/* ========================================
   GLOBAL VARIABLES
======================================== */

:root {
    --background: #0d1117;
    --surface: #161b22;
    --surface-light: #21262d;
    --text: #f0f6fc;
    --muted-text: #b7c0ca;
    --accent: #62e6d3;
    --accent-dark: #143f3b;
    --border: #46515d;
    --danger: #ffb4ab;
    --maximum-width: 1120px;
    --border-radius: 14px;
}


/* ========================================
   RESET AND BASE STYLES
======================================== */

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 90px;
}

body {
    margin: 0;
    background-color: var(--background);
    color: var(--text);
    font-family: Arial, Helvetica, sans-serif;
    font-size: 1rem;
    line-height: 1.7;
}

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

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

a:hover {
    text-decoration-thickness: 3px;
}

button,
input,
select {
    font: inherit;
}

button,
a {
    -webkit-tap-highlight-color: transparent;
}


/* ========================================
   ACCESSIBILITY
======================================== */

.skip-link {
    position: absolute;
    top: -100px;
    left: 1rem;
    z-index: 1000;
    padding: 0.75rem 1rem;
    background-color: var(--accent);
    color: #07110f;
    font-weight: bold;
    border-radius: 0 0 8px 8px;
}

.skip-link:focus {
    top: 0;
}

a:focus-visible,
button:focus-visible,
input:focus-visible {
    outline: 4px solid white;
    outline-offset: 4px;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible {
    outline: 4px solid white;
    outline-offset: 4px;
}

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


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

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: rgba(13, 17, 23, 0.96);
    border-bottom: 1px solid var(--border);
}

.navigation {
    width: min(100% - 2rem, var(--maximum-width));
    min-height: 72px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

.site-name {
    color: var(--text);
    font-size: 1.2rem;
    font-weight: bold;
    text-decoration: none;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin: 0;
    padding: 0;
    list-style: none;
}

.nav-links a {
    display: inline-block;
    min-height: 44px;
    padding: 0.55rem 0.25rem;
    color: var(--text);
    font-weight: bold;
    text-decoration: none;
    border-bottom: 3px solid transparent;
}

.nav-links a:hover,
.nav-links a:focus-visible {
    color: var(--accent);
    border-bottom-color: var(--accent);
}


/* ========================================
   HERO
======================================== */

.hero {
    padding: clamp(4rem, 9vw, 8rem) 1rem;
    background:
        linear-gradient(
            135deg,
            var(--background) 0%,
            var(--surface) 55%,
            var(--accent-dark) 100%
        );
}

.hero-content {
    width: min(100%, var(--maximum-width));
    margin: 0 auto;
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(260px, 0.75fr);
    align-items: center;
    gap: clamp(2rem, 6vw, 5rem);
}

.eyebrow,
.section-label {
    margin: 0 0 0.5rem;
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: bold;
    letter-spacing: 0.13em;
    text-transform: uppercase;
}

.hero h1 {
    margin: 0;
    font-size: clamp(3rem, 8vw, 6rem);
    line-height: 1;
    letter-spacing: -0.05em;
}

.hero-introduction {
    max-width: 650px;
    margin: 1.5rem 0 0;
    color: var(--muted-text);
    font-size: clamp(1.15rem, 2vw, 1.4rem);
}

.profile-image {
    width: min(100%, 390px);
    aspect-ratio: 4 / 5;
    margin: 0 auto;
    object-fit: cover;
    border: 4px solid var(--accent);
    border-radius: 24px;
    box-shadow: 18px 18px 0 var(--accent-dark);
}


/* ========================================
   BUTTONS AND LINKS
======================================== */

.hero-buttons,
.contact-links {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 2rem;
}

.button {
    min-height: 48px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.8rem 1.25rem;
    border: 2px solid transparent;
    border-radius: 8px;
    font-weight: bold;
    line-height: 1.2;
    text-align: center;
    text-decoration: none;
    cursor: pointer;
    transition:
        transform 150ms ease,
        background-color 150ms ease,
        border-color 150ms ease;
}

.button:hover {
    transform: translateY(-2px);
}

.primary-button {
    background-color: var(--accent);
    color: #07110f;
}

.primary-button:hover {
    background-color: #91f3e5;
}

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

.secondary-button:hover {
    background-color: var(--accent-dark);
}

.reset-button {
    background-color: transparent;
    color: var(--text);
    border-color: var(--border);
}

.reset-button:hover {
    background-color: var(--surface-light);
}

.text-link {
    font-weight: bold;
    text-underline-offset: 0.3em;
}


/* ========================================
   GENERAL SECTIONS
======================================== */

.section {
    padding: clamp(4rem, 8vw, 7rem) 1rem;
}

.alternate-section {
    background-color: var(--surface);
}

.section-content {
    width: min(100%, var(--maximum-width));
    margin: 0 auto;
}

.narrow-content {
    max-width: 800px;
}

.section h2 {
    max-width: 850px;
    margin: 0;
    font-size: clamp(2rem, 5vw, 3.5rem);
    line-height: 1.15;
    letter-spacing: -0.03em;
}

.section h3 {
    line-height: 1.3;
}

.section-content > p:not(.section-label) {
    color: var(--muted-text);
}

.section-introduction {
    max-width: 760px;
    margin: 1rem 0 2.5rem;
    font-size: 1.1rem;
}


/* ========================================
   PROJECT CARDS
======================================== */

.project-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.5rem;
}

.project-card {
    display: flex;
    flex-direction: column;
    padding: 1.75rem;
    background-color: var(--background);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
}

.project-card:hover {
    border-color: var(--accent);
}

.project-number {
    color: var(--accent);
    font-size: 1rem;
    font-weight: bold;
}

.project-card h3 {
    margin: 1rem 0 0.75rem;
    font-size: 1.4rem;
}

.project-card p {
    flex-grow: 1;
    color: var(--muted-text);
}


/* ========================================
   CALCULATOR
======================================== */

.calculator-layout {
    display: grid;
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    gap: 2rem;
    align-items: start;
}

.instructions-panel,
.calculator-form,
.results-panel,
.counter-card {
    padding: clamp(1.5rem, 4vw, 2.5rem);
    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
}

.instructions-panel h3,
.results-panel h3 {
    margin-top: 0;
}

.results-header {
    display: flex;
    align-items: center;
}

.results-header h3 {
    margin: 0;
}

.results-header h2 {
    flex: 1;
    margin: 0;
    text-align: center;
    color: yellowgreen;
    font-size: 1.8rem;
    font-weight: 600;
}

.instructions-list {
    padding-left: 1.4rem;
}

.instructions-list li {
    margin-bottom: 1rem;
}

.form-group {
    margin-bottom: 1.4rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.3rem;
    color: var(--text);
    font-weight: bold;
}

.help-text {
    display: block;
    margin-bottom: 0.55rem;
    color: var(--muted-text);
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    min-height: 48px;
    padding: 0.7rem 0.8rem;
    background-color: var(--background);
    color: var(--text);
    border: 2px solid var(--border);
    border-radius: 7px;
}

.form-group input:hover {
    border-color: var(--accent);
}

.calculator-form .button {
    margin: 0.5rem 0.5rem 0 0;
}

.form-message {
    min-height: 1.7em;
    margin-bottom: 0;
    color: var(--danger);
    font-weight: bold;
}

.results-panel {
    margin-top: 2rem;
    border-color: var(--accent);
}

.result-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1rem;
}

.result-item {
    padding: 1.25rem;
    background-color: var(--background);
    border-radius: 10px;
}

.result-label {
    display: block;
    color: var(--muted-text);
}

.result-item strong {
    display: block;
    margin-top: 0.3rem;
    color: var(--accent);
    font-size: clamp(1.8rem, 4vw, 2.5rem);
}

.results-disclaimer {
    margin-bottom: 0;
    color: var(--muted-text);
    font-size: 0.9rem;
}

.exercise-section {
    margin-top: 2rem;
    padding: clamp(1.5rem, 4vw, 2rem);
    background-color: var(--background);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
}

.exercise-section legend {
    padding: 0 0.5rem;
    color: var(--accent);
    font-size: 1.3rem;
    font-weight: bold;
}

.exercise-entry {
    display: grid;
    grid-template-columns: 2fr 1fr auto;
    gap: 1rem;
    align-items: end;

    margin-top: 1rem;
    padding: 1rem;

    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
}

.exercise-input-group label {
    display: block;
    margin-bottom: 0.3rem;

    color: var(--text);
    font-weight: bold;
}

.exercise-entry select,
.exercise-entry input {
    width: 100%;
    min-height: 48px;

    padding: 0.7rem 0.8rem;

    background-color: var(--background);
    color: var(--text);

    border: 2px solid var(--border);
    border-radius: 7px;
}

.exercise-entry select:hover,
.exercise-entry input:hover {
    border-color: var(--accent);
}

.remove-exercise {
    min-height: 48px;
    padding: 0.7rem 1rem;

    background-color: transparent;
    color: var(--danger);

    border: 2px solid var(--danger);
    border-radius: 7px;

    cursor: pointer;
    transition: 0.2s;
}

.remove-exercise:hover {
    background-color: var(--danger);
    color: white;
}


/* ========================================
   COUNTER
======================================== */

.counter-card {
    margin-top: 2rem;
    text-align: center;
}

#countLabel {
    display: block;
    color: var(--accent);
    font-size: clamp(4rem, 12vw, 7rem);
    font-weight: bold;
    line-height: 1.1;
}

.counter-buttons {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.counter-button {
    background-color: var(--accent);
    color: #07110f;
}


/* ========================================
   CONTACT AND FOOTER
======================================== */

.contact-section {
    text-align: center;
}

.contact-section h2 {
    margin-right: auto;
    margin-left: auto;
}

.contact-section p {
    max-width: 680px;
    margin-right: auto;
    margin-left: auto;
}

.contact-links {
    justify-content: center;
}

.site-footer {
    padding: 2rem 1rem;
    background-color: var(--surface);
    color: var(--muted-text);
    text-align: center;
    border-top: 1px solid var(--border);
}

.site-footer p {
    margin: 0 0 0.4rem;
}


/* ========================================
   TABLET LAYOUT
======================================== */

@media only screen and (max-width: 900px) {
    .hero-content {
        grid-template-columns: 1fr;
    }

    .hero-text {
        text-align: center;
    }

    .hero-introduction {
        margin-right: auto;
        margin-left: auto;
    }

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

    .profile-image {
        width: min(75%, 360px);
        grid-row: 1;
    }

    .project-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .project-card:last-child {
        grid-column: 1 / -1;
    }

    .calculator-layout {
        grid-template-columns: 1fr;
    }
}


/* ========================================
   MOBILE LAYOUT
======================================== */

@media only screen and (max-width: 600px) {
    html {
        scroll-padding-top: 150px;
    }

    .navigation {
        min-height: auto;
        padding: 0.8rem 0;
        flex-direction: column;
        gap: 0.5rem;
    }

    .nav-links {
        width: 100%;
        justify-content: space-between;
        gap: 0.35rem;
    }

    .nav-links a {
        padding: 0.55rem 0.2rem;
        font-size: 0.88rem;
    }

    .hero {
        padding-top: 3rem;
    }

    .hero h1 {
        font-size: clamp(2.7rem, 15vw, 4rem);
    }

    .profile-image {
        width: min(85%, 320px);
        box-shadow: 10px 10px 0 var(--accent-dark);
    }

    .hero-buttons,
    .contact-links {
        flex-direction: column;
    }

    .hero-buttons .button,
    .contact-links .button {
        width: 100%;
    }

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

    .project-card:last-child {
        grid-column: auto;
    }

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

    .calculator-form .button {
        width: 100%;
        margin-right: 0;
    }

    .counter-buttons {
        flex-direction: column;
    }

    .counter-buttons .button {
        width: 100%;
    }

    .exercise-entry {
        grid-template-columns: 1fr;
    }

    .remove-exercise {
        width: 100%;
    }
}


/* ========================================
   REDUCED MOTION
======================================== */

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        transition-duration: 0.01ms !important;
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
    }
}