/* =========================================================
   CTO Bird Study - main stylesheet (AC2.2 - format)
   Author: Sinan Sarikaya
   ========================================================= */

:root {
  --navy: #0B2545;
  --blue: #1B4F9C;
  --sky: #EAF1FB;
  --red: #B3261E;
  --ink: #1A1A1A;
  --muted: #5B6B79;
  --line: #DDDDDD;
  --radius: 8px;
  --shadow: 0 2px 10px rgba(11, 37, 69, 0.08);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: #F7F9FC;
  line-height: 1.55;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

a { color: var(--blue); }

img { max-width: 100%; height: auto; }

/* ---------- Header and navigation bar ---------- */
.site-header { background: var(--navy); color: #FFFFFF; }

.nav {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0.8rem 1.2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.brand {
  color: #FFFFFF;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.15rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand img { width: 34px; height: 34px; }

.nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.3rem;
}

.nav-link {
  color: #DCE6F5;
  text-decoration: none;
  padding: 0.45rem 0.8rem;
  border-radius: var(--radius);
  display: block;
}

.nav-link:hover,
.nav-link:focus,
.nav-link.active {
  background: var(--blue);
  color: #FFFFFF;
}

.nav-user { color: #FFFFFF; font-size: 0.9rem; padding: 0.45rem 0.4rem; }

.nav-user[hidden], .nav-item[hidden] { display: none; }

/* ---------- Layout ---------- */
main {
  flex: 1;
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 1.5rem 1.2rem 2.5rem;
}

h1, h2, h3 { color: var(--navy); line-height: 1.25; }

.lead { color: var(--muted); font-size: 1.05rem; }

/* ---------- Landing page ---------- */
.hero {
  border-radius: 12px;
  padding: 4rem 2rem;
  color: #FFFFFF;
  background-color: var(--navy);
  background-image:
    linear-gradient(90deg, rgba(11, 37, 69, 0.88), rgba(11, 37, 69, 0.2)),
    url("../images/hero.jpg"),
    url("../images/hero.svg");
  background-size: cover;
  background-position: center;
  box-shadow: var(--shadow);
}

.hero h1 { color: #FFFFFF; font-size: 2.3rem; margin: 0 0 0.6rem; max-width: 20ch; }

.hero p { max-width: 55ch; font-size: 1.1rem; }

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.2rem;
  margin: 2rem 0;
}

.card {
  background: #FFFFFF;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  box-shadow: var(--shadow);
}

.card h2, .card h3 { font-size: 1.2rem; margin-top: 0; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  border: 0;
  border-radius: var(--radius);
  padding: 0.6rem 1.2rem;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  background: var(--blue);
  color: #FFFFFF;
}

.btn:hover, .btn:focus { background: var(--navy); }

.btn-light { background: #FFFFFF; color: var(--navy); }

.btn-light:hover, .btn-light:focus { background: var(--sky); }

.btn-small { padding: 0.35rem 0.8rem; font-size: 0.9rem; }

.btn-danger { background: var(--red); }

.btn-danger:hover, .btn-danger:focus { background: #7F1B15; }

.btn-secondary { background: #6B7785; }

/* ---------- Forms ---------- */
.form-card {
  background: #FFFFFF;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem;
  box-shadow: var(--shadow);
  max-width: 680px;
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem 1.2rem;
}

.form-grid .full { grid-column: 1 / -1; }

label, legend { display: block; font-weight: 600; margin-bottom: 0.3rem; color: var(--navy); }

fieldset { border: 0; margin: 0; padding: 0; }

.radio-row { display: flex; flex-wrap: wrap; gap: 0.4rem 1.2rem; }

.radio-row label { font-weight: 400; color: var(--ink); display: inline-flex; gap: 0.35rem; align-items: center; }

input[type="text"],
input[type="email"],
input[type="password"],
input[type="date"],
input[type="time"],
input[type="number"],
input[type="search"],
input[type="file"],
select,
textarea {
  width: 100%;
  padding: 0.55rem 0.7rem;
  border: 1px solid #B8C4D2;
  border-radius: 6px;
  font: inherit;
  background: #FFFFFF;
}

input:focus, select:focus, textarea:focus { outline: 2px solid var(--blue); outline-offset: 1px; }

textarea { min-height: 110px; resize: vertical; }

.hint { color: var(--muted); font-size: 0.85rem; margin: 0.25rem 0 0; }

#postingAs { margin: 0 0 1rem; }

.field-error { display: block; color: var(--red); font-size: 0.88rem; margin-top: 0.25rem; }

.field-error[hidden] { display: none; }

.form-actions { margin-top: 1.2rem; display: flex; gap: 0.6rem; flex-wrap: wrap; align-items: center; }

/* ---------- Status banners ---------- */
.banner {
  border-radius: var(--radius);
  padding: 0.8rem 1rem;
  margin-bottom: 1.2rem;
  background: #E7F4EC;
  border: 1px solid #9FD1B2;
  color: #1D5433;
}

.banner.error { background: #FBEAEA; border-color: #E4A9A5; color: #7F1B15; }

.banner[hidden] { display: none; }

/* ---------- Message board ---------- */
.search-bar { display: flex; gap: 0.6rem; margin: 1rem 0 1.5rem; max-width: 680px; }

.post-list { display: grid; gap: 1rem; }

.post-card{
  border:1px solid #ddd; border-radius:8px; padding:1rem 1.2rem;
  display:grid; grid-template-columns:110px 1fr auto; gap:1rem;
  background: #FFFFFF;
  box-shadow: var(--shadow);
  align-items: start;
}

.post-thumb {
  width: 110px;
  height: 110px;
  object-fit: cover;
  border-radius: 6px;
  background: var(--sky);
}

.post-card h3 { margin: 0 0 0.3rem; font-size: 1.15rem; }

.post-meta { color: var(--muted); font-size: 0.9rem; margin: 0 0 0.5rem; }

.post-comments { margin: 0 0 0.5rem; white-space: pre-wrap; }

.post-author { font-size: 0.85rem; color: var(--muted); margin: 0; }

.post-actions { display: flex; flex-direction: column; gap: 0.4rem; }

.tag {
  display: inline-block;
  background: var(--sky);
  color: var(--blue);
  border-radius: 999px;
  padding: 0.05rem 0.6rem;
  font-size: 0.8rem;
  font-weight: 600;
}

.edit-form { grid-column: 1 / -1; border-top: 1px dashed var(--line); padding-top: 1rem; }

.edit-form label select,
.edit-form label input,
.edit-form label textarea { font-weight: 400; margin-top: 0.3rem; }

.empty { color: var(--muted); font-style: italic; }

/* ---------- Footer ---------- */
.site-footer { background: var(--navy); color: #C9D6E8; font-size: 0.88rem; }

.site-footer .inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1rem 1.2rem;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.site-footer a { color: #FFFFFF; }

.site-footer p { margin: 0.2rem 0; }

.student-id { font-weight: 600; color: #FFFFFF; }

/* ---------- Responsive breakpoint ---------- */
@media (max-width:640px){
  .post-card{ grid-template-columns:1fr; }
  .form-grid { grid-template-columns: 1fr; }
  .hero { padding: 2.5rem 1.2rem; }
  .hero h1 { font-size: 1.8rem; }
  .post-actions { flex-direction: row; }
}