/* ============================================================
   Water Intake Calculator — Custom Styles
   ============================================================ */

:root {
  --bg-start: #F0F4FF;
  --bg-end: #E8F5E9;
  --accent: #4A90D9;
  --accent-dark: #2e6fb5;
  --text-primary: #2d3748;
  --text-secondary: #718096;
  --card-bg: #ffffff;
  --card-shadow: 0 4px 24px rgba(74, 144, 217, 0.10);
  --radius: 12px;
  --transition: 0.3s ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: linear-gradient(135deg, var(--bg-start) 0%, var(--bg-end) 100%);
  min-height: 100vh;
  color: var(--text-primary);
  line-height: 1.6;
}

/* ---- Typography ---- */
h1 { font-size: clamp(1.6rem, 4vw, 2.4rem); font-weight: 800; color: var(--text-primary); }
h2 { font-size: clamp(1.2rem, 3vw, 1.6rem); font-weight: 700; }
h3 { font-size: 1.1rem; font-weight: 600; }

/* ---- Layout ---- */
.container { max-width: 860px; margin: 0 auto; padding: 0 1rem; }
.section-gap { margin-top: 2rem; }

/* ---- Card ---- */
.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  padding: 1.75rem;
  transition: box-shadow var(--transition);
}
.card:hover { box-shadow: 0 8px 32px rgba(74, 144, 217, 0.16); }

/* ---- Navigation ---- */
.site-nav {
  background: #fff;
  box-shadow: 0 1px 8px rgba(0,0,0,0.06);
  position: sticky;
  top: 0;
  z-index: 50;
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 1rem;
}
.nav-brand {
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--accent);
  text-decoration: none;
}
.nav-links {
  display: flex;
  gap: 1.25rem;
}
.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  transition: color var(--transition);
}
.nav-links a:hover, .nav-links a.active {
  color: var(--accent);
}

/* ---- Header ---- */
header {
  background: linear-gradient(135deg, #4A90D9 0%, #56b4e0 100%);
  color: white;
  padding: 2rem 1rem 2.5rem;
  text-align: center;
}
header h1 { color: white; margin-bottom: 0.5rem; }
header p { opacity: 0.92; font-size: 1.05rem; }

/* ---- Ad Banners ---- */
.ad-banner {
  text-align: center;
  padding: 0.5rem 0;
  min-height: 52px;
  overflow: hidden;
}

/* ---- Form ---- */
.form-group { margin-bottom: 1.25rem; }
.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
  font-size: 0.95rem;
  color: var(--text-primary);
}
.form-input, .form-select {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 2px solid #e2e8f0;
  border-radius: 8px;
  font-size: 1rem;
  color: var(--text-primary);
  background: #fafbff;
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
  -webkit-appearance: none;
  appearance: none;
}
.form-input:focus, .form-select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(74, 144, 217, 0.18);
}
.form-select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%234A90D9' stroke-width='2' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  padding-right: 2.5rem;
}
.error-msg {
  color: #e53e3e;
  font-size: 0.85rem;
  margin-top: 0.3rem;
}

/* ---- Unit Toggle ---- */
.unit-toggle {
  display: inline-flex;
  border: 2px solid var(--accent);
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 1rem;
}
.unit-toggle button {
  padding: 0.45rem 1.2rem;
  font-size: 0.9rem;
  font-weight: 600;
  background: transparent;
  color: var(--accent);
  border: none;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}
.unit-toggle button.active {
  background: var(--accent);
  color: white;
}

/* ---- CTA Button ---- */
.btn-primary {
  display: block;
  width: 100%;
  padding: 1rem;
  background: linear-gradient(135deg, #4A90D9 0%, #56b4e0 100%);
  color: white;
  font-size: 1.1rem;
  font-weight: 700;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition);
  letter-spacing: 0.02em;
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(74, 144, 217, 0.35);
}
.btn-primary:active { transform: translateY(0); }

/* ---- Result Card ---- */
.result-highlight {
  display: flex;
  gap: 1.5rem;
  align-items: center;
  flex-wrap: wrap;
  margin: 1rem 0;
}
.result-big {
  flex: 1;
  min-width: 120px;
  text-align: center;
  background: linear-gradient(135deg, #EBF8FF 0%, #E0F4FF 100%);
  border-radius: var(--radius);
  padding: 1rem;
}
.result-big .num {
  display: block;
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1.1;
}
.result-big .lbl {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.2rem;
}

/* ---- Share Buttons ---- */
.share-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}
.btn-share {
  flex: 1;
  min-width: 100px;
  padding: 0.6rem 0.8rem;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform var(--transition), opacity var(--transition);
}
.btn-share:hover { transform: translateY(-1px); opacity: 0.9; }
.btn-twitter { background: #1da1f2; color: white; }
.btn-whatsapp { background: #25d366; color: white; }
.btn-copy { background: var(--accent); color: white; }

/* ---- Cup Grid ---- */
#cup-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(58px, 1fr));
  gap: 0.75rem;
  margin: 1.25rem 0;
}

.cup {
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0.35rem;
  border-radius: 8px;
  color: #a0aec0;
  transition: color var(--transition), background var(--transition), transform 0.15s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}
.cup:hover { background: #EBF8FF; color: var(--accent); transform: scale(1.08); }
.cup svg { width: 44px; height: 54px; }
.cup .cup-fill { transition: opacity 0.4s ease; opacity: 0; }
.cup .cup-check { transition: opacity 0.3s ease 0.15s; opacity: 0; }

.cup.filled { color: var(--accent); }
.cup.filled .cup-fill { opacity: 1 !important; }
.cup.filled .cup-check { opacity: 1 !important; }

.cup-counter-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}
#cup-counter { font-weight: 700; font-size: 1.05rem; color: var(--text-primary); }
.btn-reset {
  padding: 0.45rem 1rem;
  background: #fed7d7;
  color: #c53030;
  border: none;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition);
}
.btn-reset:hover { background: #feb2b2; }

/* ---- Progress Bar ---- */
.progress-wrap {
  background: #e2e8f0;
  border-radius: 100px;
  height: 18px;
  overflow: hidden;
  margin: 1rem 0 0.5rem;
}
#progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #93c5fd 0%, #4A90D9 50%, #1e40af 100%);
  border-radius: 100px;
  transition: width 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
.progress-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-secondary);
}
#motivation-msg {
  margin-top: 0.75rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--accent);
  text-align: center;
  min-height: 1.5em;
}

/* ---- Streak ---- */
#streak-days {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
  margin: 1rem 0 0.5rem;
}
.streak-day {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  flex: 1;
  min-width: 36px;
}
.streak-icon { font-size: 1.2rem; }
.streak-label { font-size: 0.7rem; color: var(--text-secondary); font-weight: 500; }
.streak-day.met .streak-label { color: #38a169; }
#streak-count { font-weight: 700; color: var(--accent); font-size: 1rem; margin-top: 0.25rem; }

/* ---- FAQ ---- */
.faq-item { margin-bottom: 1.25rem; }
.faq-item h3 { color: var(--accent); margin-bottom: 0.4rem; }
.faq-item p { color: var(--text-secondary); font-size: 0.95rem; }

/* ---- Footer ---- */
footer {
  background: #2d3748;
  color: #a0aec0;
  text-align: center;
  padding: 2rem 1rem;
  margin-top: 3rem;
  font-size: 0.875rem;
}
footer a { color: #90cdf4; text-decoration: none; transition: color var(--transition); }
footer a:hover { color: white; }
.footer-links { display: flex; gap: 1.5rem; justify-content: center; flex-wrap: wrap; margin-bottom: 0.75rem; }
#visitor-counter { font-size: 0.8rem; margin-top: 0.5rem; opacity: 0.8; }
.spinai-brand { font-weight: 700; color: #90cdf4; }

/* ---- Native Ad (between result and cup dashboard) ---- */
.ad-native {
  padding: 0.75rem;
  text-align: center;
  min-height: 60px;
}

/* ---- Sticky Mobile Bottom Banner ---- */
.ad-sticky-mobile {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  text-align: center;
  z-index: 100;
  background: rgba(255,255,255,0.96);
  box-shadow: 0 -2px 12px rgba(0,0,0,0.08);
  padding: 4px 0;
}

/* ---- Feedback Widget ---- */
.feedback-widget {
  position: fixed;
  bottom: 80px;
  right: 20px;
  z-index: 90;
}
.feedback-toggle {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: none;
  background: var(--accent);
  color: white;
  font-size: 1.3rem;
  cursor: pointer;
  box-shadow: 0 4px 16px rgba(74, 144, 217, 0.35);
  transition: transform var(--transition), box-shadow var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}
.feedback-toggle:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 24px rgba(74, 144, 217, 0.45);
}
.feedback-panel {
  position: absolute;
  bottom: 60px;
  right: 0;
  width: 260px;
  background: white;
  border-radius: var(--radius);
  box-shadow: 0 8px 32px rgba(0,0,0,0.15);
  padding: 1.25rem;
  animation: feedbackSlide 0.25s ease;
}
@keyframes feedbackSlide {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.feedback-title { font-weight: 700; font-size: 0.95rem; color: var(--text-primary); }
.feedback-desc { font-size: 0.8rem; color: var(--text-secondary); margin: 0.35rem 0 0.75rem; }
.btn-feedback-send {
  display: block;
  text-align: center;
  padding: 0.6rem;
  background: var(--accent);
  color: white;
  font-weight: 600;
  font-size: 0.85rem;
  border-radius: 8px;
  text-decoration: none;
  transition: background var(--transition);
}
.btn-feedback-send:hover { background: var(--accent-dark); }

/* ---- Content Pages ---- */
.content-text {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.8;
}
.content-list {
  list-style: none;
  padding: 0;
}
.content-list li {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.8;
  padding-left: 1.5rem;
  position: relative;
  margin-bottom: 0.5rem;
}
.content-list li::before {
  content: '•';
  color: var(--accent);
  font-weight: 700;
  position: absolute;
  left: 0;
}
ol.content-list { counter-reset: step; }
ol.content-list li { padding-left: 2rem; }
ol.content-list li::before {
  counter-increment: step;
  content: counter(step) ".";
  font-weight: 700;
}

/* ---- Step Blocks ---- */
.step-block {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}
.step-number {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent);
  color: white;
  font-weight: 800;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}
.step-content h3 { color: var(--text-primary); margin-bottom: 0.35rem; }

/* ---- Utility ---- */
.hidden { display: none !important; }
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }

/* ---- Responsive ---- */
@media (max-width: 768px) {
  .card { padding: 1.25rem; }
  h1 { font-size: 1.5rem; }
  .result-big .num { font-size: 1.8rem; }
  .ad-sticky-mobile { display: block; }
  body { padding-bottom: 60px; }
}

@media (min-width: 1024px) {
  .container { padding: 0 2rem; }
  .card { padding: 2rem; }
}