:root {
    /* --- Colors (Apple System Colors) --- */
    --c-primary: #000000;
    --c-secondary: #86868b;
    --c-accent: #0066cc;
    /* Apple Link Blue */
    --c-accent-hover: #004499;
    --c-bg-body: #ffffff;
    --c-bg-section: #f5f5f7;
    --c-bg-card: #ffffff;
    --c-border: #d2d2d7;

    /* --- Typography --- */
    --font-stack: "SF Pro Text", "SF Pro Icons", "Helvetica Neue", "Helvetica", "Arial", sans-serif;
    --font-heading: "SF Pro Display", "SF Pro Icons", "Helvetica Neue", "Helvetica", "Arial", sans-serif;

    /* Weights */
    --fw-regular: 400;
    --fw-medium: 500;
    --fw-semibold: 600;
    --fw-bold: 700;

    /* Sizes (Mobile First) */
    --fz-h1: 40px;
    --fz-h2: 32px;
    --fz-h3: 24px;
    --fz-body: 17px;
    --fz-small: 14px;
    --fz-eyebrow: 12px;

    /* --- Spacing (8px Grid) --- */
    --space-1: 8px;
    --space-2: 16px;
    --space-3: 24px;
    --space-4: 32px;
    --space-5: 40px;
    --space-6: 48px;
    --space-8: 64px;
    --space-10: 80px;

    /* --- Layout --- */
    --container-width: 980px;
    --radius-s: 8px;
    --radius-m: 12px;
    --radius-l: 24px;
    --radius-xl: 30px;

    /* --- Effects --- */
    --shadow-soft: 0 4px 24px rgba(0, 0, 0, 0.04);
    --shadow-hover: 0 8px 32px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
}

/* --- Resets & Base --- */
html {
    box-sizing: border-box;
    font-size: 100%;
    scroll-behavior: smooth;
}

*,
*:before,
*:after {
    box-sizing: inherit;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-stack);
    background-color: var(--c-bg-body);
    color: var(--c-primary);
    line-height: 1.47059;
    /* Apple standard */
    letter-spacing: -0.022em;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

img {
    max-width: 100%;
    display: block;
}

a {
    color: var(--c-accent);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--c-accent-hover);
    text-decoration: underline;
}

ul {
    list-style: none;
}

/* --- Typography Utilities --- */
h1,
h2,
h3 {
    font-family: var(--font-heading);
    color: var(--c-primary);
    line-height: 1.1;
    letter-spacing: -0.005em;
}

h1 {
    font-size: var(--fz-h1);
    font-weight: var(--fw-semibold);
}

h2 {
    font-size: var(--fz-h2);
    font-weight: var(--fw-semibold);
}

h3 {
    font-size: var(--fz-h3);
    font-weight: var(--fw-semibold);
}

p {
    margin-bottom: 1em;
}

.eyebrow {
    font-size: var(--fz-eyebrow);
    font-weight: var(--fw-semibold);
    text-transform: uppercase;
    letter-spacing: -0.01em;
    color: var(--c-secondary);
    margin-bottom: var(--space-1);
    display: block;
}

/* --- Components --- */

/* Buttons */
.button-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background-color: var(--c-accent);
    color: #fff !important;
    font-size: var(--fz-small);
    font-weight: var(--fw-medium);
    padding: var(--space-1) var(--space-2);
    border-radius: 980px;
    /* Pill shape */
    transition: var(--transition);
    text-decoration: none !important;
}

.button-primary:hover {
    background-color: var(--c-accent-hover);
    transform: scale(1.02);
}

.link-arrow {
    font-size: var(--fz-body);
    font-weight: var(--fw-medium);
    display: inline-flex;
    align-items: center;
}

.link-arrow::after {
    content: "›";
    margin-left: 4px;
    font-size: 1.2em;
    transition: transform 0.2s;
}

.link-arrow:hover::after {
    transform: translateX(3px);
}

/* --- Layout Sections --- */

/* Navigation */
.global-nav {
    position: sticky;
    top: 0;
    width: 100%;
    height: 48px;
    background-color: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.nav-content {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--space-3);
    height: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-size: var(--fz-small);
    font-weight: var(--fw-semibold);
    color: var(--c-primary);
}

.nav-list {
    display: none;
    /* Hidden on mobile */
}

/* Mobile Menu Trigger */
.nav-mobile-trigger {
    width: 20px;
    height: 14px;
    position: relative;
    cursor: pointer;
    z-index: 1001;
}

.nav-mobile-trigger span {
    display: block;
    width: 100%;
    height: 2px;
    /* Thicker for visibility */
    background-color: var(--c-primary);
    position: absolute;
    left: 0;
    transition: var(--transition);
}

.nav-mobile-trigger span:first-child {
    top: 0;
}

.nav-mobile-trigger span:last-child {
    bottom: 0;
}

/* Hero */
.hero-section {
    padding: var(--space-8) var(--space-3) var(--space-4);
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero-headline {
    margin-bottom: var(--space-2);
}

.hero-subhead {
    font-size: 20px;
    line-height: 1.4;
    color: var(--c-primary);
    margin-bottom: 0;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
    align-items: center;
}

/* Profile / About */
.section-profile {
    background-color: var(--c-bg-section);
    padding: var(--space-10) var(--space-3);
    text-align: center;
}

.section-headline {
    margin-bottom: var(--space-3);
}

.section-text {
    font-size: 19px;
    line-height: 1.5;
    color: var(--c-secondary);
    max-width: 640px;
    margin: 0 auto;
}

/* Grid / Bento */
.section-grid {
    padding: var(--space-4) var(--space-3) var(--space-6);
    background-color: var(--c-bg-body);
}

.grid-container {
    max-width: var(--container-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-3);
}

.courses-grid {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-3);
}

@media (min-width: 768px) {
    .courses-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-4);
    }
}

.grid-item {
    background-color: var(--c-bg-section);
    border-radius: var(--radius-xl);
    padding: var(--space-5) var(--space-4);
    display: flex;
    flex-direction: column;
    align-items: stretch;
    text-align: left;
    position: relative;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    min-height: 400px;
}

.grid-item:hover {
    transform: scale(1.01);
    box-shadow: var(--shadow-hover);
}

.grid-item.dark-mode {
    background-color: #1d1d1f;
    color: #fff;
}

.grid-item.dark-mode h3,
.grid-item.dark-mode p,
.grid-item.dark-mode ul {
    color: #fff;
}

.grid-item.dark-mode .eyebrow {
    color: rgba(255, 255, 255, 0.6);
}

.grid-item.dark-mode .link-arrow {
    color: #2997ff !important;
}

.item-content {
    display: flex;
    flex-direction: column;
    height: 100%;
    width: 100%;
}

.grid-item .eyebrow {
    text-align: center;
}

.grid-item h3 {
    margin-bottom: var(--space-2);
    font-size: 28px;
    text-align: center;
}

.grid-item p,
.grid-item ul {
    font-size: 15px;
    line-height: 1.5;
    color: var(--c-secondary);
    margin-bottom: var(--space-3);
    flex-grow: 1;
}

.grid-item ul {
    list-style: none;
    padding: 0;
    margin-bottom: var(--space-3);
}

.grid-item ul li {
    position: relative;
    padding-left: 20px;
    margin-bottom: var(--space-1);
}

.grid-item ul li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--c-accent);
    font-weight: bold;
}

.grid-item.dark-mode ul li:before {
    color: #2997ff;
}

.grid-item .link-arrow {
    margin-top: auto;
    align-self: flex-start;
}

/* About Section Specific Styles */
.about-item {
    text-align: left;
}

.about-content {
    flex-direction: row;
    gap: var(--space-5);
    align-items: center;
}

.about-image {
    flex-shrink: 0;
}

.about-image img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid rgba(0, 0, 0, 0.05);
}

.about-text {
    flex: 1;
}

.about-text .eyebrow,
.about-text h3 {
    text-align: left;
}

.about-text p {
    text-align: left;
    max-width: none;
}

/* Course Card Backgrounds */
.course-freelance,
.course-microstock {
    position: relative;
    overflow: hidden;
}

.course-freelance::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('../images/freelance-workspace.jpg');
    background-size: cover;
    background-position: center;
    opacity: 0.15;
    z-index: 0;
}

.course-microstock::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('../images/microstock-workspace.jpg');
    background-size: cover;
    background-position: center;
    opacity: 0.15;
    z-index: 0;
}

.course-freelance .item-content,
.course-microstock .item-content {
    position: relative;
    z-index: 1;
}

.course-freelance {
    background-color: #1c1c1e;
}

.course-microstock {
    background-color: #2d2d2d;
    color: #fff;
}

.course-microstock h3,
.course-microstock p,
.course-microstock ul {
    color: #fff;
}

.course-microstock .eyebrow {
    color: rgba(255, 255, 255, 0.7);
}

.course-microstock ul li:before {
    color: #ffa500;
}


/* Contact */
.section-contact {
    padding: var(--space-8) var(--space-3);
    text-align: center;
    background-color: var(--c-bg-section);
}

.social-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-3);
    margin-top: var(--space-4);
}

.social-link {
    font-size: var(--fz-small);
    color: var(--c-primary);
    padding: var(--space-1) var(--space-2);
    border: 1px solid var(--c-border);
    border-radius: 980px;
    transition: var(--transition);
}

.social-link:hover {
    background-color: var(--c-primary);
    color: #fff;
    border-color: var(--c-primary);
    text-decoration: none;
}


/* Footer */
footer {
    padding: var(--space-4) var(--space-3);
    text-align: center;
    font-size: 11px;
    color: var(--c-secondary);
    border-top: 1px solid var(--c-border);
}

/* --- Media Queries (Tablet & Desktop) --- */
@media (min-width: 768px) {
    :root {
        --fz-h1: 56px;
        --fz-h2: 48px;
        --fz-h3: 32px;
        --fz-body: 21px;
        --space-3: 32px;
    }

    .nav-list {
        display: flex;
        gap: var(--space-4);
    }

    .nav-mobile-trigger {
        display: none;
    }

    .nav-list a {
        font-size: 12px;
        color: var(--c-primary);
        opacity: 0.8;
        transition: opacity 0.2s;
    }

    .nav-list a:hover {
        opacity: 1;
        text-decoration: none;
    }

    .hero-section {
        padding: 120px 0;
    }

    .cta-links {
        flex-direction: row;
    }

    .grid-container {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-4);
    }

    .large-item {
        grid-column: span 2;
        padding-top: 80px;
        padding-bottom: 80px;
    }

    .hero-subhead {
        font-size: 24px;
    }

    .about-content {
        flex-direction: row;
        text-align: left;
    }

    .about-image img {
        width: 220px;
        height: 220px;
    }
}

/* Mobile-specific styles */
@media (max-width: 767px) {
    .about-content {
        flex-direction: column;
        text-align: center;
        gap: var(--space-4);
    }

    .about-text .eyebrow,
    .about-text h3,
    .about-text p {
        text-align: center;
    }

    .about-image img {
        width: 180px;
        height: 180px;
    }
}

/* --- Mobile Menu State --- */
.nav-open {
    overflow: hidden;
}

.nav-overlay {
    position: fixed;
    top: 48px;
    left: 0;
    width: 100%;
    height: calc(100vh - 48px);
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    z-index: 999;
    display: flex;
    flex-direction: column;
    padding: 40px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.nav-overlay.active {
    opacity: 1;
    visibility: visible;
}

.nav-overlay a {
    font-size: 24px;
    font-weight: var(--fw-semibold);
    color: var(--c-primary);
    margin-bottom: 24px;
    border-bottom: 1px solid var(--c-border);
    padding-bottom: 10px;
}