/* ============================================================
   tfkir.net — Design System / Base
   الدكتور ياسر حسن — موقع شخصي
   ============================================================ */

/* ---------- Fonts ---------- */
@import url("https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+Arabic:wght@300;400;500;600;700&family=Noto+Naskh+Arabic:wght@400;500;600;700&display=swap");

/* ---------- Tokens ---------- */
:root {
  /* Brand */
  --ink-900: #05080b;
  --ink-850: #070b10;
  --ink-800: #0a0f15;
  --ink-750: #0e141b;
  --ink-700: #131b24;
  --ink-600: #1b2530;
  --ink-500: #263341;
  --line: rgba(255, 255, 255, 0.08);
  --line-strong: rgba(255, 255, 255, 0.16);

  /* Teal — medicine / clinical calm */
  --teal-100: #d6f7f0;
  --teal-300: #6fe3d0;
  --teal-400: #34d0b8;
  --teal-500: #14b8a6;
  --teal-600: #0d9488;
  --teal-700: #0b7268;

  /* Brass — thought / philosophy */
  --brass-100: #f8eecd;
  --brass-300: #e8cf8a;
  --brass-400: #d9b96a;
  --brass-500: #c39b3f;
  --brass-600: #9a7628;

  /* Text */
  --text: #e9edf2;
  --text-soft: #c3ccd6;
  --muted: #8b97a5;
  --faint: #7a8694;

  /* Semantic */
  --bg: var(--ink-900);
  --bg-elev: var(--ink-800);
  --surface: rgba(255, 255, 255, 0.028);
  --surface-2: rgba(255, 255, 255, 0.05);
  --accent: var(--teal-400);
  --accent-2: var(--brass-400);

  /* Gradients */
  --grad-brand: linear-gradient(115deg, var(--teal-400) 0%, #7fd7e8 45%, var(--brass-400) 100%);
  --grad-brand-soft: linear-gradient(115deg, rgba(52, 208, 184, 0.16), rgba(217, 185, 106, 0.14));
  --grad-fade-x: linear-gradient(90deg, transparent, var(--ink-850) 82%);

  /* Typography */
  --font-display: "Noto Naskh Arabic", "IBM Plex Sans Arabic", "Amiri", serif;
  --font-body: "IBM Plex Sans Arabic", "Segoe UI", system-ui, sans-serif;
  --font-serif: "Noto Naskh Arabic", "Amiri", "Times New Roman", serif;
  --font-latin: "IBM Plex Sans Arabic", "Noto Naskh Arabic", system-ui, sans-serif;

  /* Fluid type scale */
  --fs-hero: clamp(2.55rem, 1.15rem + 5.4vw, 6.1rem);
  --fs-h1: clamp(2rem, 1.15rem + 3.4vw, 4.15rem);
  --fs-h2: clamp(1.62rem, 1.1rem + 2.1vw, 2.9rem);
  --fs-h3: clamp(1.22rem, 0.98rem + 0.95vw, 1.72rem);
  --fs-h4: clamp(1.06rem, 0.95rem + 0.5vw, 1.28rem);
  --fs-lead: clamp(1.02rem, 0.95rem + 0.45vw, 1.32rem);
  --fs-body: clamp(0.97rem, 0.93rem + 0.2vw, 1.06rem);
  --fs-sm: 0.875rem;
  --fs-xs: 0.775rem;
  --fs-kicker: 0.735rem;

  /* Space */
  --shell: 1240px;
  --shell-narrow: 820px;
  --gut: clamp(1.15rem, 0.6rem + 2.4vw, 2.75rem);
  --sect-y: clamp(3.75rem, 2rem + 7vw, 8.5rem);

  /* Radii */
  --r-xs: 6px;
  --r-sm: 10px;
  --r-md: 16px;
  --r-lg: 22px;
  --r-xl: 30px;
  --r-pill: 999px;

  /* Shadows */
  --sh-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --sh-md: 0 14px 34px -14px rgba(0, 0, 0, 0.65);
  --sh-lg: 0 34px 80px -30px rgba(0, 0, 0, 0.8);
  --sh-glow: 0 0 0 1px rgba(52, 208, 184, 0.25), 0 22px 60px -26px rgba(52, 208, 184, 0.45);

  --ease: cubic-bezier(0.22, 0.68, 0.24, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur: 0.55s;

  --header-h: 74px;
  color-scheme: dark;
}

/* ---------- Light theme ---------- */
[data-theme="light"] {
  --ink-900: #f6f8fa;
  --ink-850: #ffffff;
  --ink-800: #ffffff;
  --ink-750: #f2f5f8;
  --ink-700: #eaeff4;
  --ink-600: #dde5ec;
  --ink-500: #c8d3dd;
  --line: rgba(9, 20, 28, 0.09);
  --line-strong: rgba(9, 20, 28, 0.17);
  --text: #0d151c;
  --text-soft: #26333f;
  --muted: #5a6a78;
  --faint: #6b7b8a;
  --surface: rgba(10, 25, 35, 0.028);
  --surface-2: rgba(10, 25, 35, 0.05);
  --teal-500: #0c8b7e;
  --teal-400: #0d9488;
  --teal-600: #0a7268;
  --teal-100: #0a5f56;
  --brass-500: #8a6a1f;
  --brass-400: #a37f2a;
  --grad-brand: linear-gradient(115deg, #0d9488 0%, #2b7fa8 45%, #a37f2a 100%);
  --grad-brand-soft: linear-gradient(115deg, rgba(13, 148, 136, 0.1), rgba(163, 127, 42, 0.1));
  --grad-fade-x: linear-gradient(90deg, transparent, #fff 82%);
  --sh-md: 0 14px 34px -18px rgba(13, 30, 45, 0.28);
  --sh-lg: 0 30px 70px -34px rgba(13, 30, 45, 0.3);
  color-scheme: light;
}

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

* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 18px);
}

body {
  min-height: 100dvh;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.85;
  font-weight: 400;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
}

/* Ambient background layers */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -3;
  background:
    radial-gradient(880px 620px at 88% -8%, rgba(52, 208, 184, 0.13), transparent 62%),
    radial-gradient(760px 560px at 4% 8%, rgba(217, 185, 106, 0.1), transparent 60%),
    radial-gradient(1100px 780px at 50% 108%, rgba(45, 120, 160, 0.11), transparent 66%),
    var(--bg);
}

/* Fine grain */
body::after {
  content: "";
  position: fixed;
  inset: -50%;
  z-index: -2;
  pointer-events: none;
  opacity: 0.032;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  animation: grain 7s steps(6) infinite;
}

@keyframes grain {
  0%, 100% { transform: translate(0, 0); }
  20% { transform: translate(-4%, 3%); }
  40% { transform: translate(3%, -4%); }
  60% { transform: translate(-3%, -3%); }
  80% { transform: translate(4%, 4%); }
}

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

button, input, textarea, select {
  font: inherit;
  color: inherit;
}

button { cursor: pointer; background: none; border: none; }

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--teal-300); }

ul, ol { padding-inline-start: 1.25em; }

hr {
  border: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line-strong), transparent);
  margin-block: 2.5rem;
}

:focus-visible {
  outline: 2px solid var(--teal-400);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: rgba(52, 208, 184, 0.28);
  color: var(--text);
}

::-webkit-scrollbar { width: 11px; height: 11px; }
::-webkit-scrollbar-track { background: var(--ink-850); }
::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--teal-600), var(--brass-600));
  border-radius: 99px;
  border: 3px solid var(--ink-850);
}

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.005em;
  color: var(--text);
  text-wrap: balance;
}

h1 { font-size: var(--fs-h1); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }
h4 { font-size: var(--fs-h4); }

p { text-wrap: pretty; }

strong, b { font-weight: 600; color: var(--text); }

.lead {
  font-size: var(--fs-lead);
  color: var(--text-soft);
  line-height: 1.9;
  font-weight: 400;
}

.kicker {
  font-family: var(--font-latin);
  font-size: var(--fs-kicker);
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--teal-400);
  display: inline-flex;
  align-items: center;
  gap: 0.7em;
}

.kicker::before {
  content: "";
  width: clamp(20px, 4vw, 42px);
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--teal-400));
}

.latin {
  font-family: var(--font-latin);
  font-variant-numeric: tabular-nums;
  direction: ltr;
  unicode-bidi: isolate;
}

.serif {
  font-family: var(--font-serif);
  font-weight: 400;
  line-height: 2.05;
}

.gradient-text {
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.mark { background: linear-gradient(transparent 62%, rgba(217, 185, 106, 0.28) 62%); }
[data-theme="light"] .mark {
  background: linear-gradient(transparent 62%, rgba(163, 127, 42, 0.24) 62%);
}

/* ---------- Layout ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gut);
}

.shell--narrow { max-width: var(--shell-narrow); }

.section { padding-block: var(--sect-y); position: relative; }
.section--tight { padding-block: clamp(2.5rem, 1.5rem + 3.5vw, 4.75rem); }

.sect-head { max-width: 68ch; margin-bottom: clamp(2rem, 1.2rem + 2.4vw, 3.4rem); }
.sect-head > * + * { margin-top: 0.85rem; }

.sect-head--center {
  margin-inline: auto;
  text-align: center;
}
.sect-head--center .kicker { justify-content: center; }
.sect-head--center .kicker::before { display: none; }

.grid { display: grid; gap: clamp(1rem, 0.6rem + 1.4vw, 1.7rem); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 310px), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 275px), 1fr)); }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 215px), 1fr)); }

.divider { height: 1px; background: linear-gradient(90deg, transparent, var(--line-strong), transparent); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.45em;
  padding: 0.32em 0.85em;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-pill);
  font-size: var(--fs-xs);
  font-weight: 500;
  color: var(--text-soft);
  background: var(--surface);
  white-space: nowrap;
}

.tag--teal { border-color: rgba(52, 208, 184, 0.32); color: var(--teal-300); background: rgba(52, 208, 184, 0.07); }
.tag--brass { border-color: rgba(217, 185, 106, 0.32); color: var(--brass-300); background: rgba(217, 185, 106, 0.07); }

.skip-link {
  position: fixed;
  inset-block-start: 10px;
  inset-inline-start: 50%;
  transform: translate(-50%, -160%);
  z-index: 999;
  padding: 0.7rem 1.4rem;
  background: var(--ink-700);
  border: 1px solid var(--teal-500);
  border-radius: var(--r-pill);
  transition: transform 0.25s var(--ease);
}
.skip-link:focus { transform: translate(50%, 0); color: var(--text); }

/* ---------- Accessibility helpers ---------- */
.sr-only {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

[hidden] { display: none !important; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  body::after { animation: none; }
}

@media print {
  .site-header, .site-footer, .hero__portrait, .fab, .to-top { display: none !important; }
  body { background: #fff; color: #000; }
  body::before, body::after { display: none; }
}