:root { --main: #6e8efb; --bg: #f8f9fa; --red: #ff4757; --green: #4cd137; }
body { font-family: -apple-system, sans-serif; margin: 0; background: var(--bg); overflow-x: hidden; -webkit-tap-highlight-color: transparent; }
.hidden { display: none !important; }

/* Header & Online Status Stack */
.app-header { height: 75px; background: white; display: flex; justify-content: space-between; align-items: center; padding: 0 20px; position: fixed; top: 0; width: 100%; z-index: 1000; border-bottom: 1px solid #eee; box-sizing: border-box; }
.header-left { display: flex; flex-direction: column; }
.logo { font-size: 20px; font-weight: 800; color: var(--main); }
.live-status { display: flex; align-items: center; gap: 5px; color: var(--green); font-size: 10px; font-weight: bold; margin-top: 2px; }
.pulse-dot { width: 6px; height: 6px; background: var(--green); border-radius: 50%; animation: pulse 1.5s infinite; }
@keyframes pulse { 0% { opacity: 1; } 50% { opacity: 0.3; } 100% { opacity: 1; } }

#user-info { display: flex; align-items: center; gap: 15px; }
.circle-pfp { width: 38px; height: 38px; border-radius: 50% !important; object-fit: cover; border: 1.5px solid #eee; }
.large-pfp { width: 90px; height: 90px; border: 3px solid var(--main); margin: 0 auto 10px auto; display: block; }

.screen { padding: 95px 15px 100px 15px; max-width: 480px; margin: 0 auto; box-sizing: border-box; }

/* Filters */
.filter-bar { display: flex; gap: 8px; overflow-x: auto; padding: 10px 0; scrollbar-width: none; }
.filter-bar::-webkit-scrollbar { display: none; }
.chip { padding: 7px 18px; background: white; border-radius: 20px; font-size: 12px; border: 1px solid #eee; cursor: pointer; white-space: nowrap; font-weight: 600; color: #555; }
.chip.active { background: var(--main); color: white; border: none; }

/* Cards & Organization */
.post-card { background: white; padding: 18px; border-radius: 20px; margin-bottom: 15px; border: 1px solid #eee; position: relative; }
.priority-card { border: 2px solid var(--red) !important; background: #fffafa !important; }
.tutor-badge { background: var(--red); color: white; font-size: 9px; padding: 4px 8px; border-radius: 6px; font-weight: 900; margin-bottom: 10px; display: inline-flex; align-items: center; gap: 4px; }
.post-actions { display: flex; gap: 15px; margin-top: 15px; padding-top: 15px; border-top: 1px solid #f9f9f9; }
.action-item { display: flex; align-items: center; gap: 5px; font-size: 13px; font-weight: 600; cursor: pointer; color: #666; }
.bookmark-btn { margin-left: auto; font-size: 22px; color: #ccc; cursor: pointer; }
.bookmark-btn.saved { color: #fbc531; }

/* Modal Organization */
.modal-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; margin-bottom: 20px; }
.input-group { display: flex; flex-direction: column; gap: 5px; }
.input-group label { font-size: 10px; font-weight: bold; color: #aaa; text-transform: uppercase; }
.input-group select { padding: 12px; border-radius: 12px; border: 1px solid #eee; background: #f9f9f9; font-size: 14px; outline: none; }

/* Profile Tabs */
.profile-tabs { display: flex; background: #f0f2f5; border-radius: 12px; padding: 5px; margin: 20px 0; }
.p-tab { flex: 1; padding: 10px; border-radius: 8px; font-size: 13px; cursor: pointer; text-align: center; color: #777; font-weight: 600; }
.p-tab.active { background: white; color: var(--main); box-shadow: 0 2px 5px rgba(0,0,0,0.05); }

/* Nav */
.bottom-nav { position: fixed; bottom: 0; width: 100%; height: 70px; background: white; display: flex; justify-content: space-around; align-items: center; border-top: 1px solid #eee; padding-bottom: env(safe-area-inset-bottom); }
.add-btn { background: var(--main); color: white; width: 55px; height: 55px; border-radius: 50%; display: flex; align-items: center; justify-content: center; margin-top: -35px; border: 5px solid var(--bg); font-size: 30px; box-shadow: 0 4px 10px rgba(110, 142, 251, 0.3); }
.primary-btn { width: 100%; background: var(--main); color: white; border: none; padding: 16px; border-radius: 16px; font-weight: bold; cursor: pointer; font-size: 16px; }
.login-btn { padding: 15px 40px; background: var(--main); color: white; border: none; border-radius: 30px; font-weight: bold; font-size: 16px; cursor: pointer; box-shadow: 0 4px 15px rgba(110, 142, 251, 0.2); }
.logout-link { margin-top: 30px; background: none; border: none; color: var(--red); cursor: pointer; font-weight: bold; display: block; width: 100%; }