:root {
    --primary-bg: #0d172e;        
    --secondary-bg: #1e293b;      
    --accent-main: #4ade80;       
    --accent-text: #00d0e1;       
    --light-text: #e2e8f0;        
    --muted-text: #94a3b8;        
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
    min-height: 100vh;
    background-color: var(--primary-bg);
    color: var(--light-text);
    line-height: 1.6;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 1rem 1rem;
}

h1 {
    font-size: 2.25rem; 
    font-weight: 800;
    margin-bottom: 2rem;
    text-align: center;
    color: var(--accent-text);
}

.navbar {
    background-color: var(--secondary-bg);
    padding: 1rem 0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    border-bottom: 2px solid var(--accent-text);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative; 
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-text);
}

#menu-toggle-input {
    display: none;
}

.menu-toggle-label { 
    display: none; 
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 20; 
    width: 2rem; 
    height: 2rem; 
    display: flex;
    align-items: center;
    justify-content: center;
}

.hamburger-icon {
    display: block;
    width: 100%;
    height: 3px;
    background-color: var(--accent-main);
    border-radius: 9999px;
    position: relative;
    transition: background-color 0.3s;
}

.hamburger-icon::before,
.hamburger-icon::after {
    content: '';
    display: block;
    width: 100%;
    height: 3px;
    background-color: var(--accent-main);
    border-radius: 9999px;
    position: absolute;
    left: 0;
    transition: transform 0.3s, top 0.3s;
}

.hamburger-icon::before {
    top: -8px;
}

.hamburger-icon::after {
    top: 8px;
}

#menu-toggle-input:checked ~ .menu-toggle-label .hamburger-icon {
    background-color: transparent;
}

#menu-toggle-input:checked ~ .menu-toggle-label .hamburger-icon::before {
    transform: rotate(45deg);
    top: 0;
}

#menu-toggle-input:checked ~ .menu-toggle-label .hamburger-icon::after {
    transform: rotate(-45deg);
    top: 0;
}

.nav-links a {
    color: var(--light-text);
    text-decoration: none;
    padding: 0.5rem 0.75rem;
    border-radius: 0.5rem;
    transition: background-color 0.3s, color 0.3s;
}

.nav-links a:hover {
    background-color: var(--accent-main);
    color: var(--primary-bg);
}

.dark-mode-btn {
    background-color: var(--accent-main);
    color: var(--primary-bg);
    border: none;
    padding: 0.5rem 0.75rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-weight: 600;
    transition: background-color 0.3s, color 0.3s;
}

.dark-mode-btn:hover {
    background-color: var(--accent-text);
}

body.dark-mode {
    --primary-bg: #121212;
    --secondary-bg: #1e1e1e;
    --light-text: #f0f0f0;
    --muted-text: #a0a0a0;
}

.error-message {
    color: #ff6b6b;
    font-size: 0.75rem;
    margin-top: 0.25rem;
}

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

.card {
    background-color: var(--secondary-bg);
    padding: 1.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.2);
    border: 1px solid var(--accent-text);
    transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}

.card:hover {
    transform: scale(1.02);
    border-color: var(--accent-main);
    box-shadow: 0 10px 25px rgba(0, 208, 225, 0.4);
}

.card-image {
    height: 8rem;
    background-color: rgba(0, 208, 225, 0.1);
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    border: 2px solid var(--accent-text);
    color: var(--light-text);
}

.card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--light-text);
    margin-bottom: 0.5rem;
}

.card p {
    color: var(--muted-text);
    font-size: 0.875rem;
    text-align: justify;
}

.card a {
    color: var(--light-text);
    text-decoration: none;
}

.about-content {
    background-color: var(--secondary-bg);
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.2);
    border: 1px solid var(--accent-text);
    display: flex;
    flex-direction: column; 
    align-items: center;
    gap: 2rem;
}

.about-avatar {
    flex-shrink: 0;
    width: 12rem;
    height: 12rem;
    border-radius: 50%;
    background-color: var(--accent-main);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-bg);
    box-shadow: 0 0 0 4px var(--accent-text), 0 0 0 8px var(--primary-bg);
    overflow: hidden; 
}

.profile-photo {
    width: 100%;
    height: 100%;
    object-fit: cover; 
}

.about-description {
    flex-grow: 1;
}

.about-description h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent-text);
    margin-bottom: 1rem;
}

.about-description p {
    color: var(--light-text);
    margin-bottom: 1rem;
    text-align: justify;
}

.tag {
    display: inline-block;
    background-color: rgba(0, 208, 225, 0.3); 
    color: var(--primary-bg); 
    font-size: 0.75rem;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px; 
    font-weight: 600;
    margin-right: 0.5rem;
    margin-bottom: 0.5rem;
}

.form-container {
    max-width: 40rem;
    margin: 0 auto;
    background-color: var(--secondary-bg);
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.2);
    border: 1px solid var(--accent-text);
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--light-text);
}

.form-input, .form-textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    background-color: var(--primary-bg);
    border: 1px solid rgba(0, 208, 225, 0.5); 
    border-radius: 0.5rem;
    color: var(--light-text);
    transition: border-color 0.15s, box-shadow 0.15s;
}

.form-input::placeholder, .form-textarea::placeholder {
    color: var(--muted-text);
}

.form-input:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--accent-text);
    box-shadow: 0 0 0 3px rgba(74, 222, 128, 0.5); 
}

.form-btn {
    width: 100%;
    background-color: var(--accent-main);
    color: var(--primary-bg);
    font-weight: 700;
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    border: none;
    cursor: pointer;
    transition: opacity 0.3s, box-shadow 0.3s;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.form-btn:hover {
    opacity: 0.9;
    box-shadow: 0 6px 10px rgba(74, 222, 128, 0.5);
}

.feedback-message {
    margin-top: 1rem;
    padding: 0.75rem;
    background-color: rgba(0, 208, 225, 0.2);
    color: var(--accent-text);
    border-radius: 0.5rem;
    border: 1px solid var(--accent-text);
    text-align: center;
}

.pesan-error {
    color: #ff6b6b;
    font-size: 0.75rem;
    margin-top: 0.25rem;
}

@media (max-width: 768px) {
    .menu-toggle-label {
        display: flex;
    }

    .nav-links {
        display: none;
        flex-direction: column;
        width: 100%;
        position: absolute;
        top: 100%;
        left: 0;
        background-color: var(--secondary-bg);
        border-top: 1px solid rgba(0, 208, 225, 0.3);
        box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
        z-index: 10;
        padding: 0.5rem 0;
    }

    .dark-mode-btn {
        display: block;
        width: 100%;
        margin: 0.5rem 0;
        text-align: center;
    }

    #menu-toggle-input:checked ~ .nav-links {
        display: flex;
    }

    .nav-links a {
        display: block;
        padding: 0.75rem 1rem;
        border-radius: 0;
        text-align: center;
    }

    .project-grid {
        grid-template-columns: 1fr; 
    }

    .container {
        padding: 1rem 1.5rem;
    }
}

@media (min-width: 481px) and (max-width: 768px) {
    .project-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .container {
        padding: 1rem 1.5rem;
    }
}

@media (min-width: 769px) {
    .menu-toggle-label {
        display: none;
    }

    .nav-links {
        display: flex;
        flex-direction: row;
        gap: 0.5rem;
    }

    .project-grid {
        grid-template-columns: repeat(3, 1fr); 
    }
    
    .about-content {
        flex-direction: row; 
        align-items: flex-start;
        gap: 3rem;
    }

    .container {
        padding: 1.5rem 2rem;
    }
}