/* Base Styles */
:root {
    --bg-primary: #0d1117;
    --bg-secondary: #161b22;
    --border-color: #30363d;
    --text-primary: #c9d1d9;
    --text-secondary: #8b949e;
    --accent-color: #58a6ff;
    --accent-hover: #79c0ff;
    --card-hover-bg: #1c2128;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 16px;
}

/* Header & Navigation */
header {
    background: rgba(22, 27, 34, 0.85);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all 0.3s ease;
}

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

.logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--accent-color);
    text-decoration: none;
    background: linear-gradient(45deg, #58a6ff, #a371f7);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    transition: opacity 0.2s;
}

.logo:hover {
    opacity: 0.8;
}

nav {
    display: flex;
    gap: 24px;
}

nav a {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color 0.2s;
    position: relative;
}

nav a:hover {
    color: var(--accent-color);
}

nav a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -4px;
    left: 0;
    background-color: var(--accent-color);
    transition: width 0.3s ease;
}

nav a:hover::after {
    width: 100%;
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 101;
}

.mobile-menu-btn .bar {
    width: 100%;
    height: 3px;
    background-color: var(--text-primary);
    border-radius: 3px;
    transition: all 0.3s ease;
}

/* Profile Section */
.profile-section {
    padding: 64px 0;
}

.profile-grid {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 48px;
}

.profile-sidebar {
    display: flex;
    flex-direction: column;
    gap: 16px;
    position: sticky;
    top: 100px;
    height: fit-content;
}

.profile-avatar {
    width: 100%;
    aspect-ratio: 1;
    border-radius: 50%;
    border: 2px solid var(--border-color);
    object-fit: cover;
    transition: transform 0.3s ease, border-color 0.3s ease;
    box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}

.profile-avatar:hover {
    transform: scale(1.02);
    border-color: var(--accent-color);
}

.profile-name {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.profile-username {
    font-size: 20px;
    font-weight: 300;
    color: var(--text-secondary);
}

.profile-bio {
    font-size: 15px;
    color: var(--text-primary);
    margin: 16px 0;
    line-height: 1.6;
}

.profile-meta {
    display: flex;
    flex-direction: column;
    gap: 12px;
    font-size: 14px;
    color: var(--text-secondary);
}

.profile-meta-item {
    display: flex;
    align-items: center;
    gap: 10px;
    transition: color 0.2s;
}

.profile-meta-item:hover {
    color: var(--accent-color);
}

.profile-meta-item svg {
    width: 18px;
    height: 18px;
    fill: currentColor;
}

/* Main Content */
.profile-main {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.section-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 32px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.section-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.3);
    border-color: var(--accent-color);
}

.section-title {
    font-size: 22px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 24px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Experience & Education Items */
.experience-item,
.education-item,
.project-item {
    margin-bottom: 32px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--border-color);
    position: relative;
}

.experience-item:last-child,
.education-item:last-child,
.project-item:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.item-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 12px;
    flex-wrap: wrap;
    gap: 12px;
}

.item-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--accent-color);
}

.item-date {
    font-size: 14px;
    color: var(--text-secondary);
    background: rgba(56, 139, 253, 0.1);
    padding: 4px 12px;
    border-radius: 12px;
    font-weight: 500;
}

.item-subtitle {
    font-size: 15px;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.item-description {
    font-size: 15px;
    color: var(--text-primary);
}

.item-description ul {
    margin: 12px 0;
    padding-left: 24px;
}

.item-description li {
    margin: 8px 0;
}

/* Skills */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
}

.skill-category {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    transition: all 0.3s ease;
}

.skill-category:hover {
    border-color: var(--accent-color);
    transform: translateY(-2px);
}

.skill-category-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.skill-tag {
    background: rgba(56, 139, 253, 0.1);
    color: var(--accent-color);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 500;
    border: 1px solid transparent;
    transition: all 0.2s ease;
    cursor: default;
}

.skill-tag:hover {
    background: rgba(56, 139, 253, 0.2);
    border-color: var(--accent-color);
}

/* Pinned Projects */
.pinned-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
}

.pinned-repo {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 24px;
    transition: all 0.3s ease;
    text-decoration: none;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.pinned-repo:hover {
    border-color: var(--accent-color);
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}

.repo-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: 12px;
}

.repo-description {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.6;
    flex-grow: 1;
}

.repo-meta {
    display: flex;
    gap: 16px;
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: auto;
}

/* Certificates */
.certificates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.certificate-item {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 12px;
}

.certificate-item:hover {
    border-color: var(--accent-color);
    transform: translateY(-4px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

.certificate-item::before {
    content: '🏆';
    font-size: 20px;
}

/* Footer */
footer {
    text-align: center;
    padding: 64px 0;
    color: var(--text-secondary);
    font-size: 14px;
    border-top: 1px solid var(--border-color);
    margin-top: 64px;
    background: var(--bg-secondary);
}

/* Animations */
.fade-in-section {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
    will-change: opacity, visibility;
}

.fade-in-section.visible {
    opacity: 1;
    transform: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    .mobile-menu-btn {
        display: flex;
    }

    nav {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: var(--bg-secondary);
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        border-bottom: 1px solid var(--border-color);
        transform: translateY(-150%);
        transition: transform 0.3s ease;
        z-index: 99;
    }

    nav.active {
        transform: translateY(0);
        box-shadow: 0 10px 20px rgba(0,0,0,0.5);
    }

    .mobile-menu-btn.active .bar:nth-child(1) {
        transform: translateY(9px) rotate(45deg);
    }

    .mobile-menu-btn.active .bar:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-btn.active .bar:nth-child(3) {
        transform: translateY(-9px) rotate(-45deg);
    }

    .profile-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .profile-sidebar {
        position: static;
        text-align: center;
        align-items: center;
    }

    .profile-avatar {
        max-width: 200px;
        margin: 0 auto;
    }

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

    .item-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .item-date {
        margin-top: 4px;
    }
}