/**
 * SUEWS Base Styles
 *
 * Shared CSS for typography, resets, theme toggle, footer, and common components.
 * Requires tokens.css to be loaded first.
 */

/* ========== Reset ========== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

/* ========== Typography ========== */
body {
  font-family: 'Instrument Sans', system-ui, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
  min-height: 100vh;
  transition: background-color var(--transition-standard), color var(--transition-standard);
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Crimson Pro', Georgia, serif;
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

h1 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  margin-bottom: 0.5rem;
}

h2 {
  font-size: 1.5rem;
  font-weight: 400;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 3rem;
}

code, pre, .mono {
  font-family: 'JetBrains Mono', monospace;
}

/* ========== Links ========== */
a {
  color: var(--accent-highlight);
  text-decoration: none;
  transition: color var(--transition-standard);
}

a:hover {
  text-decoration: underline;
}

/* ========== Container ========== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== Theme Toggle Button ========== */
.theme-toggle {
  position: fixed;
  top: 24px;
  right: 24px;
  z-index: 1000;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  border: 1px solid var(--border-light);
  background: var(--bg-card);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-standard);
  backdrop-filter: blur(8px);
}

.theme-toggle:hover {
  border-color: var(--border-medium);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  stroke: var(--text-secondary);
  stroke-width: 2;
  fill: none;
  transition: stroke var(--transition-standard);
}

.theme-toggle:hover svg {
  stroke: var(--text-primary);
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  position: absolute;
  transition: opacity var(--transition-standard), transform var(--transition-standard);
}

/* Dark mode (default): show sun icon (to switch to light) */
:root:not([data-theme="light"]) .theme-toggle .icon-sun { opacity: 1; transform: rotate(0deg); }
:root:not([data-theme="light"]) .theme-toggle .icon-moon { opacity: 0; transform: rotate(-90deg); }

/* Light mode: show moon icon (to switch to dark) */
[data-theme="light"] .theme-toggle .icon-sun { opacity: 0; transform: rotate(90deg); }
[data-theme="light"] .theme-toggle .icon-moon { opacity: 1; transform: rotate(0deg); }

/* System light preference without explicit theme */
@media (prefers-color-scheme: light) {
  :root:not([data-theme]) .theme-toggle .icon-sun { opacity: 0; transform: rotate(90deg); }
  :root:not([data-theme]) .theme-toggle .icon-moon { opacity: 1; transform: rotate(0deg); }
}

/* Light-default pages: reverse the icon logic */
.light-default:not([data-theme="dark"]) .theme-toggle .icon-sun { opacity: 0; transform: rotate(90deg); }
.light-default:not([data-theme="dark"]) .theme-toggle .icon-moon { opacity: 1; transform: rotate(0deg); }
.light-default[data-theme="dark"] .theme-toggle .icon-sun { opacity: 1; transform: rotate(0deg); }
.light-default[data-theme="dark"] .theme-toggle .icon-moon { opacity: 0; transform: rotate(-90deg); }

/* ========== Footer ========== */
.footer {
  border-top: 1px solid var(--border-light);
  padding: 60px 0;
  text-align: center;
  background: var(--bg-secondary);
  transition: background-color var(--transition-standard), border-color var(--transition-standard);
}

.footer-institutions {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 24px;
  line-height: 1.8;
}

.footer-legal {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer a {
  color: var(--text-muted);
}

.footer a:hover {
  color: var(--text-secondary);
}

/* ========== Section Headers ========== */
.section-header {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-bottom: 60px;
}

.section-number {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem;
  color: var(--water-blue);
  letter-spacing: 0.1em;
}

.section-line {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border-medium), transparent);
}

/* ========== Card Base ========== */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 24px;
  box-shadow: var(--shadow-card);
  transition: all var(--transition-card);
}

.card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-medium);
  transform: translateY(-4px);
}

/* ========== Animations ========== */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

/* ========== Logo Animations ========== */
@keyframes sun-glow {
  0%, 100% { transform: scale(0.96); }
  50% { transform: scale(1.06); }
}

@keyframes wave-undulate {
  0%, 100% {
    transform: translateY(0) scaleY(1);
  }
  50% {
    transform: translateY(2px) scaleY(0.95);
  }
}

/* ========== Responsive Breakpoints ========== */
@media (max-width: 900px) {
  .container {
    padding: 0 16px;
  }
}

@media (max-width: 600px) {
  .theme-toggle {
    top: 16px;
    right: 16px;
    width: 40px;
    height: 40px;
  }
}