/* ==========================================================================
   BT-MS — Biyoteknoloji ve Multipl Skleroz Araştırma Derneği
   Temiz, kurumsal tasarım. Degrade yok. Tek yazı tipi: Poppins.
   ========================================================================== */

:root {
  /* Marka renkleri (logodan) */
  --ink:         #20242a;   /* ana metin */
  --ink-soft:    #4b525a;   /* ikincil metin */
  --gray:        #6b7178;   /* logo grisi */
  --orange:      #f39200;   /* logo turuncusu */
  --orange-dark: #d77f00;
  --orange-soft: #fff4e3;   /* açık turuncu zemin */

  --bg:          #ffffff;
  --bg-soft:     #f6f7f8;   /* açık gri bölüm zemini */
  --line:        #e6e8eb;   /* ince çizgiler */
  --line-strong: #d4d8dc;

  --maxw: 1180px;
  --radius: 10px;
  --shadow-sm: 0 1px 2px rgba(32, 36, 42, .06);
  --shadow:    0 8px 30px rgba(32, 36, 42, .08);

  --ease: cubic-bezier(.22, .61, .36, 1);
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
/* clip: yatay taşmayı keser ama 'hidden'ın aksine sticky'yi bozmaz */
html, body { overflow-x: clip; }

body {
  font-family: "Poppins", system-ui, -apple-system, Segoe UI, sans-serif;
  font-weight: 400;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  font-size: 16.5px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

h1, h2, h3, h4 { font-weight: 600; line-height: 1.2; letter-spacing: -.01em; color: var(--ink); overflow-wrap: break-word; }
h2 { font-size: clamp(1.7rem, 3.4vw, 2.5rem); }
h3 { font-size: 1.2rem; font-weight: 600; }
p  { color: var(--ink-soft); }

.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 22px; }

/* Genel yardımcılar ------------------------------------------------------- */
.section { padding: clamp(56px, 8vw, 104px) 0; }
.section--soft { background: var(--bg-soft); }

.eyebrow {
  display: block;
  font-size: .8rem; font-weight: 600; letter-spacing: .14em; text-transform: uppercase;
  color: var(--orange-dark); line-height: 1.5;
}
.eyebrow::before {
  content: ""; width: 26px; height: 2px; background: var(--orange);
  display: inline-block; vertical-align: middle; margin-right: 9px;
}

.section-head { max-width: 680px; margin-bottom: 48px; }
.section-head.center { margin-inline: auto; text-align: center; }
.section-head.center .eyebrow::before { display: none; }
.section-head p { margin-top: 14px; font-size: 1.05rem; }

/* Butonlar ---------------------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  font-weight: 500; font-size: .98rem;
  padding: 13px 26px; border-radius: 8px; border: 1.5px solid transparent;
  cursor: pointer; transition: all .22s var(--ease);
  white-space: nowrap;
}
.btn .mdi { font-size: 1.2em; }
.btn-primary { background: var(--orange); color: #fff; }
.btn-primary:hover { background: var(--orange-dark); transform: translateY(-2px); box-shadow: 0 10px 24px rgba(243,146,0,.28); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line-strong); }
.btn-ghost:hover { border-color: var(--ink); transform: translateY(-2px); }
.btn-light { background: #fff; color: var(--ink); }
.btn-light:hover { transform: translateY(-2px); box-shadow: var(--shadow); }

/* ==========================================================================
   NAVBAR
   ========================================================================== */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .25s var(--ease), background .25s var(--ease);
}
.nav.scrolled { background: rgba(255,255,255,.97); box-shadow: 0 6px 24px rgba(32,36,42,.08); }
.nav__inner { display: flex; align-items: center; justify-content: space-between; height: 76px; }

.brand { display: flex; align-items: center; gap: 12px; }
.brand__mark {
  font-weight: 700; font-size: 1.5rem; letter-spacing: -.02em; line-height: 1;
}
.brand__mark .g { color: var(--gray); }
.brand__mark .o { color: var(--orange); }
.brand__name {
  font-size: .72rem; font-weight: 500; color: var(--ink-soft);
  line-height: 1.25; max-width: 200px; letter-spacing: .01em;
  border-left: 1px solid var(--line-strong); padding-left: 12px;
}

.nav__menu { display: flex; align-items: center; gap: 2px; list-style: none; }
.nav__menu a {
  display: block; padding: 9px 12px; border-radius: 7px; white-space: nowrap;
  font-size: .94rem; font-weight: 500; color: var(--ink-soft);
  transition: color .18s, background .18s;
}
.nav__menu a:hover { color: var(--ink); background: var(--bg-soft); }
.nav__menu a.active { color: var(--orange-dark); }

.nav__cta { margin-left: 10px; }

.nav__toggle {
  display: none; width: 44px; height: 44px; border: 1px solid var(--line);
  background: #fff; border-radius: 8px; cursor: pointer; align-items: center; justify-content: center;
}
.nav__toggle span, .nav__toggle span::before, .nav__toggle span::after {
  content: ""; display: block; width: 20px; height: 2px; background: var(--ink); position: relative;
  transition: transform .25s var(--ease), opacity .2s;
}
.nav__toggle span::before { position: absolute; top: -6px; }
.nav__toggle span::after  { position: absolute; top: 6px; }
.nav.open .nav__toggle span { background: transparent; }
.nav.open .nav__toggle span::before { transform: translateY(6px) rotate(45deg); }
.nav.open .nav__toggle span::after  { transform: translateY(-6px) rotate(-45deg); }

/* ==========================================================================
   HERO / SLIDER
   ========================================================================== */
.hero { position: relative; background: var(--bg-soft); overflow: hidden; }
.slider { position: relative; }
.slide {
  position: absolute; inset: 0; opacity: 0; visibility: hidden;
  transition: opacity .7s var(--ease);
  display: grid; align-items: center;
}
.slide.is-active { position: relative; opacity: 1; visibility: visible; }

.slide__inner {
  display: grid; grid-template-columns: 1.15fr .85fr; gap: 50px; align-items: center;
  padding: clamp(54px, 7vw, 96px) 0;
}
.slide__text { max-width: 600px; min-width: 0; }
.slide__text .eyebrow { margin-bottom: 18px; }
.slide__text h1 {
  font-size: clamp(2.1rem, 4.6vw, 3.35rem); font-weight: 700; line-height: 1.1;
  letter-spacing: -.02em;
}
.slide__text h1 .accent { color: var(--orange); }
.slide__text p { margin-top: 20px; font-size: 1.12rem; max-width: 520px; }
.slide__actions { margin-top: 32px; display: flex; gap: 14px; flex-wrap: wrap; }

/* Sağ taraf — flat geometrik görsel (degrade yok) */
.slide__visual {
  position: relative; aspect-ratio: 1/1; max-width: 420px; justify-self: end; width: 100%;
}
.slide__visual .ring {
  position: absolute; inset: 0; border-radius: 50%;
  border: 1.5px solid var(--line-strong);
}
.slide__visual .ring--2 { inset: 16%; border-style: dashed; }
.slide__visual .disc {
  position: absolute; inset: 30%; border-radius: 50%;
  background: #fff; box-shadow: var(--shadow);
  display: grid; place-items: center;
}
.slide__visual .disc .mdi { font-size: 4.4rem; color: var(--orange); }
.slide__visual .dot {
  position: absolute; width: 16px; height: 16px; border-radius: 50%; background: var(--orange);
}
.slide__visual .dot--a { top: 6%; left: 46%; }
.slide__visual .dot--b { bottom: 10%; right: 8%; width: 11px; height: 11px; background: var(--gray); }
.slide__visual .dot--c { top: 40%; left: -2%; width: 9px; height: 9px; background: var(--gray); }

/* Slider kontrolleri */
.slider__nav {
  position: absolute; bottom: 28px; left: 50%; transform: translateX(-50%);
  display: flex; gap: 10px; z-index: 5;
}
.slider__dot {
  width: 11px; height: 11px; border-radius: 50%; border: 0; cursor: pointer; padding: 0;
  background: var(--line-strong); transition: all .25s var(--ease);
}
.slider__dot.is-active { background: var(--orange); width: 30px; border-radius: 6px; }

.slider__arrow {
  position: absolute; top: 50%; transform: translateY(-50%); z-index: 5;
  width: 46px; height: 46px; border-radius: 50%; border: 1px solid var(--line);
  background: rgba(255,255,255,.9); cursor: pointer; display: grid; place-items: center;
  color: var(--ink); transition: all .2s var(--ease);
}
.slider__arrow:hover { background: #fff; box-shadow: var(--shadow); color: var(--orange-dark); }
.slider__arrow .mdi { font-size: 1.5rem; }
.slider__arrow--prev { left: 18px; }
.slider__arrow--next { right: 18px; }

/* ==========================================================================
   İSTATİSTİK ŞERİDİ
   ========================================================================== */
.stats { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: #fff; }
.stats__grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { padding: 38px 24px; text-align: center; border-left: 1px solid var(--line); min-width: 0; }
.stat:first-child { border-left: 0; }
.stat__num { font-size: 2.3rem; font-weight: 700; color: var(--ink); letter-spacing: -.02em; }
.stat__num .u { color: var(--orange); }
.stat__label { font-size: .9rem; color: var(--ink-soft); margin-top: 4px; }

/* ==========================================================================
   HAKKIMIZDA (özet)
   ========================================================================== */
.about { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.about__media {
  position: relative; aspect-ratio: 4/3; border-radius: var(--radius);
  background: var(--bg-soft); border: 1px solid var(--line);
  display: grid; place-items: center; overflow: hidden;
}
.about__media .mdi { font-size: 6rem; color: var(--line-strong); }
.about__media .tag {
  position: absolute; left: 22px; bottom: 22px; background: #fff;
  border: 1px solid var(--line); border-radius: 8px; padding: 12px 16px;
  box-shadow: var(--shadow-sm); font-size: .85rem; color: var(--ink-soft);
}
.about__media .tag strong { color: var(--ink); display: block; font-size: 1rem; }
.about p + p { margin-top: 14px; }
.about__list { list-style: none; margin-top: 24px; display: grid; gap: 12px; }
.about__list li { display: flex; gap: 12px; align-items: flex-start; color: var(--ink-soft); }
.about__list .mdi { color: var(--orange); font-size: 1.3rem; flex: none; margin-top: 1px; }

/* ==========================================================================
   KART IZGARALARI (amaçlar / faaliyet alanları)
   ========================================================================== */
.grid-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }

.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 32px 28px; transition: transform .25s var(--ease), box-shadow .25s var(--ease), border-color .25s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--line-strong); }
.card__icon {
  width: 52px; height: 52px; border-radius: 12px; background: var(--orange-soft);
  display: grid; place-items: center; margin-bottom: 20px;
}
.card__icon .mdi { font-size: 1.7rem; color: var(--orange-dark); }
.card h3 { margin-bottom: 8px; }
.card p { font-size: .96rem; }

/* Yönetim kurulu üye kartları — ortalı, son satır da merkezde */
.board-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 22px; }
.member {
  flex: 0 1 320px; max-width: 340px;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 32px 24px; text-align: center;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease), border-color .25s;
}
.member:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--line-strong); }
.member__avatar {
  width: 116px; height: 116px; margin: 0 auto 18px; border-radius: 50%;
  background: var(--orange-soft); color: var(--orange-dark);
  display: grid; place-items: center; font-size: 2.1rem; font-weight: 600; letter-spacing: .02em;
  border: 3px solid #f6e2c2;
}
.member__photo {
  width: 116px; height: 116px; margin: 0 auto 18px; border-radius: 50%;
  overflow: hidden; border: 3px solid var(--orange-soft); background: var(--orange-soft);
}
.member__photo img { width: 100%; height: 100%; object-fit: cover; display: block; }
.member__name { font-size: 1.12rem; font-weight: 600; color: var(--ink); }
.member__role {
  display: inline-block; margin-top: 8px; font-size: .82rem; font-weight: 500;
  color: var(--orange-dark); background: var(--orange-soft); padding: 5px 12px; border-radius: 20px;
}
.member--lead { border-color: var(--orange); }
.member--lead .member__avatar { background: var(--orange); color: #fff; border-color: var(--orange); }
.member--lead .member__photo { border-color: var(--orange); }

/* numaralı sade liste (faaliyet alanları) */
.feature {
  display: flex; gap: 20px; padding: 26px 0; border-bottom: 1px solid var(--line);
}
.feature:last-child { border-bottom: 0; }
.feature__no { font-size: 1.05rem; font-weight: 700; color: var(--orange); flex: none; width: 38px; }
.feature h3 { font-size: 1.08rem; }
.feature p { font-size: .95rem; margin-top: 4px; }

/* ==========================================================================
   ÇAĞRI (CTA) BANDI
   ========================================================================== */
.cta-band { background: var(--ink); color: #fff; border-radius: 16px; padding: clamp(40px, 6vw, 64px); }
.cta-band__inner { display: flex; align-items: center; justify-content: space-between; gap: 40px; flex-wrap: wrap; }
.cta-band h2 { color: #fff; max-width: 620px; }
.cta-band p { color: rgba(255,255,255,.72); margin-top: 12px; max-width: 560px; }
.cta-band .btn-ghost { color: #fff; border-color: rgba(255,255,255,.4); }
.cta-band .btn-ghost:hover { border-color: #fff; }

/* ==========================================================================
   İLETİŞİM
   ========================================================================== */
.contact { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; }
.contact__item { display: flex; gap: 16px; padding: 20px 0; border-bottom: 1px solid var(--line); }
.contact__item:last-child { border-bottom: 0; }
.contact__item .mdi { font-size: 1.5rem; color: var(--orange); flex: none; }
.contact__item h3 { font-size: 1rem; margin-bottom: 2px; }
.contact__item p, .contact__item a { color: var(--ink-soft); font-size: .96rem; }
.contact__item a:hover { color: var(--orange-dark); }

.form { display: grid; gap: 16px; }
.form .row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field label { display: block; font-size: .85rem; font-weight: 500; margin-bottom: 6px; color: var(--ink); }
.field input, .field textarea {
  width: 100%; font: inherit; font-size: .96rem; color: var(--ink);
  padding: 12px 14px; border: 1px solid var(--line-strong); border-radius: 8px; background: #fff;
  transition: border-color .18s, box-shadow .18s;
}
.field input:focus, .field textarea:focus {
  outline: none; border-color: var(--orange); box-shadow: 0 0 0 3px rgba(243,146,0,.14);
}
.field textarea { resize: vertical; min-height: 130px; }

.map-embed { border: 0; width: 100%; height: 320px; border-radius: var(--radius); margin-top: 40px; }

/* İletişim — bilgiler altalta + tam genişlik harita */
.contact-info { max-width: 620px; margin: 0 auto; }
.map-full { margin-top: clamp(40px, 6vw, 64px); }
.map-full iframe { border: 0; width: 100%; height: clamp(340px, 48vw, 460px); display: block; }

/* sayfa başlığı (iç sayfalar) */
.page-hero { background: var(--bg-soft); border-bottom: 1px solid var(--line); padding: clamp(48px, 7vw, 80px) 0; }
.page-hero h1 { font-size: clamp(1.9rem, 4vw, 2.7rem); font-weight: 700; }
.crumbs { font-size: .88rem; color: var(--ink-soft); margin-bottom: 12px; }
.crumbs a:hover { color: var(--orange-dark); }
.crumbs span { color: var(--line-strong); margin: 0 6px; }

.prose p { margin-bottom: 16px; font-size: 1.04rem; }
.prose h2 { margin: 36px 0 14px; }

/* sayfa başlığında indirme aksiyonu */
.page-hero__row { display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; flex-wrap: wrap; }

/* Tüzük belgesi */
.tuzuk-doc { max-width: 820px; margin: 0 auto; }
.tuzuk-doc__intro {
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 24px; margin-bottom: 40px; display: flex; gap: 16px; align-items: flex-start;
}
.tuzuk-doc__intro .mdi { font-size: 1.6rem; color: var(--orange); flex: none; margin-top: 2px; }
.tuzuk-doc__intro p { font-size: .95rem; margin: 0; }
.tuzuk-sec { margin-bottom: 34px; }
.tuzuk-sec > h2 {
  font-size: 1.18rem; padding-bottom: 10px; margin-bottom: 14px;
  border-bottom: 2px solid var(--orange); display: inline-block;
}
.tuzuk-sec p { margin-bottom: 13px; font-size: 1.0rem; line-height: 1.75; }
.tuzuk-sec .madde { font-weight: 600; color: var(--ink); }
.tuzuk-sec ol, .tuzuk-sec ul { margin: 0 0 14px; padding-left: 24px; }
.tuzuk-sec li { margin-bottom: 8px; color: var(--ink-soft); line-height: 1.7; }
.tuzuk-board {
  list-style: none; padding: 0; margin: 8px 0 14px; display: grid; gap: 10px;
}
.tuzuk-board li {
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: 8px; padding: 12px 16px;
}
.tuzuk-board li strong { color: var(--ink); }
.tuzuk-board li span { color: var(--orange-dark); font-weight: 500; font-size: .92rem; }
.tuzuk-doc__note { margin-top: 36px; padding-top: 20px; border-top: 1px solid var(--line); font-style: italic; color: var(--ink-soft); }

/* ==========================================================================
   FOOTER
   ========================================================================== */
.footer { background: #15181c; color: #c7ccd1; padding-top: 64px; }
.footer a { color: #c7ccd1; transition: color .18s; }
.footer a:hover { color: var(--orange); }
.footer__grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.4fr; gap: 40px; padding-bottom: 48px; }
.footer__brand .brand__mark { font-size: 1.8rem; }
.footer__brand .brand__mark .g { color: #9aa1a8; }
.footer__brand p { color: #9aa1a8; margin-top: 16px; font-size: .94rem; max-width: 300px; }
.footer h4 { color: #fff; font-size: .82rem; letter-spacing: .12em; text-transform: uppercase; margin-bottom: 18px; font-weight: 600; }
.footer ul { list-style: none; display: grid; gap: 11px; }
.footer ul a { font-size: .95rem; }
.footer__contact li { display: flex; gap: 11px; font-size: .94rem; color: #9aa1a8; }
.footer__contact .mdi { color: var(--orange); flex: none; }
.footer__social { display: flex; gap: 10px; margin-top: 20px; }
.footer__social a {
  width: 40px; height: 40px; border-radius: 8px; border: 1px solid #2a2f35;
  display: grid; place-items: center; color: #c7ccd1;
}
.footer__social a:hover { border-color: var(--orange); color: var(--orange); }
.footer__bar {
  border-top: 1px solid #23282e; padding: 22px 0;
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  font-size: .86rem; color: #828990;
}
.footer__made .heart { color: #e23b3b; }
.footer__made a { color: var(--orange); font-weight: 500; }
.footer__made a:hover { color: #fff; }

/* ==========================================================================
   GİRİŞ ANİMASYONLARI (sade)
   ========================================================================== */
/* Animasyon yalnızca JS varken gizler; JS yoksa içerik daima görünür. */
.js .reveal { opacity: 0; transform: translateY(20px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.js .reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  .reveal { opacity: 1; transform: none; }
}

/* ==========================================================================
   DUYARLI (responsive)
   ========================================================================== */
@media (max-width: 960px) {
  .slide__inner { grid-template-columns: 1fr; gap: 30px; }
  .slide__visual { display: none; }
  .about { grid-template-columns: 1fr; gap: 36px; }
  .contact { grid-template-columns: 1fr; gap: 36px; }
  .grid-cards { grid-template-columns: repeat(2, 1fr); }
  .footer__grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .stats__grid { grid-template-columns: 1fr 1fr; }
  .stat:nth-child(3) { border-left: 0; }
  .stat:nth-child(1), .stat:nth-child(2) { border-bottom: 1px solid var(--line); }
}

/* Uzun dernek adını orta boy ekranlarda gizle ki menü tek satıra sığsın */
@media (max-width: 1200px) {
  .brand__name { display: none; }
}

@media (max-width: 960px) {
  .nav__menu {
    position: fixed; inset: 76px 0 auto 0; flex-direction: column; align-items: stretch; gap: 0;
    background: #fff; border-bottom: 1px solid var(--line); padding: 12px 22px 22px;
    box-shadow: var(--shadow); transform: translateY(-12px); opacity: 0; pointer-events: none;
    transition: opacity .22s var(--ease), transform .22s var(--ease);
  }
  .nav.open .nav__menu { opacity: 1; transform: none; pointer-events: auto; }
  .nav__menu a { padding: 13px 8px; border-bottom: 1px solid var(--line); border-radius: 0; white-space: normal; }
  .nav__cta { margin: 12px 0 0; }
  .nav__cta .btn { width: 100%; justify-content: center; }
  .nav__toggle { display: flex; }
  .slider__arrow { display: none; }
  .slider__nav { bottom: 16px; }
}

@media (max-width: 560px) {
  .grid-cards { grid-template-columns: 1fr; }
  .footer__grid { grid-template-columns: 1fr; }
  .form .row { grid-template-columns: 1fr; }
  .cta-band__inner { flex-direction: column; align-items: flex-start; }
  .stats__grid { grid-template-columns: 1fr 1fr; }
  .stat__num { font-size: 1.9rem; }
}