/* ===========================
   ITSUP.PL — Main Stylesheet
   Static, performant, secure
   =========================== */

/* --- CSS Custom Properties --- */
:root {
    --color-primary: #0f172a;
    --color-primary-light: #1e293b;
    --color-accent: #f97316;
    --color-accent-hover: #ea580c;
    --color-text: #334155;
    --color-text-light: #64748b;
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-border: #e2e8f0;
    --color-surface: #ffffff;

    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', monospace;

    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    --space-4xl: 6rem;

    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;

    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);

    --max-width: 1200px;
    --header-height: 4rem;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
}

body {
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

ul {
    list-style: none;
}

/* --- Utilities --- */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.section__title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--color-primary);
    text-align: center;
    margin-bottom: var(--space-sm);
}

.section__subtitle {
    font-size: 1.125rem;
    color: var(--color-text-light);
    text-align: center;
    margin-bottom: var(--space-3xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.75rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    line-height: 1.4;
}

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

.btn--primary:hover {
    background-color: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
    color: #fff;
}

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

.btn--secondary:hover {
    border-color: var(--color-primary);
    background-color: var(--color-bg-alt);
    color: var(--color-primary);
}

.btn--full {
    width: 100%;
}

/* --- Header --- */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.nav__logo {
    font-size: 1.5rem;
    color: var(--color-primary);
    text-decoration: none;
}

.nav__logo span {
    color: var(--color-accent);
}

.nav__menu {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav__link {
    color: var(--color-text);
    font-weight: 500;
    font-size: 0.9375rem;
    transition: color 0.2s ease;
}

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

.nav__link--cta {
    background-color: var(--color-accent);
    color: #fff;
    padding: 0.5rem 1.25rem;
    border-radius: var(--radius-md);
}

.nav__link--cta:hover {
    background-color: var(--color-accent-hover);
    color: #fff;
}

.nav__toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-sm);
}

.nav__toggle-bar {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-primary);
    border-radius: 2px;
    transition: transform 0.3s ease;
}

/* --- Hero --- */
.hero {
    padding: calc(var(--header-height) + var(--space-4xl)) 0 var(--space-4xl);
    background: linear-gradient(135deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
    text-align: center;
}

.hero__title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    color: var(--color-primary);
    line-height: 1.2;
    margin-bottom: var(--space-lg);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.hero__highlight {
    color: var(--color-accent);
}

.hero__subtitle {
    font-size: clamp(1.0625rem, 2vw, 1.25rem);
    color: var(--color-text-light);
    max-width: 640px;
    margin: 0 auto var(--space-2xl);
    line-height: 1.7;
}

.hero__actions {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* --- Services --- */
.services {
    padding: var(--space-4xl) 0;
}

.services__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--space-xl);
}

.service-card {
    padding: var(--space-2xl);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    background: var(--color-surface);
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.service-card__icon {
    color: var(--color-accent);
    margin-bottom: var(--space-lg);
}

.service-card__title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--space-sm);
}

.service-card__desc {
    color: var(--color-text-light);
    line-height: 1.6;
}

/* --- Technologies --- */
.tech {
    padding: var(--space-4xl) 0;
    background-color: var(--color-bg-alt);
}

.tech__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: var(--space-md);
}

.tech__item {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-lg) var(--space-md);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: border-color 0.2s ease;
}

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

.tech__name {
    font-weight: 600;
    font-size: 0.9375rem;
    color: var(--color-primary);
}

/* --- About --- */
.about {
    padding: var(--space-4xl) 0;
}

.about__content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: start;
}

.about__text p {
    margin-bottom: var(--space-md);
    line-height: 1.7;
}

.about__list {
    margin-top: var(--space-lg);
}

.about__list li {
    position: relative;
    padding-left: var(--space-lg);
    margin-bottom: var(--space-sm);
    color: var(--color-text);
}

.about__list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.6em;
    width: 8px;
    height: 8px;
    background-color: var(--color-accent);
    border-radius: 50%;
}

.about__stats {
    display: grid;
    gap: var(--space-xl);
}

.stat {
    text-align: center;
    padding: var(--space-xl);
    background: var(--color-bg-alt);
    border-radius: var(--radius-lg);
}

.stat__number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--color-accent);
    line-height: 1.2;
}

.stat__label {
    display: block;
    font-size: 0.9375rem;
    color: var(--color-text-light);
    margin-top: var(--space-xs);
}

/* --- Contact --- */
.contact {
    padding: var(--space-4xl) 0;
    background-color: var(--color-bg-alt);
}

.contact__content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: var(--space-3xl);
    align-items: start;
}

.contact__item {
    margin-bottom: var(--space-xl);
}

.contact__item h3 {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-light);
    margin-bottom: var(--space-xs);
}

.contact__item a,
.contact__item p {
    font-size: 1.0625rem;
    color: var(--color-primary);
}

/* --- Form --- */
.form__group {
    margin-bottom: var(--space-lg);
}

.form__label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--space-xs);
}

.form__input {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    font-family: var(--font-sans);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    color: var(--color-text);
    transition: border-color 0.2s ease;
}

.form__input:focus {
    border-color: var(--color-accent);
    outline: none;
    box-shadow: 0 0 0 3px rgba(249, 115, 22, 0.1);
}

.form__textarea {
    resize: vertical;
    min-height: 120px;
}

/* --- Footer --- */
.footer {
    padding: var(--space-2xl) 0;
    background-color: var(--color-primary);
    color: #fff;
}

.footer__content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-xl);
}

.footer__brand {
    font-size: 1.25rem;
}

.footer__brand span {
    color: var(--color-accent);
}

.footer__tagline {
    font-size: 0.875rem;
    color: var(--color-text-light);
    margin-top: var(--space-xs);
}

.footer__nav {
    display: flex;
    gap: var(--space-xl);
}

.footer__nav a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9375rem;
    transition: color 0.2s ease;
}

.footer__nav a:hover {
    color: #fff;
}

.footer__bottom {
    padding-top: var(--space-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.5);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .nav__toggle {
        display: flex;
    }

    .nav__menu {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        background: var(--color-bg);
        flex-direction: column;
        padding: var(--space-xl);
        gap: var(--space-lg);
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: transform 0.3s ease, opacity 0.3s ease;
    }

    .nav__menu.is-active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

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

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

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

    .footer__content {
        flex-direction: column;
        gap: var(--space-lg);
        text-align: center;
    }

    .footer__nav {
        flex-wrap: wrap;
        justify-content: center;
    }

    .hero {
        padding-top: calc(var(--header-height) + var(--space-2xl));
    }
}

@media (max-width: 480px) {
    .tech__grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .btn {
        width: 100%;
        max-width: 280px;
    }
}

/* --- Print --- */
@media print {
    .header,
    .nav__toggle,
    .hero__actions,
    .contact__form {
        display: none;
    }

    body {
        font-size: 12pt;
        color: #000;
    }

    .hero {
        padding-top: 0;
    }
}