/* =================================
   1. DESIGN SYSTEM
================================= */

:root {

    /* Colours */
    --color-background: #F5F3EE;
    --color-text: #252525;
    --color-muted: #77736B;
    --color-border: #DCD8CE;
    --color-accent: #526B62;
    --color-accent-secondary: #B7A58A;

    /* Typography */
    --font-heading: 'DM Serif Display', Georgia, serif;
    --font-body: 'Inter', Arial, sans-serif;

    /* Layout */
    --content-width: 1120px;
    --page-padding: 32px;

    /* Spacing */
    --space-xs: 8px;
    --space-sm: 16px;
    --space-md: 24px;
    --space-lg: 40px;
    --space-xl: 64px;
    --space-xxl: 112px;

}

/* =================================
   DARK THEME
================================= */

[data-theme="dark"] {
    --color-background: #252525;
    --color-text: #F5F3EE;
    --color-muted: #B8B4AA;
    --color-border: #49463F;
    --color-accent: #A6B9AE;
    --color-accent-secondary: #B7A58A;
}


/* =================================
   2. GLOBAL RESET
================================= */

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


/* =================================
   3. BASE STYLES
================================= */

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--color-background);
    color: var(--color-text);
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.7;
}


/* =================================
   4. TYPOGRAPHY
================================= */

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-heading);
    font-weight: 400;
}

body,
button,
input,
textarea {
    font-family: var(--font-body);
}


/* =================================
   5. NAVIGATION
================================= */

header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--color-background);
    border-bottom: 1px solid var(--color-border);
}

nav {
    max-width: var(--content-width);
    height: 76px;
    margin: 0 auto;
    padding: 0 var(--page-padding);

    display: flex;
    align-items: center;
    justify-content: space-between;
}

.site-name {
    color: var(--color-text);
    font-family: var(--font-heading);
    font-size: 24px;
    text-decoration: none;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    color: var(--color-muted);
    font-size: 14px;
    text-decoration: none;
    transition: color 0.2s ease;
}

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

#theme-toggle {
    background: none;
    border: 1px solid var(--color-border);
    border-radius: 50px;
    padding: 8px 14px;
    color: var(--color-text);
    cursor: pointer;
    font-size: 13px;
}

/* =================================
   NAVIGATION DROPDOWN
================================= */

.nav-dropdown {
    position: relative;
}

.dropdown-toggle {
    background: none;
    border: none;
    color: var(--color-muted);
    font-family: var(--font-body);
    font-size: 14px;
    cursor: pointer;
    transition: color 0.3s ease;
}

.dropdown-toggle:hover {
    color: var(--color-accent);
}

.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    min-width: 170px;
    padding: 10px 0;
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    z-index: 200;
}

.dropdown-menu a {
    display: block;
    padding: 10px 16px;
    color: var(--color-muted);
    font-size: 13px;
    text-decoration: none;
}

.dropdown-menu a:hover {
    color: var(--color-accent);
    background-color: var(--color-border);
}


/* =================================
   6. HERO SECTION
================================= */

.hero {
    max-width: 900px;
    min-height: 600px;
    margin: 0 auto;
    padding: 120px 32px;

    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;

    text-align: center;
}

.hero-overline {
    color: var(--color-accent);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 3px;
    margin-bottom: 28px;
}

.hero h1 {
    max-width: 850px;
    font-size: 64px;
    line-height: 1.15;
    font-weight: 400;
    margin-bottom: 28px;
}

.hero-description {
    max-width: 600px;
    color: var(--color-muted);
    font-size: 17px;
    margin-bottom: 36px;
}

.hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 28px;
}

.hero-actions a {
    color: var(--color-accent);
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
    border-bottom: 1px solid var(--color-accent);
    padding-bottom: 4px;
    transition: color 0.2s ease;
}

.hero-actions a:hover {
    color: var(--color-text);
}


/* =================================
   7. RESPONSIVE DESIGN
================================= */

@media (max-width: 768px) {

    :root {
        --page-padding: 20px;
        --space-xxl: 72px;
    }

    nav {
        height: 68px;
    }

    .site-name {
        font-size: 21px;
    }

    .nav-links {
        gap: 16px;
    }

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

    .hero {
        min-height: 540px;
        padding: 80px 20px;
    }

    .hero h1 {
        font-size: 46px;
    }

    .hero-description {
        font-size: 16px;
    }
}


@media (max-width: 480px) {

    .nav-links {
        gap: 10px;
    }

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

    #theme-toggle {
        padding: 6px 9px;
        font-size: 11px;
    }

    .hero {
        min-height: 500px;
    }

    .hero h1 {
        font-size: 38px;
    }

    .hero-overline {
        font-size: 10px;
        letter-spacing: 2px;
    }

    .hero-actions {
        gap: 20px;
    }
}


/* =================================
   8. EXPERTISE SECTION
================================= */

.expertise {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: var(--space-xxl) var(--page-padding);
    border-top: 1px solid var(--color-border);
}

.section-heading {
    margin-bottom: 56px;
}

.section-overline {
    color: var(--color-accent);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 2px;
    margin-bottom: 12px;
}

.section-heading h2 {
    font-size: 42px;
    line-height: 1.2;
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 48px 64px;
}

.expertise-item {
    padding-top: 20px;
    border-top: 1px solid var(--color-border);
}

.expertise-item h3 {
    font-size: 24px;
    margin-bottom: 12px;
}

.expertise-item p {
    max-width: 420px;
    color: var(--color-muted);
    font-size: 15px;
}


/* Mobile layout */

@media (max-width: 768px) {

    .expertise {
        padding-top: 72px;
        padding-bottom: 72px;
    }

    .section-heading {
        margin-bottom: 40px;
    }

    .section-heading h2 {
        font-size: 36px;
    }

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

    .expertise-item h3 {
        font-size: 22px;
    }
}


/* =================================
   9. PROJECTS SECTION
================================= */

.projects {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: var(--space-xxl) var(--page-padding);
    border-top: 1px solid var(--color-border);
}

.section-description {
    max-width: 550px;
    margin-top: 16px;
    color: var(--color-muted);
    font-size: 16px;
}

.project-list {
    margin-top: 48px;
}

.project-item {
    padding: 32px 0;
    border-top: 1px solid var(--color-border);
}

.project-meta {
    display: flex;
    justify-content: space-between;
    color: var(--color-accent);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 1.5px;
    margin-bottom: 20px;
}

.project-item h3 {
    font-size: 30px;
    margin-bottom: 12px;
}

.project-item > p {
    max-width: 650px;
    color: var(--color-muted);
    font-size: 15px;
}

.project-links {
    margin-top: 24px;
}

.project-links a {
    color: var(--color-accent);
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
    border-bottom: 1px solid var(--color-accent);
    padding-bottom: 4px;
}

.project-links a:hover {
    color: var(--color-text);
}


@media (max-width: 768px) {

    .projects {
        padding-top: 72px;
        padding-bottom: 72px;
    }

    .project-item h3 {
        font-size: 26px;
    }
}


/* =================================
   10. APPLICATIONS SECTION
================================= */

.applications {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: var(--space-xxl) var(--page-padding);
    border-top: 1px solid var(--color-border);
}

.application-list {
    margin-top: 48px;
}

.application-item {
    padding: 32px 0;
    border-top: 1px solid var(--color-border);
}

.application-meta {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
    color: var(--color-accent);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 1.5px;
    margin-bottom: 20px;
}

.application-item h3 {
    font-size: 30px;
    margin-bottom: 12px;
}

.application-item p {
    max-width: 650px;
    color: var(--color-muted);
    font-size: 15px;
}

.application-status {
    display: inline-block;
    margin-top: 24px;
    padding: 6px 12px;
    border: 1px solid var(--color-border);
    border-radius: 20px;
    color: var(--color-muted);
    font-size: 12px;
}


@media (max-width: 768px) {

    .applications {
        padding-top: 72px;
        padding-bottom: 72px;
    }

    .application-item h3 {
        font-size: 26px;
    }
}


/* =================================
   11. ABOUT SECTION
================================= */

.about {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: var(--space-xxl) var(--page-padding);

    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 64px;

    border-top: 1px solid var(--color-border);
}

.about-heading h2 {
    font-size: 42px;
    line-height: 1.2;
}

.about-content {
    max-width: 650px;
}

.about-content p {
    color: var(--color-muted);
    font-size: 16px;
    margin-bottom: 20px;
}


@media (max-width: 768px) {

    .about {
        grid-template-columns: 1fr;
        gap: 32px;
        padding-top: 72px;
        padding-bottom: 72px;
    }

    .about-heading h2 {
        font-size: 36px;
    }
}


/* =================================
   12. CONTACT SECTION
================================= */

.contact {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: var(--space-xxl) var(--page-padding);

    text-align: center;
    border-top: 1px solid var(--color-border);
}

.contact h2 {
    font-size: 48px;
    margin-bottom: 20px;
}

.contact-description {
    max-width: 550px;
    margin: 0 auto;
    color: var(--color-muted);
    font-size: 16px;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 32px;
    margin-top: 36px;
}

.contact-links a {
    color: var(--color-accent);
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
    border-bottom: 1px solid var(--color-accent);
    padding-bottom: 4px;
}

.contact-links a:hover {
    color: var(--color-text);
}


@media (max-width: 768px) {

    .contact {
        padding-top: 72px;
        padding-bottom: 72px;
    }

    .contact h2 {
        font-size: 40px;
    }

    .contact-links {
        flex-wrap: wrap;
        gap: 24px;
    }
}


/* =================================
   13. FOOTER
================================= */

.footer {
    border-top: 1px solid var(--color-border);
}

.footer-content {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: 28px var(--page-padding);

    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

.footer-content p {
    color: var(--color-muted);
    font-size: 12px;
}


@media (max-width: 768px) {

    .footer-content {
        flex-direction: column;
        align-items: flex-start;
    }
}