/* Straumann Campus — Impeccable Design System */
/* Sharp, Flat, Functional — Global Standards First */

:root {
  /* CORRECTED Design Tokens — Sharp & Flat */
  --color-primary: #007664;          /* Actual Straumann Teal */
  --color-primary-dark: #005a4a;     /* hover states */
  --color-primary-light: #e6f4f1;    /* background emphasis */
  --brand-navy: #003b5c;             /* footer, secondary */

  --color-text: #1f2937;
  --color-text-secondary: #6b7280;
  --color-bg: #ffffff;
  --color-bg-light: #f8f9fa;
  --color-border: #e1e4e8;

  /* REQUIRED: Arial font system */
  --font-main: 'Arial', 'Noto Sans KR', sans-serif;

  /* CRITICAL: Sharp corners everywhere */
  --radius-sm: 0px;
  --radius-md: 0px;
  --radius-lg: 0px;

  /* CRITICAL: No shadows (flat design) */
  --shadow-md: none;
  --shadow-sm: none;
  --shadow-lg: none;

  /* Spacing scale — 4pt system */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 12px;
  --space-lg: 16px;
  --space-xl: 24px;
  --space-2xl: 32px;
  --space-3xl: 48px;

  /* Status colors (flat, no variations) */
  --status-success: #10b981;
  --status-warning: #f59e0b;
  --status-error: #ef4444;
  --status-info: #3b82f6;

  /* Neutral scale (tinted toward teal) */
  --neutral-50: #f9fafb;
  --neutral-100: #f3f4f6;
  --neutral-200: #e5e7eb;
  --neutral-300: #d1d5db;
  --neutral-400: #9ca3af;
  --neutral-500: #6b7280;
  --neutral-600: #4b5563;
  --neutral-700: #374151;
  --neutral-800: #1f2937;
  --neutral-900: #111827;
}

/* Global Reset — Sharp Edges */
* {
  box-sizing: border-box;
  border-radius: 0 !important; /* ENFORCE sharp corners */
}

body {
  font-family: var(--font-main);
  background-color: var(--neutral-50);
  color: var(--neutral-900);
  margin: 0;
  padding: 0;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

body.str-sidebar-open {
  overflow: hidden;
}

input,
button,
select,
textarea {
  font: inherit;
}

/* Navigation — Flat & Sharp */
.navbar {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border); /* NO shadow */
  position: sticky;
  top: 0;
  z-index: 100;
  height: 70px;
  display: flex;
  align-items: center;
}

.navbar .container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.navbar-brand a {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--brand-navy);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.navbar-menu {
  display: flex;
  gap: var(--space-2xl);
}

.navbar-menu a {
  color: var(--neutral-600);
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  transition: color 0.2s ease;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.navbar-menu a:hover,
.navbar-menu a.active {
  color: var(--color-primary);
}

/* Main Layout — Left Sidebar + Right Grid */
.str-page {
  min-height: calc(100vh - 70px);
  background: var(--neutral-50);
}

.str-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: var(--space-xl);
}

.str-page-subtitle {
  margin: 0 0 var(--space-md);
  color: var(--neutral-600);
  font-size: 0.95rem;
  line-height: 1.6;
}

.str-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-3xl);
  align-items: start;
}

/* LEFT SIDEBAR — Sharp Accordions */
.str-sidebar {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  padding: var(--space-xl);
  position: sticky;
  top: 90px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
}

.str-filter-toggle {
  display: none;
  background: var(--color-primary);
  color: white;
  border: none;
  padding: var(--space-md) var(--space-lg);
  font-family: var(--font-main);
  font-weight: 600;
  cursor: pointer;
  margin-bottom: var(--space-lg);
  transition: background-color 0.2s ease;
}

.str-filter-toggle:hover {
  background: var(--color-primary-dark);
}

/* Search Control */
.str-search-control {
  display: flex;
  margin-bottom: var(--space-xl);
}

.str-search-input {
  flex: 1;
  padding: var(--space-md);
  border: 1px solid var(--color-border);
  font-family: var(--font-main);
  font-size: 1rem;
}

.str-search-input:focus {
  outline: none;
  border-color: var(--color-primary);
}

.str-search-btn {
  background: var(--color-primary);
  color: white;
  border: none;
  padding: var(--space-md) var(--space-lg);
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.str-search-btn:hover {
  background: var(--color-primary-dark);
}

/* Accordion Sections — Sharp & Functional */
.str-accordion {
  border: 1px solid var(--color-border);
  margin-bottom: var(--space-lg);
}

.str-accordion-header {
  background: var(--neutral-100);
  padding: var(--space-md) var(--space-lg);
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--color-border);
}

.str-accordion-header:hover {
  background: var(--neutral-200);
}

.str-accordion-body {
  padding: var(--space-lg);
  background: var(--color-bg);
}

/* Checkbox Controls — Sharp Design */
.str-radio {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
  cursor: pointer;
  font-size: 0.9rem;
  line-height: 1.4;
}

.str-radio input[type="checkbox"] {
  display: none;
}

.str-radio-box {
  width: 16px;
  height: 16px;
  border: 2px solid var(--color-border);
  background: var(--color-bg);
  position: relative;
  flex-shrink: 0;
}

.str-radio input[type="checkbox"]:checked + .str-radio-box {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.str-radio input[type="checkbox"]:checked + .str-radio-box::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: white;
  font-size: 12px;
  font-weight: bold;
}

/* RIGHT CONTENT — Grid System */
.str-main {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  padding: var(--space-xl);
}

.str-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-xl);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

.str-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--neutral-900);
  margin: 0;
  line-height: 1.35;
}

.str-count {
  color: var(--neutral-600);
  font-size: 1rem;
}

/* Seminar Grid — Sharp Cards */
.str-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: var(--space-2xl);
}

.str-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  transition: border-color 0.2s ease;
  cursor: pointer;
  overflow: hidden;
}

.str-card:hover {
  border-color: var(--color-primary);
}

.str-card-img-box {
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--neutral-100);
  position: relative;
}

.str-card-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.str-card-placeholder {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: var(--neutral-400);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: 2px;
}

.str-card-body {
  padding: var(--space-xl);
}

/* Status Badge — Flat Design */
.str-card-status {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  background: var(--color-primary-light);
  color: var(--color-primary);
  padding: 8px var(--space-md);
  font-size: 0.95rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: var(--space-lg);
  border: 1px solid var(--color-primary);
}

/* Typography — Clear Hierarchy */
.str-card-title {
  margin: 0 0 var(--space-lg) 0;
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.str-card-title a {
  color: var(--neutral-900);
  text-decoration: none;
  transition: color 0.2s ease;
}

.str-card-title a:hover {
  color: var(--color-primary);
}

/* Metadata — Structured Info */
.str-card-meta {
  margin-bottom: var(--space-lg);
}

.str-card-meta span {
  display: block;
  color: var(--neutral-600);
  font-size: 0.92rem;
  margin-bottom: var(--space-xs);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  line-height: 1.55;
}

.str-card-meta i {
  width: 16px;
  color: var(--neutral-400);
}

/* Instructor Info */
.str-card-instructor {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
}

.str-avatar {
  width: 32px;
  height: 32px;
  background: var(--neutral-200);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--neutral-500);
}

.str-instructor-name {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--neutral-700);
}

/* Pagination — Sharp Buttons */
.str-pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-sm);
  margin-top: var(--space-3xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border);
}

.str-pagination a,
.str-pagination span {
  padding: var(--space-sm) var(--space-lg);
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--neutral-700);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.2s ease;
}

.str-pagination a:hover {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

.str-pagination .current {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

/* Empty State — Clear Messaging */
.str-empty {
  text-align: center;
  padding: var(--space-3xl);
  color: var(--neutral-600);
}

.str-empty p {
  font-size: 1.125rem;
  margin-bottom: var(--space-xl);
}

/* Buttons — Sharp & Functional */
.str-btn {
  display: inline-block;
  padding: var(--space-md) var(--space-xl);
  background: var(--color-primary);
  color: white;
  text-decoration: none;
  font-weight: 600;
  font-family: var(--font-main);
  border: none;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.str-btn:hover {
  background: var(--color-primary-dark);
}

.str-btn-secondary {
  background: var(--neutral-200);
  color: var(--neutral-700);
  border: 1px solid var(--color-border);
}

.str-btn-secondary:hover {
  background: var(--neutral-300);
}

/* Mobile Responsive */
@media (max-width: 1024px) {
  .str-layout {
    grid-template-columns: 1fr;
    gap: 16px;
  }
}

/* Mobile Responsive — Comprehensive */
@media (max-width: 768px) {
  :root {
    --space-lg: 14px;
    --space-xl: 20px;
    --space-2xl: 24px;
  }

  /* Navbar mobile menu toggle */
  .navbar .container {
    padding: 0 16px;
    position: relative;
  }

  .mobile-menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: transparent;
    border: 1px solid var(--color-border);
    font-size: 1.25rem;
    color: var(--brand-navy);
    cursor: pointer;
  }

  .navbar-menu {
    display: none;
    flex-direction: column;
    width: 100%;
    background: white;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    padding: 16px;
    z-index: 1000;
    border-bottom: 1px solid var(--color-border);
    border-top: 1px solid var(--color-border);
    gap: 0;
  }

  .navbar-menu.active {
    display: flex;
  }

  .navbar-menu a {
    padding: 14px 16px;
    border-bottom: 1px solid var(--color-border);
    width: 100%;
    font-size: 1rem;
  }

  .navbar-menu a:last-child {
    border-bottom: none;
  }

  .navbar-menu a:hover,
  .navbar-menu a.active {
    background: var(--color-primary-light);
    color: var(--color-primary);
  }

  /* Page container */
  .str-container {
    padding: 0 16px;
  }

  .str-page {
    padding-bottom: 88px;
  }

  /* Card body */
  .str-card-body {
    padding: 18px 16px 16px;
  }

  /* Grid: single column */
  .str-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* Main content area */
  .str-main {
    padding: 18px 16px;
  }

  /* Page title */
  .str-page-title,
  .str-title {
    font-size: 1.35rem;
    line-height: 1.4;
    letter-spacing: -0.01em;
  }

  .str-page-subtitle {
    font-size: 0.9rem;
    margin-bottom: 12px;
  }

  /* Results bar */
  .str-results-bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  /* Card meta */
  .str-card-meta span {
    font-size: 0.9rem;
  }

  /* Card status */
  .str-card-status {
    font-size: 0.7rem;
  }

  /* Card title */
  .str-card-title {
    font-size: 1.1rem;
    line-height: 1.45;
  }

  /* Search input - prevent iOS zoom */
  .str-search-input {
    font-size: 16px;
    padding: 13px 14px;
  }

  .str-search-btn {
    width: 48px;
  }

  /* Accordion header */
  .str-accordion-header {
    padding: 12px 14px;
    font-size: 0.875rem;
  }

  /* Filter toggle */
  .str-filter-toggle {
    display: block;
    width: 100%;
    padding: 14px 16px;
    font-size: 0.95rem;
  }

  .str-filter-backdrop {
    position: fixed;
    inset: 70px 0 0;
    background: rgba(17, 24, 39, 0.35);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
    z-index: 190;
  }

  .str-filter-backdrop.show {
    opacity: 1;
    visibility: visible;
  }

  /* Sidebar when shown on mobile */
  .str-sidebar {
    display: none;
  }

  .str-sidebar.show {
    display: block;
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 200;
    overflow-y: auto;
    padding: 16px;
    border: none;
    border-top: 1px solid var(--color-border);
    background: var(--color-bg);
    max-height: none;
  }

  /* Pagination */
  .str-pagination {
    flex-wrap: wrap;
  }

  /* Footer responsive */
  .main-footer {
    padding: 32px 0 24px;
  }
  .main-footer .inner_container {
    padding: 0 16px;
  }
  .f-top-box {
    gap: 20px;
    flex-direction: column;
  }
  .f-info {
    font-size: 13px;
  }
  .foot_company {
    font-size: 13px;
  }
}

@media (max-width: 480px) {
  .str-container {
    padding: 0 12px;
  }

  .str-card-body {
    padding: 12px;
  }

  .str-page-title,
  .str-title {
    font-size: 1.2rem;
  }

  .str-card-title {
    font-size: 1rem;
  }

  .navbar-menu a {
    padding: 12px 14px;
    font-size: 0.95rem;
  }
}

/* CRITICAL: Remove any lingering rounded corners */
input, button, select, textarea,
.str-card, .str-sidebar, .str-accordion,
.str-radio-box, .str-btn, .str-card-img-box {
  border-radius: 0 !important;
}

/* CRITICAL: Remove any shadows */
.navbar, .str-sidebar, .str-card, .str-btn {
  box-shadow: none !important;
}