/* ================================================
   Signifer 人工 Lab — Shared Styles
   ================================================ */

:root {
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --t-color:  150ms var(--ease);
  --t-fast:   200ms var(--ease);
  --t-mid:    300ms var(--ease);
  --t-reveal: 400ms var(--ease);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }

/* Fixed 4px black border around viewport */
.border-top, .border-bottom, .border-left, .border-right {
  position: fixed;
  z-index: 9999;
  pointer-events: none;
}
.border-top {
  top: 0; left: 0; right: 0;
  height: 12px;
  background: #E8521A;
  animation: breathe-h 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}
.border-bottom {
  bottom: 0; left: 0; right: 0;
  height: 12px;
  background: #74290D;
  animation: breathe-h 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}
.border-left {
  top: 0; bottom: 0; left: 0;
  width: 12px;
  background: linear-gradient(to bottom, #E8521A 0%, #74290D 40%);
  animation: breathe-w 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}
.border-right {
  top: 0; bottom: 0; right: 0;
  width: 12px;
  background: linear-gradient(to bottom, #E8521A 0%, #74290D 40%);
  animation: breathe-w 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

@media (max-width: 768px) {
  .border-top, .border-bottom, .border-left, .border-right {
    display: none;
  }
}

@keyframes breathe-h {
  0% { height: 12px; }
  40% { height: 10px; }
  70% { height: 13px; }
  100% { height: 12px; }
}
@keyframes breathe-w {
  0% { width: 12px; }
  40% { width: 10px; }
  70% { width: 13px; }
  100% { width: 12px; }
}

body {
  font-family: 'Inter', sans-serif;
  background: #F5F4F1;
  color: #1A1A1A;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }

.nav-link {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #1A1A1A;
  transition: all 0.2s var(--ease);
}
.nav-link:hover { text-decoration: underline; text-underline-offset: 4px; text-decoration-thickness: 1px; }
.nav-link.active { text-decoration: underline; text-underline-offset: 4px; text-decoration-thickness: 1px; text-decoration-color: #E8521A; }

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.75rem 1.5rem;
  border: 1px solid transparent;
  background: #E8521A;
  color: #fff;
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease);
}
.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #8B7D5E;
  padding: 0.75rem 1.5rem;
  border: 1px solid #8B7D5E;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.text-link:hover { color: #1A1A1A; border-color: #1A1A1A; }
ul, ol { list-style: none; }
button { font: inherit; cursor: pointer; border: none; background: none; }
input, textarea, select { font: inherit; background: none; }
img, svg { display: block; max-width: 100%; }
::selection { background: rgba(232, 82, 26, 0.15); }

/* ================================================
   Editorial Grid (pattern blocks)
   ================================================ */
.editorial-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 3rem;
  align-items: end;
  padding: 2.5rem;
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: 2px;
}
@media (max-width: 768px) {
  .editorial-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 1.5rem;
  }
}

/* ================================================
   Typography
   ================================================ */

.label {
  display: block;
  font-size: 0.625rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #999;
  margin-bottom: 1.5rem;
}

.label::after {
  content: '';
  display: inline-block;
  width: 5px;
  height: 5px;
  background: #E8521A;
  margin-left: 0.5em;
  vertical-align: middle;
  animation: blink 1.5s linear infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.nav-cta-pulse {
  animation: cta-pulse 2s ease-in-out infinite !important;
  border-radius: 2px;
}
@keyframes cta-pulse {
  0%, 100% { box-shadow: 0 0 8px 2px rgba(232, 82, 26, 0.6), 0 0 20px 6px rgba(232, 82, 26, 0.3) !important; }
  50% { box-shadow: 0 0 16px 6px rgba(232, 82, 26, 0.8), 0 0 40px 14px rgba(232, 82, 26, 0.4) !important; }
}

.page-title {
  font-family: 'Sofia Sans Condensed', 'Inter', sans-serif;
  font-weight: 300;
  font-size: clamp(2.5rem, 7vw, 4.5rem);
  line-height: 0.95;
  letter-spacing: -0.02em;
  color: #1A1A1A;
  text-transform: uppercase;
}

.body-text {
  font-size: 1.125rem;
  font-weight: 300;
  line-height: 1.7;
  color: #6B6B6B;
}

/* ================================================
   Navigation
   ================================================ */

.site-nav {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 50;
}

/* Progressive blur layers — desktop (top, fades downward) */
.nav-blur-layer {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
.nav-blur-1 { backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px); mask: linear-gradient(to top, transparent 0%, transparent 80%, black 100%); -webkit-mask: linear-gradient(to top, transparent 0%, transparent 80%, black 100%); }
.nav-blur-2 { backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px); mask: linear-gradient(to top, transparent 0%, transparent 60%, black 100%); -webkit-mask: linear-gradient(to top, transparent 0%, transparent 60%, black 100%); }
.nav-blur-3 { backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); mask: linear-gradient(to top, transparent 0%, transparent 42%, black 100%); -webkit-mask: linear-gradient(to top, transparent 0%, transparent 42%, black 100%); }
.nav-blur-4 { backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); mask: linear-gradient(to top, transparent 0%, transparent 25%, black 100%); -webkit-mask: linear-gradient(to top, transparent 0%, transparent 25%, black 100%); }
.nav-blur-5 { backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px); mask: linear-gradient(to top, transparent 0%, transparent 10%, black 100%); -webkit-mask: linear-gradient(to top, transparent 0%, transparent 10%, black 100%); }

/* Gradient color overlay — subtle tint matching page bg */
.nav-fade {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(to bottom,
    rgba(245, 244, 241, 0.5) 0%,
    rgba(245, 244, 241, 0.3) 40%,
    rgba(245, 244, 241, 0.0) 100%
  );
}

/* duplicate nav-link removed — defined above */

.nav-link.active-legacy {
  border-bottom: 1px solid #E8521A;
}

/* Mobile nav — bottom sticky, flip blur direction */
@media (max-width: 768px) {
  .site-nav {
    top: auto;
    bottom: 0;
    padding-bottom: 0 !important;
    margin-bottom: 0 !important;
    padding-top: 280px;
    margin-top: -280px;
  }
  .nav-blur-1 { mask: linear-gradient(to bottom, transparent 0%, transparent 85%, black 100%); -webkit-mask: linear-gradient(to bottom, transparent 0%, transparent 85%, black 100%); }
  .nav-blur-2 { mask: linear-gradient(to bottom, transparent 0%, transparent 70%, black 100%); -webkit-mask: linear-gradient(to bottom, transparent 0%, transparent 70%, black 100%); }
  .nav-blur-3 { mask: linear-gradient(to bottom, transparent 0%, transparent 55%, black 100%); -webkit-mask: linear-gradient(to bottom, transparent 0%, transparent 55%, black 100%); }
  .nav-blur-4 { mask: linear-gradient(to bottom, transparent 0%, transparent 40%, black 100%); -webkit-mask: linear-gradient(to bottom, transparent 0%, transparent 40%, black 100%); }
  .nav-blur-5 { mask: linear-gradient(to bottom, transparent 0%, transparent 25%, black 100%); -webkit-mask: linear-gradient(to bottom, transparent 0%, transparent 25%, black 100%); }
  .nav-fade {
    background: linear-gradient(to top,
      rgba(245, 244, 241, 0.5) 0%,
      rgba(245, 244, 241, 0.3) 40%,
      rgba(245, 244, 241, 0.0) 100%
    );
  }
}

/* Mobile menu overlay */
.mobile-menu {
  opacity: 0;
  max-height: 0;
  overflow: hidden;
  pointer-events: none;
  transform: translateY(8px);
  background: transparent;
  transition:
    opacity var(--t-mid),
    transform var(--t-mid),
    max-height var(--t-mid);
}

.mobile-menu.open {
  opacity: 1;
  max-height: 400px;
  pointer-events: all;
  transform: translateY(0);
  padding: 1rem 0 1.5rem;
}

/* ================================================
   Cards
   ================================================ */

.card {
  transition: background var(--t-fast), transform var(--t-fast);
}

@media (hover: hover) {
  .card:hover {
    transform: translateY(-2px);
  }
}

/* ================================================
   Buttons
   ================================================ */

.btn-primary {
  transition: background var(--t-color), opacity var(--t-color);
}

@media (hover: hover) {
  .btn-primary:hover {
    background: #d44a16;
  }
}

.btn-primary:active {
  opacity: 0.85;
  transition-duration: 80ms;
}

.text-link {
  transition: color var(--t-color);
}

/* ================================================
   Form
   ================================================ */

.form-input {
  background: #F5F4F2;
  border-bottom: 1px solid rgba(0, 0, 0, 0.2);
  outline: none;
  padding: 0.5rem 0.3rem;
  font-size: 1rem;
  width: 100%;
  transition:
    border-color var(--t-color),
    box-shadow var(--t-color);
}

.form-input:focus {
  border-color: rgba(0, 0, 0, 0.3);
  box-shadow: 0 0 0 3px rgba(232, 82, 26, 0.12);
}

.form-container {
  transition: opacity var(--t-mid);
}

.form-container.submitting {
  opacity: 0.5;
  pointer-events: none;
}

input::placeholder,
textarea::placeholder {
  font-size: 0.8em;
}

/* ================================================
   Scroll reveal
   ================================================ */

/* Reveal animation — only hide when JS is available */
.js-loaded .reveal {
  opacity: 0;
  transform: translateY(24px);
}

.reveal {
  transition:
    opacity var(--t-reveal),
    transform var(--t-reveal);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ================================================
   Background symbol
   ================================================ */

.bg-symbol {
  position: fixed;
  bottom: 0;
  right: -15%;
  height: 173vh;
  width: auto;
  opacity: 0.105;
  filter: brightness(0);
  pointer-events: none;
  z-index: -1;
  user-select: none;
}

/* ================================================
   Layout
   ================================================ */

.editorial-grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 4rem;
}
@media (max-width: 768px) {
  .editorial-grid { grid-template-columns: 1fr; gap: 2rem; }
}

/* ================================================
   Material icons
   ================================================ */

.material-symbols-outlined {
  font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0, 'opsz' 24;
  display: inline-block;
  vertical-align: middle;
}