:root {
    /* Colors */
    --primary-color: #1aa397;
    /* Teal */
    --primary-hover: #13887d;
    --dark-bg: #111827;
    /* Dark navy for bottom CTA */
    --text-main: #1f2937;
    /* Dark grey for headings */
    --text-body: #6b7280;
    /* Lighter grey for body text */
    --bg-color: #ffffff;
    --bg-secondary: #f9fafb;
    /* Light grey for sections */
    --input-bg: #f3f4f6;
    --white: #ffffff;
    --badge-bg: #fff7ed;
    --badge-text: #c2410c;

    /* Typography */
    --font-family: 'Inter', system-ui, -apple-system, sans-serif;
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;

    /* Spacing */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-12: 3rem;

    /* Borders */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-full: 9999px;

    /* Variables for feature colors */
    --feature-icon-bg-streak: #fff7ed;
    --feature-icon-text-streak: #ea580c;
    --feature-icon-bg-correct: #ecfdf5;
    --feature-icon-text-correct: #059669;
    --feature-icon-bg-exam: #eff6ff;
    --feature-icon-text-exam: #2563eb;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}


/* ALerts */

.alert {
    padding: 15px;
    margin-bottom: 20px;
    border: 1px solid transparent;
    border-radius: 4px;
    font-weight: bold;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border-color: #c3e6cb;
}

.alert-danger {
    background-color: #f8d7da;
    color: #721c24;
    border-color: #f5c6cb;
}

.alert-info {
    background-color: #d1ecf1;
    color: #0c5460;
    border-color: #bee5eb;
}

/* Utilities */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-4);
}

.text-center {
    text-align: center;
}

.flex {
    display: flex;
}

.items-center {
    align-items: center;
}

.justify-between {
    justify-content: space-between;
}

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

.flex-col {
    flex-direction: column;
}

.gap-2 {
    gap: var(--spacing-2);
}

.gap-4 {
    gap: var(--spacing-4);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
}

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.btn-full {
    width: 100%;
}

/* Header */
header {
    padding: var(--spacing-4) 0;
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--bg-secondary);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-4);
}

.logo {
    font-weight: 700;
    font-size: var(--text-lg);
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
}

.logo span {
    color: var(--text-main);
}

.nav-links li a {
    font-weight: 600;
    font-size: var(--text-sm);
    color: var(--text-main);
}

/* Hero Section */
.hero {
    text-align: center;
    padding: var(--spacing-8) var(--spacing-4);
    max-width: 800px;
    margin: 0 auto;
}

.badge {
    display: inline-block;
    background-color: var(--badge-bg);
    color: var(--badge-text);
    padding: var(--spacing-1) var(--spacing-3);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 700;
    margin-bottom: var(--spacing-4);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-main);
    line-height: 1.1;
    margin-bottom: var(--spacing-4);
}

.hero h1 span {
    color: var(--primary-color);
    display: block;
}

.hero p {
    color: var(--text-body);
    font-size: var(--text-base);
    margin-bottom: var(--spacing-6);
}

/* Hero Button Reset */
.hero .btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
}

.hero .btn-primary:hover {
    background-color: var(--primary-hover);
}

.hero-image-container {
    margin-top: var(--spacing-8);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
}

.hero-image-container img {
    width: 100%;
    height: auto;
    display: block;
}

/* Stats Section */
/* Stats Section */
.stats {
    background-color: var(--bg-secondary);
    padding: var(--spacing-8) var(--spacing-4);
    margin-top: var(--spacing-8);
    margin-bottom: var(--spacing-8);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-4);
    max-width: 1200px;
    margin: 0 auto;
}

.stat-item {
    text-align: center;
}

.stat-num {
    display: block;
    font-size: var(--text-2xl);
    font-weight: 800;
    color: var(--text-main);
}

.stat-label {
    font-size: var(--text-sm);
    color: var(--text-body);
}

/* Features Section */
.features-section {
    padding: var(--spacing-8) var(--spacing-4);
}

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-8);
}

.section-title h2 {
    font-size: var(--text-2xl);
    font-weight: 800;
    margin-bottom: var(--spacing-2);
}

.section-title p {
    color: var(--text-body);
}

.feature-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-4);
}

.feature-card {
    background: var(--white);
    padding: var(--spacing-6);
    border-radius: var(--radius-lg);
    border: 1px solid #e5e7eb;
    /* subtle shadow */
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
}

.feature-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-4);
}

.feature-icon svg {
    width: 24px;
    height: 24px;
}

/* Specific icon colors */
.icon-streak {
    background-color: var(--feature-icon-bg-streak);
    color: var(--feature-icon-text-streak);
}

.icon-correct {
    background-color: var(--feature-icon-bg-correct);
    color: var(--feature-icon-text-correct);
}

.icon-exam {
    background-color: var(--feature-icon-bg-exam);
    color: var(--feature-icon-text-exam);
}

.feature-card h3 {
    font-size: var(--text-lg);
    font-weight: 700;
    margin-bottom: var(--spacing-2);
}

.feature-card p {
    color: var(--text-body);
    font-size: var(--text-sm);
    line-height: 1.6;
}

/* Call to Action Bottom */
.cta-bottom {
    background-color: var(--dark-bg);
    color: var(--white);
    padding: var(--spacing-12) var(--spacing-4);
    text-align: center;
    border-radius: var(--radius-lg);
    margin: var(--spacing-12) 0;
}

.cta-icon {
    display: inline-flex;
    background: rgba(255, 255, 255, 0.1);
    padding: var(--spacing-4);
    border-radius: 50%;
    margin-bottom: var(--spacing-4);
}

.cta-bottom h2 {
    font-size: var(--text-2xl);
    margin-bottom: var(--spacing-6);
}

/* Footer */
footer {
    padding: var(--spacing-8) 0;
    text-align: center;
    color: var(--text-body);
    font-size: var(--text-sm);
    border-top: 1px solid #e5e7eb;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: var(--spacing-6);
    margin-bottom: var(--spacing-4);
}

.footer-links a:hover {
    color: var(--primary-color);
}

/* Responsive adjustments */
@media (min-width: 768px) {
    .feature-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .hero {
        padding: var(--spacing-12) var(--spacing-4);
    }

    .hero h1 {
        font-size: 3rem;
    }
}

@media (max-width: 640px) {
    .stats-grid {
        gap: var(--spacing-2);
        grid-template-columns: repeat(3, 1fr);
    }

    .stat-num {
        font-size: var(--text-xl);
    }
}

/* Authentication Page Styles */
.auth-wrapper {
    min-height: 80vh;
    /* Centered visually in viewport */
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-8) var(--spacing-4);
}

.auth-card {
    width: 100%;
    max-width: 400px;
    background: var(--white);
    /* In a full app, might want a card shadow or border, but design looks clean/flat or minimal */
    /* If the design image implies a modal or card: */
    /* border: 1px solid #e5e7eb; */
    /* box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1); */
    /* border-radius: var(--radius-lg); */
    /* padding: var(--spacing-8); */
    /* But image looks like a clean centered column. Let's keep it simple. */
}

.auth-header {
    text-align: center;
    margin-bottom: var(--spacing-8);
}

.auth-header .logo {
    justify-content: center;
    margin-bottom: var(--spacing-6);
    font-size: var(--text-xl);
    /* Larger logo */
}

.auth-header h1 {
    font-size: var(--text-2xl);
    font-weight: 800;
    color: var(--dark-bg);
    /* Dark navy text like image */
    margin-bottom: var(--spacing-2);
}

.auth-header p {
    color: var(--text-body);
    font-size: var(--text-sm);
}

.auth-tabs {
    background-color: var(--bg-secondary);
    padding: var(--spacing-1);
    border-radius: var(--radius-md);
    display: flex;
    margin-bottom: var(--spacing-6);
}

.auth-tab {
    flex: 1;
    text-align: center;
    padding: var(--spacing-2) var(--spacing-4);
    border-radius: var(--radius-sm);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--text-body);
    transition: all 0.2s;
    display: block;
    /* Ensure it behaves like a block for the anchor */
}

.auth-tab.active {
    background-color: var(--white);
    color: var(--text-main);
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.form-group {
    margin-bottom: var(--spacing-4);
}

.form-label {
    display: block;
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: var(--spacing-2);
}

.input-group {
    position: relative;
}

.input-icon {
    position: absolute;
    left: var(--spacing-3);
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-body);
    display: flex;
    /* Fix alignment */
}

.input-icon svg {
    width: 20px;
    height: 20px;
}

.form-input {
    width: 100%;
    padding: 0.75rem var(--spacing-3) 0.75rem 2.75rem;
    /* Left padding for icon */
    border: 1px solid #e5e7eb;
    border-radius: var(--radius-md);
    font-size: var(--text-base);
    color: var(--text-main);
    transition: border-color 0.2s;
}

.form-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(26, 163, 151, 0.1);
}

.password-toggle {
    position: absolute;
    right: var(--spacing-3);
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-body);
    cursor: pointer;
    background: none;
    border: none;
    padding: 0;
}

.forgot-password {
    display: block;
    text-align: center;
    font-size: var(--text-sm);
    color: var(--primary-color);
    font-weight: 600;
    margin-top: var(--spacing-4);
}

.auth-divider {
    display: flex;
    align-items: center;
    margin: var(--spacing-6) 0;
    color: var(--text-body);
    font-size: var(--text-xs);
}

.auth-divider::before,
.auth-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background-color: #e5e7eb;
}

.auth-divider span {
    padding: 0 var(--spacing-4);
}

.social-btn {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: 0.75rem;
    background-color: var(--white);
    border: 1px solid #e5e7eb;
    border-radius: var(--radius-full);
    /* Rounded pill style for social */
    color: var(--text-main);
    font-weight: 600;
    font-size: var(--text-sm);
    transition: background-color 0.2s;
    cursor: pointer;
}

.social-btn:hover {
    background-color: var(--bg-secondary);
}

/*Login*/

.tab-container {
    display: flex;
    background: #f1f5f9;
    /* Light grey background */
    padding: 5px;
    border-radius: 8px;
    margin-bottom: 25px;
}

.tab-btn {
    flex: 1;
    padding: 10px;
    border: none;
    background: transparent;
    cursor: pointer;
    font-weight: 600;
    color: #64748b;
    border-radius: 6px;
    transition: all 0.3s ease;
}

.tab-btn.active {
    background: white;
    color: #0f172a;
    /* Dark text */
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* Toast Notification */
.toast-notification {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    min-width: 300px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }

    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.toast-fade-out {
    animation: fadeOut 0.5s ease-in forwards;
}

@keyframes fadeOut {
    from {
        opacity: 1;
    }

    to {
        opacity: 0;
    }
}