/* ===================================================
   Colby Davis — Personal Landing Page
   External Stylesheet · Vanilla CSS · No frameworks
   =================================================== */

/* --- Google Fonts import is handled via <link> in HTML --- */

/* =====================
   CSS Custom Properties
   ===================== */
:root {
    --bg:          #F8F9FA;
    --text:        #212529;
    --accent:      #1D4ED8;
    --accent-dark: #1741B0;
    --secondary-bg:#E9ECEF;
    --border:      #CED4DA;
    --white:       #FFFFFF;
    --max-width:   800px;
    --section-gap: 60px;
    --radius:      8px;
    --nav-height:  60px;
    --transition:  0.2s ease;
}

/* =====================
   Reset & Base
   ===================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height);
    font-size: 100%;
}

body {
    font-family: 'Inter', sans-serif;
    font-size: 1.1rem;
    line-height: 1.6;
    color: var(--text);
    background-color: var(--bg);
    -webkit-font-smoothing: antialiased;
}

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

ul {
    list-style: none;
}

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

a:hover,
a:focus {
    color: var(--accent-dark);
    text-decoration: underline;
}

a:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 3px;
    border-radius: 3px;
}

h1, h2, h3 {
    line-height: 1.2;
}

h1 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text);
}

h2 {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 1.25rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

h3 {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 0.35rem;
}

p {
    margin-bottom: 0.75rem;
}

p:last-child {
    margin-bottom: 0;
}

/* =====================
   Layout Helpers
   ===================== */
.container {
    max-width: var(--max-width);
    margin-left: auto;
    margin-right: auto;
    padding-left: 1.25rem;
    padding-right: 1.25rem;
}

.section {
    padding-top: var(--section-gap);
    padding-bottom: var(--section-gap);
}

.section-alt {
    background-color: var(--secondary-bg);
}

/* =====================
   Navigation
   ===================== */
.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--white);
    border-bottom: 1px solid var(--border);
    height: var(--nav-height);
    display: flex;
    align-items: center;
}

.nav-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.25rem;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.nav-brand {
    font-weight: 700;
    font-size: 1rem;
    color: var(--text);
    white-space: nowrap;
    text-decoration: none;
}

.nav-brand:hover,
.nav-brand:focus {
    color: var(--accent);
    text-decoration: none;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.nav-links li a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text);
    text-decoration: none;
    transition: color var(--transition);
}

.nav-links li a:hover,
.nav-links li a:focus {
    color: var(--accent);
    text-decoration: none;
}

/* =====================
   Buttons
   ===================== */
.btn {
    display: inline-block;
    padding: 0.65rem 1.4rem;
    border-radius: var(--radius);
    font-size: 0.95rem;
    font-weight: 600;
    font-family: 'Inter', sans-serif;
    cursor: pointer;
    text-decoration: none;
    transition: background-color var(--transition), color var(--transition), border-color var(--transition);
    border: 2px solid transparent;
    line-height: 1.4;
}

.btn:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 3px;
}

.btn-primary {
    background-color: var(--accent);
    color: var(--white);
    border-color: var(--accent);
}

.btn-primary:hover,
.btn-primary:focus {
    background-color: var(--accent-dark);
    border-color: var(--accent-dark);
    color: var(--white);
    text-decoration: none;
}

.btn-secondary {
    background-color: transparent;
    color: var(--accent);
    border-color: var(--accent);
}

.btn-secondary:hover,
.btn-secondary:focus {
    background-color: var(--accent);
    color: var(--white);
    text-decoration: none;
}

/* =====================
   Hero Section
   ===================== */
.hero {
    background-color: var(--white);
}

.hero-inner {
    display: flex;
    align-items: center;
    gap: 2.5rem;
    flex-wrap: wrap;
}

.hero-photo {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    object-fit: cover;
    object-position: top center;
    border: 4px solid var(--secondary-bg);
    flex-shrink: 0;
}

.hero-text {
    flex: 1;
    min-width: 200px;
}

.hero-text h1 {
    margin-bottom: 0.4rem;
}

.hero-tagline {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: 0.3rem;
}

.hero-sub {
    font-size: 0.95rem;
    color: #6C757D;
    margin-bottom: 1.25rem;
}

.hero-ctas {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

/* =====================
   About Me
   ===================== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.about-card {
    background-color: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.25rem 1.5rem;
}

.about-card h3 {
    color: var(--accent);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 0.75rem;
}

.institution {
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.degree {
    font-size: 0.95rem;
    margin-bottom: 0.4rem;
    color: #495057;
}

.detail {
    font-size: 0.9rem;
    color: #6C757D;
    margin-top: 0.5rem;
}

.achievement-list {
    list-style: disc;
    padding-left: 1.2rem;
    margin-bottom: 1rem;
}

.achievement-list li {
    font-size: 0.95rem;
    margin-bottom: 0.3rem;
    color: var(--text);
}

.interests-heading {
    margin-top: 1rem;
}

/* =====================
   Projects Section
   ===================== */
.projects-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.project-card {
    background-color: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.25rem 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.project-header h3 {
    font-size: 1rem;
    flex: 1;
}

.project-date {
    font-size: 0.82rem;
    color: #6C757D;
    white-space: nowrap;
    padding-top: 0.1rem;
}

.project-tools {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.tool-badge {
    background-color: #DBEAFE;
    color: #1E40AF;
    font-size: 0.78rem;
    font-weight: 500;
    padding: 0.2rem 0.65rem;
    border-radius: 999px;
    white-space: nowrap;
}

.project-bullets {
    list-style: disc;
    padding-left: 1.2rem;
    color: #495057;
    font-size: 0.92rem;
}

.project-bullets li {
    margin-bottom: 0.35rem;
}


/* =====================
   Skills Section
   ===================== */
.skills-groups {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.skills-group h3 {
    font-size: 0.9rem;
    font-weight: 600;
    color: #495057;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.65rem;
}

.skill-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skill-badge {
    background-color: var(--white);
    border: 1.5px solid var(--accent);
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 0.35rem 0.9rem;
    border-radius: 999px;
}

/* =====================
   Experience & Leadership
   ===================== */
.experience-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.experience-item {
    background-color: var(--secondary-bg);
    border: 1px solid var(--border);
    border-left: 4px solid var(--accent);
    border-radius: var(--radius);
    padding: 1.25rem 1.5rem;
}

.experience-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-bottom: 0.6rem;
}

.org {
    font-size: 0.9rem;
    color: #6C757D;
    margin-top: 0.15rem;
}

.exp-date {
    font-size: 0.85rem;
    color: #6C757D;
    white-space: nowrap;
    padding-top: 0.15rem;
}

.exp-bullets {
    list-style: disc;
    padding-left: 1.2rem;
    font-size: 0.95rem;
    color: #495057;
}

.exp-bullets li {
    margin-bottom: 0.3rem;
}

/* =====================
   Resume Section
   ===================== */
.resume-section {
    text-align: center;
}

.resume-section p {
    margin-bottom: 1.25rem;
}

/* =====================
   Contact Section
   ===================== */
.contact-links {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.contact-link {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.97rem;
    font-weight: 500;
    color: var(--text);
    text-decoration: none;
    transition: color var(--transition);
}

.contact-link:hover,
.contact-link:focus {
    color: var(--accent);
    text-decoration: none;
}

.contact-icon {
    width: 1.2rem;
    height: 1.2rem;
    flex-shrink: 0;
    stroke: currentColor;
}

/* Contact Form */
.contact-form {
    background-color: var(--secondary-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    max-width: 520px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    margin-bottom: 1rem;
}

.form-group:last-of-type {
    margin-bottom: 1.25rem;
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text);
}

.form-group input,
.form-group textarea {
    font-family: 'Inter', sans-serif;
    font-size: 0.97rem;
    padding: 0.6rem 0.85rem;
    border: 1.5px solid var(--border);
    border-radius: calc(var(--radius) / 2);
    background-color: var(--white);
    color: var(--text);
    transition: border-color var(--transition);
    width: 100%;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(29, 78, 216, 0.15);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* =====================
   Footer
   ===================== */
.footer {
    background-color: var(--text);
    color: #ADB5BD;
    text-align: center;
    padding: 1.25rem 1rem;
    font-size: 0.85rem;
}

/* =====================
   Responsive — Tablet (≤ 680px)
   ===================== */
@media (max-width: 680px) {
    :root {
        --section-gap: 44px;
    }

    h1 {
        font-size: 1.45rem;
    }

    .nav-links {
        gap: 1rem;
    }

    .nav-links li a {
        font-size: 0.82rem;
    }

    .about-grid {
        grid-template-columns: 1fr;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .hero-inner {
        flex-direction: column;
        text-align: center;
    }

    .hero-ctas {
        justify-content: center;
    }

    .experience-header {
        flex-direction: column;
        gap: 0.25rem;
    }

    .project-header {
        flex-direction: column;
    }
}

/* =====================
   Responsive — Mobile (≤ 420px)
   ===================== */
@media (max-width: 420px) {
    :root {
        --section-gap: 36px;
    }

    .nav-links {
        gap: 0.65rem;
    }

    .nav-links li a {
        font-size: 0.78rem;
    }

    .hero-photo {
        width: 130px;
        height: 130px;
    }

    .hero-ctas {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        text-align: center;
    }

    .contact-form {
        padding: 1rem;
    }
}

/* =====================
   Min-width safety (320px)
   ===================== */
@media (max-width: 360px) {
    body {
        font-size: 1rem;
    }

    .nav-inner {
        flex-direction: column;
        height: auto;
        padding-top: 0.5rem;
        padding-bottom: 0.5rem;
        gap: 0.4rem;
    }

    .nav {
        height: auto;
    }

    html {
        scroll-padding-top: 80px;
    }

    .nav-links {
        gap: 0.5rem;
        justify-content: center;
        flex-wrap: wrap;
    }

    .nav-links li a {
        font-size: 0.75rem;
    }
}