/* --- Variables & Tokens --- */
:root,
:root[data-theme="light"] {
  color-scheme: light;
  /* Background Layer */
  --bg: #ebe8ef;
  --bg-l3: #ded8e6;
  /* Text */
  --text-main: #201b2b;
  --text-muted: #51465e;
  --accent-soft: color-mix(in srgb, var(--brand) 8%, transparent);
  --error-color: #831a2d;
  --error-bg: rgba(174, 34, 56, .07);
  --success-color: #064b37;
  --success-bg: rgba(9, 96, 70, .08);
  --toast-error-bg: rgba(255, 235, 235, .9);
  --toast-error-border: #ffcccc;
  --toast-error-text: #d32f2f;
  --toast-success-bg: rgba(235, 255, 240, .9);
  --toast-success-border: #ccffdd;
  --toast-success-text: #2e7d32;
  /* Glass */
  --card-bg: rgba(255, 255, 255, .60);
  --card-border: rgba(255, 255, 255, .68);
  --control-bg: rgba(255, 255, 255, .52);
  --control-border: rgba(102, 80, 123, .25);
  --glass-shadow: 0 12px 36px rgba(57, 35, 80, .10), 0 1px 4px rgba(57, 35, 80, .08);
  --dropdown-bg: #fbf9fd;
  --dropdown-hover: #eee4f1;
  --progress-track: rgba(88, 59, 107, .16);
  /* Box-Shadow */
  --icon-box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.07), inset 0 0 0 2px rgba(0, 0, 0, 0.1);
  --icon-light-opacity: 1;
  /* Scrolllbar */
  --sb-thumb-color: #8a7c96;
  --sb-thumb-hover: #6d5a7f;
}

/* Explicit Dark Theme Variables */
:root[data-theme="dark"] {
  color-scheme: dark;
  /* Background Layer */
  --bg: #0f172a;
  --bg-l3: #303c55;
  /* Text */
  --text-main: #f8f6fc;
  --text-muted: #c5c6d6;
  --accent-soft: color-mix(in srgb, var(--brand) 12%, transparent);
  --error-color: #ff9eab;
  --error-bg: rgba(255, 158, 171, .10);
  --success-color: #75e2b6;
  --success-bg: rgba(117, 226, 182, .10);
  --toast-error-bg: rgba(60, 20, 20, .9);
  --toast-error-border: #5c2b2b;
  --toast-error-text: #ff9999;
  --toast-success-bg: rgba(20, 60, 30, .9);
  --toast-success-border: #2b5c3a;
  --toast-success-text: #81c784;
  /* Glass */
  --card-bg: rgba(25, 34, 55, .74);
  --card-border: rgba(203, 213, 235, .17);
  --control-bg: rgba(6, 12, 25, .42);
  --control-border: rgba(173, 184, 213, .25);
  --glass-shadow: 0 16px 40px rgba(0, 0, 0, .30), 0 1px 4px rgba(0, 0, 0, .20);
  --dropdown-bg: #1b2337;
  --dropdown-hover: #343149;
  --progress-track: rgba(0, 0, 0, .45);
  /* Box-Shadow */
  --icon-box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.07), inset 0 0 0 2px rgba(255, 255, 255, 0.3);
  --icon-light-opacity: 0;
  /* Scrolllbar */
  --sb-thumb-color: #78849b;
  --sb-thumb-hover: #a5afc4;
}

@media (prefers-color-scheme: dark) {
:root:not([data-theme]) {
  color-scheme: dark;
  /* Background Layer */
  --bg: #0f172a;
  --bg-l3: #303c55;
  /* Text */
  --text-main: #f8f6fc;
  --text-muted: #c5c6d6;
  --accent-soft: color-mix(in srgb, var(--brand) 12%, transparent);
  --error-color: #ff9eab;
  --error-bg: rgba(255, 158, 171, .10);
  --success-color: #75e2b6;
  --success-bg: rgba(117, 226, 182, .10);
  --toast-error-bg: rgba(60, 20, 20, .9);
  --toast-error-border: #5c2b2b;
  --toast-error-text: #ff9999;
  --toast-success-bg: rgba(20, 60, 30, .9);
  --toast-success-border: #2b5c3a;
  --toast-success-text: #81c784;
  /* Glass */
  --card-bg: rgba(25, 34, 55, .74);
  --card-border: rgba(203, 213, 235, .17);
  --control-bg: rgba(6, 12, 25, .42);
  --control-border: rgba(173, 184, 213, .25);
  --glass-shadow: 0 16px 40px rgba(0, 0, 0, .30), 0 1px 4px rgba(0, 0, 0, .20);
  --dropdown-bg: #1b2337;
  --dropdown-hover: #343149;
  --progress-track: rgba(0, 0, 0, .45);
  /* Box-Shadow */
  --icon-box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.07), inset 0 0 0 2px rgba(255, 255, 255, 0.3);
  --icon-light-opacity: 0;
  /* Scrolllbar */
  --sb-thumb-color: #78849b;
  --sb-thumb-hover: #a5afc4;
}
}


/* Common Variables */
:root {
  /* Scrolllbar */
  --sb-width: 0.5vw;
  --sb-track-color: transparent;
  --accent-glow: 120deg;
  /* Brand Colors */
  --brand: #cc33cc;
  --brand2: #ed1c65;
  --brand-gradient: linear-gradient(135deg, var(--brand) 0%, var(--brand2) 100%);
  --accent: var(--brand);
  --accent-hover: var(--brand2);
  --focus-ring: color-mix(in srgb, var(--brand) 22%, transparent);
  --focus-glow: 0 0 18px var(--focus-ring);
  /* Every palette-dependent surface uses the same timing. */
  --theme-duration: .5s;
  --theme-easing: ease;
  --theme-surface-transition: background-color var(--theme-duration) var(--theme-easing),
    border-color var(--theme-duration) var(--theme-easing),
    box-shadow var(--theme-duration) var(--theme-easing),
    outline-color var(--theme-duration) var(--theme-easing);
  --theme-transition: var(--theme-surface-transition),
    color var(--theme-duration) var(--theme-easing),
    fill var(--theme-duration) var(--theme-easing),
    stroke var(--theme-duration) var(--theme-easing);
  /* Layout */
  --container-width: 1200px;
  --header-height: 80px;
  --footer-height: 80px;
}

/* --- Reset & Base --- */
html { background-color: var(--bg); transition: background-color var(--theme-duration) var(--theme-easing); }
html.theme-initializing, html.theme-initializing *, html.theme-initializing *::before, html.theme-initializing *::after { transition: none !important; }
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

*::selection {
  background: var(--brand);
  color: white;
}

/* Scrollbar */
/* width */
::-webkit-scrollbar {
  width: var(--sb-width);
}
  
/* Track */
::-webkit-scrollbar-track {
  background: none;
}
  
/* Handle */
::-webkit-scrollbar-thumb {
  background: var(--sb-thumb-color);
  transition: var(--theme-transition);
}
  
/* Handle on hover */
::-webkit-scrollbar-thumb:hover {
  background: var(--sb-thumb-hover);
}

body {
  isolation: isolate;
  font-family: 'Poppins', sans-serif;
  background: var(--bg);
  color: var(--text-main);
  line-height: 1.5;
  overflow-x: hidden;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  -webkit-text-size-adjust: 100%;
  min-height: 100vh;
  transition: var(--theme-surface-transition);
}

h1, h2, h3, h4 {
  font-family: 'Poppins', sans-serif;
  line-height: 1.2;
}

a { text-decoration: none; }

/* Ambient background; animate the color separately from the fixed gradients. */
.ambient-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -1;
  overflow: hidden;
  background-color: var(--bg);
  background-image: radial-gradient(ellipse at 0% 0%, rgba(204, 51, 204, .20), transparent 55%),
    radial-gradient(ellipse at 100% 90%, rgba(237, 28, 101, .15), transparent 55%);
  transition: var(--theme-transition);
}

/* --- Layout Utilities --- */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

.glass-panel {
  color: var(--text-main);
  background: var(--card-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--card-border);
  border-radius: 28px;
  box-shadow: var(--glass-shadow);
  transition: var(--theme-surface-transition);
}

/* Rounded radii remain the fallback when corner-shape is unavailable. */
.glass-panel, .contact-link, .icon-box, .error-banner,
.form-input, .drop-zone, .file-item, .checkmark, .btn-submit, .btn-remove-file,
.lang-btn, .slider, .dropdown-menu, .dropdown-item, .subject-options, .subject-option,
.file-progress-bg, .file-progress-fill {
  corner-shape: squircle;
}

/* --- Header --- */
header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 100;
  background: var(--card-bg);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--card-border);
  transition: var(--theme-surface-transition);
}

.nav-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.logo {
  width: 192px;
  height: auto;
}

/* --- Theme Switcher --- */
.switch {
  display: inline-block;
  position: relative;
  width: 3em;
  height: 1.75em;
}

/* Hide default HTML checkbox */
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

/* The slider */
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--control-bg);
  border-radius: 24px;
  border: 1px solid var(--control-border);
  transition: var(--theme-transition);
}

.slider::before, .slider::after {
  position: absolute;
  content: "";
  height: 1.1em;
  width: 1.1em;
  border-radius: 50%;
  left: 0.4em;
  top: 50%;
  transform: translateY(-50%);
  transition: left var(--theme-duration) var(--theme-easing), opacity var(--theme-duration) var(--theme-easing);
}

.slider::before {
  background: linear-gradient(40deg, #ff0080, #ff8c00 70%);
  box-shadow: 0 2px 4px rgba(0,0,0,0.2);
  opacity: 1;
}

.slider::after {
  background: transparent;
  box-shadow: inset -2px -2px 0 -1.5px #8983f7, inset -6px -3px 0 0 #a3dafb;
  opacity: 0;
}

input:checked + .slider::before, input:checked + .slider::after { left: calc(100% - (1.1em + 0.4em)); }
input:checked + .slider::before { opacity: 0; }
input:checked + .slider::after { opacity: 1; }

/* --- Language Dropdown --- */
.lang-dropdown {
  position: relative;
}

/* Keep the hidden menu's palette current when the theme changes.
   Native details otherwise skips rendering its closed content. */
.lang-dropdown::details-content {
  content-visibility: visible;
}

.lang-btn {
  background: var(--control-bg);
  border: 1px solid var(--control-border);
  color: var(--text-main);
  padding: 0 16px;
  height: 44px;
  border-radius: 24px;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: var(--theme-transition);
}

.lang-btn .fa-chevron-down {
  transition: transform .5s cubic-bezier(.4, 0, .2, 1);
}
.lang-dropdown[open] .lang-btn .fa-chevron-down { transform: rotate(180deg); }

.dropdown-menu {
  color: var(--text-main);
  position: absolute;
  top: calc(100% + 8px);
  background: var(--dropdown-bg);
  border: 1px solid var(--control-border);
  border-radius: 20px;
  padding: 8px;
  min-width: 120px;
  box-shadow: var(--glass-shadow);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(-10px);
  transition: var(--theme-surface-transition), opacity .5s cubic-bezier(.4, 0, .2, 1), transform .5s cubic-bezier(.4, 0, .2, 1), visibility 0s .5s;
  z-index: 101;
}

.dropdown-menu.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  pointer-events: auto;
  transition-delay: 0s;
}

.dropdown-item {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 10px 12px;
  border: none;
  background: transparent;
  color: var(--text-main);
  border-radius: 12px;
  cursor: pointer;
  text-align: left;
  text-decoration: none;
  font-size: 0.9rem;
  font-family: 'Poppins', sans-serif;
  font-weight: 400;
  transition: var(--theme-transition);
}

.dropdown-item:hover {
  background: var(--dropdown-hover);
}

.dropdown-item.active {
  color: var(--accent);
  background: var(--accent-soft);
}

/* --- Footer --- */
#footer {
  padding: 40px 0;
  text-align: center;
  color: var(--text-muted);
  border-top: 1px solid var(--card-border);
  font-size: 0.9rem;
  background: var(--card-bg);
  transition: var(--theme-surface-transition);
}
#footer p { color: var(--text-muted); transition: var(--theme-transition); }

.social-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 20px;
}

.social-links a {
  color: var(--text-main);
  font-size: 1.2rem;
  transition: var(--theme-transition);
}

.social-links a:hover {
  color: var(--accent);
}

.legal-link {
  color: var(--text-muted);
  font-size: 1em;
  text-decoration: none;
  margin: 0 10px;
  transition: var(--theme-transition);
}
.legal-link:hover { color: var(--accent-hover); }
/* Progressive enhancement and keyboard focus */
[hidden] { display: none !important; }
.js-only { display: none; }
.theme-ready .js-only { display: inline-block; }
.header-actions { display: flex; gap: 15px; align-items: center; }
.lang-btn { list-style: none; }
.lang-btn::-webkit-details-marker { display: none; }
.lang-dropdown[open] .dropdown-menu { opacity: 1; visibility: visible; transform: translateY(0); pointer-events: auto; transition-delay: 0s; }
:focus-visible { outline: none; box-shadow: var(--focus-glow); }
a:focus-visible { color: var(--accent); background-color: var(--accent-soft); }
.lang-btn:focus-visible,
.switch input:focus-visible + .slider { outline: none; border-color: var(--accent); box-shadow: var(--focus-glow); }
@media (max-width: 420px) {
  .nav-inner { padding-left: 16px; padding-right: 16px; }
  .header-actions { gap: 10px; }
  .logo { width: clamp(112px, calc(100vw - 208px), 192px); }
  .lang-btn { padding-left: 12px; padding-right: 12px; }
}
@media (prefers-reduced-motion: reduce) {
  :root { --theme-duration: 0s; }
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}