/* =========================================
   SeaSignal Theme - Main Stylesheet
   ========================================= */

:root {
  --color-bg:       #F2F2F4;
  --color-accent:   #534AB7;
  --color-accent-hover: #4239a0;
  --color-dark:     #1A1A2E;
  --color-white:    #FFFFFF;
  --color-border:   #E0E0E8;
  --color-text-muted: #6B6B8A;
  --radius:         12px;
  --radius-sm:      8px;
  --shadow-card:    0 2px 12px rgba(83, 74, 183, 0.08);
  --shadow-hover:   0 6px 24px rgba(83, 74, 183, 0.16);
  --font-base:      -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --transition:     0.2s ease;
}

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

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: var(--font-base);
  background-color: var(--color-bg);
  color: var(--color-dark);
  line-height: 1.6;
  min-height: 100vh;
}

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

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

/* ----- Layout ----- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ----- Site Header ----- */
.site-header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 16px;
}

.site-logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-accent);
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.site-logo span {
  color: var(--color-dark);
}

/* ----- Language Switcher ----- */
.lang-switcher {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}

.lang-switcher__btn {
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--color-text-muted);
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font-base);
}

.lang-switcher__btn:hover,
.lang-switcher__btn.is-active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-white);
}

/* ----- Tab Navigation ----- */
.tab-nav {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  overflow-x: auto;
  scrollbar-width: none;
}

.tab-nav::-webkit-scrollbar { display: none; }

.tab-nav__list {
  display: flex;
  list-style: none;
  min-width: max-content;
  padding: 0 20px;
}

.tab-nav__item {}

.tab-nav__btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 14px 18px;
  border: none;
  border-bottom: 3px solid transparent;
  background: transparent;
  color: var(--color-text-muted);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition);
  font-family: var(--font-base);
  margin-bottom: -1px;
}

.tab-nav__btn:hover {
  color: var(--color-accent);
}

.tab-nav__btn.is-active {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

.tab-nav__icon { font-size: 1rem; }

/* ----- Tab Panels ----- */
.tab-panels { padding: 32px 0; }

.tab-panel { display: none; }
.tab-panel.is-active { display: block; }

/* ----- Card ----- */
.card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition);
}

.card:hover { box-shadow: var(--shadow-hover); }

.card__title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: 8px;
}

.card__meta {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: 12px;
}

.card__body {
  font-size: 0.9375rem;
  line-height: 1.7;
}

/* ----- Grid ----- */
.grid { display: grid; gap: 20px; }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

/* ----- Signal Tab ----- */
.signal-summary {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin-bottom: 28px;
}

.signal-stat {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
  text-align: center;
  box-shadow: var(--shadow-card);
}

.signal-stat__label {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: 6px;
}

.signal-stat__value {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--color-accent);
  letter-spacing: -0.02em;
}

.signal-stat__sub {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-top: 4px;
}

.chart-wrap {
  position: relative;
  height: 320px;
}

/* ----- Badge ----- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge--accent   { background: rgba(83,74,183,0.1); color: var(--color-accent); }
.badge--positive { background: rgba(22,163,74,0.1);  color: #16a34a; }
.badge--negative { background: rgba(220,38,38,0.1);  color: #dc2626; }
.badge--neutral  { background: rgba(107,107,138,0.1); color: var(--color-text-muted); }

/* ----- Glossary ----- */
.glossary-item {
  padding: 20px 0;
  border-bottom: 1px solid var(--color-border);
}

.glossary-item:last-child { border-bottom: none; }

.glossary-item__term {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: 4px;
}

.glossary-item__term-en {
  font-size: 0.875rem;
  color: var(--color-accent);
  margin-bottom: 8px;
}

.glossary-item__def {
  font-size: 0.9375rem;
  color: var(--color-dark);
  line-height: 1.7;
}

/* ----- Calendar ----- */
.calendar-event {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--color-border);
}

.calendar-event:last-child { border-bottom: none; }

.calendar-event__date {
  flex-shrink: 0;
  width: 52px;
  text-align: center;
  background: rgba(83,74,183,0.06);
  border-radius: var(--radius-sm);
  padding: 8px 4px;
}

.calendar-event__day   { font-size: 1.375rem; font-weight: 800; color: var(--color-accent); line-height: 1; }
.calendar-event__month { font-size: 0.75rem;  color: var(--color-text-muted); margin-top: 2px; }

.calendar-event__body  { flex: 1; }
.calendar-event__title { font-weight: 600; font-size: 0.9375rem; margin-bottom: 4px; }
.calendar-event__desc  { font-size: 0.875rem; color: var(--color-text-muted); }

/* ----- Learn Tab ----- */
.learn-card {
  display: flex;
  flex-direction: column;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition);
}

.learn-card:hover { box-shadow: var(--shadow-hover); }

.learn-card__thumb {
  height: 140px;
  background: linear-gradient(135deg, var(--color-accent) 0%, #7B74D4 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
}

.learn-card__body { padding: 20px; flex: 1; }
.learn-card__title { font-weight: 700; margin-bottom: 8px; }
.learn-card__desc  { font-size: 0.875rem; color: var(--color-text-muted); }

/* ----- Button ----- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  border: none;
  font-family: var(--font-base);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
}

.btn--primary {
  background: var(--color-accent);
  color: var(--color-white);
}

.btn--primary:hover {
  background: var(--color-accent-hover);
  color: var(--color-white);
}

.btn--outline {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-dark);
}

.btn--outline:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ----- Section Title ----- */
.section-title {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.section-title::before {
  content: "";
  display: block;
  width: 4px;
  height: 1.25em;
  background: var(--color-accent);
  border-radius: 2px;
}

/* ----- Site Footer ----- */
.site-footer {
  background: var(--color-white);
  border-top: 1px solid var(--color-border);
  padding: 32px 0;
  margin-top: 48px;
}

.site-footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.site-footer__copy {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* ----- News Card ----- */
.news-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.news-card {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow-card);
  transition: border-color var(--transition), box-shadow var(--transition);
  cursor: default;
}

.news-card:hover {
  border-color: #AFA9EC;
  box-shadow: var(--shadow-hover);
}

.news-card__icon {
  flex-shrink: 0;
  width: 80px;
  height: 80px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
}

.news-card__body {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.news-card__cat {
  display: inline-flex;
  align-items: center;
  padding: 2px 10px;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
  align-self: flex-start;
}

.news-card__title {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--color-dark);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.news-card__meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 2px;
}

.news-card__source {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  font-weight: 500;
}

.news-card__date {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.news-card__source::after {
  content: "·";
  margin-left: 10px;
}

/* ----- Responsive ----- */
@media (max-width: 1024px) {
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .news-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .container { padding: 0 16px; }
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }
  .tab-nav__btn { padding: 12px 14px; font-size: 0.8125rem; }
  .tab-panels { padding: 20px 0; }
  .card { padding: 18px; }
  .site-header__inner { height: 56px; }
  .site-footer__inner { flex-direction: column; text-align: center; }

  /* News card: compact on mobile */
  .news-grid { gap: 12px; }
  .news-card { padding: 14px; gap: 12px; }
  .news-card__icon { width: 60px; height: 60px; }
  .news-card__icon svg { width: 28px; height: 28px; }
  .news-card__title { font-size: 0.875rem; }
}

@media (max-width: 480px) {
  .signal-summary { grid-template-columns: repeat(2, 1fr); }
  .signal-stat__value { font-size: 1.375rem; }
}