/**
 * How It Works Page - Diagram-focused Styles
 * Extends: md3-components.css, public-common.css
 */

/* Section Styling */
.section {
  margin-bottom: 48px;
}

.section:last-child {
  margin-bottom: 0;
}

.section-title {
  font-size: 1.6rem;
  font-weight: 500;
  color: var(--md-sys-color-primary);
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--md-sys-color-outline);
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-title .material-icons {
  font-size: 1.8rem;
  color: var(--md-sys-color-primary);
}

.description {
  font-size: 1rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.7;
  margin-bottom: 24px;
}

/* Concept Highlight */
.concept-highlight {
  background: linear-gradient(135deg, var(--md-sys-color-primary-container) 0%, var(--md-sys-color-tertiary-container) 100%);
  border-radius: 16px;
  padding: 24px 32px;
  display: flex;
  align-items: center;
  gap: 20px;
  margin-top: 16px;
}

.concept-icon .material-icons {
  font-size: 3rem;
  color: var(--md-sys-color-on-primary-container);
}

.concept-text {
  font-size: 1.1rem;
  color: var(--md-sys-color-on-primary-container);
  line-height: 1.6;
}

/* Main Architecture Diagram */
.main-diagram {
  background: var(--md-sys-color-surface-2);
  border-radius: 16px;
  padding: 32px;
  margin: 24px 0;
}

.diagram-row {
  display: flex;
  justify-content: center;
}

.diagram-block {
  background: var(--md-sys-color-surface-1);
  border-radius: 12px;
  padding: 20px 32px;
  min-width: 300px;
  max-width: 500px;
  box-shadow: var(--md-sys-elevation-1);
}

.block-header {
  font-size: 1.1rem;
  font-weight: 600;
  text-align: center;
  padding-bottom: 12px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
}

.block-content {
  font-size: 0.9rem;
  color: var(--md-sys-color-on-surface-variant);
  text-align: center;
}

.block-features {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.feature-row {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--md-sys-color-on-surface);
}

.feature-row .material-icons {
  font-size: 1.2rem;
  color: var(--md-sys-color-primary);
  opacity: 0.8;
}

.fediverse-block {
  border: 2px solid var(--md-sys-color-secondary);
}

.fediverse-block .block-header {
  color: var(--md-sys-color-secondary);
}

.relay-block {
  border: 2px solid var(--md-sys-color-tertiary);
}

.relay-block .block-header {
  color: var(--md-sys-color-tertiary);
}

.mobile-block {
  border: 2px solid var(--md-sys-color-primary);
}

.mobile-block .block-header {
  color: var(--md-sys-color-primary);
}

.diagram-arrow-down {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 16px 0;
  gap: 4px;
}

.diagram-arrow-down .material-icons {
  font-size: 2rem;
  color: var(--md-sys-color-outline);
  animation: pulse 2s infinite;
}

.arrow-label {
  font-size: 0.8rem;
  color: var(--md-sys-color-on-surface-variant);
  font-family: monospace;
  background: var(--md-sys-color-surface-1);
  padding: 4px 12px;
  border-radius: 4px;
}

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

/* Why Relay Cards */
.explanation-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 16px;
  margin-top: 16px;
}

.explanation-card {
  background: var(--md-sys-color-surface-2);
  border-radius: 12px;
  padding: 20px;
  text-align: center;
}

.card-icon {
  font-size: 2.5rem;
  color: var(--md-sys-color-primary);
  margin-bottom: 12px;
}

.card-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--md-sys-color-on-surface);
  margin-bottom: 8px;
}

.card-text {
  font-size: 0.9rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.5;
}

/* Flow Diagrams (Horizontal) */
.flow-diagram {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  margin: 24px 0;
  padding: 24px;
  background: var(--md-sys-color-surface-2);
  border-radius: 12px;
  flex-wrap: wrap;
}

.flow-box {
  background: var(--md-sys-color-surface-1);
  border-radius: 12px;
  padding: 16px 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  min-width: 100px;
  box-shadow: var(--md-sys-elevation-1);
}

.flow-box .material-icons {
  font-size: 2rem;
}

.flow-box span:last-child {
  font-size: 0.85rem;
  font-weight: 500;
  text-align: center;
}

.source-box {
  border: 2px solid var(--md-sys-color-secondary);
}
.source-box .material-icons {
  color: var(--md-sys-color-secondary);
}

.relay-box {
  border: 2px solid var(--md-sys-color-tertiary);
}
.relay-box .material-icons {
  color: var(--md-sys-color-tertiary);
}

.mobile-box {
  border: 2px solid var(--md-sys-color-primary);
}
.mobile-box .material-icons {
  color: var(--md-sys-color-primary);
}

.dest-box {
  border: 2px solid var(--md-sys-color-secondary);
}
.dest-box .material-icons {
  color: var(--md-sys-color-secondary);
}

.flow-connector {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0 8px;
}

.connector-line {
  width: 50px;
  height: 3px;
  background: linear-gradient(90deg, var(--md-sys-color-outline) 0%, var(--md-sys-color-primary) 50%, var(--md-sys-color-outline) 100%);
  position: relative;
}

.connector-line::after {
  content: "";
  position: absolute;
  right: -6px;
  top: -4px;
  border: 6px solid transparent;
  border-left-color: var(--md-sys-color-primary);
}

.connector-text {
  font-size: 0.7rem;
  color: var(--md-sys-color-on-surface-variant);
  margin-top: 6px;
  font-family: monospace;
  white-space: nowrap;
}

/* Flow Steps */
.flow-steps {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 20px;
}

.step {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 12px 16px;
  background: var(--md-sys-color-surface-2);
  border-radius: 8px;
}

.step-num {
  width: 28px;
  height: 28px;
  background: var(--md-sys-color-primary);
  color: var(--md-sys-color-on-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  flex-shrink: 0;
}

.step-text {
  font-size: 0.95rem;
  color: var(--md-sys-color-on-surface);
  line-height: 1.5;
  padding-top: 2px;
}

/* Offline Diagram */
.offline-diagram {
  background: var(--md-sys-color-surface-2);
  border-radius: 12px;
  padding: 24px;
  margin: 24px 0;
}

.offline-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
}

.offline-box {
  background: var(--md-sys-color-surface-1);
  border-radius: 10px;
  padding: 16px 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  min-width: 90px;
  position: relative;
}

.offline-box .material-icons {
  font-size: 1.8rem;
}

.offline-box span:last-of-type {
  font-size: 0.8rem;
  text-align: center;
}

.offline-box.incoming {
  border: 2px solid var(--md-sys-color-secondary);
}
.offline-box.incoming .material-icons {
  color: var(--md-sys-color-secondary);
}

.offline-box.queue {
  border: 2px solid var(--md-sys-color-tertiary);
}
.offline-box.queue .material-icons {
  color: var(--md-sys-color-tertiary);
}

.offline-box.phone-offline {
  border: 2px solid var(--md-sys-color-primary);
}
.offline-box.phone-offline .material-icons {
  color: var(--md-sys-color-primary);
}

.queue-badge {
  position: absolute;
  top: -8px;
  right: -8px;
  background: var(--md-sys-color-tertiary);
  color: var(--md-sys-color-on-tertiary);
  font-size: 0.7rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 10px;
}

.offline-arrow .material-icons {
  font-size: 1.5rem;
  color: var(--md-sys-color-outline);
}

.offline-note {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  padding: 12px 16px;
  background: var(--md-sys-color-primary-container);
  border-radius: 8px;
  font-size: 0.9rem;
  color: var(--md-sys-color-on-primary-container);
}

.offline-note .material-icons {
  font-size: 1.2rem;
}

/* Security Grid */
.security-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.security-item {
  display: flex;
  gap: 16px;
  padding: 20px;
  background: var(--md-sys-color-surface-2);
  border-radius: 12px;
}

.security-icon {
  flex-shrink: 0;
}

.security-icon .material-icons {
  font-size: 2rem;
  color: var(--md-sys-color-tertiary);
}

.security-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--md-sys-color-on-surface);
  margin-bottom: 6px;
}

.security-text {
  font-size: 0.9rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.5;
}

/* Tech Badges */
.tech-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 16px 0;
}

.tech-badge {
  background: var(--md-sys-color-surface-2);
  color: var(--md-sys-color-on-surface);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid var(--md-sys-color-outline);
  transition: all 0.2s;
}

.tech-badge:hover {
  background: var(--md-sys-color-primary-container);
  color: var(--md-sys-color-on-primary-container);
  border-color: var(--md-sys-color-primary);
}

.open-source-note {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--md-sys-color-on-surface-variant);
  margin-top: 16px;
}

.open-source-note .material-icons {
  font-size: 1.1rem;
  color: var(--md-sys-color-primary);
}

/* Responsive */
@media (max-width: 768px) {
  .section-title {
    font-size: 1.4rem;
  }

  .concept-highlight {
    flex-direction: column;
    text-align: center;
  }

  .main-diagram {
    padding: 20px 16px;
  }

  .diagram-block {
    min-width: 100%;
    max-width: 100%;
  }

  .flow-diagram {
    flex-direction: column;
    gap: 8px;
  }

  .flow-connector {
    transform: rotate(90deg);
    padding: 24px 0;
  }

  .connector-line {
    width: 60px;
    height: 5px;
  }

  .connector-line::after {
    border-width: 10px;
    right: -10px;
    top: -7px;
  }

  .connector-text {
    font-size: 0.75rem;
    font-weight: 500;
    margin-top: 10px;
  }

  .offline-row {
    flex-direction: column;
    gap: 12px;
  }

  .offline-arrow {
    transform: rotate(90deg);
  }

  .explanation-cards {
    grid-template-columns: 1fr;
  }

  .security-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .flow-box {
    min-width: 80px;
    padding: 12px 16px;
  }

  .offline-box {
    min-width: 70px;
    padding: 12px 14px;
  }
}

/* Sync Diagram (Mobile <-> Relay bidirectional) */
.sync-diagram {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin: 24px 0;
  padding: 24px;
  background: var(--md-sys-color-surface-2);
  border-radius: 12px;
}

.sync-column {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.sync-box {
  background: var(--md-sys-color-surface-1);
  border-radius: 12px;
  padding: 20px 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  min-width: 100px;
  box-shadow: var(--md-sys-elevation-1);
}

.sync-box .material-icons {
  font-size: 2.5rem;
}

.sync-box span:last-child {
  font-size: 0.9rem;
  font-weight: 500;
}

.sync-arrows {
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-width: 180px;
}

.sync-arrow {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: var(--md-sys-color-surface-1);
  border-radius: 6px;
  font-size: 0.75rem;
}

.sync-arrow.right {
  justify-content: flex-end;
}

.sync-arrow.left {
  justify-content: flex-start;
}

.sync-arrow .material-icons {
  font-size: 1.2rem;
  color: var(--md-sys-color-primary);
}

.sync-arrow.left .material-icons {
  color: var(--md-sys-color-tertiary);
}

.arrow-text {
  font-family: monospace;
  color: var(--md-sys-color-on-surface-variant);
  white-space: nowrap;
}

@media (max-width: 768px) {
  .sync-diagram {
    flex-direction: column;
    gap: 16px;
  }

  .sync-arrows {
    min-width: 100%;
  }

  .sync-arrow {
    justify-content: center !important;
  }
}