/* ==========================================================================
   FELSEFE TARİHİ — Düşüncenin 2500 Yıllık Yolculuğu
   Design tokens: papirüs & taş tonları, Cormorant Garamond + Inter
   ========================================================================== */

:root {
  /* Color — papyrus & stone, dark ink, single brown accent */
  --color-papyrus: #f2ead9;
  --color-papyrus-deep: #e9dfc7;
  --color-stone: #ddd3ba;
  --color-stone-line: #c9bc9c;
  --color-ink: #2c2620;
  --color-ink-soft: #5a4f42;
  --color-brown: #8a5a34;
  --color-brown-deep: #6a4023;
  --color-panel-bg: #f8f3e6;
  --color-overlay: rgba(38, 32, 24, 0.35);

  /* Type */
  --font-display: "Cormorant Garamond", "Times New Roman", serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

  /* Layout */
  --content-width: 1180px;
  --panel-width: 480px;
  --radius-s: 4px;
  --radius-m: 8px;

  /* Motion */
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --dur-fast: 160ms;
  --dur-med: 320ms;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--color-papyrus);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body.panel-open {
  position: fixed;
  width: 100%;
}

a {
  color: inherit;
}

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

button {
  font-family: inherit;
  cursor: pointer;
}

::selection {
  background: var(--color-brown);
  color: var(--color-papyrus);
}

:focus-visible {
  outline: 2px solid var(--color-brown);
  outline-offset: 2px;
}

/* Subtle paper grain, sits behind everything */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.5;
  background-image: radial-gradient(circle at 1px 1px, rgba(90, 79, 66, 0.06) 1px, transparent 0);
  background-size: 3px 3px;
}

/* ==========================================================================
   HERO
   ========================================================================== */

.hero {
  position: relative;
  z-index: 10;
  padding: 96px 24px 64px;
  text-align: center;
}

.hero__glyph {
  font-family: var(--font-display);
  font-size: 40px;
  color: var(--color-brown);
  margin-bottom: 12px;
}

.hero__title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(40px, 7vw, 68px);
  letter-spacing: -0.01em;
  margin: 0 0 14px;
}

.hero__subtitle {
  font-size: 17px;
  color: var(--color-ink-soft);
  letter-spacing: 0.02em;
  margin: 0 0 40px;
}

/* Search */
.search-wrap {
  position: relative;
  max-width: 520px;
  margin: 0 auto;
}

.search-input {
  width: 100%;
  padding: 15px 20px;
  font-size: 15.5px;
  font-family: var(--font-body);
  color: var(--color-ink);
  background: var(--color-panel-bg);
  border: 1px solid var(--color-stone-line);
  border-radius: 999px;
  transition: border-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}

.search-input::placeholder {
  color: #a99d87;
}

.search-input:focus {
  outline: none;
  border-color: var(--color-brown);
  box-shadow: 0 0 0 4px rgba(138, 90, 52, 0.1);
}

.search-results {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  right: 0;
  background: var(--color-panel-bg);
  border: 1px solid var(--color-stone-line);
  border-radius: var(--radius-m);
  box-shadow: 0 16px 40px rgba(44, 38, 32, 0.14);
  overflow: hidden;
  text-align: left;
  z-index: 20;
  display: none;
  max-height: 360px;
  overflow-y: auto;
}

.search-results.is-open {
  display: block;
}

.search-result {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 12px 18px;
  background: none;
  border: none;
  text-align: left;
  border-bottom: 1px solid var(--color-stone);
}

.search-result:last-child {
  border-bottom: none;
}

.search-result:hover,
.search-result:focus-visible {
  background: var(--color-stone);
}

.search-result__title {
  font-family: var(--font-display);
  font-size: 18px;
}

.search-result__sub {
  font-size: 12.5px;
  color: var(--color-ink-soft);
}

.search-empty {
  padding: 16px 18px;
  font-size: 14px;
  color: var(--color-ink-soft);
}

/* ==========================================================================
   TYPE TAG — shared badge used in timeline nodes, panel header, search
   ========================================================================== */

.type-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-body);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--color-brown-deep);
}

.type-tag__shape {
  display: inline-block;
  width: 8px;
  height: 8px;
  flex-shrink: 0;
}

/* shape variants, drawn with pure CSS so new types only need a class */
.shape-circle {
  border-radius: 50%;
  background: var(--color-brown);
}

.shape-square {
  background: var(--color-brown);
}

.shape-diamond {
  background: var(--color-brown);
  transform: rotate(45deg);
}

.shape-triangle {
  width: 0 !important;
  height: 0 !important;
  background: none !important;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-bottom: 8px solid var(--color-brown);
}

.shape-star {
  background: var(--color-brown);
  clip-path: polygon(50% 0%, 61% 35%, 98% 35%, 68% 57%, 79% 91%, 50% 70%, 21% 91%, 32% 57%, 2% 35%, 39% 35%);
}

.shape-hex {
  background: var(--color-brown);
  clip-path: polygon(25% 6%, 75% 6%, 100% 50%, 75% 94%, 25% 94%, 0% 50%);
}

/* ==========================================================================
   TIMELINE
   ========================================================================== */

.timeline-section {
  position: relative;
  z-index: 1;
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 40px 24px 160px;
}

.timeline {
  position: relative;
}

/* the spine — signature element: a flowing thread, echoing Herakleitos'un
   "panta rhei" (her şey akar) fikrini, düşünce tarihini birbirine bağlayan
   tek bir çizgi olarak */
.timeline__spine {
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  transform: translateX(-50%);
  background: linear-gradient(
    to bottom,
    transparent 0%,
    var(--color-stone-line) 4%,
    var(--color-stone-line) 96%,
    transparent 100%
  );
}

.timeline__spine::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, transparent, rgba(138, 90, 52, 0.5), transparent);
  background-size: 100% 240px;
  animation: flow 9s linear infinite;
}

@keyframes flow {
  0% {
    background-position: 0 -240px;
  }
  100% {
    background-position: 0 480px;
  }
}

.timeline__row {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  align-items: center;
  min-height: 84px;
  margin-bottom: 48px;
}

.timeline__node {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 2;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--color-papyrus);
  border: 1px solid var(--color-stone-line);
  transition: transform var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.timeline__node .type-tag__shape {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.timeline__node .shape-diamond {
  transform: translate(-50%, -50%) rotate(45deg);
}

.timeline__row:hover .timeline__node {
  border-color: var(--color-brown);
  transform: translate(-50%, -50%) scale(1.08);
}

.timeline__card {
  background: var(--color-panel-bg);
  border: 1px solid transparent;
  border-radius: var(--radius-m);
  padding: 16px 20px;
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease),
    box-shadow var(--dur-fast) var(--ease);
  max-width: 420px;
}

.timeline__row:hover .timeline__card,
.timeline__card:focus-visible {
  border-color: var(--color-stone-line);
  box-shadow: 0 8px 24px rgba(44, 38, 32, 0.08);
  transform: translateY(-1px);
}

.timeline__row--left .timeline__card {
  grid-column: 1;
  justify-self: end;
  text-align: right;
  margin-right: 40px;
}

.timeline__row--right .timeline__card {
  grid-column: 2;
  justify-self: start;
  text-align: left;
  margin-left: 40px;
}

.timeline__year {
  font-family: var(--font-display);
  font-size: 15px;
  color: var(--color-brown-deep);
  position: absolute;
  left: 50%;
  top: -34px;
  transform: translateX(-50%);
  white-space: nowrap;
  background: var(--color-papyrus);
  border: 1px solid var(--color-stone-line);
  border-radius: 999px;
  padding: 2px 12px;
  z-index: 3;
}

.timeline__card .type-tag {
  margin-bottom: 6px;
}

.timeline__card h3 {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 500;
  margin: 0 0 4px;
}

.timeline__card p {
  margin: 0;
  font-size: 13.5px;
  color: var(--color-ink-soft);
}

.load-error {
  max-width: 560px;
  margin: 40px auto;
  padding: 28px 32px;
  background: var(--color-panel-bg);
  border: 1px solid var(--color-stone-line);
  border-radius: var(--radius-m);
  text-align: left;
}

.load-error h3 {
  font-family: var(--font-display);
  font-size: 24px;
  margin: 0 0 12px;
  color: var(--color-brown-deep);
}

.load-error p {
  font-size: 14.5px;
  color: var(--color-ink-soft);
  margin: 0 0 12px;
}

.load-error code {
  background: var(--color-stone);
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 13px;
}

.load-error pre {
  background: var(--color-ink);
  color: var(--color-papyrus);
  padding: 12px 16px;
  border-radius: var(--radius-s);
  font-size: 13.5px;
  overflow-x: auto;
  margin: 0 0 12px;
}

.timeline__end {
  text-align: center;
  padding-top: 48px;
  color: var(--color-ink-soft);
  font-size: 14px;
}

/* ==========================================================================
   SIDE PANEL
   ========================================================================== */

.overlay {
  position: fixed;
  inset: 0;
  background: var(--color-overlay);
  backdrop-filter: blur(2px);
  z-index: 40;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur-med) var(--ease);
}

.overlay.is-open {
  opacity: 1;
  pointer-events: auto;
}

.panel {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(var(--panel-width), 100vw);
  background: var(--color-panel-bg);
  z-index: 50;
  box-shadow: -24px 0 60px rgba(44, 38, 32, 0.18);
  transform: translateX(100%);
  transition: transform var(--dur-med) var(--ease);
  display: flex;
  flex-direction: column;
}

.panel.is-open {
  transform: translateX(0);
}

.panel__scroll {
  overflow-y: auto;
  padding: 32px 36px 64px;
  flex: 1;
}

.panel__close {
  position: absolute;
  top: 20px;
  right: 20px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--color-stone-line);
  background: var(--color-panel-bg);
  font-size: 16px;
  color: var(--color-ink-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2;
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}

.panel__close:hover {
  background: var(--color-stone);
  color: var(--color-ink);
}

.panel__emblem {
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-m);
  margin: 8px 0 24px;
  overflow: hidden;
  background: var(--color-stone);
}

.panel__emblem svg {
  width: 100%;
  height: 100%;
}

.panel__type {
  margin-bottom: 10px;
}

.panel__title {
  font-family: var(--font-display);
  font-size: 40px;
  font-weight: 500;
  margin: 0 0 4px;
  line-height: 1.05;
}

.panel__subtitle {
  font-size: 15px;
  color: var(--color-ink-soft);
  font-style: italic;
  margin: 0 0 4px;
}

.panel__dates {
  font-size: 13px;
  color: var(--color-brown-deep);
  letter-spacing: 0.03em;
  margin: 0 0 20px;
}

.panel__tagline {
  font-family: var(--font-display);
  font-size: 20px;
  color: var(--color-brown-deep);
  border-left: 2px solid var(--color-brown);
  padding-left: 14px;
  margin: 0 0 28px;
}

.panel__section {
  margin-bottom: 26px;
}

.panel__section h4 {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-ink-soft);
  margin: 0 0 10px;
}

.panel__section p {
  margin: 0;
  font-size: 15px;
  color: var(--color-ink);
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 13px;
  background: var(--color-stone);
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 13.5px;
  color: var(--color-ink);
  transition: background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}

.chip:hover,
.chip:focus-visible {
  background: var(--color-panel-bg);
  border-color: var(--color-brown);
}

.chip .type-tag__shape {
  width: 7px;
  height: 7px;
}

.panel__sources {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 13px;
  color: var(--color-ink-soft);
}

.panel__sources li {
  padding: 6px 0;
  border-top: 1px solid var(--color-stone);
}

.panel__divider {
  border: none;
  border-top: 1px solid var(--color-stone);
  margin: 28px 0;
}

.panel__empty {
  font-size: 13.5px;
  color: var(--color-ink-soft);
  font-style: italic;
}

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */

@media (max-width: 760px) {
  .hero {
    padding: 64px 20px 40px;
  }

  .timeline-section {
    padding: 24px 16px 100px;
  }

  .timeline__spine {
    left: 20px;
  }

  .timeline__row {
    grid-template-columns: 1fr;
    min-height: auto;
    margin-bottom: 56px;
  }

  .timeline__node {
    top: 50%;
    left: 20px;
    width: 28px;
    height: 28px;
  }

  .timeline__row--left .timeline__card,
  .timeline__row--right .timeline__card {
    grid-column: 1;
    justify-self: stretch;
    text-align: left;
    max-width: none;
    margin-left: 44px;
    margin-right: 0;
  }

  .timeline__year {
    left: 44px;
    top: -38px;
    transform: none;
    padding: 2px 10px;
    border-radius: 999px;
  }

  .panel {
    width: 100vw;
  }

  .panel__scroll {
    padding: 26px 20px 48px;
  }

  .panel__title {
    font-size: 32px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .timeline__spine::after {
    animation: none;
  }

  * {
    transition-duration: 1ms !important;
  }
}