {
    --glass-bg: rgba(255, 255, 255, 0.55);
    --glass-bg-hover: rgba(255, 255, 255, 0.75);
    --glass-border: rgba(255, 255, 255, 0.7);
    --glass-shadow: 0 8px 32px 0 rgba(30, 58, 138, 0.12);
    --blur-intensity: blur(14px);
    
    --primary-blue: #2563eb;
    --accent-sky: #0ea5e9;
    --emerald-green: #10b981;
    --amber-gold: #f59e0b;
    --purple-indigo: #6366f1;
}

body {
    background-color: #f1f5f9;
    background-image: 
        radial-gradient(at 20% 10%, hsla(217, 91%, 91%, 1) 0px, transparent 50%),
        radial-gradient(at 80% 0%, hsla(199, 89%, 89%, 1) 0px, transparent 50%),
        radial-gradient(at 0% 50%, hsla(210, 100%, 96%, 1) 0px, transparent 50%),
        radial-gradient(at 80% 50%, hsla(160, 84%, 91%, 1) 0px, transparent 50%),
        radial-gradient(at 0% 100%, hsla(220, 90%, 93%, 1) 0px, transparent 50%),
        radial-gradient(at 80% 100%, hsla(240, 85%, 92%, 1) 0px, transparent 50%);
    background-attachment: fixed;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    color: #0f172a;
    min-height: 100vh;
    margin: 0;
}

/* Glass Card Component */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: var(--blur-intensity);
    -webkit-backdrop-filter: var(--blur-intensity);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    box-shadow: var(--glass-shadow);
    padding: 2rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.glass-card:hover {
    background: var(--glass-bg-hover);
    transform: translateY(-4px);
    box-shadow: 0 16px 40px 0 rgba(30, 58, 138, 0.18);
}

/* Hero Section */
.glass-hero {
    text-align: center;
    margin-bottom: 2.5rem;
    color: #0f172a;
    background: linear-gradient(135deg, rgba(255,255,255,0.8), rgba(255,255,255,0.4));
    border: 1px solid rgba(255,255,255,0.9);
}

.glass-hero h1 {
    font-size: 2.75rem;
    font-weight: 900;
    margin-bottom: 0.75rem;
    background: linear-gradient(135deg, #1e3a8a, #2563eb, #0284c7);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}

.glass-hero p {
    font-size: 1.15rem;
    max-width: 820px;
    margin: 0 auto 1.5rem;
    color: #334155;
    font-weight: 500;
    line-height: 1.6;
}

/* Progress Bar */
.glass-progress-container {
    background: rgba(255, 255, 255, 0.7);
    border: 1px solid rgba(255, 255, 255, 0.9);
    border-radius: 99px;
    height: 14px;
    width: 100%;
    max-width: 480px;
    margin: 0 auto;
    overflow: hidden;
    position: relative;
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.06);
}

.glass-progress-fill {
    background: linear-gradient(90deg, #2563eb, #10b981);
    height: 100%;
    width: 0%;
    transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
    border-radius: 99px;
}

/* Toggle Switch pill */
.mode-toggle-container {
    display: inline-flex;
    background: rgba(15, 23, 42, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.8);
    padding: 4px;
    border-radius: 99px;
    gap: 4px;
    margin: 1rem 0;
}

.mode-toggle-btn {
    padding: 0.6rem 1.4rem;
    border-radius: 99px;
    border: none;
    background: transparent;
    font-weight: 700;
    font-size: 0.95rem;
    color: #64748b;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.mode-toggle-btn.active {
    background: #ffffff;
    color: #1e3a8a;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15);
}

/* Grid Layouts */
.modules-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.band-tiers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.5rem;
}

/* Module Cards */
.module-card {
    display: flex;
    flex-direction: column;
    height: 100%;
    justify-content: space-between;
}

.module-icon-box {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 1.25rem;
    box-shadow: 0 8px 16px rgba(0,0,0,0.06);
}

/* Buttons */
.btn-glass {
    background: rgba(37, 99, 235, 0.1);
    border: 1px solid rgba(37, 99, 235, 0.25);
    color: #1d4ed8;
    padding: 0.75rem 1.5rem;
    border-radius: 12px;
    font-weight: 700;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.btn-glass:hover {
    background: #2563eb;
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.3);
}

.btn-glass-primary {
    background: linear-gradient(135deg, #2563eb, #1d4ed8);
    border: none;
    color: #ffffff;
    padding: 0.75rem 1.5rem;
    border-radius: 12px;
    font-weight: 700;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}

.btn-glass-primary:hover {
    background: linear-gradient(135deg, #1d4ed8, #1e40af);
    transform: translateY(-2px);
    box-shadow: 0 8px 22px rgba(37, 99, 235, 0.45);
    color: #ffffff;
}

/* Badges */
.badge-glass {
    padding: 0.35rem 0.85rem;
    border-radius: 99px;
    font-size: 0.8rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.badge-blue { background: rgba(37, 99, 235, 0.12); color: #1d4ed8; border: 1px solid rgba(37, 99, 235, 0.3); }
.badge-green { background: rgba(16, 185, 129, 0.12); color: #047857; border: 1px solid rgba(16, 185, 129, 0.3); }
.badge-amber { background: rgba(245, 158, 11, 0.12); color: #b45309; border: 1px solid rgba(245, 158, 11, 0.3); }
.badge-purple { background: rgba(139, 92, 246, 0.12); color: #6d28d9; border: 1px solid rgba(139, 92, 246, 0.3); }

/* Calculator styling */
.calculator-input {
    width: 100%;
    padding: 0.65rem 1rem;
    border-radius: 10px;
    border: 1px solid rgba(203, 213, 225, 0.8);
    background: rgba(255, 255, 255, 0.9);
    font-size: 1rem;
    font-weight: 700;
    color: #1e293b;
    outline: none;
    transition: all 0.2s ease;
}

.calculator-input:focus {
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.animate-fade-in {
    animation: fadeIn 0.4s ease forwards;
}

/* Mobile Responsive Navbar & Drawer */
.mobile-nav-toggle {
    display: none;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    font-size: 1.5rem;
    color: #0f172a;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-drawer {
    display: none;
    flex-direction: column;
    gap: 0.5rem;
    padding: 1.25rem 1.5rem;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.8);
    box-shadow: 0 10px 25px rgba(0,0,0,0.08);
}

.mobile-drawer.active {
    display: flex !important;
}

.mobile-drawer a {
    text-decoration: none;
    color: #334155;
    font-weight: 700;
    font-size: 1rem;
    padding: 0.65rem 0.9rem;
    border-radius: 10px;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    transition: all 0.2s ease;
}

.mobile-drawer a:hover,
.mobile-drawer a.active {
    background: rgba(37, 99, 235, 0.1);
    color: #2563eb;
}

@media (max-width: 992px) {
    .nav-links {
        display: none !important;
    }
    .mobile-nav-toggle {
        display: flex !important;
    }
}