/* Bir Alfa - Main Stylesheet */
:root {
    --color-primary: #3E3F43;
    --color-accent: #F2E818;
    --color-white: #FFFFFF;
    --color-off-white: #F8F8F6;
    --color-light-gray: #E8E8E6;
    --color-text: #1A1A1A;
    --color-text-muted: #6B6B6B;
    --font-display: 'Syne', sans-serif;
    --font-body: 'Inter', sans-serif;
    --container-width: 1280px;
    --header-height: 80px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --radius: 4px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-white);
    overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; transition: color var(--transition); }
ul { list-style: none; }

.skip-link {
    position: absolute;
    top: -100%;
    left: 1rem;
    z-index: 9999;
    padding: 0.75rem 1.5rem;
    background: var(--color-accent);
    color: var(--color-primary);
    font-weight: 600;
}
.skip-link:focus { top: 1rem; }

.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 2rem;
}
.container--narrow { max-width: 800px; }

/* Typography */
h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.1;
}

.lead {
    font-size: 1.25rem;
    line-height: 1.7;
    color: var(--color-text-muted);
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 2rem;
    font-family: var(--font-body);
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    border: 2px solid transparent;
    border-radius: var(--radius);
    cursor: pointer;
    transition: all var(--transition);
}
.btn-primary {
    background: var(--color-accent);
    color: var(--color-primary);
    border-color: var(--color-accent);
}
.btn-primary:hover {
    background: transparent;
    color: var(--color-accent);
}
.btn-outline {
    background: transparent;
    color: var(--color-white);
    border-color: var(--color-white);
}
.btn-outline:hover {
    background: var(--color-white);
    color: var(--color-primary);
}
.btn-dark {
    background: var(--color-primary);
    color: var(--color-white);
    border-color: var(--color-primary);
}
.btn-dark:hover {
    background: var(--color-accent);
    color: var(--color-primary);
    border-color: var(--color-accent);
}
.btn-full { width: 100%; }

.link-arrow {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-primary);
}
.link-arrow::after {
    content: '→';
    transition: transform var(--transition);
}
.link-arrow:hover::after { transform: translateX(4px); }

/* Header */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--header-height);
    background: rgba(62, 63, 67, 0.95);
    backdrop-filter: blur(12px);
    transition: background var(--transition);
}
.site-header.is-scrolled {
    background: rgba(62, 63, 67, 0.98);
    box-shadow: 0 2px 20px rgba(0,0,0,0.1);
}

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

.logo-text {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--color-white);
}
.logo-accent { color: var(--color-accent); }

.main-nav { display: flex; }

.nav-list {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    font-size: 0.8125rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: rgba(255,255,255,0.8);
    position: relative;
}
.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-accent);
    transition: width var(--transition);
}
.nav-link:hover,
.nav-link.is-active { color: var(--color-white); }
.nav-link:hover::after,
.nav-link.is-active::after { width: 100%; }

.header-cta { padding: 0.625rem 1.5rem; font-size: 0.75rem; }

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}
.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-white);
    transition: all var(--transition);
}

/* Hero */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: var(--color-primary);
    color: var(--color-white);
    padding-top: var(--header-height);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 80% 20%, rgba(242, 232, 24, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 20% 80%, rgba(242, 232, 24, 0.05) 0%, transparent 40%);
}

.hero-content {
    position: relative;
    z-index: 1;
    padding: 4rem 0;
}

.hero-eyebrow {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    color: var(--color-accent);
    margin-bottom: 1.5rem;
}

.hero-title {
    font-size: clamp(3rem, 8vw, 6.5rem);
    font-weight: 800;
    line-height: 0.95;
    margin-bottom: 2rem;
}
.hero-title .text-accent { display: inline; }

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    max-width: 540px;
    color: rgba(255,255,255,0.7);
    margin-bottom: 2.5rem;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.hero-scroll {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.6875rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: rgba(255,255,255,0.5);
}
.scroll-line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, var(--color-accent), transparent);
    animation: scrollPulse 2s ease-in-out infinite;
}
@keyframes scrollPulse {
    0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
    50% { opacity: 1; transform: scaleY(1); }
}

/* Sections */
.section { padding: 6rem 0; }
.section--dark { background: var(--color-primary); color: var(--color-white); }

.section-header { margin-bottom: 4rem; max-width: 600px; }
.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 1rem;
}
.section-title--center { text-align: center; margin: 0 auto 3rem; }
.section-desc { color: var(--color-text-muted); font-size: 1.125rem; }
.section-cta { text-align: center; margin-top: 3rem; }

/* Split Layout */
.split-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}
.split-content p { margin-bottom: 1.25rem; color: var(--color-text-muted); }
.split-content .lead { color: var(--color-text); margin-bottom: 1.5rem; }

.visual-block {
    background: var(--color-primary);
    color: var(--color-white);
    padding: 4rem;
    border-radius: var(--radius);
    position: relative;
    overflow: hidden;
}
.visual-block::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -30%;
    width: 200px;
    height: 200px;
    background: var(--color-accent);
    opacity: 0.1;
    border-radius: 50%;
}
.visual-number {
    font-family: var(--font-display);
    font-size: 5rem;
    font-weight: 800;
    color: var(--color-accent);
    display: block;
    margin-bottom: 1.5rem;
    line-height: 1;
}
.visual-block p { font-size: 1.25rem; line-height: 1.6; position: relative; }
.visual-block strong { color: var(--color-accent); }

/* Services Grid */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}
.services-grid--full { grid-template-columns: repeat(2, 1fr); }

.service-card {
    padding: 2.5rem;
    background: var(--color-off-white);
    border-radius: var(--radius);
    transition: all var(--transition);
    border: 1px solid transparent;
}
.service-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(62, 63, 67, 0.08);
}
.service-icon {
    font-family: var(--font-display);
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--color-accent);
    background: var(--color-primary);
    display: inline-block;
    padding: 0.375rem 0.75rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
}
.service-title {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}
.service-card p { color: var(--color-text-muted); font-size: 0.9375rem; }

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}
.projects-grid--full { grid-template-columns: repeat(2, 1fr); }

.project-card {
    aspect-ratio: 4/3;
    background: var(--color-primary);
    border-radius: var(--radius);
    overflow: hidden;
    cursor: pointer;
    transition: all var(--transition);
}
.project-card:hover { transform: scale(1.02); }
.project-card--large { aspect-ratio: 16/10; }

.project-card-inner {
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 2rem;
    background: linear-gradient(to top, rgba(0,0,0,0.7) 0%, transparent 60%);
    color: var(--color-white);
    transition: background var(--transition);
}
.project-card:hover .project-card-inner {
    background: linear-gradient(to top, rgba(62,63,67,0.95) 0%, rgba(242,232,24,0.15) 100%);
}
.project-category {
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-accent);
    margin-bottom: 0.5rem;
}
.project-title {
    font-size: 1.375rem;
    font-weight: 700;
}

/* Marquee */
.marquee {
    overflow: hidden;
    padding: 2rem 0;
    background: var(--color-off-white);
    border-top: 1px solid var(--color-light-gray);
    border-bottom: 1px solid var(--color-light-gray);
}
.marquee-track {
    display: flex;
    gap: 4rem;
    animation: marquee 30s linear infinite;
    width: max-content;
}
.marquee-item {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    white-space: nowrap;
    opacity: 0.6;
    transition: opacity var(--transition);
}
.marquee-item:hover { opacity: 1; }
@keyframes marquee {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* CTA Banner */
.cta-banner {
    background: var(--color-accent);
    color: var(--color-primary);
    padding: 4rem;
    border-radius: var(--radius);
    text-align: center;
}
.cta-title {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 1rem;
}
.cta-banner p {
    font-size: 1.125rem;
    margin-bottom: 2rem;
    opacity: 0.8;
}

/* Page Hero */
.page-hero {
    background: var(--color-primary);
    color: var(--color-white);
    padding: calc(var(--header-height) + 4rem) 0 4rem;
}
.page-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
}
.page-subtitle {
    font-size: 1.125rem;
    color: rgba(255,255,255,0.7);
    margin-top: 1rem;
    max-width: 500px;
}

/* Prose */
.prose p { margin-bottom: 1.25rem; color: var(--color-text-muted); line-height: 1.8; }
.prose--center { text-align: center; }
.quote-block {
    margin: 3rem 0;
    padding: 2.5rem;
    background: var(--color-off-white);
    border-left: 4px solid var(--color-accent);
    border-radius: 0 var(--radius) var(--radius) 0;
}
.quote-block p {
    font-family: var(--font-display);
    font-size: 1.375rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 1rem;
}
.quote-block cite {
    font-style: normal;
    font-size: 0.9375rem;
    color: var(--color-text-muted);
}

/* References Grid */
.references-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
}
.reference-card {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 3rem 2rem;
    background: var(--color-off-white);
    border-radius: var(--radius);
    border: 1px solid var(--color-light-gray);
    transition: all var(--transition);
}
.reference-card:hover {
    border-color: var(--color-accent);
    background: var(--color-white);
    transform: translateY(-2px);
}
.reference-name {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-primary);
    text-align: center;
}

/* Blog */
.blog-grid { display: flex; flex-direction: column; gap: 2rem; }
.blog-card {
    padding: 2.5rem;
    background: var(--color-off-white);
    border-radius: var(--radius);
    border: 1px solid transparent;
    transition: all var(--transition);
}
.blog-card:hover {
    border-color: var(--color-accent);
    transform: translateX(4px);
}
.blog-date {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-accent);
    background: var(--color-primary);
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius);
    margin-bottom: 1rem;
}
.blog-title {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
}
.blog-excerpt { color: var(--color-text-muted); }

/* Contact */
.contact-layout {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 4rem;
    align-items: start;
}
.contact-info h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
}
.contact-info > p {
    color: var(--color-text-muted);
    margin-bottom: 2rem;
    line-height: 1.7;
}
.contact-details li {
    margin-bottom: 1.5rem;
}
.contact-details strong {
    display: block;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-text-muted);
    margin-bottom: 0.25rem;
}
.contact-details a:hover { color: var(--color-accent); }

.contact-form-wrap {
    background: var(--color-off-white);
    padding: 2.5rem;
    border-radius: var(--radius);
}
.form-group { margin-bottom: 1.5rem; }
.form-group label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    font-family: var(--font-body);
    font-size: 1rem;
    border: 1px solid var(--color-light-gray);
    border-radius: var(--radius);
    background: var(--color-white);
    transition: border-color var(--transition);
}
.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-accent);
}
.form-group textarea { resize: vertical; min-height: 120px; }

.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    font-size: 0.9375rem;
}
.alert-success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}
.alert-error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* Footer */
.site-footer {
    background: var(--color-primary);
    color: var(--color-white);
    padding: 4rem 0 2rem;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}
.footer-tagline {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 600;
    margin: 1rem 0 0.5rem;
}
.footer-desc { color: rgba(255,255,255,0.5); font-size: 0.9375rem; }
.footer-heading {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-accent);
    margin-bottom: 1.25rem;
}
.footer-nav ul li,
.footer-contact ul li { margin-bottom: 0.625rem; }
.footer-nav a,
.footer-contact a {
    color: rgba(255,255,255,0.7);
    font-size: 0.9375rem;
}
.footer-nav a:hover,
.footer-contact a:hover { color: var(--color-accent); }
.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 0.8125rem;
    color: rgba(255,255,255,0.4);
}

/* Reveal Animation */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
    transition-delay: var(--delay, 0s);
}
.reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 1024px) {
    .services-grid,
    .projects-grid { grid-template-columns: repeat(2, 1fr); }
    .references-grid { grid-template-columns: repeat(3, 1fr); }
    .split-layout { grid-template-columns: 1fr; gap: 2rem; }
    .contact-layout { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .main-nav {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        bottom: 0;
        background: var(--color-primary);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transform: translateX(100%);
        transition: transform var(--transition);
    }
    .main-nav.is-open { transform: translateX(0); }
    .nav-list { flex-direction: column; gap: 2rem; }
    .nav-link { font-size: 1.25rem; }
    .header-cta { display: none; }
    .menu-toggle { display: flex; }
    .menu-toggle.is-active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
    .menu-toggle.is-active span:nth-child(2) { opacity: 0; }
    .menu-toggle.is-active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

    .services-grid,
    .services-grid--full,
    .projects-grid,
    .projects-grid--full { grid-template-columns: 1fr; }
    .references-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr; }
    .section { padding: 4rem 0; }
    .cta-banner { padding: 2.5rem 1.5rem; }
    .visual-block { padding: 2.5rem; }
}

/* Error Page (404 within site layout) */
.error-page {
    display: grid;
    grid-template-columns: minmax(240px, 38%) 1fr;
    min-height: calc(100vh - var(--header-height));
}

.error-page__panel {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-primary);
    overflow: hidden;
}

.error-page__panel::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    background: var(--color-accent);
}

.error-page__panel::after {
    content: '';
    position: absolute;
    right: -25%;
    bottom: -25%;
    width: 80%;
    aspect-ratio: 1;
    background: var(--color-accent);
    opacity: 0.08;
    border-radius: 50%;
}

.error-page__code {
    position: relative;
    z-index: 1;
    font-family: var(--font-display);
    font-size: clamp(5rem, 14vw, 9rem);
    font-weight: 800;
    line-height: 0.9;
    letter-spacing: -0.05em;
    color: var(--color-accent);
}

.error-page__body {
    display: flex;
    align-items: center;
    padding: clamp(3rem, 8vw, 6rem) 0;
    background: var(--color-white);
}

.error-page__eyebrow {
    display: inline-block;
    margin-bottom: 1rem;
    padding: 0.35rem 0.75rem;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-primary);
    background: rgba(242, 232, 24, 0.35);
    border-radius: 2px;
}

.error-page__title {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 1rem;
    color: var(--color-primary);
    letter-spacing: -0.03em;
}

.error-page__text {
    font-size: 1.0625rem;
    color: var(--color-text-muted);
    margin-bottom: 2.5rem;
    line-height: 1.75;
    max-width: 460px;
}

.error-page__actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

@media (max-width: 768px) {
    .error-page {
        grid-template-columns: 1fr;
        grid-template-rows: 200px 1fr;
    }

    .error-page__body {
        padding: 2.5rem 0 4rem;
    }

    .error-page__actions {
        flex-direction: column;
        align-items: stretch;
    }

    .error-page__actions .btn {
        width: 100%;
    }
}