/* Siyah mod: ortak tasarım değişkenleri ve açık temadan farklı yüzeyler. */
[data-theme="dark"] {
  --navy: #0a1020;
  --navy-soft: #111c2e;
  --paper: #0e1829;
  --line: #25374e;
  --ink: #e5eef9;
  --muted: #a0b2c8;
  --blue: #8bcdf0;
  --blue-light: #95cdec;
  --page-background: #0a1020;
  --card-background: #121f33;
}
[data-theme="dark"] .site-header { background: #0a1020ed; border-bottom-color: var(--line); }
[data-theme="dark"] .site-header.is-scrolled { background: #0a1020f5; box-shadow: 0 7px 30px #0003; }
[data-theme="dark"] .brand-logo { background: #f4f9ff; border-radius: 6px; }
[data-theme="dark"] .primary-nav { color: #b9cbe0; }
[data-theme="dark"] .primary-nav .nav-contact, [data-theme="dark"] .menu-toggle { border-color: #3b5674; }
[data-theme="dark"] .menu-toggle span { background: #d1e6f5; }
[data-theme="dark"] .hero { background: linear-gradient(120deg, #0a1020, #0d1a2c); }
[data-theme="dark"] .hero::before { opacity: .4; }
[data-theme="dark"] .hero::after { background: radial-gradient(ellipse, #1d5c922e, transparent 65%); }
[data-theme="dark"] .hero .eyebrow { color: #aac9df; }
[data-theme="dark"] .hero h1 > span { background-image: linear-gradient(110deg, #9cccf0 15%, #d7efff 35%, #80c0e6 55%, #a3d9f8 75%); }
[data-theme="dark"] .hero-description, [data-theme="dark"] .hero-footnote { color: #a8bbd1; }
[data-theme="dark"] .hero-visual img { mix-blend-mode: normal; }
[data-theme="dark"] .hero-feature-card { background: #14253ced; border-color: #345373; box-shadow: 0 15px 40px #0003, inset 0 1px 0 #3b56742e; }
[data-theme="dark"] .hero-feature-card p { color: #d2e9fa; }
[data-theme="dark"] .hero-feature-label { color: #8eb5d0; }
[data-theme="dark"] .hero-feature-card .service-icon { background: #1b3550; }
[data-theme="dark"] .hero-motion-control { color: #b3d9ee; background: #172a40e6; border-color: #35546b; }
[data-theme="dark"] .hero-motion-control:hover { background: #29415a; }
[data-theme="dark"] .visual-caption, [data-theme="dark"] .hero-bottom { color: #8fadc5; border-color: var(--line); }
[data-theme="dark"] .hero-bottom > div, [data-theme="dark"] .scroll-link { color: #c0d4e6; }
[data-theme="dark"] .button-outline { color: #cee5f6; border-color: #355670; }
[data-theme="dark"] .button-outline:hover { background: #1a2b40; border-color: #78accd; }
[data-theme="dark"] .button-dark { background: #1d3650; color: #d1e9fa; }
[data-theme="dark"] .button-dark:hover { background: #294966; }
[data-theme="dark"] .service-card, [data-theme="dark"] .product-card, [data-theme="dark"] .portfolio-placeholder { background: var(--card-background); }
[data-theme="dark"] .service-card::before { background: radial-gradient(260px circle at var(--pointer-x, 50%) var(--pointer-y, 0%), #20557a50, transparent 75%); }
[data-theme="dark"] .service-icon { background: #1e354e; color: #9fd3f0; }
[data-theme="dark"] .service-card:hover .service-icon { background: #254563; }
[data-theme="dark"] .service-tags > span { border-color: var(--line); color: #a3bdd3; }
[data-theme="dark"] .service-number, [data-theme="dark"] .step-number, [data-theme="dark"] .pill { color: #97c2df; }
[data-theme="dark"] .about .eyebrow, [data-theme="dark"] .principles span { color: #94b6d2; }
[data-theme="dark"] .about-copy > .lead { color: #e0eafa; }
[data-theme="dark"] .about-copy > p + p, [data-theme="dark"] .principles p { color: #a0b6ce; }
[data-theme="dark"] .principles { border-color: var(--line); }
[data-theme="dark"] .process { background: var(--page-background); }
[data-theme="dark"] .empty-symbol { background: #193048; color: #749cbd; }
[data-theme="dark"] .text-link { color: #98c9e9; }
[data-theme="dark"] .contact { background: linear-gradient(130deg, #0b1423, #13263b); }
[data-theme="dark"] .contact .eyebrow, [data-theme="dark"] .contact-label { color: #92b5d0; }
[data-theme="dark"] .contact-top > div:first-child > p:not(.eyebrow) { color: #a5bad0; }
[data-theme="dark"] .contact-details { border-color: var(--line); }
[data-theme="dark"] .contact-details a { color: #d6e8f8; }
[data-theme="dark"] .contact-details a:hover { color: var(--blue-light); }
[data-theme="dark"] .contact-rule { background: var(--line); }
[data-theme="dark"] .site-footer { background: #0a1020; }
[data-theme="dark"] .footer-main, [data-theme="dark"] .footer-bottom { border-color: var(--line); }
[data-theme="dark"] .footer-main > p, [data-theme="dark"] .footer-bottom, [data-theme="dark"] .back-top { color: #a0b6ce; }
[data-theme="dark"] .skip-link { color: #172b48; }