:root {
    --card-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    --avatar-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --color-primary: #4f46e5; 
    --color-text-dark: #1f2937;
    --color-text-medium: #374151;
    --color-text-light: #6b7280;
    --color-bg-light: #f3f4f6;
    --color-error: #ef4444;
    --color-success: #065f46;
}
*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column; 
    justify-content: center;
    align-items: center;
    padding: 1rem;
    background-color: #f0f4f8;
    background-image: 
        radial-gradient(at 0% 0%, hsla(204, 70%, 85%, 0.3) 0px, transparent 50%),
        radial-gradient(at 98% 1%, hsla(240, 60%, 85%, 0.3) 0px, transparent 50%);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}


.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}


a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible {
    outline: 2px solid #3b82f6;
    outline-offset: 2px;
    border-radius: 0.375rem;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
    display: none; 
}

.nav {
    background-color: #ffb300;
    padding: 1.2rem 1rem;
    width: 100%;
    position: fixed; 
    top: 0;
    left: 0;
    z-index: 10;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}

.nav a {
    color: var(--color-text-dark);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 0.75rem;
    border-radius: 20px;
    transition: background-color 0.2s, color 0.2s;
}

.nav a:hover {
    color: white;
    font-size: 1.2rem;
}

.nav a.active{
    background-color: #ffce64;
}

.page-container {
    padding: 5rem 1rem 2rem 1rem;
    width: 100%;
    max-width: 64rem;
    margin: 0 auto;
    animation: fadeIn 0.8s ease-out forwards;
}

.page-title {
    color: #000;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 2rem;
    text-align: center;
}

body > article.profile-card {
    margin-top: 5rem; 
    margin-bottom: 1rem;
}

.profile-card {
    background-color: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    box-shadow: var(--card-shadow);
    border-radius: 1rem;
    width: 100%;
    max-width: 64rem;
    overflow: hidden;
    animation: fadeIn 0.8s ease-out forwards;
}

.card-body {
    display: flex;
    flex-direction: column;
}

.card-avatar-section {
    background-color: rgba(243, 244, 246, 0.5);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.card-avatar {
    border-radius: 50%;
    height: 10rem;
    width: 10rem;
    object-fit: cover;
    box-shadow: var(--avatar-shadow);
    border: 4px solid white;
}

.card-info-section {
    padding: 2rem;
}

header {
    margin-bottom: 1.5rem;
}

h2[data-testid="test-user-name"] {
    font-size: 2.25rem;
    line-height: 2.5rem;
    font-weight: 700;
    color: var(--color-text-dark);
    margin: 0;
}

p[data-testid="test-user-bio"] {
    margin-top: 0.5rem;
    color: var(--color-text-light);
}

.time-section {
    margin-bottom: 1.5rem;
}

.time-section p {
    font-size: 0.875rem;
    color: var(--color-text-light);
    margin: 0 0 0.25rem 0;
}

div[data-testid="test-user-time"] {
    font-size: 1.125rem;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
    background-color: var(--color-bg-light);
    padding: 0.5rem;
    border-radius: 0.5rem;
    color: var(--color-primary);
    text-align: center;
}

.social-links h3, .lists-container h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text-medium);
    margin-bottom: 0.5rem;
}

ul[data-testid="test-user-social-links"] {
    display: flex;
    gap: 1rem;
    list-style: none;
    padding: 0;
    margin: 0 0 1.5rem 0;
}

ul[data-testid="test-user-social-links"] a {
    display: block;
    padding: 0.25rem;
    color: var(--color-text-light);
    transition: color 0.3s ease;
}

ul[data-testid="test-user-social-links"] a:hover {
    color: var(--color-text-dark);
}

[data-testid="test-user-social-twitter"]:hover {
    color: #1DA1F2; 
}

ul[data-testid="test-user-social-links"] svg {
    width: 1.5rem;
    height: 1.5rem;
}

.lists-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

.lists-container ul {
    list-style-position: inside;
    color: var(--color-text-medium);
    padding-left: 0;
    margin: 0;
}

.lists-container li {
    margin-bottom: 0.25rem;
}

.form-card {
    background-color: white;
    box-shadow: var(--card-shadow);
    border-radius: 1rem;
    padding: 2rem;
    max-width: 40rem;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-weight: 500;
    color: var(--color-text-medium);
    margin-bottom: 0.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #d1d5db;
    border-radius: 0.5rem;
    font-family: inherit;
    font-size: 1rem;
    color: var(--color-text-dark);
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: #ffb300;
    outline: none;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

.form-group input[aria-invalid="true"],
.form-group textarea[aria-invalid="true"] {
    border-color: var(--color-error);
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.2);
}

.error-message {
    color: var(--color-error);
    font-size: 0.875rem;
    margin-top: 0.25rem;
    height: 1.25rem; /* Reserve space for error text */
}

.submit-button {
    display: block;
    width: 100%;
    padding: 0.75rem;
    background-color: black;
    color: white;
    font-weight: 600;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background-color 0.2s;
}

.submit-button:hover {
    background-color: #404040;
}

.success-message {
    background-color: #d1fae5;
    color: var(--color-success);
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
    font-weight: 600;
}


.about-content {
    background-color: white;
    box-shadow: var(--card-shadow);
    border-radius: 1rem;
    padding: 2rem;
    max-width: 64rem;
    margin: 0 auto;
}

.about-content section {
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--color-bg-light);
}

.about-content section:last-of-type {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.about-content h2 {
    color: #2e2d2d;
    font-size: 1.5rem;
    font-weight: 700;
    margin-top: 0;
    margin-bottom: 0.75rem;
}

.about-content p, .about-content ul {
    color: var(--color-text-medium);
    line-height: 1.6;
}

.about-content ul {
    list-style: disc;
    padding-left: 1.5rem;
}



@media (max-width: 767px) {
   
    .card-info-section {
        text-align: center;
    }

    ul[data-testid="test-user-social-links"] {
        justify-content: center;
    }

    .lists-container ul {
        text-align: left;
    }

}

@media (min-width: 768px) {
    .card-body {
        flex-direction: row;
    }
    .card-avatar-section {
        width: 33.333333%;
    }
    .card-info-section {
        width: 66.666667%;
    }
}

@media (min-width: 640px) {
    .lists-container {
        grid-template-columns: repeat(2, 1fr);
    }

}