diff --git a/public/css/style.css b/public/css/style.css
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+/* ===== Reset & Base ===== */
+*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
+:root {
+  --bg-primary: #14141c;
+  --bg-secondary: #1b1b2f;
+  --bg-tertiary: #252540;
+  --accent-green: #1bb76e;
+  --accent-green-hover: #15995d;
+  --accent-red: #e74c3c;
+  --accent-red-hover: #c0392b;
+  --text-primary: #ffffff;
+  --text-secondary: #a0a0b8;
+  --text-muted: #6c6c85;
+  --border-color: #2a2a45;
+  --shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
+  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
+  --radius: 8px;
+  --radius-lg: 12px;
+  --transition: 0.2s ease;
+}
+body {
+  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+  background: var(--bg-primary);
+  color: var(--text-primary);
+  min-height: 100vh;
+  line-height: 1.6;
+}
+.header {
+  background: var(--bg-secondary);
+  border-bottom: 1px solid var(--border-color);
+  position: sticky;
+  top: 0;
+  z-index: 100;
+  box-shadow: var(--shadow);
+}
+.header-inner {
+  max-width: 1400px;
+  margin: 0 auto;
+  padding: 12px 24px;
+  display: flex;
+  align-items: center;
+  gap: 24px;
+}
+.logo {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  cursor: pointer;
+  flex-shrink: 0;
+}
+.logo-icon { font-size: 28px; }
+.logo-text {
+  font-size: 20px;
+  font-weight: 700;
+  color: var(--accent-green);
+}
+.search-bar {
+  flex: 1;
+  display: flex;
+  max-width: 500px;
+}
+.search-bar input {
+  flex: 1;
+  padding: 10px 16px;
+  background: var(--bg-tertiary);
+  border: 1px solid var(--border-color);
+  border-right: none;
+  border-radius: var(--radius) 0 0 var(--radius);
+  color: var(--text-primary);
+  font-size: 14px;
+  outline: none;
+  transition: border-color var(--transition);
+}
+.search-bar input:focus { border-color: var(--accent-green); }
+.search-bar input::placeholder { color: var(--text-muted); }
+.search-bar button {
+  padding: 10px 16px;
+  background: var(--bg-tertiary);
+  border: 1px solid var(--border-color);
+  border-radius: 0 var(--radius) var(--radius) 0;
+  cursor: pointer;
+  font-size: 14px;
+}
+.btn-new-post {
+  padding: 10px 20px;
+  background: var(--accent-green);
+  color: white;
+  border: none;
+  border-radius: var(--radius);
+  font-weight: 600;
+  font-size: 14px;
+  cursor: pointer;
+  transition: background var(--transition);
+  flex-shrink: 0;
+}
+.btn-new-post:hover { background: var(--accent-green-hover); }
+.filter-bar {
+  max-width: 1400px;
+  margin: 0 auto;
+  padding: 16px 24px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+}
+.filter-tabs { display: flex; gap: 8px; }
+.filter-tab {
+  padding: 8px 16px;
+  background: var(--bg-secondary);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius);
+  color: var(--text-secondary);
+  cursor: pointer;
+  font-size: 13px;
+  font-weight: 500;
+  transition: all var(--transition);
+}
+.filter-tab:hover {
+  border-color: var(--accent-green);
+  color: var(--text-primary);
+}
+.filter-tab.active {
+  background: var(--accent-green);
+  border-color: var(--accent-green);
+  color: white;
+}
+.post-count {
+  color: var(--text-muted);
+  font-size: 13px;
+}
+.gallery-container {
+  max-width: 1400px;
+  margin: 0 auto;
+  padding: 0 24px 48px;
+}
+.gallery-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
+  gap: 16px;
+}
+.post-card {
+  background: var(--bg-secondary);
+  border-radius: var(--radius-lg);
+  overflow: hidden;
+  cursor: pointer;
+  transition: transform var(--transition), box-shadow var(--transition);
+  border: 1px solid var(--border-color);
+}
+.post-card:hover {
+  transform: translateY(-2px);
+  box-shadow: var(--shadow-lg);
+}
+.post-card-image {
+  width: 100%;
+  aspect-ratio: 4/3;
+  object-fit: cover;
+  display: block;
+  background: var(--bg-tertiary);
+}
+.post-card-body { padding: 12px 16px; }
+.post-card-title {
+  font-size: 14px;
+  font-weight: 600;
+  margin-bottom: 8px;
+  display: -webkit-box;
+  -webkit-line-clamp: 2;
+  -webkit-box-orient: vertical;
+  overflow: hidden;
+}
+.post-card-stats {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  font-size: 12px;
+  color: var(--text-secondary);
+}
+.post-card-stats .upvotes {
+  color: var(--accent-green);
+  font-weight: 600;
+}
+.post-card-tags {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 4px;
+  margin-top: 8px;
+}
+.tag-pill {
+  padding: 2px 8px;
+  background: var(--bg-tertiary);
+  border-radius: 12px;
+  font-size: 11px;
+  color: var(--text-muted);
+}
+.loading {
+  text-align: center;
+  padding: 48px;
+  color: var(--text-muted);
+}
+.spinner {
+  width: 40px;
+  height: 40px;
+  border: 3px solid var(--border-color);
+  border-top-color: var(--accent-green);
+  border-radius: 50%;
+  animation: spin 0.8s linear infinite;
+  margin: 0 auto 16px;
+}
+@keyframes spin { to { transform: rotate(360deg); } }
+.modal-overlay {
+  display: none;
+  position: fixed;
+  top: 0; left: 0; right: 0; bottom: 0;
+  background: rgba(0, 0, 0, 0.8);
+  z-index: 1000;
+  align-items: center;
+  justify-content: center;
+  padding: 24px;
+}
+.modal-overlay.active { display: flex; }
+.modal {
+  background: var(--bg-secondary);
+  border-radius: var(--radius-lg);
+  width: 100%;
+  max-width: 560px;
+  max-height: 90vh;
+  overflow-y: auto;
+  border: 1px solid var(--border-color);
+  box-shadow: var(--shadow-lg);
+}
+.modal-large { max-width: 960px; }
+.modal-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 16px 24px;
+  border-bottom: 1px solid var(--border-color);
+}
+.modal-header h2 {
+  font-size: 18px;
+  font-weight: 600;
+}
+.modal-close {
+  background: none;
+  border: none;
+  color: var(--text-secondary);
+  font-size: 18px;
+  cursor: pointer;
+  padding: 4px 8px;
+  border-radius: 4px;
+  transition: all var(--transition);
+}
+.modal-close:hover {
+  background: var(--bg-tertiary);
+  color: var(--text-primary);
+}
+.modal-body { padding: 24px; }
+.upload-zone {
+  border: 2px dashed var(--border-color);
+  border-radius: var(--radius-lg);
+  padding: 48px 24px;
+  text-align: center;
+  cursor: pointer;
+  transition: border-color var(--transition), background var(--transition);
+  margin-bottom: 24px;
+}
+.upload-zone:hover,
+.upload-zone.dragover {
+  border-color: var(--accent-green);
+  background: rgba(27, 183, 110, 0.05);
+}
+.upload-icon {
+  font-size: 48px;
+  margin-bottom: 16px;
+}
+.upload-prompt p {
+  color: var(--text-secondary);
+  margin-bottom: 4px;
+}
+.upload-hint {
+  font-size: 13px;
+  color: var(--text-muted);
+}
+.upload-formats {
+  font-size: 12px;
+  color: var(--text-muted);
+  margin-top: 8px;
+}
+.upload-preview {
+  position: relative;
+  display: inline-block;
+}
+.upload-preview img {
+  max-width: 100%;
+  max-height: 300px;
+  border-radius: var(--radius);
+}
+.btn-remove {
+  position: absolute;
+  top: 8px;
+  right: 8px;
+  background: rgba(0, 0, 0, 0.7);
+  color: white;
+  border: none;
+  border-radius: 50%;
+  width: 32px;
+  height: 32px;
+  cursor: pointer;
+  font-size: 14px;
+}
+.form-group { margin-bottom: 20px; }
+.form-group label {
+  display: block;
+  margin-bottom: 6px;
+  font-size: 13px;
+  font-weight: 500;
+  color: var(--text-secondary);
+}
+.form-group input {
+  width: 100%;
+  padding: 10px 14px;
+  background: var(--bg-tertiary);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius);
+  color: var(--text-primary);
+  font-size: 14px;
+  outline: none;
+  transition: border-color var(--transition);
+}
+.form-group input:focus { border-color: var(--accent-green); }
+.form-group input::placeholder { color: var(--text-muted); }
+.btn-submit {
+  width: 100%;
+  padding: 12px;
+  background: var(--accent-green);
+  color: white;
+  border: none;
+  border-radius: var(--radius);
+  font-size: 15px;
+  font-weight: 600;
+  cursor: pointer;
+  transition: background var(--transition);
+}
+.btn-submit:hover { background: var(--accent-green-hover); }
+.btn-submit:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+}
+.error-message {
+  background: rgba(231, 76, 60, 0.1);
+  border: 1px solid var(--accent-red);
+  color: var(--accent-red);
+  padding: 10px 14px;
+  border-radius: var(--radius);
+  margin-bottom: 16px;
+  font-size: 13px;
+}
+.post-detail-grid {
+  display: grid;
+  grid-template-columns: 1fr 280px;
+  gap: 24px;
+  margin-bottom: 24px;
+}
+.post-image-container img {
+  width: 100%;
+  border-radius: var(--radius);
+  cursor: zoom-in;
+}
+.vote-box {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  margin-bottom: 16px;
+}
+.vote-btn {
+  padding: 8px 16px;
+  background: var(--bg-tertiary);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius);
+  color: var(--text-secondary);
+  cursor: pointer;
+  font-size: 16px;
+  font-weight: 700;
+  transition: all var(--transition);
+}
+.vote-btn:hover {
+  border-color: var(--accent-green);
+  color: var(--accent-green);
+}
+.vote-btn.active-up {
+  background: var(--accent-green);
+  border-color: var(--accent-green);
+  color: white;
+}
+.vote-btn.active-down {
+  background: var(--accent-red);
+  border-color: var(--accent-red);
+  color: white;
+}
+.vote-count {
+  font-size: 20px;
+  font-weight: 700;
+  color: var(--accent-green);
+}
+.post-meta {
+  display: flex;
+  gap: 16px;
+  margin-bottom: 16px;
+  font-size: 13px;
+  color: var(--text-secondary);
+}
+.post-tags {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 6px;
+  margin-bottom: 16px;
+}
+.post-tags .tag-pill {
+  padding: 4px 10px;
+  font-size: 12px;
+}
+.post-author {
+  font-size: 13px;
+  color: var(--text-secondary);
+  margin-bottom: 4px;
+}
+.post-author strong { color: var(--accent-green); }
+.post-date {
+  font-size: 12px;
+  color: var(--text-muted);
+}
+.comments-section {
+  border-top: 1px solid var(--border-color);
+  padding-top: 24px;
+}
+.comments-section h3 {
+  font-size: 16px;
+  margin-bottom: 16px;
+}
+.comment-form {
+  display: flex;
+  gap: 12px;
+  margin-bottom: 24px;
+}
+.comment-form input {
+  flex: 1;
+  padding: 10px 14px;
+  background: var(--bg-tertiary);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius);
+  color: var(--text-primary);
+  font-size: 14px;
+  outline: none;
+}
+.comment-form input:focus { border-color: var(--accent-green); }
+.btn-comment {
+  padding: 10px 20px;
+  background: var(--accent-green);
+  color: white;
+  border: none;
+  border-radius: var(--radius);
+  font-weight: 600;
+  cursor: pointer;
+  transition: background var(--transition);
+}
+.btn-comment:hover { background: var(--accent-green-hover); }
+.comment-item {
+  padding: 12px 0;
+  border-bottom: 1px solid var(--border-color);
+}
+.comment-item:last-child { border-bottom: none; }
+.comment-item.reply {
+  margin-left: 32px;
+  border-left: 2px solid var(--border-color);
+  padding-left: 16px;
+}
+.comment-author {
+  font-size: 13px;
+  font-weight: 600;
+  color: var(--accent-green);
+  margin-bottom: 4px;
+}
+.comment-text {
+  font-size: 14px;
+  color: var(--text-secondary);
+}
+.comment-time {
+  font-size: 11px;
+  color: var(--text-muted);
+  margin-top: 4px;
+}
+.fullscreen-overlay {
+  display: none;
+  position: fixed;
+  top: 0; left: 0; right: 0; bottom: 0;
+  background: rgba(0, 0, 0, 0.95);
+  z-index: 2000;
+  align-items: center;
+  justify-content: center;
+  cursor: zoom-out;
+}
+.fullscreen-overlay.active { display: flex; }
+.fullscreen-overlay img {
+  max-width: 90%;
+  max-height: 90%;
+  object-fit: contain;
+}
+.toast-container {
+  position: fixed;
+  bottom: 24px;
+  right: 24px;
+  z-index: 3000;
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
+}
+.toast {
+  padding: 12px 20px;
+  background: var(--bg-secondary);
+  border: 1px solid var(--border-color);
+  border-radius: var(--radius);
+  color: var(--text-primary);
+  font-size: 14px;
+  box-shadow: var(--shadow-lg);
+  animation: slideIn 0.3s ease;
+}
+.toast.success {
+  border-color: var(--accent-green);
+  color: var(--accent-green);
+}
+.toast.error {
+  border-color: var(--accent-red);
+  color: var(--accent-red);
+}
+@keyframes slideIn {
+  from { transform: translateX(100%); opacity: 0; }
+  to { transform: translateX(0); opacity: 1; }
+}
+@media (max-width: 1024px) {
+  .post-detail-grid { grid-template-columns: 1fr; }
+  .post-sidebar { order: -1; }
+}
+@media (max-width: 768px) {
+  .header-inner {
+    flex-wrap: wrap;
+    gap: 12px;
+    padding: 12px 16px;
+  }
+  .search-bar {
+    order: 3;
+    max-width: 100%;
+    width: 100%;
+  }
+  .filter-bar { padding: 12px 16px; }
+  .filter-tabs {
+    overflow-x: auto;
+    gap: 6px;
+  }
+  .filter-tab {
+    padding: 6px 12px;
+    font-size: 12px;
+    white-space: nowrap;
+  }
+  .gallery-container { padding: 0 16px 32px; }
+  .gallery-grid {
+    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
+    gap: 12px;
+  }
+  .modal { max-width: 100%; margin: 16px; }
+  .modal-large { max-width: 100%; }
+}
+@media (max-width: 375px) {
+  .gallery-grid { grid-template-columns: 1fr; }
+  .logo-text { display: none; }
+  .btn-new-post {
+    padding: 8px 14px;
+    font-size: 13px;
+  }
+}
\ No newline at end of file