/* =========================================================
   Level-1-JS-Interactivity — Styles
   Codveda brand palette, mobile-first, semantic layout
   ========================================================= */

/* ---------- CSS Custom Properties ---------- */
:root {
  --color-primary: #2563eb;
  --color-primary-dark: #103eb2;
  --color-primary-light: #7296f2;
  --color-navy: #1b1f29;
  --color-navy-deep: #141720;
  --color-surface: #f9fbff;
  --color-white: #ffffff;
  --color-border: #e0e3eb;
  --color-text: #1b1f29;
  --color-text-secondary: #4b4f58;
  --color-gold: #fcb900;
  --color-red: #cf2e2e;
  --color-success: #00d084;

  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --shadow-xl: 0 16px 50px rgba(0,0,0,0.15);

  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
}

/* ---------- Reset & Base ---------- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:'Inter',system-ui,-apple-system,sans-serif;
  font-size:1rem;line-height:1.6;
  color:var(--color-text);background:var(--color-surface);
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:var(--color-primary);text-decoration:none}
button{cursor:pointer;font:inherit}
ul,ol{list-style:none}
input,textarea,select,button{font:inherit}

.sr-only{
  position:absolute;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0,0,0,0);border:0;white-space:nowrap;
}

/* ---------- Container ---------- */
.container{width:100%;max-width:900px;margin:0 auto;padding:0 var(--space-lg)}

/* ---------- Navigation ---------- */
.site-nav{
  position:fixed;top:0;left:0;right:0;z-index:100;
  background:rgba(255,255,255,0.92);backdrop-filter:blur(12px);
  border-bottom:1px solid var(--color-border);
}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:60px}
.nav-logo{font-weight:700;font-size:1.15rem;color:var(--color-navy)}
.nav-logo span{color:var(--color-primary)}
.nav-links{display:none;gap:var(--space-xl)}
.nav-links a{font-size:0.875rem;font-weight:500;color:var(--color-text-secondary);transition:color var(--transition-fast)}
.nav-links a:hover,.nav-links a.active{color:var(--color-primary)}

.hamburger{
  display:flex;flex-direction:column;gap:5px;
  background:none;border:none;padding:6px;
}
.hamburger span{width:22px;height:2px;background:var(--color-navy);border-radius:2px;transition:var(--transition-base)}
.hamburger.open span:nth-child(1){transform:rotate(45deg) translate(5px,5px)}
.hamburger.open span:nth-child(2){opacity:0}
.hamburger.open span:nth-child(3){transform:rotate(-45deg) translate(5px,-5px)}

.mobile-overlay{display:none;position:fixed;inset:0;z-index:98;background:rgba(0,0,0,0.3)}
.mobile-overlay.visible{display:block}

.mobile-menu{
  position:fixed;top:60px;right:0;z-index:99;
  background:var(--color-white);width:260px;padding:var(--space-lg);
  box-shadow:var(--shadow-lg);
  transform:translateX(100%);transition:transform var(--transition-base);
  display:flex;flex-direction:column;gap:var(--space-sm);
}
.mobile-menu.open{transform:translateX(0)}
.mobile-menu a{
  display:block;padding:var(--space-sm) var(--space-md);
  font-weight:500;color:var(--color-text-secondary);
  border-radius:var(--radius-sm);transition:var(--transition-fast);
}
.mobile-menu a:hover,.mobile-menu a.active{color:var(--color-primary);background:rgba(37,99,235,0.06)}

@media(min-width:768px){
  .nav-links{display:flex}
  .hamburger,.mobile-overlay,.mobile-menu{display:none!important}
}

/* ---------- Page Header ---------- */
.page-header{
  padding:calc(60px + var(--space-3xl)) 0 var(--space-3xl);
  text-align:center;
  background:linear-gradient(135deg,var(--color-navy) 0%,var(--color-navy-deep) 100%);
  color:var(--color-white);
}
.page-header h1{font-size:clamp(1.75rem,4vw,2.5rem);font-weight:700;margin-bottom:var(--space-sm)}
.page-header p{font-size:1rem;color:rgba(255,255,255,0.65);max-width:500px;margin:0 auto}

/* ---------- Section ---------- */
.section{padding:var(--space-3xl) 0}
.section-heading{font-size:clamp(1.25rem,3vw,1.75rem);font-weight:700;color:var(--color-navy);margin-bottom:var(--space-xs)}
.section-desc{font-size:0.9375rem;color:var(--color-text-secondary);margin-bottom:var(--space-xl);max-width:540px}
.section + .section{border-top:1px solid var(--color-border)}

/* ---------- Demo Card ---------- */
.demo-card{
  background:var(--color-white);border:1px solid var(--color-border);
  border-radius:var(--radius-lg);padding:var(--space-xl);box-shadow:var(--shadow-sm);
}

/* =============================================
   COMPONENT 1 — Custom Dropdown
   ============================================= */
.dropdown-wrapper{position:relative;display:inline-block;width:100%;max-width:320px}
.dropdown-trigger{
  width:100%;display:flex;align-items:center;justify-content:space-between;
  padding:0.7rem 1rem;
  background:var(--color-white);border:1.5px solid var(--color-border);
  border-radius:var(--radius-md);font-size:0.9375rem;color:var(--color-text);
  transition:border-color var(--transition-fast),box-shadow var(--transition-fast);
}
.dropdown-trigger:hover{border-color:var(--color-primary-light)}
.dropdown-trigger:focus,.dropdown-trigger[aria-expanded="true"]{
  border-color:var(--color-primary);box-shadow:0 0 0 3px rgba(37,99,235,0.12);outline:none;
}
.dropdown-trigger svg{width:16px;height:16px;color:var(--color-text-secondary);transition:transform var(--transition-fast)}
.dropdown-trigger[aria-expanded="true"] svg{transform:rotate(180deg)}

.dropdown-menu{
  position:absolute;top:calc(100% + 6px);left:0;right:0;z-index:50;
  background:var(--color-white);border:1px solid var(--color-border);
  border-radius:var(--radius-md);padding:var(--space-xs) 0;
  box-shadow:var(--shadow-lg);
  opacity:0;transform:translateY(-8px);pointer-events:none;
  transition:opacity var(--transition-fast),transform var(--transition-fast);
}
.dropdown-menu.open{opacity:1;transform:translateY(0);pointer-events:auto}
.dropdown-menu li{
  padding:0.55rem 1rem;font-size:0.9375rem;color:var(--color-text);
  cursor:pointer;transition:background var(--transition-fast);
}
.dropdown-menu li:hover,.dropdown-menu li:focus{background:rgba(37,99,235,0.06);color:var(--color-primary);outline:none}
.dropdown-menu li[aria-selected="true"]{color:var(--color-primary);font-weight:600}
.dropdown-selected{margin-top:var(--space-sm);font-size:0.8125rem;color:var(--color-text-secondary);min-height:1.3em}

/* =============================================
   COMPONENT 2 — Modal Dialog
   ============================================= */
.modal-trigger{
  display:inline-flex;align-items:center;gap:var(--space-sm);
  padding:0.7rem 1.5rem;background:var(--color-primary);color:var(--color-white);
  border:none;border-radius:var(--radius-md);font-weight:600;font-size:0.9375rem;
  transition:background var(--transition-fast),transform var(--transition-fast);
}
.modal-trigger:hover{background:var(--color-primary-dark)}
.modal-trigger:active{transform:scale(0.97)}

.modal-backdrop{
  position:fixed;inset:0;z-index:200;
  display:none;align-items:center;justify-content:center;
  background:rgba(27,31,41,0.55);
  backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);
  padding:var(--space-lg);
}
.modal-backdrop.visible{display:flex}

.modal{
  background:var(--color-white);border-radius:var(--radius-xl);
  padding:var(--space-2xl);max-width:480px;width:100%;
  box-shadow:var(--shadow-xl);position:relative;
  animation:modal-enter 0.3s ease forwards;
}
@keyframes modal-enter{
  from{opacity:0;transform:translateY(20px) scale(0.96)}
  to{opacity:1;transform:translateY(0) scale(1)}
}
.modal-close{
  position:absolute;top:var(--space-md);right:var(--space-md);
  background:none;border:none;padding:var(--space-xs);
  color:var(--color-text-secondary);border-radius:var(--radius-sm);
  transition:color var(--transition-fast),background var(--transition-fast);
}
.modal-close:hover{color:var(--color-red);background:rgba(207,46,46,0.06)}
.modal-close svg{width:20px;height:20px}
.modal h3{font-size:1.25rem;font-weight:700;color:var(--color-navy);margin-bottom:var(--space-sm)}
.modal p{font-size:0.9375rem;color:var(--color-text-secondary);line-height:1.65;margin-bottom:var(--space-lg)}
.modal-actions{display:flex;gap:var(--space-sm);justify-content:flex-end}
.modal-actions button{
  padding:0.55rem 1.25rem;border-radius:var(--radius-md);
  font-weight:600;font-size:0.875rem;border:none;transition:background var(--transition-fast);
}
.btn-cancel{background:transparent;color:var(--color-text-secondary)}
.btn-cancel:hover{background:rgba(0,0,0,0.04)}
.btn-confirm{background:var(--color-primary);color:var(--color-white)}
.btn-confirm:hover{background:var(--color-primary-dark)}

/* =============================================
   COMPONENT 3 — Form Validation
   ============================================= */
.validated-form{max-width:480px}
.form-group{margin-bottom:var(--space-lg)}
.form-group label{
  display:block;font-size:0.8125rem;font-weight:600;
  color:var(--color-navy);margin-bottom:var(--space-xs);letter-spacing:0.02em;
}
.form-group label .required{color:var(--color-red);margin-left:2px}
.form-group input,.form-group textarea,.form-group select{
  width:100%;padding:0.7rem 1rem;
  border:1.5px solid var(--color-border);border-radius:var(--radius-md);
  font-size:0.9375rem;color:var(--color-text);background:var(--color-white);
  transition:border-color var(--transition-fast),box-shadow var(--transition-fast);
}
.form-group input:focus,.form-group textarea:focus{
  border-color:var(--color-primary);box-shadow:0 0 0 3px rgba(37,99,235,0.12);outline:none;
}
.form-group textarea{resize:vertical;min-height:100px}
.form-group input.error,.form-group textarea.error{
  border-color:var(--color-red);box-shadow:0 0 0 3px rgba(207,46,46,0.1);
}
.form-group input.valid,.form-group textarea.valid{
  border-color:var(--color-success);box-shadow:0 0 0 3px rgba(0,208,132,0.1);
}
.error-message{display:block;font-size:0.75rem;color:var(--color-red);margin-top:4px;min-height:1rem;line-height:1.4}
.char-count{display:block;text-align:right;font-size:0.75rem;color:var(--color-text-secondary);margin-top:2px}
.char-count.warn{color:var(--color-gold)}
.char-count.over{color:var(--color-red)}

.form-submit{
  width:100%;padding:0.75rem;background:var(--color-primary);color:var(--color-white);
  border:none;border-radius:var(--radius-md);font-weight:600;font-size:0.9375rem;
  transition:background var(--transition-fast),transform var(--transition-fast);
}
.form-submit:hover:not(:disabled){background:var(--color-primary-dark)}
.form-submit:active:not(:disabled){transform:scale(0.98)}
.form-submit:disabled{opacity:0.5;cursor:not-allowed}

.form-success{
  display:none;padding:var(--space-lg);
  background:rgba(0,208,132,0.08);border:1px solid rgba(0,208,132,0.25);
  border-radius:var(--radius-md);color:var(--color-navy);font-weight:500;text-align:center;
}
.form-success.visible{display:block}

/* ---------- Footer ---------- */
.site-footer{
  text-align:center;padding:var(--space-xl) 0;
  border-top:1px solid var(--color-border);
  color:var(--color-text-secondary);font-size:0.8125rem;
}