/* Reset & Variables */
:root {
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-color: #212529;
    --muted-color: #6c757d;
    --accent-color: #198754;
    --hover-color: #157347;
    --nav-height: 70px;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 6px 20px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --bg-color: #121212;
    --card-bg: #1e1e1e;
    --text-color: #e0e0e0;
    --muted-color: #a0a0a0;
    --accent-color: #28a745; /* A slightly brigher green for dark bg */
    --hover-color: #218838;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    --shadow-hover: 0 6px 20px rgba(0, 0, 0, 0.3);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

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

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

.fade-in {
    animation: fadeIn 1s ease-in-out forwards;
}

.fade-in-up {
    animation: fadeInUp 0.8s ease-in-out forwards;
}

/* Utilities */
a {
    text-decoration: none;
    color: var(--accent-color);
    transition: color 0.3s ease;
}
a:hover {
    color: var(--hover-color);
}
ul {
    list-style: none;
}
.highlight {
    color: var(--accent-color);
    font-weight: 600;
}
.section {
    padding: 100px 20px;
    max-width: 1100px;
    margin: 0 auto;
    text-align: center;
}
.section-title {
    font-size: 2.5rem;
    margin-bottom: 25px;
    position: relative;
    display: inline-block;
    padding-bottom: 10px;
}
.section-title::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--accent-color);
    border-radius: 2px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    background: var(--accent-color);
    color: #fff;
    font-weight: bold;
    border-radius: 50px;
    margin-top: 20px;
    transition: background 0.3s, transform 0.3s, box-shadow 0.3s;
    box-shadow: var(--shadow);
}
.btn:hover {
    background: var(--hover-color);
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
    color: #fff;
}
.btn-outline {
    background: transparent;
    border: 2px solid var(--accent-color);
    color: var(--accent-color);
}
.btn-outline:hover {
    background: var(--accent-color);
    color: #fff;
}

/* Navbar */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 40px;
    height: var(--nav-height);
    background: var(--card-bg);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    transition: top 0.3s;
}
.logo {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--text-color);
}
.logo span {
    color: var(--accent-color);
}
.nav-links {
    display: flex;
    gap: 30px;
}
.nav-links a {
    color: var(--text-color);
    font-weight: 500;
    position: relative;
    padding: 5px 0;
}
.nav-links a::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: width 0.3s;
}
.nav-links a:hover::after {
    width: 100%;
}

.theme-switch {
    font-size: 1.3rem;
    cursor: pointer;
    color: var(--text-color);
}
.theme-switch .fa-moon {
    display: none;
}
[data-theme="dark"] .theme-switch .fa-moon {
    display: inline-block;
}
[data-theme="dark"] .theme-switch .fa-sun {
    display: none;
}

.hamburger {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column; 
    justify-content: center;
    align-items: center; 
    text-align: center;
    padding: 0 20px;
}
.hero-content {
    max-width: 700px;
    animation-delay: 0.2s; 
    display: flex;
    flex-direction: column;
    align-items: center;
}
.profile-img-container {
    margin-bottom: 25px;
}
.profile-img {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    border: 5px solid var(--card-bg);
    box-shadow: 0 0 25px rgba(0, 0, 0, 0.1);
    animation: pulse 2s infinite ease-in-out;
}
.hero h1 {
    font-size: 3.5rem;
    line-height: 1.2;
    margin-bottom: 15px;
}
.role {
    font-size: 1.3rem;
    color: var(--muted-color);
    margin-bottom: 25px;
}
.social-icons {
    font-size: 1.8rem;
    display: flex;
    gap: 25px;
}
.social-icons a {
    color: var(--muted-color);
    transition: transform 0.3s, color 0.3s;
}
.social-icons a:hover {
    color: var(--accent-color);
    transform: scale(1.2);
}

.about-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.skills-container {
    margin-top: 40px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
    text-align: left;
}

.skill {
    display: flex;
    flex-direction: column;
}

.skill-name {
    font-weight: 600;
    margin-bottom: 8px;
}

.skill-bar {
    width: 100%;
    height: 12px;
    background-color: #e0e0e0;
    border-radius: 10px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    width: 0; 
    background-color: var(--accent-color);
    border-radius: 10px;
    transition: width 1.5s cubic-bezier(0.25, 1, 0.5, 1);
}

.timeline {
    position: relative;
    max-width: 800px;
    margin: 50px auto;
    padding: 20px 0;
}

.timeline::after {
    content: "";
    position: absolute;
    width: 3px;
    background: var(--accent-color);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -1.5px;
    border-radius: 3px;
}

.timeline-item {
    padding: 10px 40px;
    position: relative;
    background: inherit;
    width: 50%;
    opacity: 0; 
    transform: translateY(50px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.timeline-item.is-visible {
    opacity: 1;
    transform: translateY(0);
}

.timeline-item:nth-child(odd) {
    left: 0;
    padding-right: 30px;
    text-align: right;
}

.timeline-item:nth-child(even) {
    left: 50%;
    padding-left: 30px;
    text-align: left;
}

.timeline-dot {
    content: "";
    position: absolute;
    width: 18px;
    height: 18px;
    background: var(--bg-color);
    border: 4px solid var(--accent-color);
    top: 28px;
    right: -9px;
    border-radius: 50%;
    z-index: 1;
}

.timeline-item:nth-child(even) .timeline-dot {
    left: -9px;
}

.timeline-content {
    padding: 20px;
    background: var(--card-bg);
    border-radius: 8px;
    box-shadow: var(--shadow);
    position: relative;
}

.timeline-date {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: 8px;
    display: inline-block;
}

.timeline-content h3 {
    margin-bottom: 5px;
    font-size: 1.3rem;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.project-card {
    background: var(--card-bg);
    padding: 25px;
    border-radius: 10px;
    text-align: left;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
    display: flex;
    flex-direction: column;
}
.project-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
}
.project-card a {
    color: inherit;
    display: flex;
    flex-direction: column;
    height: 100%;
}
.project-card a:hover {
    color: inherit;
}

.project-card h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: var(--accent-color);
}
.project-card p {
    font-size: 0.95rem;
    color: var(--muted-color);
    margin-bottom: 20px;
    flex-grow: 1;
    min-height: 60px;
}
.project-stats {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: #999;
    margin-top: auto;
    align-items: center;
}
.lang-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    display: inline-block;
    margin-right: 6px;
}


#filter-buttons {
    margin: 30px 0;
    display: flex;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

.filter-btn {
    background: var(--card-bg);
    color: var(--text-color);
    border: 1px solid #ddd;
    box-shadow: none;
}

.filter-btn.active,
.filter-btn:hover {
    background: var(--accent-color);
    color: #fff;
    border-color: var(--accent-color);
}

.project-card.hide {
    display: none;
}

.project-tech {
    margin-top: 15px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.project-tech span {
    font-size: 0.8rem;
    background: #e9ecef;
    padding: 4px 12px;
    border-radius: 20px;
    color: var(--muted-color);
}

.contact-form {
    max-width: 600px;
    margin: 40px auto 0;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.form-group {
    position: relative;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid #ccc;
    border-radius: 8px;
    background: var(--card-bg);
    font-size: 1rem;
    color: var(--text-color);
    transition: border-color 0.3s;
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--accent-color);
}

.form-group small.error-message {
    color: #e74c3c;
    position: absolute;
    left: 10px;
    bottom: -18px;
    font-size: 0.8rem;
    opacity: 0;
    transition: opacity 0.3s;
}

.form-group.error input,
.form-group.error textarea {
    border-color: #e74c3c;
}

.form-group.error small.error-message {
    opacity: 1;
}

.form-message {
    margin-top: 15px;
    padding: 15px;
    border-radius: 8px;
    text-align: center;
    font-weight: 500;
    display: none;
}

.form-message.success {
    background-color: #d4edda;
    color: #155724;
    display: block;
}

.form-message.error {
    background-color: #f8d7da;
    color: #721c24;
    display: block;
}

footer {
    padding: 30px;
    text-align: center;
    background: #e9ecef;
    font-size: 0.9rem;
    color: var(--muted-color);
    margin-top: 60px;
}

#back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    margin: 0;
    font-size: 1.2rem;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: opacity 0.4s, visibility 0.4s, transform 0.4s;
    z-index: 999;
}

#back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    .hamburger {
        display: block;
    }

    .hero {
        text-align: center;
        padding-top: var(--nav-height);
    }
    .hero-content {
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    .hero h1 {
        font-size: 2.5rem;
    }
    .social-icons {
        justify-content: center;
    }
}