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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', sans-serif;
    line-height: 1.7;
    color: #333;
    background: #ffffff;
}

/* when mobile menu is open, lock body scroll */
.no-scroll {
    overflow: hidden;
    height: 100vh;
}

.container {
    max-width: 1200px;
    margin: auto;
    padding: 0 20px;
}

/* Header & Navigation */
header {
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fb 100%);
    color: #1a1a1a;
    padding: 18px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
    border-bottom: 1px solid #e8e8e8;
}

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

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

nav {
    position: relative;
}

.menu-toggle {
    display: none;
    background: #ffffff;
    border: 1px solid #d8d8d8;
    border-radius: 10px;
    font-size: 24px;
    cursor: pointer;
    color: #1a1a1a;
    padding: 10px 12px;
    transition: all 0.25s ease;
}

.menu-toggle:hover,
.menu-toggle:focus-visible {
    transform: translateY(-1px);
    border-color: #0066ff;
}

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

    nav ul {
        display: none;
        position: fixed;
        top: 80px;
        left: 10px;
        right: 10px;
        background: #ffffff;
        flex-direction: column;
        gap: 0;
        padding: 10px 0;
        border: 1px solid #e8e8e8;
        border-radius: 12px;
        box-shadow: 0 18px 35px rgba(0, 0, 0, 0.12);
        z-index: 9999;
        max-height: calc(100vh - 120px);
        overflow: auto;
        -webkit-overflow-scrolling: touch;
    }

    nav ul.active {
        display: flex;
    }

    nav ul li {
        padding: 10px 0;
        text-align: center;
        border-bottom: 1px solid #f0f0f0;
    }

    nav ul li:last-child {
        border-bottom: none;
    }
}

header h1 {
    font-size: 26px;
    font-weight: 700;
    letter-spacing: 0.3px;
    color: #1a1a1a;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 35px;
    align-items: center;
    justify-content: center;
}

nav a {
    color: #555;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

nav a:hover {
    color: #0066ff;
}

nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #0066ff;
    transition: width 0.3s ease;
}

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

/* Active / focus styles for navigation */
nav a.active {
    color: #0066ff;
    font-weight: 700;
}

nav a.active::after {
    width: 100%;
}

nav a:focus {
    outline: none;
    color: #0047b3;
}

nav a:focus-visible {
    outline: 2px solid rgba(0,102,255,0.18);
    outline-offset: 4px;
}

/* Sections */
section {
    padding: 80px 0;
    background: #ffffff;
    margin: 0;
    border-radius: 0;
    box-shadow: none;
}

section:nth-child(odd) {
    background: #f8f9fb;
}

section h2 {
    font-size: 42px;
    margin-bottom: 50px;
    text-align: center;
    color: #1a1a1a;
    position: relative;
    padding-bottom: 20px;
    font-weight: 700;
}

section h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, #0066ff, #0099ff);
    border-radius: 2px;
}

#home {
    background: linear-gradient(135deg, #ffffff 0%, #f0f4ff 100%);
    color: #1a1a1a;
    text-align: center;
    padding: 120px 0;
    margin: 0;
    border-radius: 0;
    box-shadow: none;
}

#home h2 {
    color: #1a1a1a;
    font-size: 52px;
    margin-bottom: 20px;
}

#home p {
    font-size: 18px;
    margin-bottom: 15px;
    color: #666;
    font-weight: 400;
}

.cta-button {
    display: inline-block;
    background: linear-gradient(135deg, #0066ff 0%, #0099ff 100%);
    color: #fff;
    padding: 14px 32px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    margin-top: 20px;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    font-size: 15px;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 35px rgba(0, 102, 255, 0.3);
}

html {
    scroll-behavior: smooth;
}

:focus-visible {
    outline: 2px solid #0066ff;
    outline-offset: 3px;
}

.page-intro {
    text-align: center;
    max-width: 900px;
    margin: 0 auto 40px;
    color: #585858;
    font-size: 18px;
    line-height: 1.8;
}

.section-subtitle {
    text-align: center;
    max-width: 760px;
    margin: 0 auto 40px;
    color: #666;
    font-size: 17px;
}

.highlight-panel,
.form-card,
.info-panel,
.tool-panel,
.contact-card {
    background: #f0f4ff;
    border-radius: 14px;
    padding: 30px;
    border: 1px solid rgba(0, 102, 255, 0.16);
}

.highlight-panel {
    border-left: 4px solid #0066ff;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    align-items: start;
}

.tool-panel {
    background: #ffffff;
    border: 1px solid #e8e8e8;
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.04);
}

.project-tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 35px;
}

.section-tagline {
    color: #0066ff;
    font-weight: 700;
    margin-bottom: 18px;
}

.card h3,
.info-panel h3,
.form-card h3,
.tool-panel h3 {
    color: #0066ff;
}

.card p,
.info-panel p,
.form-card p,
.tool-panel p {
    color: #666;
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 35px;
    margin-top: 50px;
}

.card {
    background: #ffffff;
    padding: 35px;
    border-radius: 12px;
    transition: all 0.4s ease;
    border: 1px solid #e8e8e8;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
    color: #333;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(0, 102, 255, 0.15);
    border-color: #0066ff;
}

.card h3 {
    color: #0066ff;
    margin-bottom: 15px;
    font-size: 22px;
    font-weight: 600;
}

.card p {
    color: #666;
    line-height: 1.8;
    font-size: 15px;
}

/* Skills Section */
.skill-item {
    margin-bottom: 30px;
}

.skill-name {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    font-weight: 600;
    color: #0066ff;
}

.progress-bar {
    background: #e8e8e8;
    height: 8px;
    border-radius: 10px;
    overflow: hidden;
}

.progress-fill {
    background: linear-gradient(90deg, #0066ff, #0099ff);
    height: 100%;
    border-radius: 10px;
    transition: width 0.5s ease;
}

/* Skills List */
.skills-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
    gap: 15px;
    margin-top: 30px;
}

.skill-tag {
    background: linear-gradient(135deg, #0066ff 0%, #0099ff 100%);
    color: #fff;
    padding: 12px 20px;
    border-radius: 8px;
    text-align: center;
    font-weight: 500;
    transition: all 0.3s ease;
    cursor: default;
    border: 1px solid #0066ff;
    font-size: 14px;
}

.skill-tag:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 102, 255, 0.3);
}

/* Form Styling */
form {
    max-width: 600px;
    margin: 40px auto;
    background: #f8f9fb;
    padding: 35px;
    border-radius: 12px;
    border: 1px solid #e8e8e8;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #1a1a1a;
    font-weight: 600;
    font-size: 14px;
}

input, textarea {
    width: 100%;
    padding: 12px 14px;
    margin-bottom: 20px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-family: inherit;
    font-size: 14px;
    transition: all 0.3s ease;
    background: #ffffff;
    color: #333;
}

input:focus, textarea:focus {
    outline: none;
    border-color: #0066ff;
    box-shadow: 0 0 0 4px rgba(0, 102, 255, 0.1);
    background: #fff;
}

button {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, #0066ff 0%, #0099ff 100%);
    color: #fff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 102, 255, 0.3);
}

/* Footer */
footer {
    background: #1a1a1a;
    color: #fff;
    text-align: center;
    padding: 40px 0;
    margin-top: 60px;
    border-top: 1px solid #333;
}

footer p {
    margin: 0;
    font-size: 14px;
}

.social-links {
    margin-top: 15px;
    display: flex;
    justify-content: center;
    gap: 25px;
}

.social-links a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    font-size: 14px;
}

.social-links a:hover {
    color: #0066ff;
    transform: translateY(-2px);
}

/* Responsive: Tablet (768px and below) */
@media (max-width: 768px) {
    header {
        padding: 15px 0;
    }

    header nav .container {
        flex-direction: column;
        gap: 15px;
    }

    header h1 {
        font-size: 22px;
        text-align: center;
    }

    nav ul {
        flex-direction: column;
        gap: 10px;
        justify-content: center;
    }

    nav a {
        font-size: 13px;
        padding: 8px 0;
        text-align: center;
        display: block;
    }

    section {
        padding: 60px 0;
    }

    section h2 {
        font-size: 32px;
        margin-bottom: 30px;
    }

    #home {
        padding: 80px 0;
    }

    #home h2 {
        font-size: 36px;
        margin-bottom: 15px;
    }

    #home p {
        font-size: 16px;
        margin-bottom: 12px;
    }

    .cta-button {
        padding: 12px 24px;
        font-size: 14px;
        margin: 10px 5px;
        display: inline-block;
    }

    .cards-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }

    .card {
        padding: 25px;
    }

    .card h3 {
        font-size: 18px;
        margin-bottom: 12px;
    }

    .card p {
        font-size: 14px;
    }

    .skills-list {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    .skill-tag {
        padding: 10px 15px;
        font-size: 12px;
    }

    form {
        padding: 20px;
        margin: 30px auto;
    }

    label {
        font-size: 13px;
        margin-bottom: 6px;
    }

    input, textarea {
        padding: 10px 12px;
        font-size: 14px;
        margin-bottom: 15px;
    }

    button {
        padding: 12px;
        font-size: 14px;
    }

    footer {
        padding: 30px 0;
    }

    .social-links {
        gap: 15px;
    }

    .social-links a {
        font-size: 13px;
    }
}

/* Mobile (480px and below) */
@media (max-width: 480px) {
    body {
        font-size: 14px;
    }

    .container {
        padding: 0 12px;
    }

    header {
        padding: 12px 0;
        box-shadow: 0 2px 10px rgba(0, 0, 0, 0.06);
    }

    header h1 {
        font-size: 18px;
    }

    nav ul {
        gap: 8px;
    }

    nav a {
        font-size: 12px;
        padding: 6px 0;
    }

    section {
        padding: 40px 0;
        margin: 0;
    }

    section h2 {
        font-size: 26px;
        margin-bottom: 25px;
        padding-bottom: 15px;
    }

    section h2::after {
        width: 50px;
    }

    #home {
        padding: 60px 0;
    }

    #home h2 {
        font-size: 28px;
        margin-bottom: 12px;
    }

    #home p {
        font-size: 15px;
        margin-bottom: 10px;
    }

    .cta-button {
        padding: 11px 20px;
        font-size: 13px;
        margin: 8px 4px;
        border-radius: 4px;
    }

    .cards-grid {
        gap: 20px;
    }

    .card {
        padding: 20px;
        border-radius: 8px;
    }

    .card:hover {
        transform: translateY(-5px);
    }

    .card h3 {
        font-size: 16px;
        margin-bottom: 10px;
    }

    .card p {
        font-size: 13px;
        line-height: 1.6;
    }

    .skill-item {
        margin-bottom: 20px;
    }

    .skill-name {
        font-size: 13px;
        margin-bottom: 6px;
    }

    .progress-bar {
        height: 6px;
    }

    .skills-list {
        grid-template-columns: 1fr;
        gap: 10px;
    }

    .skill-tag {
        padding: 9px 12px;
        font-size: 11px;
        border-radius: 6px;
    }

    form {
        padding: 18px;
        margin: 25px auto;
        border-radius: 8px;
    }

    label {
        font-size: 12px;
        margin-bottom: 5px;
    }

    input, textarea {
        padding: 9px 10px;
        font-size: 13px;
        margin-bottom: 12px;
        border-radius: 4px;
    }

    textarea {
        min-height: 100px;
    }

    button {
        padding: 10px;
        font-size: 13px;
        border-radius: 4px;
    }

    footer {
        padding: 25px 0;
    }

    footer p {
        font-size: 13px;
    }

    .social-links {
        gap: 12px;
        margin-top: 12px;
    }

    .social-links a {
        font-size: 12px;
    }
}

/* Small mobile (400px and below) */
@media (max-width: 400px) {
    section h2 {
        font-size: 22px;
    }

    .card h3 {
        font-size: 15px;
    }

    nav ul {
        gap: 6px;
    }

    nav a {
        font-size: 11px;
    }
}

/* Mobile-specific layouts for special sections */
@media (max-width: 768px) {
    /* How I Work section - make grid responsive */
    div[style*="grid-template-columns: 1fr 1fr 1fr"] {
        grid-template-columns: 1fr !important;
        gap: 20px !important;
    }

    div[style*="grid-template-columns: 1fr 1fr"] {
        grid-template-columns: 1fr !important;
        gap: 15px !important;
    }

    /* Contact section layout */
    div[style*="display: grid"] {
        grid-template-columns: 1fr !important;
    }

    /* Interactive projects grid */
    div[style*="display: grid"][style*="grid-template-columns"] {
        grid-template-columns: 1fr !important;
    }
}

@media (max-width: 480px) {
    /* Make all 4-column grids single column */
    div[style*="grid-template-columns: repeat(4"] {
        grid-template-columns: repeat(2, 1fr) !important;
        gap: 6px !important;
    }
}